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Deep-Seated Gravitational Slope Deformations (DSGSDs) are common in many geological environments, and due to their common limited displacement rate, they can remain unrecognized for a long time. Among the most significant events in Sicily is the Mt. San Calogero DSGSD. To contribute to a better understanding of its characteristics, including the geologic setting promoting its development, ongoing kinematics, and mechanism, a specific analysis was completed. In this paper, the results of this analysis, based on a three-folded strategy, are provided and interpreted in the context of DSGSD predisposing conditions and controlling factors. Especially, field observations associated to visual interpretation of aerial imagery were used for the identification and mapping of main geological features and landforms, high-resolution X-Band DInSAR data enabled researchers to fully characterize the deformational behavior of the slope, while a reduced complexity slope stability analysis allowed them to reconstruct the deep geometry of the DSGSD. Results from the analysis indicate that the DSGSD of Mt. San Calogero is composed of three blocks corresponding to fault-bounded tectonic elements and characterized by a specific kinematics and sensitivity to external forcing (i.e., rainfall), multiple landslides are associated to the DSGSD in the area and the deep geometry of the DSGSD is concave upward and resemble the characteristics of a rotational slide. The interpretation of the results suggests that the formation and the deformation of the Mt. San Calogero DSGSD are linked with the local and regional fault systems related to the Sicilian orogen, while shallow landslides are triggered, in clayey terrains, mostly by rainfalls. In addition, the integrated approach reveals that active tectonics and rainfalls in the San Calogero massive relief are the main driving forces of its different deformation behavior. [ABSTRACT FROM AUTHOR]

Since the 1970s, it has been widely accepted that the Nördlinger Ries and the Steinheim impact structures represent a crater doublet formed by the simultaneous impact of a binary asteroid in the Middle Miocene. From a biostratigraphic point of view, however, the lowermost crater-lake sediments deposited in the drainless morphological depressions differ in age by ~ 0.5 to 1 Myr. Recent work additionally questioned the double-impact theory due to the occurrence of two vertically separated seismite horizons in North Alpine Foreland Basin deposits, interpreted to result from two different impact-induced seismic events. A continuous double-layer ejecta blanket originally surrounded the Ries crater within a minimum distance of 45 km from its center. Distal Ries ejecta consist of sedimentary and shocked basement rock fragments of the Ries area. The Steinheim crater is located 41 km WSW of the Ries crater and filled by a 'basin breccia' that consist of Middle and Upper Jurassic rock fragments. Most parts of the breccia and overlying crater-lake deposits are preserved. If both craters formed simultaneously, Ries ejecta would have reached the Steinheim area and should be incorporated in the Steinheim breccia or intercalated between the basin breccia and crater-lake deposits. However, no sedimentary or basement rock fragments derived from the Ries crater have ever been found in outcrops or drillings into the Steinheim crater. We conclude the Steinheim impact crater did not exist at the time of the Ries impact and the Steinheim asteroid rather impacted into the outer continuous distal Ries ejecta blanket some 0.5 to 1 Myr after the Ries impact. Geological map of the Ries crater with the present distribution of its ejecta blanket and the geographical position of the Steinheim crater ~41 km WSW of the Ries crater. The Ries ejecta blanket consists of the more proximal type of impact breccia (Bunte Breccia) and the more distal type of impact breccia (Bunte Trümmermassen) [ABSTRACT FROM AUTHOR]

The 2D geological map serves as a synthesis of geological investigations and expert knowledge, making it a crucial data source for bedrock 3D modeling. Nevertheless, insufficient geological information mining has been a problem in previous research utilizing 2D geological maps for bedrock modeling. To address this issue, this paper proposes a 3D bedrock modeling method that incorporates multiple information mining based on 2D geological maps. The method involves extracting surface undulation, occurrence, stratigraphic age, and other information from the 2D geological map multiple times using map-cut cross sections and virtual drills. This information is then stored using the generalized trigonal prismatic (GTP) element. Additionally, the paper introduces connection rules to handle different geological phenomena, such as stratigraphic pinch-out, stratigraphic inversion, stratigraphic duplication, and unconformity contact, and their corresponding GTP types. Finally, the GTPs are connected according to these rules, resulting in the construction of a 3D bedrock model. To validate the method's consistency with expert speculation regarding the expression of geological body structures and occurrence, the paper compares a slice section of the example modeling results with expert hand-drawn section from the same location. The results demonstrate that the proposed modeling method effectively explores the geological information present in the planar geological map and clearly expresses a variety of complex geological formations, enabling the construction of a high-quality 3D bedrock model. [ABSTRACT FROM AUTHOR]

The Basin and Range Province of the western United States has inspired or augmented many important geological ideas but is most famous for the concept of crustal extension. Acceptance of the concept was a slow process. Prior to the recognition of plate tectonics, extension was unexpected and hard to understand; when mapping of the region began in the 1860s, mountain ranges were assumed to be the products of crustal compression due to contraction of the Earth. The first mapping suggested that ranges are anticlinal folds, but the idea of uplift along vertical range-bounding faults arose shortly thereafter. There was recognition starting in the 1880s that at least some faults were normal-sense rather than vertical, which implied extension, but there were decades of dissent by geologists who still promoted the anticlinal-folding idea, thought that inclined faults were reverse faults, or believed that the basins and ranges were created by water or wind or glacial erosion rather than tectonics. Normal faulting gradually became widely accepted, but comprehension of its meaning was hindered by apparent thrust faults in parts of the province that suggested contractional deformation. These faults would later be interpreted as low-angle normal faults, and crustal extension became widely, though not universally, accepted in the 1960s as magnetic anomalies confirmed seafloor spreading. Roughly a century elapsed between the first geologic mapping and general acceptance of crustal extension. A parallel evolution of thought occurred in Africa as a consensus arose that rift valleys were products of extension [ABSTRACT FROM AUTHOR]

Uncertainty of a geoscientific map derived from data sampled by sensory engagement of human experts cannot be quantified from within the processing chain followed to produce the map due to subjective components in the underlying data. Nevertheless, quantified uncertainty associated with such maps would be essentially required for correct information retrieval from such maps. An approach mimicking an expert elicitation through digital agents in an information fusion procedure is suggested to quantify the trustworthiness of a partially subjective map (such as a soil map or any other geoscientific map inherently linked to partial subjectivity, e.g., a geological map). This procedure links a partially subjective map with collocated maps resulting from technical measurements provided with quantified uncertainty. Variation of methodology in this approach results in an ensemble of maps with variable degree of matching with the partially subjective map which allows for probabilistic statements about the trustworthiness of the partially subjective map. This enables including partially subjective maps in further data integration relying on numerical analysis, e.g., in the context of computational modeling or machine learning. By being able to assign a quantitative trustworthiness to a partially subjective map the risk of over-utilization of this map is reduced. [ABSTRACT FROM AUTHOR]

Venus preserves ∼1,000 impact craters, yet to date no impact basins larger than 300 km in diameter—common in the oldest terrains on Mercury, Mars and the Moon—are recognized on Venus. The tessera terrain is Venus' oldest recognized terrain. We describe a ∼1,500 km‐diameter concentric ring‐graben complex preserved on Haasttse‐baad Tessera, Venus that we identify as the Haasttse‐baad Tessera Ring Complex (HTRC). Based on geologic relations and numerical modeling, we propose that the HTRC may represent a Valhalla‐type multiring impact basin formed late during the evolution of its host ribbon‐tessera terrain (rtt). Formation of Valhalla‐type impact basins could involve a unique three‐layer target rheology with a thin elastic layer above a low viscosity layer above a deep strong layer. This multi‐layer rheological sandwich is consistent with crustal rheology previously proposed for the formation of Venus' rtt. If the HTRC is a Valhalla‐type impact basin, it would be Venus' oldest, and currently largest, impact structure, providing a rare window into Venus' ancient past and with implications for early crustal processes on Venus. Plain Language Summary: Venus preserves ∼1,000 impact craters, but no craters larger than 300 km—common on Mercury, Mars, and Moon—are recognized. We describe a large circular structure (∼1,500 km‐diameter) that formed on tessera terrain, Venus' oldest recognized surface type. The structure consists of concentric circular troughs that cut the tessera surface; geologic mapping shows that the structure formed late during tessera formation. We discuss the different mechanisms for forming large circular features marked by concentric rings of structures, and propose that it could be an example of a large impact basin named Valhalla‐type impact basin after a structure present in Jupiter's moon Callisto. Previous research suggests that the formation of these impact basins likely involves a distinctive layering in the impact site consisting of a sandwich of layers with different strengths (strong‐weak‐strong), a configuration previously proposed as necessary to form the host tessera terrain. Numerical models show that forming the circular structure as a Valhalla‐type impact basin is possible if a large meteorite crashes into this three‐layer crust. This unique structure, which might represent a very old and large impact structure, could provide a rare window into Venus' ancient past. Key Points: We describe a unique ∼1,500 km‐diameter concentric ring complex and present detailed geologic maps of the structure and its host tesseraWe propose that this structure may represent a Valhalla‐type impact structure, as supported by geologic mapping and numerical modelingIf the hypothesis is valid, the complex is the largest impact structure recognized on Venus, with implications for early planet processes [ABSTRACT FROM AUTHOR]

Planetary geologic maps are crucial tools for understanding the geological features and processes of solid bodies in the Solar System. Over the past six decades, best practices in planetary geologic mapping have emphasized clear and objective observation, geological interpretation, multi‐sensor fusion, and iterative revision of maps based on new data. We summarize here four ways in which maps serve as indispensable instruments for scientific investigation, from enhancing observations to interrogating surface processes. With respect to space exploration, we underscore the role of planetary geologic maps as tools to link testable, hypothesis‐driven science to exploration goals and provide actionable information for hazard identification, resource evaluation, sample collection, and potential infrastructure development. To further advance the field of planetary geologic mapping, international collaboration is essential. This includes sharing data and maps through FAIR (findable, accessible, interoperable, and reusable) platforms, establishing standardized mapping practices, promoting diverse nomenclature, and fostering continued cooperation in space exploration. Plain Language Summary: We summarize why planetary geologic maps are important for science and space exploration. We review the history of these maps and present four ways in which planetary geologic maps contribute to scientific understanding. We further outline six ways in which maps help humanity plan and execute space missions productively and safely. These endeavors require international participation; thus, we end with a call for collaboration to train the next generation of mappers, develop maps for future missions, and use maps to communicate the significance of space exploration to everyone. Key Points: Planetary geologic maps are critical products that link science goals and objectives to space explorationMaps are also used to support safe and productive surface navigation and are imperative for crewed and robotic surface missionsInternational cooperation is essential to produce maps needed in the coming decade [ABSTRACT FROM AUTHOR]

Large topographic rises on Venus are regions thought to be formed in response to the presence of a mantle plume or mantle upwelling, equivalent to hot spots on Earth. In this work, we study the geology and evolution of one of these large topographic rises, Imdr Regio, based on geologic mapping and analysis of geophysical data of the area. Imdr Regio presents a complex structure with two very different areas: (a) an elevated southeast area that is dominated by volcanism associated with Idunn Mons, a large volcano that has been proposed as a site of recent or even active volcanism; (b) another elevated area in the northwest area that also has a large volcano (Arasy Mons), but that is dominated by volcanism and tectonic activity associated with the formation of the Olapa Chasma rift system. These two very differentiated topographically elevated areas also exhibit differences in their geology, volcanic and tectonic style, and geophysical characteristics, which leads us to suggest that more than the classic volcano‐dominated rise classification attributed to Imdr Regio the area could rather be considered as an intermediate or hybrid volcano‐rift dominated large topographic rise. The evaluation of the different genetic scenarios and its correspondence with the observed geology in the area suggests that the complex geology of Imdr Regio could be better explained if we consider models of hot spot evolution that involve the presence of several mantle plumes or secondary upwellings derived from a mantle plume emplaced at a deeper rheological boundary. Plain Language Summary: Large topographic rises on Venus are the equivalent to hot spots like those responsible for the formation of Hawaii on the Earth. We have studied the geologic evolution of one of these large topographic rises, Imdr Regio, and this research shows that Imdr Regio is complex with two differentiated areas. The southeast is dominated by a large volcano, Idunn Mons, that has been proposed as a site of recent or even active volcanism. In the northwest there is also a large volcano Arasy Mons, but the activity is dominated by the Olapa Chasma rift system. The presence of these two areas with differences in their geology, volcanic and tectonic style, and geophysical characteristics, leads us to suggest that, although this large topographic rise was classified as dominated by the volcano, it could indeed be better classified as an intermediate or hybrid volcano‐rift dominated rise. We also evaluate the different scenarios to explain its formation and conclude that the complex geology of Imdr Regio could be better explained if we consider models of hot spot evolution that involve the presence of several mantle plumes or secondary smaller plumes derived from a mantle plume emplaced at a greater depth. Key Points: We have studied the geology of Imdr Regio, a possible active hotspot on Venus, based on geologic mapping and analysis of geophysical dataImdr Regio presents complex geology dominated by Idunn Mons and Olapa Chasma, classifying it as a hybrid volcano‐rift large topographic riseThe complex geology and the topography of Imdr Regio suggest that it could be the result of multiple or secondary plumes in the area [ABSTRACT FROM AUTHOR]

We use the crystallinity of hydrated silica, represented by the 1.4 μm absorption position in orbiter spectroscopic data, as a proxy for the longevity of water–rock interaction in the Syrtis Major region. Geological maps and crater size–frequency distribution analyses are employed to contextualize mineral detections and estimate surface ages. Hydrated silica is detected within two distinct geological units: a younger "volcanic terrain" (vt) unit (∼2.4 Ga) and an older "highland terrain" (ht) unit (3.5–3.7 Ga). Hydrated silica in the vt unit typically has a band position <1.41 μm, consistent with amorphous opal‐A, suggesting these younger terrains have experienced limited interaction with water. In contrast, hydrated silica in the older highlands typically has a band position >1.41 μm, indicating opal‐CT, suggesting that these deposits have had more time to interact with water, while also producing accessory minerals such as kaolinite and Fe/Mg phyllosilicates. Plain Language Summary: This study explores the interactions between water and rocks in a region on Mars known as Syrtis Major by investigating a mineral‐like substance called hydrated silica. The structure of hydrated silica helps us estimate the extent of water interaction and its effects on the rocks. We used satellite data to locate this mineral across Syrtis Major and infer its crystal structure. Furthermore, we developed detailed geological maps and estimated surface ages to understand the geological context. We found that hydrated silica is located in two different types of areas: (a) a younger volcanic region; and (b) an older highland region. In the younger volcanic areas, it appears that less crystalline hydrated silica formed by interaction with small amounts of water, possibly during later volcanic activity. In the older highlands, more crystalline hydrated silica likely interacted with water for a longer duration or in larger amounts. This information aligns with the idea that the older highlands experienced more extensive or long‐lasting interactions with water compared to the younger volcanic regions. It provides insights into different wet periods in Mars' past, aiding our understanding of the planet's geological history and the role water played in shaping its surface. Key Points: We analyzed the crystallinity of hydrated silica in Syrtis Major to infer the extent and longevity of water–rock interactionAmorphous silica is found in young volcanic terrains within Nili and Meroe Paterae and more crystalline silica in the older highlandsOlder highland regions likely underwent a longer interaction with water compared to younger volcanic terrains [ABSTRACT FROM AUTHOR]

The mechanism of surface subsidence induced by shallow buried excavation construction and the failure mode under ultimate state were not unclear. In view of this situation, a scaled model experiment based on particle image velocimetry(PIV)was conducted to simulate the construction process of shallow buried tunnels in sandy soil and Ⅴ-grade surrounding rock. PIV technology was used to analyze the deformation images of the surrounding rock during the construction process of the tunnel, and to obtain displacement cloud maps of geological deformation induced by construction disturbance. By analyzing the characteristics and gradual evolution of surface deformation induced by underground excavation construction disturbance, the shape and range of the failure surface and collapse induced by underground excavation tunnel construction in different strata under the limit state were summarized. The equation of the failure surface induced by the collapse of the arch top strata during underground excavation construction was derived by using the upper limit theorem of limit analysis and variational principle, and the collapse surface graph was drawn. The validity of the model test results was verified by comparing the range of collapse induced by underground excavation construction in the arch crown strata obtained from the model test with the theoretical calculation results. [ABSTRACT FROM AUTHOR]

There is a growing trend towards utilizing nickel as a raw material for non-steel products due to the increasing demand for nickel up to 2040. Data shows that global nickel production and reserves will increase until 2021. As one of the countries with the largest reserves in the world, this country contributes significantly to global nickel production. This paper will discuss Indonesia's nickel resources, reserves and production related to the distribution of locations, number of resources, number of reserves, grade, sustainability of reserves and their impact on the economy as well as efforts to maintain this sustainability. Previous articles only presented data on Indonesia's nickel reserves and production and an overview of global nickel. The data on nickel resources and reserves come from the 2021 inventory by the Geological Agency, which covers ore resources and reserves and their grades across several classifications. If there is no new data on reserve deposits or planned production rates, it is estimated that the ore reserves with nickel grades ≥ 1.7% will be depleted by 2036, while the ore reserves with Ni grades < 1.7% will be exhausted by 2056. Efforts to increase reserves include increasing exploration activities in brownfield areas, exploring remaining ultrabasic regions, and conducting detailed geological mapping of areas where ultrabasic rock is expected. Apart from raising the issue of the magnitude of nickel potential and mining value, this paper also discusses economic indicators in each nickel producing community using Gross Regional Domestic Product per capita. Based on the results of this analysis, it shows that there are differences in GDP per capita and the value of the mines owned by each region as a nickel producer. [ABSTRACT FROM AUTHOR]

When building 3D models of the subsurface, reconciling several geological and geophysical data of diverse nature, resolutions, coverage, or sensitivity, is challenging, both numerically and petrophysically. In this work, we propose a workflow for mapping selected geological features and characterise their uncertainty using a Bayesian Estimate Fusion algorithm. Different datasets such as 1D probabilistic models derived from geophysical data, drillholes and geological data are combined to produce probabilistic maps of selected geological boundaries, relying on petrophysical and geological assumptions. Leveraging large, high-quality geophysical datasets acquired in the eastern Gawler Craton in South Australia, we demonstrate the applicability of our approach with two examples: (1) we map in 3D the top of a stratigraphic unit in the cover, the Tregolana Shale, using 1D magnetotelluric (MT) and 1D Airborne Electromagnetic (AEM) probabilistic models, drill holes and surface geology; (2) we map the depth to basement using 1D probabilistic MT models, drill holes and interpreted structural information. Our results show that the different resolution, data sampling, depth of investigation and reliability of the utilised datasets can be combined in a complementary fashion, overcoming their respective limitations, to find solutions/models that satisfy all the datasets. We show that probabilistic workflows permit characterisation and reduce uncertainty when mapping the location of features of interest, but also permit the testing of geological hypotheses against other geophysical and geological data. These types of models are valuable to better characterise, interpret, and conceptualise the subsurface, enabling better exploration targeting and supporting efforts to discover new mineral deposits. [ABSTRACT FROM AUTHOR]

The Yerrida Basin in the south-eastern Capricorn Orogen, WA is a Proterozoic sedimentary basin that is prospective for base metals. A regional TEMPEST airborne electromagnetics (AEM) survey over the Capricorn Orogen, coinciding magnetotelluric (MT) survey and available downhole electrical property measurements provide an opportunity to compare the electrical conductivity of the rocks, and the electromagnetic (EM) responses of near surface and deeper sedimentary packages of the Yerrida Basin. Of particular interest is assessing whether it is possible to obtain reliable structural and stratigraphic information from, and to what depth, such as is required for exploration of basin terrains. The MT data were modelled using a 3D inversion algorithm, and the AEM data were modelling using a 1D inversion algorithm. An integrated interpretation of the two datasets allows surface geology to be mapped and for a conductivity section to be created to several kilometres depth. Electrical property measurements showed that one of the stratigraphic units, the Johnson Cairn Formation, is anomalously conductive and hence is readily mapped allowing faults, folds, thickness variations etc to be inferred from the inversions. The underlying and resistive Juderina Formation also gives rise to EM responses, albeit less strong. The results suggest significant modification of the published geological map of the area. The study demonstrates the usefulness of EM methods for exploring sedimentary terrains, but this is greatly facilitated by the presence of conductive stratigraphic units. While not always common practice in green fields exploration, it is recommended that electrical petrophysical measurements are made before committing to large scale EM surveys to better constrain interpretations. [ABSTRACT FROM AUTHOR]

The Meijiayan landslide in Pengshui County within Chongqing City is a medium-scale soil landslide triggered by the excavation of roadbeds. To delve into the influencing factors and assess the stability of this landslide, it is crucial to meticulously map the subterranean geological framework of the area. Such an analysis lays the groundwork for evaluating and mitigating the risks of future landslide instabilities. In this context, the semi-airborne transient electromagnetic method (SATEM), which is complemented by a receiving system mounted on an aerial platform, stands out as an innovative geophysical exploration technique. This method is adept at conducting swift measurements across complex terrains, making it particularly valuable for areas prone to such geological events. This paper presents the utilization of a cutting-edge loop source SATEM system, which was operationalized via a rotor-based unmanned aerial vehicle (UAV). The system was employed to conduct shallow geological structure detection experiments on the Meijiayan landslide. The SATEM detection outcomes have unveiled fluctuations in the electrical distribution across the upper strata, which are indicative of the subsurface geological boundaries, faults, and areas potentially rich in water within the landslide region. These discoveries affirm the viability of utilizing loop source SATEM for the identification of shallow geological structures in regions susceptible to landslides. The findings indicate that while the landslide is currently in a stable condition, it poses a significant risk of movement, especially during the rainy season, with the potential for landslides to be exacerbated by extreme or sustained rainfall events. [ABSTRACT FROM AUTHOR]

The use of the HVSR (Horizontal-to-Vertical Spectral Ratio) method on single-station microtremor measurements is well documented in small alluvial plains for bedrock mapping. In large sedimentary basins, like the Po Plain, its application is still debated. To shed some light on this issue, we investigated two seismogenic structures buried below the Po Plain Quaternary deposits: the Mirandola and Casaglia anticlines. We acquired and analysed a dense distribution of HVSR data covering the two areas and mapped the frequency and amplitude values of the observed resonance peaks. The top of both anticlines is highlighted by high amplitude peaks picturing E-W elongated sectors with high-impedance contrast, where Quaternary deposits are reduced in thickness to about 60–130 m and directly overlay the Pliocene (Mirandola) and Miocene (Casaglia) marine units. In Mirandola, the high-amplitude peaks also correspond to higher resonance frequencies, while in Casaglia, the distribution of resonance frequencies is relatively uniform suggesting a flatter crestal region and the lateral continuity of the resonance surface. The combination of peak frequency and amplitude information on a dense grid of measurement points is thus confirmed to be useful for identifying and mapping buried geological structures such as structural highs. Further modelling is being carried out to estimate the depth of the surface responsible for the observed resonances, through calibration with borehole information. [ABSTRACT FROM AUTHOR]

In recent decades, watersheds in the middle Himalayan belt have witnessed land degradation, flood, and landslide disasters. Growing population pressure, intensified use of watershed resources, and development activities—often alleged injudicious, have brought resource productivity and availability to the edge of unsustainability. The threat to precarious ecological balance, sustainable livelihood, and disaster risk is underpinning issues of densely populated Himalayan watersheds. Hence, understanding the essential physical characteristics of watersheds vis-à-vis human dimensions is essential for assessing and prioritizing the watersheds intended for ecological restoration, landslide and erosion control, and disaster risk reduction in upstream and downstream zones. Following these issues, this study using a geographical approach examines watershed variables representing susceptibility, hydrological and geomorphic response, land use, and human pressure to assess sub-watershed conditions and prioritize sub-watersheds. The study used high-resolution satellite imageries, digital elevation model, topographic and geological maps, rainfall and socioeconomic data from government sources to obtain the watershed variables. These variables were analyzed in the GIS platform. The leading variables and their relative importance were identified for assessing the watershed conditions by analyzing the correlation matrix, and AHP supported the expert judgment. These variables are mean basin slope, lineament density, drainage density, landslides, population density, and non-forest-forest ratio. The sub-watersheds condition of the Syangja District was assessed. The calculated overall vulnerability of sub-watersheds is positively related to susceptibility, poor land management, and human pressure index. The present study provided a methodological basis for assessing and prioritizing the watershed condition. [ABSTRACT FROM AUTHOR]

This study performed a representative elementary volume (REV) and 3D equivalent continuum study of rock fractures based on fluid simulations of 3D discrete fracture networks (DFNs). A series of 3D DFNs with heterogeneous aperture distributions (the DFN-H model) and uniform apertures (the DFN-I model) were established, in which the fractures were oriented according to the geological field mapping of a high-level radioactive waste candidate site in China. The 3D DFNs of the different model sizes were extracted and rotated in a number of directions to check whether there was a tensor quality of the permeability at a certain scale. The results show that aperture heterogeneity increases the REV size and results in a necessarily larger model size to reach an equivalent continuum behavior, and this effect is more obvious when the fracture density is smaller. The shape of the 2D permeability contour is irregular, with some breaks when the model size is small. As the model size increases, its shape gradually tends to become smooth and approaches an ellipse. The shape of the permeability contours of the DFN-H model is slender compared to the DFN-I model, indicating a larger difference between the minimum and maximum values of the permeability. For the DFN-H model, there is no appropriate approximation for the equivalent permeability tensor over the studied model size range, whereas a good fit of the permeability ellipsoid is obtained for the DFN-I model, and the 3D directional permeability is calculated at this model scale. The corresponding magnitude and direction of the principal permeability are obtained, which can be viewed as the equivalent permeability tensor for the approximated continuum medium. [ABSTRACT FROM AUTHOR]

Gravity measurements have uses in a wide range of fields including geological mapping and mine-shaft inspection. The specific application under consideration sets limits on the survey and the amount of information that can be obtained. For example, in a conventional gravity survey at the Earth's surface a gravimeter is translated on a two-dimensional planar grid taking measurements of the vertical component of gravity. If, however, the survey points cannot be chosen so freely, for example if the gravimeter is constrained to operate in a tunnel where only a one-dimensional line of data could be taken, less information will be obtained. To address this situation, we investigate an alternative approach, in the form of an instrument which rotates around a central point measuring the gravitational potential or its radial derivative on the boundary of a sphere. The ability to record additional components of gravity by rotating the gravimeter will give more information than obtained with a single measurement traditionally taken at each point on a survey, consequently reducing ambiguities in interpretation. We term a device which measures the potential, or its radial derivatives, around the surface of a sphere a gravitational eye. In this article we explore ideas of resolution and propose a thought experiment for comparing the performance of diverse types of gravitational eye. We also discuss radial analytic continuation towards sources of gravity and the resulting resolution enhancement, before finally discussing the possibility of using cold-atom gravimetry and gradiometry to construct a gravitational eye. If realised, the gravitational eye will offer revolutionary capability enabling the maximum information to be obtained about features in all directions around it. [ABSTRACT FROM AUTHOR]

Selecting the most effective prediction model and correctly identifying the main disaster-driving factors in a specific region are the keys to addressing the challenges of geological hazards. Fuyuan County is a typical plateau mountainous town, and slope geological hazards occur frequently. Therefore, it is highly important to study the spatial distribution characteristics of hazards in this area, explore machine learning models that can be highly matched with the geological environment of the study area, and improve the accuracy and reliability of the slope geological hazard risk zoning map (SGHRZM). This paper proposes a hazard mapping research method based on multisource remote sensing data extraction and machine learning. In this study, we visualize the risk level of geological hazards in the study area according to 10 pathogenic factors. Moreover, the accuracy of the disaster point list was verified on the spot. The results show that the coupling model can maximize the respective advantages of the models used and has highest mapping accuracy, and the area under the curve (AUC) is 0.923. The random forest (RF) model was the leader in terms of which single model performed best, with an AUC of 0.909. The grid search algorithm (GSA) is an efficient parameter optimization technique that can be used as a preferred method to improve the accuracy of a model. The list of disaster points extracted from remote sensing images is highly reliable. The high-precision coupling model and the single model have good adaptability in the study area. The research results can provide not only scientific references for local government departments to carry out disaster management work but also technical support for relevant research in surrounding mountainous towns. [ABSTRACT FROM AUTHOR]

The northern inlet channel to Jezero crater (Sava Vallis) terminates in a fan‐shaped depositional feature, part of which blends into the separate well‐known western fan delta that is the field site for the Mars 2020 mission's Perseverance rover. Jezero's northern fan potentially represents either a second fan delta within the crater or a distal portion of the western fan. To constrain the fluvial and sedimentological history of Jezero and place the rover's in situ observations in proper geologic context, we photogeologically map the northern fan deposits at a larger mapping scale than previous studies, using ground‐based imaging from the Perseverance rover for context. Fifteen map units are identified using HiRISE‐based interpretations of geologic characteristics and inferred processes as well as crosscutting relative age relationships. Mapped units are also defined based on orbital data from CRISM and THEMIS to assess their compositional signatures. We interpret the northern fan deposits as older than the uppermost blocky unit in the western fan delta, suggesting that they were deposited contemporaneously with or prior to the deposition of the western fan, and under similar climate conditions. The eastern portion of the northern fan deposits shows evidence of fluvial deposition from Sava Vallis, while part of its western side could represent a distal part of the western fan delta. We synthesize our interpretations to present scenarios for the deposition of the northern and western fans, which can help constrain the history of both watersheds and place it into context within the broader Isidis basin region. Plain Language Summary: The Mars 2020 Perseverance rover has primarily focused on using its scientific instruments to study the delta along Jezero crater's western margin. But there are fan‐shaped features that appear to originate from both the crater's western and northern channels ‐ Neretva Vallis and Sava Vallis, respectively. In this project, we compile orbital images, spectroscopy data sets, and images taken by the rover's Mastcam‐Z instrument to investigate whether the northern fan originated from the northern channel or is an outlying part of the western delta. Based on these observations and the geologic map created using them, we show that the northern fan deposits are older than the uppermost unit mapped in the western delta. We also demonstrate how the western portion of the northern fan deposits could be an outer part of the western delta, while the eastern portion may preserve material from Sava Vallis. We show that some units across the northern and western fans are the same or similar, making this work useful as the rover's mission continues. Finally, we present scenarios that could lead to what we see in Jezero today, helping us to understand the potential history of this area and the relationship between the northern and western watersheds. Key Points: Deposition of Jezero crater's northern fan predates that of its western fan blocky material—the western delta's uppermost surficial unitThe northern fan shows evidence of deposition from Sava Vallis, but part of its western region could be a distal part of the western deltaThe stratigraphic and depositional hypotheses presented provide context for the Mars 2020 mission and help constrain the history of both watersheds [ABSTRACT FROM AUTHOR]

The link between mantle plumes and the formation of large igneous provinces (LIPs) is well established although the anatomy of these remains equivocal. Recent experimental studies and geophysical data suggest that the mantle plume head is more likely to be irregular and asymmetric, rather than an axisymmetric flattened disk. The Emeishan large igneous province (ELIP) provides a unique opportunity to test this hypothesis. According to robust petrographic, geochronologic, and geochemical evidence from the late Permian basalts in the Sichuan Basin, and in conjunction with a comprehensive compilation of geologic maps and published geochemical data from the ELIP, we identified several giant radial "fingering" structures. Based on the shallow mantle source from the center to margin in the ELIP and relief of the lithosphere‐asthenosphere boundary, we propose a new mantle plume model to explain the evolution of the Emeishan plume periphery, where narrow finger‐like protrusions and plumelets developed outwards from the main body of the plume to the edges of the flattened plume head. Dragged fingers might have been torn apart into some plumelets, which dispersed and were trapped beneath the thinnest lithosphere relief, and eventually erupted to form small‐scale flood basalt in the Outer Zone of the ELIP. Key Points: The spatio‐temporal and geochemical characteristics of the Emeishan basalts in the Sichuan Basin are determinedThe Emeishan large igneous province developed fingering structuresA new model, that is, "fingering, torn apart and plumelets," may interpret the evolution of the mantle plume periphery and surface manifestation of the large igneous province [ABSTRACT FROM AUTHOR]

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1-Introduction The topography is, directly and indirectly, affects the geomorphic processes and hydrological behavior of the slope (Prancevic and Kirchner, 2019), therefore, quantitative correlation of topography features is possible due to deposition and runoff production and predicting the spatial distribution of soil and surface deposits (McKenzie and Ryan, 1999). different shapes and sides of slopes in the drainage basin affect the time of runoff movement on the slopes and drainage networks and the basin response, such as time, equilibrium, retardation time, concentration-time, and hydrograph peak time. These temporal features constitute an important part of the hydrological modeling of the watershed. Considering that most of rainfall-runoff models relate to runoff traverse times at the slopes surface, it is easy to study the topography effect on runoff features such as river discharge estimators, flood forecasting, peak flow, runoff volume, and water resource management (Merheb et al., 2016; Mlynski et al., 2019). In terms of morphodynamic conditions, the topography is directly related to erosion and sedimentation processes. Topographic wetness index theory (TWI) is designed as an important and all-purpose feature in the rainfall-runoff model to measure the effect and topography controlling on hydrological processes (Calogero et al., 2015; Jeziorska and Niedzielski, 2018; Xue et al., 2018). This model simulates the interaction of groundwater and surface water with topography to determine which regions are prone to saturation of the earth and thus have a high potential for surface accumulation water (Ballerine, 2017) and can be expressed quantitatively as a physical indicator the effect of the topography of watersheds slopes on the mechanism of substructure flow (groundwater), runoff production, the spatial distribution of soil moisture and the ability of soil moisture deficiency to saturation state at each point in the range and level of the basin. (Beven and Kirkby 1979; O'Loughlin 1986; Barling et al. 1994; Qiu et al., 2017). 2-Methodology The Maroon River drainage basin, with an area of 7228 square kilometers and an area of 802 kilometers, covers the central part of the Jarahi-Zohreh basin. The Jarahi-Zohreh basin is itself a large part of the Persian Gulf-Oman Sea basin, which its drainage network pours into the northwest part of the Persian Gulf (Fig. 1). In this study, the based data obtained have formed 30 m SRTM DEM data, 1:50000 topographic maps, geological maps of 1:100000, aerial photos, Landsat satellite imagery, Google Earth, and field visits and ArcGIS10.3, QGIS, and SAGA software. To estimate topographic indices, first, it is processed the DEM data file and the stream network of the study basin in the SAGA software environment and then topographic basin indices based on DEM data were calculated and analyzed by the existing functions of this software. In the continuation, slopes of the Maroon basin were classified into nine different types based on two indices of plan shape (divergence, convergence, parallel) and profile (curvature) slopes profile (concave, convex, and flat) (Fig. 2) and the obtained amount of TWI index was analyzed in them. a: The hydrological model (TOPMODEL) is a semi-distributed model where the topography changes of the region and participating levels play a major role in the runoff, assuming that hydraulic gradient can be estimated using the land topography gradient (Ballerine, 2017). The topographic information used in this model is introduced as a topographic moisture indicator and can express the topography effect on runoff production and slope movements quantitatively. These values are calculated using the digital elevation model (DEM) of the studied area and by measuring the flow direction, current accumulation, gradient, and different geometrical characteristics obtained from Arc Hydro software. The final result is a Raster layer which shows pathways (regions) with drainage ditches where water is likely to accumulate there (Ballerine, 2017). 3-Results The results of basin type stud show that the first-class waterways flow mostly in divergent basins with flat curvature. The second, third, and fourth classes of the basin flow in the concave and parallel basin, and the fifth and sixth classes flow in convex and convergent basins (Table 1). In divergent slopes of the basin, the topographic moisture index has been reduced and in convex and convergent basins, the topographic moisture index increases. Furthermore, the TWI index has a high inverse correlation with the degree gradient and average height of the river (-0.97). This index decreases with the increasing gradient and height of waterways (Table 2). In the trimming basins, the increasing general gradient has led to an acceleration of water flow, thus the time required for penetrating water flow and rainfalls is decreased and the concentration-time is decreased too, and correspondingly amount of erosion and water wasting is increased. 4-Discussion & Conclusions The results of the study show that the topographic features of the basin-like the slope plan and longitudinal profile of the slope play a decisive role in hydrological processes and runoff time features and slope response time. These features not only directly affect geomorphological and hydrological conditions like annual runoff, flood volume, soil erosion intensity, and sediment production, but also indirectly effects the climate, ecological situation, and vegetation, as well as effects on the water situation in the basin. The results of the basin slope type study are such that the divergent slopes are the lowest amount in the topographic moisture index. Surface water and subsurface water is not concentrated, they spread, and pass slopes water rapidly. the results showed that there is a significant relationship between hydrological processes with the topography and geomorphology indices and can be used as a variable to simulate the moisture state of the Maroon basin area, which is an example of an indirect and lowcost approach to study the hydrological and geomorphological features of the region. the consistency of this index to local soil conditions is a certain advantage over the existing methods and in detailed application programs it needs to perform more activity and perform adaptive studies. Therefore, knowledge of these indices and features in terms of impact on the variability of soil hydraulic features and surface Sediment is necessary to achieve sustainable development and reorganization of the region. [ABSTRACT FROM AUTHOR]

1-Introduction In recent years, the increasing trend of the population has caused urban areas to face a lot of physical development, the share of developing countries has been higher than that of developed countries. Physical development in many areas has caused rapid changes in land use and increased environmental degradation. Therefore, the physical development of cities is considered as one of the main factors that change the surface of the earth. Studies have shown that the urban areas of Iran, due to their unlimited and unplanned expansion, have encroached on the natural environments and destroyed them, which has increased the potential for natural hazards such as floods in these areas. Has been considering the mentioned cases, more supervision should be done on the physical development of cities, especially flood-prone cities. Saghez city in Kurdistan province is one of the flood-prone cities that have faced a lot of physical development in recent years. Due to its economic and social situation, this city has faced a large population growth in recent years, which has caused the significant physical development of this city and as a result, the development of residential areas into flood-prone areas. Considering the importance of the topic, in this research, the physical development of Saghez city towards flood-prone areas has been investigated. 2-Methodology In this research, in order to achieve the desired goals, descriptive-analytical methods have been used. The research data includes topographic maps 1:50000 and geological maps 1:100000, a digital elevation model of 30 meters, as well as Landsat satellite images (Table 1). Research tools include Arc GIS, ENVI and IDRISI. The models used in the research also include the integrated model of fuzzy and AHP (in order to identify flood-prone areas) as well as the LCM model (in order to evaluate the physical development process of Saghez city towards flood-prone areas). This research has been done in two stages. In the first stage, in order to prepare the flood potential map of the study area, 6 parameters of height, slope, slope direction, distance from the river, and type of lithology and land use have been used. In the second stage, in order to evaluate the process of physical development of Saghez city towards flood-prone areas, the LCM model has been used. At this stage, after preparing the land use maps, the prepared maps were entered into the IDRISI software and using the LCM model, the trend of land use changes in the study area was evaluated. 3-Results The results of the flood zoning of Saghez city have shown that the middle areas of the range have the highest flood potential due to the proximity to the Saghez River, low altitude and slope. Also, the results obtained from the satellite images have shown that the city of Saghez had an area of about 6.5 square kilometers in 1369, which increased by 1.1 square kilometers to 7.6 square kilometers in 2000. In continuation of the physical development process of this city, the area of residential areas increased to 10.2 and 16.6 square kilometers by 2019 and 2019, respectively. Based on this, the maximum amount of physical development with 5.5 square kilometers was related to the time period of 1389 to 1399. Also, the results of the physical development of cities towards flood-prone areas show that in 1369, 3.8 square kilometers of residential areas were exposed to the risk of flooding, and from this amount to 1379, 1389 and 1399, respectively, 3 It has increased by 4.1, 5.1 and 2.7 square kilometers. Based on this, the highest amount of development towards flood-prone areas with 1.9 square kilometers was related to the time period from 2010 to 2020. 4-Discussion & Conclusions The increasing trend of population and physical development of urban areas has caused a large part of population areas to move towards flood-prone areas in recent years. The results of this research have shown that the middle parts of the study area have a high flood potential due to their proximity to the river, low altitude and slope. The results of the evaluation of the physical development of the city of Saghez also indicate that this city has faced a lot of development during the years 1369 to 1399, and based on the results, the city of Saghez had an area of about 6.5 square kilometers in 1369, which is 2019 has increased to 16.7 square kilometers. The results of the evaluation of the physical development process of Saghez towards flood-prone areas indicate that in 1369, about 3.8 square kilometers were exposed to floods, which increased to 2.7 square kilometers in 1399. Also, the results of the evaluation of land use changes indicate that during the studied time period, 8.8 square kilometers of pastures, 0.6 of agricultural lands and 0.8 of pastures have been converted into residential areas, the highest amount of which is related to It was the eastern areas of Saghez city. According to the mentioned cases, a large part of the city of Saghez has moved towards flood-prone areas in recent years, which indicates the lack of monitoring of the physical development of this city. [ABSTRACT FROM AUTHOR]

Complex or compound landslides, which combine different movement types with sliding planes at various depths and with varying movement acceleration frequencies, are highly demanding for landform mapping, movement monitoring and reliable hazard assessment. In this work, several techniques including dendrogeomorphological investigation were combined to describe surface morphology, underground structures and movement dynamics of the compound and deep-seated landslide aiming to provide reliable information for its hazard assessment. Interpretation of high-quality digital elevation model and detailed field morphological mapping along with geological information provided context for the interpretation of electric resistivity tomography profiles and enabled the description of properties of two distinct landforms, which are typically identified on a compound or complex deep-seated landslides in the studied region—shallow slides and landslide blocks. Dendrogeomorphological investigation proved for the first time the movement accelerations of the landslide blocks, which reactivate approximately half as often as shallow slides. It also showed different trees' responses to the movements of these two landforms. Trees on the shallow landslide responded mainly with abrupt growth suppression (54.4%) to movements of its highly disturbed material. In contrast, trees on landslide blocks exhibited a dominant response (84.7%) with reaction wood to tilting of the landslide blocks composed of more coherent rock material. The research demonstrated that the dendrogeomorphological investigations provide reliable identification of years with accelerated movements, which corresponds well to instrumental, near-surface monitoring of the landslide. And at the same time, the method provided densely spatially distributed information about partial landslide reactivations during several decades in conditions (e.g. dense forests), where remote sensing methods are difficult to apply. Therefore, we argue that the dendrogeomorphological research is well applicable for hazard assessment of partial failures (cf., shallow slides and landslide blocks) of compound or complex landslides providing information also about the type of landslide movements (sliding vs. surface tilting) and character of the deformed material (highly disturbed vs. more coherent). [ABSTRACT FROM AUTHOR]

Shear zones are strain localization structures whose geometry and kinematics control the way how large crustal blocks are disposed and also provide important insights into the nature of pathways and deposition of ore forming fluids. Detailed geological field mapping, consolidated with meso- and micro-structural investigations, flow kinematics and finite strain analyses are fundamental tools to obtain information about the same. Formation, transport and precipitation of gold in major shear zone type gold deposits of the world, are also controlled by shearing activities. The Ramagiri-Penakacherla transcratonic shear zone system is characterized by NW-SE trending, 0.5 to 1 km wide shear zone, affecting both the Ramagiri-Penakacherla schist belt (RPSB) and surrounding granitoids. Sense of shearing is dominantly dextral and the main shear sense indicators include S-C fabric, down-dip stretching lineation, rotated quartz and feldspar porphyroclasts, drag folds, delta and sigma quartz porphyroclasts, bilaterally stretched quartz and feldspar porphyroclasts, and pinch-and-swell structures. Detailed kinematic and strain analyses were combined with vorticity estimates on rocks from these zone to document the patterns and geometry of deformation. The strain parameter measurements including strain ratio in the XZ principal plane of strain ellipsoid (RXZ), strain ellipsoid shape (K) and strain intensity (D) highlight a flattening strain shape of the strain ellipsoid. The shear zone is divided into three zones from its boundary to the center, depending on the amount of matrix and clast size viz. protomylonite, mesomylonite and ultramylonite. The quantitative kinematic analyses highlight that Wm varies between 0.774 to 0.89 for the protomylonite, 0.756 to 0.85 for the mesomylonite and 0.635 to 0.83 for the ultramylonite. This, in turn, indicate considerable proportion of pure shear, varying from 30% to 43% for the protomylonite, 35% to 45% for the mesomylonite and 38% to 56% for the ultramylonite (shear boundary to the center). Identification of pure shear component helped in explaining the varying width of the schist belt, along with its disappearance at punctuated intervals. Heterogeneous distribution of gold deposits in the RPSB is explained by better connectivity of the shear fractures in the mesomylonite and protomylonite zone (near the shear zone boundary) with lower strain than the ultramylonite zone (center of the shear zone), which facilitated better permeability for gold-bearing fluid pathways to flow and ultimate deposition. [ABSTRACT FROM AUTHOR]

The South Eastern Desert (SED) of Egypt is one of the most promising areas in Egypt; it is widely explored for exploring the rare earth elements (REEs) and uranium-bearing ores. It is a main part of the Arabian-Nubian Shield (ANS). Therefore, the present study concerns with Sikait-Nugrus area as one of the most prolific sites in this region. The study provides a detailed geological, structural, and mineralogical investigation of the monzogranites to describe and characterize the various alteration types and sequence. For this purpose, remote sensing, geochemical and petrographical techniques were applied. The remote sensing technique helped in constructing a detailed geologic map of the study area to follow up strictly the alteration zone of the Sikait-Nugrus area. Petrographically, the granites predominates in the study area, they are described as slightly and highly altered monzogranites. The slightly altered one is composed mainly of quartz (~ 20–35%), alkali feldspar (~ 25–30%), plagioclase (~ 25–30%), and mica (~ 5–15%), while accessory minerals are represented by zircon and monazite. On the other hand, the portion of this granite close to the shearing zone is intensively altered and characterized by sericitization as the main alteration processes. This sheared portion is characterized by accessory minerals as, uranothorite, allanite, fluorite and Nb-minerals (ishikawaite). Minerlogically, the altered monzogranites are predominated by the following mineral groups: (1) radioactive minerals as uranyl silicates (soddyite, uranophane and kasolite), and thorium minerals (thorite and uranothorite), (2) Nb–Ta minerals (betafite, plumbobetafite, columbite, fergusonite, and aeschynite), (3) REE minerals (monazite, cheralite and xenotime), and (4) zircon and fluorite as accessory minerals. Geochemically, the recorded pattern of the REEs tetrad effect (M-type) for the highly altered samples indicate that these granites are highly evolved and affected by late stage of hydrothermal alteration and the effective water-rich alteration processes that connected to intensive physico-chemical changes. The total REE concentrations equal 241.8 and 249.75 ppm for the highly and slightly altered samples. A significant mass change (MC) was analyzed by the isocon technique (22.95 & 11.11) and volume change (VC) (1.8 &-7.99) for the highly and slightly altered samples, respectively. The mass balance calculations and the isocon diagrams revealed that some major oxides were removed from the slightly altered monzogranites and transformed later into highly altered monzogranites with increasing the alteration intensity due to the impacts of hydrothermal alteration processes. The studied area is virgin, where no detailed studies have been applied to this region. It is extendable to other parts of the Arabian-Nubian Shield in around the Red Sea in Egypt, Sudan, Saudi Arabia and Yemen. The applied technical workflow is also extendible to other surface analogues everywhere. [ABSTRACT FROM AUTHOR]

Bedrock geology is crucial in structuring alpine plant communities. Old studies mainly focused on the compositional differences between alpine plant communities on carbonate rocks and crystalline rocks, i.e., calcareous vs. siliceous vegetation. Increasing attention is being paid to bedrock types other than calcareous or siliceous ones, viz. those which have intermediate geochemical characteristics between pure calcareous and pure siliceous ones. Among these types of 'intermediate' bedrocks, calc-schists and serpentines are generally characterized by vegetation comprised of a mixture of basiphilous and acidophilous species. We selected several sites in alpine grasslands in the Western Italian Alps, on calc-schist and serpentine bedrocks, located at 2500 ± 100 m above sea level. X-ray fluorescence quantification of major and trace elements, combined with stereomicroscopic examination of bedrock samples with a petrographic approach, revealed a much broader range of bedrock types than recognized by inspection of geological maps. The vegetation investigated in our study was mostly composed of a set of species found more or less frequently in alpine silicicolous or calcicolous plant communities of the Alps and other European mountains. The carbonate content in the bedrock was one of the main drivers of variation in grassland vegetation, not necessarily related to soil pH. There were no distinctive species uniquely characterizing grassland vegetation on serpentines or calc-schists. [ABSTRACT FROM AUTHOR]

The information obtained from direct data (geological mapping and boreholes) and indirect techniques (reflection seismology, time-domain electromagnetics and magnetometry) is combined to analyse the northern limit of the Bailén basin (southeastern Spain). This Triassic–Neogene basin is confined by a graben-type structure, limited by two normal faults in the SW–NE direction (the Baños de la Encina-La Carolina fault and Guarromán fault). The movement of these faults was complex, with different pulses occurring over time. Therefore, the subsidence of the basin and the sedimentary filling of the graben were different, giving rise to lateral changes in the facies and thicknesses. This study focuses on the Baños de la Encina fault, chosen as the experimental site to analyse the effectiveness and accuracy of these geophysical techniques to reveal the basement structure and geometry. Seismic reflection allows to detect two faults that caused the subsidence of the eastern sector of the graben. The TDEM method made it possible to calculate the depth of the Palaeozoic basement, as well as reveal the presence of the two aforementioned faults. Magnetic total field data highlight variations in the basement depth that can be used to infer previously unknown fractures, in this case, in the NW–SE direction. [ABSTRACT FROM AUTHOR]

The Holy Monastery of Panagia Spiliani is an important religious monument of the Aegean islands. The monastery is built on a steep rocky hill in the Castle of Mandraki on Nisyros island. On the slopes of the foundation area of the monastery, landslides have occurred in the past, mainly rockfalls and slides, while the risk of new similar phenomena in the future is high. To assist the geohazard assessment and mitigation design works, a combined survey using Terrestrial Laser Scanning (TLS) and Unmanned Aerial Vehicle (UAV) photogrammetry was implemented. Besides capturing the detailed morphology within high-resolution 3D point clouds, the main engineering geological units were identified on the slopes, while critical structural ground elements and unstable blocks were mapped in detail. These were quantified in terms of geotechnical parameters, and the engineering geological model of the hill was finalised and presented in an engineering geological map and cross sections. The mitigation measures are targeted towards the stabilisation of the wider area of the upper slope, hence the stability of the monastery and its surroundings risk elements, as well as the support of specific, large- to small-scale unstable rock blocks on the whole slope area, securing accessibility to the main beach of the village. [ABSTRACT FROM AUTHOR]

The Mineral King pendant is an ~15-km-long, northwest-striking assemblage of Permian to mid-Cretaceous metavolcanic and metasedimentary rocks that form a steeply dipping wall-rock screen between large mid-Cretaceous plutons of the Sierra Nevada batholith (California, USA). Pendant rocks are generally well layered and characterized by northwest-striking, steeply dipping, layer-parallel cleavage and flattening foliation and steeply northwest-plunging stretching lineation. Northwest-elongate lithologic units with well-developed parallel layering and an absence of prominent faults or shear zones suggests a degree of stratigraphic continuity. However, U-Pb zircon dating of felsic metavolcanic and volcanosedimentary rocks across the pendant indicates a complex pattern of structurally interleaved units with ages ranging from 277 Ma to 101 Ma. We utilize a compilation of 39 existing and new U-Pb zircon ages and four reported fossil localities to construct a revised geologic map of the Mineral King pendant that emphasizes age relationships rather than lithologic or stratigraphic correlations as in previous studies. We find that apparently coherent lithologic units are lensoidal and discontinuous and are cryptically interleaved at meter to kilometer scales. Along-strike facies changes and depositional unconformities combine with kilometer-scale tight folding and structural imbrication to create a complex map pattern with numerous discordant units. Discrete faults or major shear zones are not readily apparent in the pendant, although such structures are necessary to produce the structural complications revealed by our new mapping and U-Pb dating. We interpret the Mineral King pendant to be structurally imbricated by a combination of kilometer-scale tight to isoclinal folding and cryptic faulting, accentuated by, and eventually obscured by, pervasive flattening and vertical stretching that preceded and accompanied emplacement of the bounding mid-Cretaceous plutons. Deformation in the Mineral King pendant represents a significant episode of pure-shear-dominated transpression between ca. 115 Ma and 98 Ma that adds to growing evidence for a major mid-Cretaceous transpressional orogenic event affecting the western U.S. Cordillera. [ABSTRACT FROM AUTHOR]

Since the 2015 Gorkha earthquake in Nepal, the relationship between the geometry of megathrusts and the control it exerts over the nucleation and propagation of major earthquakes has become an important topic of debate. In this study, we integrate new geologic mapping, a newly interpreted cross section from the Daraundi valley of central Nepal, two published cross sections from the neighboring Marsyangdi and Budhi Gandaki valleys, and a suite of 270 thermochronometric ages to create an integrated and validated three-dimensional kinematic model for the central Nepal Himalaya. We use this model to investigate the assertion that the westward propagation of the Gorkha rupture was restricted by deep-seated structures in the Main Himalayan thrust. The integrated kinematic model based on these cross sections indicates that the ~30 km southward step in the Main Central thrust system mapped in the Daraundi valley, along with the corresponding step in the distribution of reset muscovite (Ar-Ar) ages, is not the result of a lateral structure in the modern Main Himalayan thrust. Instead, the step in the surface geology is the result of a considerably shorter Trishuli thrust sheet in the Daraundi transect (~30 km compared to between 105 and 120 km in the other transects). The corresponding southward step in the distribution of reset muscovite Ar-Ar ages is the result of the Lesser Himalayan duplex being completely translated over the Main Himalayan thrust ramp, elevating and exposing rocks heated to >400 °C farther south in the Daraundi transect. Our integrated model also highlights the 10–15 km of out-of-sequence thrusting that occurs on the Main Central thrust system across central Nepal. Importantly, these out-of-sequence thrusts sole directly into the modern Main Himalayan thrust ramp, and, together with the distribution of reset zircon (U-Th)/He and apatite fission track ages, show that the modern ramp is distinctly linear from east to west, with no support for a lateral structure at the ramp or to the south. [ABSTRACT FROM AUTHOR]

The latest geological and geophysical information on the Zeya-Bureya sedimentary basin (Russia, Far East) is summarized. Based on drilling data from corehole and deep wells and 2D and 3D CDPM seismic data, taking into account the integrated interpretation of gravity and magnetic survey data and geological survey materials, a map was compiled for the surface of the pre-Mesozoic basement of the sedimentary basin, as well as structural maps for the top of the Cretaceous formations. The maps reflect a series of rift grabens and uplifts identified by the authors on seismic time sections during their reinterpretation. The method of compiling maps is given. A geological map of sediments overlying the pre-Mesozoic basement of the Zeya-Bureya sedimentary basin and a tectonic map of the sedimentary cover were compiled. During tectonic zoning of the sedimentary cover, the classification of tectonic elements was adopted that is widely used in the tectonic zoning of oil and gas regions, proposed by V.D. Nalivkin and updated at the Trofimuk Institute of Oil and Gas Geology and Geophysics, Siberian Branch, Russian Academy of Sciences (INGG SB RAS). As a result of tectonic zoning in the basin, the Inner Region and the Outer Belt were identified, and the tectonic elements complicating them were characterized. A characteristic feature of the Outer Belt is the presence of large intermediate structures: monoclines and mega- and mesomonoclines. Conversely, the Inner region of the basin is characterized by the presence of a large negative structure, complicated by smaller positive and negative elements. The main stages of the formation and development of the sedimentary cover of the Zeya-Bureya sedimentary basin are identified and described: rifting, early syneclise, late syneclise, and neotectonic. [ABSTRACT FROM AUTHOR]

The Neotethyan Sanandaj–Sirjan Zone of western Iran has recorded major magmatic activities due to its continental arc tectonic setting during the Mesozoic. The Varcheh mafic intrusions were less‐studied plutons in the northern Sanandaj–Sirjan Zone (SSZ). Field evidence, petrography, geochemistry and U–Pb geochronological data were used to determine petrographic composition, geochemical nature, crystallization age and also to suggest a conceptual tectonomagmatic model for their emplacement. Small plutonic bodies are dominantly composed of monzogabbro that have intruded into the Cretaceous sedimentary rocks. Based on U–Pb zircon datings, these rocks have crystallized at 125–118 Ma in late Early Cretaceous (Barremian–Aptian), and are older than the supposed ages reported on geological maps. Varcheh rocks are not just typical calc‐alkaline rocks and some show alkaline affinity. Negative anomalies in Nb–Ta–Ti and enrichments in some large‐ion lithophile elements on spider diagrams are consistent with a subduction‐zone setting. Potential deep source for magma generation is partial melting of subcontinental lithospheric mantle wedge above a subducting slab of oceanic lithosphere. The spaces for the Varcheh mafic intrusions are accommodated by dominant dextral strike‐slip movement in a continental arc experiencing extension during late Early Cretaceous subduction. According to the zircon U–Pb geochronology results in this paper and previous U–Pb ages in the northern part of the SSZ, the mid‐Cretaceous magmatism reveals a significant NW‐ward younging trend and migration of the magmatic arc from the Barremian–Aptian in south‐east to the Albian–Cenomanian in the north‐west. [ABSTRACT FROM AUTHOR]

The main aim of the study is to perform a high-precision mapping of geological features (lineaments and faults) using advanced gravity processing methods. The main techniques used for gravity data processing are the tilt angle of horizontal gradient (TAHG), the improved logistic filter (ILF), the fast sigmoid edge detector filter (FSF), and an edge detection filter based on the arcsine function (ASF). Before applying these edge detection filters to major geological units of North Cameroon, their effectiveness and performance have been assessed on synthetic gravity data and on random noise incorporated synthetic data. In addition, the Euler deconvolution has been used to estimate the position and depth of anomalous gravity sources in the study region. Using these edge detection techniques, a precise mapping of structural lineaments in the region has been established. It appears that the main structural features are trending along the N-S, NNE-SSW and NE-SW directions. The deepest density anomalies in the region are identified in the NW–SE direction, which coincides well with the extension of the Central and West African rift system in the study area. The advanced edge detection techniques and the Euler deconvolution method have both identified a network of superficial lineaments around longitude 13oN and latitude 8oN, and located between 0 and 4 km depth. The NW–SE trending crustal features outlined in the northeast of the region indicate that the area would have been the target of a uniform tectonic activity. This study is crucial to improve the knowledge of the configuration of fractures network, and to a better exploitation of groundwater resources available in the region. [ABSTRACT FROM AUTHOR]

Remote sensing observations represent the primary means in the production of geologic maps of planetary surfaces. However, they do not provide the same level of detail as Earth's geologic maps, which rely also on field observations and laboratory analyses. Color‐derived basemaps can help to bridge this gap by highlighting peculiar surface and compositional properties. Here, we analyzed the spectral properties of the lunar Tsiolkovskiy crater through the definition of spectral units summarizing the information enclosed by a set of selected spectral parameters. We then performed a compositional analysis of the newly derived spectral units that helped us in discriminating the presence and relative abundance of the main mineralogical phases on the Moon. As a final step, we produced a geo‐stratigraphic map of the Tsiolkovskiy crater integrating in a single mapping product both morphologic, stratigraphic and compositional information. The basaltic infilling of the crater is distinguished by three spectral units associated with distinct effusive events presenting a different composition. On the central peak, plagioclase and olivine suggest the presence of Mg‐suite rocks from the lower crust. The continuous ejecta deposits are mostly characterized by impact melts and shocked materials rich in glass or agglutinates related to more mature terrains from which occasionally appear fresher anorthositic and gabbroic outcrops exposed by the inward sliding of the crater walls. Overall, the geo‐stratigraphic map allows inferring compositional variations associated with the different morpho‐stratigraphic units, which clarify and elaborate on the compositional heterogeneities within the lunar crust and the Tsiolkovskiy crater, and its geologic evolutionary history. Plain Language Summary: The main data used to produce geologic maps of planetary surfaces come from orbiting missions. However, geologic maps of Earth provide much more information, relying also on observations made on the field and analyses made in the laboratory. Color images derived from the combination and processing of spectral information can help to make planetary maps more comprehensive, similarly to the Earth's ones, by drawing attention to surface and compositional aspects. In this work, we performed a spectral and compositional study of the Tsiolkovskiy crater on the Moon which enabled us to distinguish the presence and relative quantity of the most common minerals constituting the lunar rocks. We also produced a geo‐stratigraphic map coupling the information about the surface textures and shapes, relative time of deposition, and composition. On the basaltic floor, we discriminated the presence of three different spectral characteristics correlated with a sequence of flooding events showing distinct properties and a central peak exhibiting rocks emerged from the lowest strata of the lunar crust. The continuous ejecta blanket, instead, is characterized by mature materials interspersed by fresher exposures of subsurface materials. To conclude, the new mapping product allows an in‐depth interpretation of the geologic evolution of the Tsiolkovskiy crater. Key Points: Production of a 10‐unit Spectral Units map conveying the spectral and compositional properties within the Tsiolkovskiy craterIntegration of geologic and spectral units to produce a more comprehensive mapping product, namely a geo‐stratigraphic mapElaboration on the geological and compositional evolution of our study area [ABSTRACT FROM AUTHOR]

Machine learning and remote sensing techniques are widely accepted as valuable, cost-effective tools in lithological discrimination and mineralogical investigations. The current study represents an attempt to use machine learning classification along with several remote sensing techniques being applied to Landsat-8/9 satellite data to discriminate the various outcropping lithological rock units at the Duwi Shear Belt (DSB) area in the Central Eastern Desert of Egypt. Multi-class machine learning classification, multiple conventional remote sensing mapping techniques, spectral separability analysis based on the Jeffries-Matusita (J-M) distance measure, fieldwork, and petrographic investigations were integrated to enhance the lithological discrimination of the exposed rock units at DSB area. The well-recognized machine learning classifier (Support Vector Machine—SVM) was adopted in this study, with training data determined carefully based on enhancing the lithological discrimination attained from various remote sensing techniques of False Color Composites (FCC), Principal Component Analysis (PCA), and Minimum Noise Fraction (MNF), along with the fieldwork data and the previously published geologic maps. High overall accuracy of the SVM classification was obtained, however, inspection of the individual rock unit classes' accuracies revealed lower accuracy for certain types of rock units which were also found associated with lower separability scores as well. Among the least separable rock units were; metagabbro rocks that showed high spectral similarity with the volcaniclastic metasediments rocks, and the metaultramafics of the ophiolitic mélange showed spectral attitude of high correlation to that of the Hammamat volcanosedimentary rocks. Target-oriented Color Ratio Composites (CRC) technique was implemented to better discriminate these hardly separable rock units. A final integrated geological map was obtained comprising the various discriminated Neoproterozoic basement rock units of the DSB area. The successfully mapped litho-units include; Meatiq Group (amphibolites, gneissic granitoids, and mylonitized granitoids), ophiolitic mélange (metaultramafics, metagabbro-amphibolites, and volcaniclastic metasediments), Dokhan volcanics, Hammamat sediments, and granites. An adequate description of these rock units was also given in light of the conducted intense fieldwork and petrographic investigations. [ABSTRACT FROM AUTHOR]

Geological mapping involves the identification of elements such as rocks, soils, and surface water, which are fundamental tasks in Geological Environment Remote Sensing (GERS) interpretation. High-precision intelligent interpretation technology can not only reduce labor requirements and significantly improve the efficiency of geological mapping but also assist geological disaster prevention assessment and resource exploration. However, the high interclass similarity, high intraclass variability, gradational boundaries, and complex distributional characteristics of GERS elements coupled with the difficulty of manual labeling and the interference of imaging noise, all limit the accuracy of DL-based methods in wide-area GERS interpretation. We propose a Transformer-based multi-stage and multi-scale fusion network, RSWFormer (Rock–Soil–Water Network with Transformer), for geological mapping of spatially large areas. RSWFormer first uses a Multi-stage Geosemantic Hierarchical Sampling (MGHS) module to extract geological information and high-dimensional features at different scales from local to global, and then uses a Multi-scale Geological Context Enhancement (MGCE) module to fuse geological semantic information at different scales to enhance the understanding of contextual semantics. The cascade of the two modules is designed to enhance the interpretation and performance of GERS elements in geologically complex areas. The high mountainous and hilly areas located in western China were selected as the research area. A multi-source geological remote sensing dataset containing diverse GERS feature categories and complex lithological characteristics, Multi-GL9, is constructed to fill the significant gaps in the datasets required for extensive GERS. Using overall accuracy as the evaluation index, RSWFormer achieves 92.15% and 80.23% on the Gaofen-2 and Landsat-8 datasets, respectively, surpassing existing methods. Experiments show that RSWFormer has excellent performance and wide applicability in geological mapping tasks. [ABSTRACT FROM AUTHOR]

Areas with potential to host clay deposits in Las Tunas province were identified by combining remote sensing data and geological information integrated in the Geographic Information System (GIS). Geological mapping, remote sensing and geospatial modeling techniques were used. The findings reveal a heterogeneous distribution of areas with moderate, high and very high potential to host clay deposits throughout the region, with significant concentrations in Manatí, Tunas, Jobabo, Colombia and Amancio municipalities. The integration of remotely sensed data and geological sources in a GIS environment are effective and feasible for this type of analysis. [ABSTRACT FROM AUTHOR]

During the sampling of a stratigraphic section along the shore of the Fiastra Lake (Carg Project - Sheet 313 “Camerino” of the Geological Map of Italy at 1:50 000 scale), a small rock boulder with partially exposed bony material was discovered at the base of a small cliff at the northern termination of the Sibillini Mts. In this area, the classical facies of Umbria-Marche stratigraphic succession are well-exposed. The Oligocene-Miocene portion of the succession is represented by the ~200 m-thick Scaglia Cinerea Formation, passing upwards to the ~100 m-thick Bisciaro Formation. The microfossil assemblage has allowed the specimen to be constrained to the lower Burdigalian. The skeletal remains were examined using a CT-SCAN, a non-invasive method that has proven to be highly performing. The analysis revealed some articulated vertebrae, deformed by lithostatic compaction, which are attributed to a shark of the order Lamniformes. Subsequently, the vertebrae were digitally isolated, extracted from the surrounding matrix, and rendered into three-dimensional prints. Through digital retro-deformation, the body length of the lamniform shark was estimated to be approximately 4 metres. Further considerations on the vertebrae allowed us to infer that the studied shark had similarities to either Isurus oxyrinchus Rafinesque, 1810 or Carcharodon carcharias Linnaeus, 1758. The development of a dead-fall microbial community likely facilitated the preservation of the vertebrae. The studied specimen represents the first occurrence of a lamniform shark in the Lower Miocene of the Umbria-Marche Domain and represents one of the very rare recorded occurrences of lamniforms from the Lower Miocene of Italy [ABSTRACT FROM AUTHOR]

Apart from within the Arumbera Sandstone that spans the Ediacaran–Cambrian boundary, the entire Neoproterozoic succession of the Amadeus Basin has been generally believed to be devoid of metazoan fossils, despite features of possible biogenic origin having been described in the earliest geological mapping reports. Herein are described a suite of curious, rounded impressions preserved upon the surface of a sandstone bed from the basal Neoproterozoic unit, the quartzitic Heavitree Formation that dates to ca 850 Ma. Compared with rounded structures of both organic and inorganic origin, these features resemble fossils of stranded medusae, both modern and ancient, and thereby add a potentially pelagic lifeform to previously described burrowing and sessile forms of likely metazoans, which are preserved as fossils/trace fossils within the Tonian period of the Neoproterozoic elsewhere in the basin. An organic origin for these features would support the contention that the Amadeus Basin harbours the earliest evidence that macroscopic life flourished, albeit briefly, some 215 million years prior to the start of the Ediacaran period and 250 million years before metazoans successfully colonised the late Ediacaran seas. Curious rounded impressions upon a scree sample of Heavitree Formation (ca 850 Ma) are best compared with fossils of stranded jellyfish, both modern and ancient. Such impressions add to the phyla seemingly extant within the Amadeus Basin during the Tonian Period (early Neoproterozoic). Such phyla suggest that metazoan life evolved some 250 Ma earlier than generally believed, although became extinct locally some 10 Ma later. Extinction occurred at ca 840 Ma when changing climate caused the enclosed Amadeus Basin to evolve from conducive shallow aquatic conditions to a harsh evaporitic salt pan. Two later forays into metazoan evolution within the basin are evidenced by burrow-like tubular structures at ca 720 Ma and the Arumberia fossils at ca 560 Ma. [ABSTRACT FROM AUTHOR]

The Elat/Timna area in Southern Israel provides an unparalleled opportunity for geological field studies due to its unique geology, spanning from the Neoproterozoic to the Holocene. The well-exposed rocks document the variability and evolution of three major processes: the creation of the Arabian-Nubian Shield during the Neoproterozoic, the accumulation of the Cambrian to Eocene sedimentary sequence, and the Miocene to Recent evolution of the Dead Sea Transform, an active plate boundary. The area's geological diversity and extensive documentation of its geology have made it a particularly important study site for geoscience students. Recently the Geological Survey of Israel published new 1:50,000 scale geological maps of the area, updated by additional fieldwork and presented in a series of reports. This paper presents a brief geological overview and a description of six key locations, complete with maps and photos that are a showcase document to the area's geological uniqueness as an excellently-exposed window into 800 million years of Neoproterozoic to Holocene evolution at the NE African plate. [ABSTRACT FROM AUTHOR]

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The country of Iran is part of the Alpine-Himalayan orogeny belt and is divided into different tectonic seismic states. Based on the classification of tectonic seismic states, Kerman province is located in the central Iran zone. The city of Hojedk is also located in the seismic state of central Iran, which is in a relatively high-risk zone in terms of seismicity and has experienced large earthquake events. In this research, for the first time, the city of Hojedk has been comprehensively investigated in terms of seismic conditions to facilitate the decision-making process for preventive measures, especially the improvement and strengthening of buildings against earthquakes. In this research, data from the catalog of earthquakes of the University of Tehran's Geophysics Institute were used to analyze the earthquake hazard, and geological maps of the Geological Organization were used in the geological surveys and faults in the area. Earthquake hazard analysis in Hojedk City has been done in a probabilistic way. In this method, seismic springs have been identified and determined for the area. The information on the faults in the region and the earthquake catalog have been used for this research stage. At this stage, seismic springs are considered regionally. After determining the seismic springs, the seismic parameters were calculated and then the strong ground motion was estimated and finally, the earthquake hazard analysis was done by combining the uncertainties in the earthquake position and the magnitude of the strong ground motion parameters in the specific time period. The city of Hojedk is placed in a very high seismic risk zone. Major earthquakes have occurred in the area of this city. Due to geology, this city is located on the Shemshak, Badamo, Hojedk and Shotori formations. There are many faults in the city of Hojedk, the closest fault to this city is the Deh Zana fault. The length of this fault is 18 km and its mechanism is thrust. The area of Hojedk City is an active area in terms of the occurrence of earthquakes. In this area, 6 historical earthquakes have occurred, the largest of which occurred with a magnitude of 6.1 in 1897. Historical earthquakes are in the large range and the smallest of them has a magnitude of 5.5. 4141 earthquakes occurred in the range from 1900 to 2023, of which 4 earthquakes occurred in this time range with a magnitude of 6 or more. 8 seismic springs of regional type were identified based on the trend of faulting and accumulation of earthquakes in Hojedk city. Research on aftershocks has shown that the number of events with a magnitude of about 3.4 to 5 is the highest, and the depth of most earthquake events is between 10 and 20 kilometers. The seismic coefficients a, and b calculated in this range are 0.86 and 3.88, respectively. The seismicity rate in the studied area for magnitude 4 and greater is 1.47. The hazard analysis of the area for the return period of 475 years shows that the maximum acceleration of the bedrock in the area is 0.45, which is in the area of Hojedk city is 0.25-0.35. The acceleration map shows that the highest accelerations are in the northwest-southeast trend, which is in good agreement with the trend of the faults. Therefore, in terms of construction laws, the studied area is of special importance, so by having soil boreholes in the area, seismic micro zoning can be done and its results can be used to improve construction and select and use materials. [ABSTRACT FROM AUTHOR]

The Beiluo River Basin, situated in the central region of the Loess Plateau, frequently experiences landslide geological disasters, posing a severe threat to local lives and property. Thus, establishing a detailed database of historical landslides and analyzing and revealing their development characteristics are of paramount importance for providing a foundation for geological hazard risk assessment. First, in this study, landslides in the Beiluo River Basin are interpreted using Google Earth and ZY-3 high-resolution satellite imagery. Combined with a historical landslide inventory and field investigations, a landslide database for the Beiluo River Basin is compiled, containing a total of 1781 landslides. Based on this, the geometric and spatial characteristics of the landslides are analyzed, and the relationships between the different types of landslides and landslide scale, stream order, and geomorphological types are further explored. The results show that 50.05% of the landslides have a slope aspect between 225° and 360°, 68.78% have a slope gradient of 16–25°, and 38.97% are primarily linear in profile morphology. Areas with a high landslide density within a 10 km radius are mainly concentrated in the loess ridge and hillock landform region between Wuqi and Zhidan Counties and in the loess tableland region between Fu and Luochuan Counties, with a significant clustering effect observed in the Fu County area. Loess–bedrock interface landslides are relatively numerous in the northern loess ridge and hillock landform region due to riverbed incision and the smaller thickness of loess in this area. Intra-loess landslides are primarily found in the southern loess tableland region due to headward erosion and the greater thickness of loess in this area. Loess–clay interface landslides, influenced by riverbed incision and the limited exposure of red clay, are mainly distributed in the northern part of the southern loess tableland region and on both sides of the Beiluo River Valley in Ganquan County. These results will aid in further understanding the development and spatial distribution of landslides in the Beiluo River Basin and provide crucial support for subsequent landslide susceptibility mapping and geological hazard assessment in the region. [ABSTRACT FROM AUTHOR]

Text Landslides are one of the types of large-scale processes that cause many human and financial losses in many parts of Iran and the world every year. The increase in population and the expansion of human settlements in mountainous areas, the difficulty of predicting the occurrence of landslides and the numerous factors influencing the occurrence of this phenomenon, reveal the necessity of landslide risk zoning. Identifying the effective factors in the occurrence of this phenomenon and its risk zoning is one of the basic and practical methods to achieve its forecasting, control and monitoring solutions. By using field studies, geological and topographical maps, and by reviewing the researches and studies done in this field, as well as examining the existing conditions in the studied area, 9 factors of elevation, slope, slope direction, lithology, distance from the fault., the distance from the river, the distance from the communication roads, land use and rainfall were investigated as factors affecting the occurrence of landslides. Therefore, the purpose of this research is to investigate and analyze the most important factors involved in creating the risk of landslides in Garami city and to identify the prone areas that will probably be involved in landslides in the near future. In this research, the zoning of prone areas was done with the Aras multicriteria algorithm in the Edrisi software environment, and according to the results of landslide risk zoning; The criteria of land use, slope, and lithology are the most important factors involved in creating the risk of landslides in the study area with weight coefficients of 0.187, 0.152, 0.152, and 0.142, respectively, and are 361.99 and 450.32, respectively. A square kilometer of the area has a very high probability of danger. Finally, it can be said that the most important factor involved in increasing the amount and potential of landslides in Germi city is the change of land use and the increase of agricultural land and livestock pastures. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive assessment of the geomorphology, crater distributions, and tectonic structures within Enceladus' cratered terrains. We analyzed the distributions of impact craters and tectonic structures in seven regions of interest to inform an interpretation of the geological history of this terrain in the context of Enceladus' global evolution. We found that the tectonic structures, including both ancient, subdued troughs and young, narrow fractures, point to a cratered terrain that not only experienced early tectonic modification but also shows evidence of recent geological activity. Ancient troughs present in the equatorial cratered terrains are similar in scale and orientation to troughs present in the Leading and Trailing Hemisphere Terrains, an observation that supports possible non‐synchronous rotation of the ice shell. A dearth of impact craters in the equatorial regions as identified previously does not hold for craters <3 km in diameter in the anti‐Saturnian hemisphere. The anomalous presence of excess small craters in this region could be due to secondary or sesquinary impacts from a catastrophic event occurring at Enceladus or a neighboring moon. Finally, narrow fractures are pervasive across the cratered terrains and are most commonly oriented parallel or sub‐parallel to the most proximal cratered terrain boundary. This directionality of pervasive recent fracturing could be related to the vertical movement of an isostatically uncompensated ice shell. Enceladus' cratered terrains provide insight into the long‐term evolution of the satellite, an important component to assessing its role in Solar System evolution and its potential for habitability. Plain Language Summary: We present a comprehensive characterization of the oldest terrain on Enceladus, the cratered terrains. We evaluated structural features and impact craters on the surface, including their morphology and spatial distributions. This analysis informs how we interpret the formation and change of these surface features in the context of how Enceladus as a whole has changed over time. We found that there are two main types of tectonic structures in the cratered terrains, including one set of relatively old troughs and at least one set of narrow fractures that is very young. This finding indicates that not only have the cratered terrains experienced early tectonic activity, but were also active recently. The ancient set of troughs are similar to those present in younger terrains on Enceladus, suggesting that the ice shell has rotated relative to its tidally locked position about Saturn. The comparatively young, narrow fractures in the cratered terrains are widespread and could have formed due to a vertically shifting ice shell. Enceladus' cratered terrains provide insight into what long‐term changes have taken place on the surface, an important component to understanding how Enceladus fits into Solar System formation and its past or present potential to host life. Key Points: Systematic review of Enceladus' cratered terrains results in a stratigraphic framework for geologic mapping and age determinationTroughs in the equatorial cratered terrains are similar to tectonized equatorial regions, suggesting non‐synchronous ice shell rotationAncient, subdued troughs and young, narrow fractures point to a cratered terrain that experienced both early and recent tectonic activity [ABSTRACT FROM AUTHOR]

This paper aims to achieve bedrock geologic mapping in the overburden area using big data, distributed computing, and deep learning techniques. First, the satellite Bouguer gravity anomaly with a resolution of 2'x2' in the range of E66°E96°, N40°-N55° and 1:5000000 Asia-European geological map are used to design a dataset for bedrock prediction. Then, starting from the gravity anomaly formula in the spherical coordinate system, we deduce the non-linear functional between rock density ρ and rock mineral composition m, content p, buried depth h, diagenesis time t and other variables. We analyze the feasibility of using deep neural network to approximate the above nonlinear generalization. The problem of solving deep neural network parameters is transformed into a non-convex optimization problem. We give an iterative, gradient descentbased solution algorithm for the non-convex optimization problem. Utilizing neural architecture search (NAS) and human-designed approach, we propose a geological-geophysical mapping network (GGMNet). The dataset for the network consists of both gravity anomaly and a priori geological information. The network has fast convergence speed and stable iteration during the training process. It also has better performance than a single neural network search or human-designed architectures, with the mean pixel accuracy (MAP) = 63.1% and the frequency weighted intersection over union (FWIoU) = 42.88. Finally, the GGMNet is used to predict the rock distribution of the Junggar Basin. [ABSTRACT FROM AUTHOR]

With this study, our aim was to estimate the nutrient fluxes relevant for assessing nutrient sustainability as accurately as possible and to calculate nutrient balances for alternative forest management scenarios. Furthermore, we tested whether mapping units from existing geologic maps can serve as a basis for forest practitioners to estimate nutrient sustainability or whether more detailed data are needed. Positive fluxes include deposition and weathering, while negative fluxes include losses due to leaching and nutrient removal through timber harvesting in the balance. Weathering and leachate losses were modeled with a geochemical model. The SwissStandSim model was used to simulate the biomass growth under different harvesting and silvicultural strategies, allowing for sustainability to be assessed for each nutrient at a given intensity of use. This assessment was made per rotation period based on two criteria: (i) nutrient supply and (ii) total stocking volume. As a result, it can be noted that the accurate estimation of individual fluxes is essential for assessing the sustainability of forestry practices and that it needs detailed site-specific data. Various influencing factors turned out to be important, particularly the assumed depth of the root zone. [ABSTRACT FROM AUTHOR]

The Palaeo- to Neoarchaean Bundelkhand Craton (BkC) in central India has received attention due to its felsic crust evolution. There are two linear patches of relict greenstone belts in the BkC, and the central greenstone belt has been the focus of extensive research for the past two decades. In contrast, the southern greenstone belt has received inadequate attention. At the southern BkC, the E-W Madawara Greenstone Belt is represented by patches of remnant mantle serpentinites and metasedimentary rocks that are tectonically juxtaposed with Archaean basement TTG gneisses and Proterozoic Bijawar Group of rocks. This study highlights key findings from fields, geological maps, petrography, and a large number of whole rock chemical analyses of serpentinites and spinel chemistry to unravel the tectonic evolution story. We identified two serpentinites with contrasting petrological and geochemical properties: spinel peridotite (SP) and talc-tremolite schist (TTS). SP is primarily dunite to harzburgite with relatively high MgO (33 wt%), enriched Yb, and shows strong re-fertilization. TTS, on the other hand, is lherzolitic and less refractory (MgO = 25 wt%). Chemically, these two serpentinites were mantle wedge and subducted peridotites, respectively. The unaltered cores of the chromium spinels represent a fore-arc setting. These findings, in conjunction with prior research, paint a compelling picture of a Neoarchaean (~2.5 Ga) subduction system once present in the southern Bundelkhand Craton. The serpentinites represent relict ophiolites – from a northerly dipping trench. It also explains a Mesoarchaean rift basin system between the two cratonic nuclei of southern Bundelkhand, which amalgamated during the Kenorland Supercontinent formation. [ABSTRACT FROM AUTHOR]