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On July 18, 2023, on the K54 + 670 ~ K54 + 700 section of G351 National Highway in Baoxing County, Ya'an City, Sichuan Province, the rock mass (30° 25′ 4.8″ N, 102° 50′ 21.84″ E) located at the entrance of Leying in the Guanyinyan Open-cut Tunnel and affected by Lushan earthquakes and heavy rainfall factors suffered a rock mass collapse accident (hereinafter referred to as the Guanyinyan collapse, or collapse). It is a typical delayed rock mass collapse event that occurs under the influences of historical earthquake sequences and rainy season rainfall. The collapsed area has the maximum thickness close to 2 m, and a volume of about 1500–2000 m3. Some collapsed rocks have rolled into the interior of the tunnel and the riverbed, and boulders with a diameter of nearly 5 m have been found in the river channel. Most of the collapsed material accumulates on the road, approximately 1260 m3, burying some 30 m of the highway, severely affecting the normal use thereof. This article used a detailed field investigation, unmanned aerial vehicle (UAV) photogrammetry, historical image comparison, and numerical simulation methods to gain a deeper understanding of the engineering geology and historical earthquake situation in the study area. A three-dimensional site model was also established to identify the rock mass structural joints and accumulation conditions in the collapsed area, and the deterioration and fracture factors and historical evolution process of the dangerous rock mass were briefly analyzed, Finally, a comparative analysis was conducted between the simulated results using the three-dimensional finite discrete element method (FDEM) and the dynamic process as evinced by of real-time video footage. The collapse mainly experienced a local instability stage, stress adjustment stage, and overall collapse-accumulation stage. The further understanding of its motion characteristics and energy evolution can provide a basis for subsequent protection design and also a valuable experience for similar research in the region. [ABSTRACT FROM AUTHOR]

Chess engines are suites of algorithms that evaluate game positions through prediction—they calculate billions of possible moves, dozens of steps into the future state of play. And over the past two decades, these algorithms have usurped humans as the principal arbiters of chess knowledge. Openings, tactics, and strategies are now all authenticated, and often dictated, by engine analysis, leading to new styles of play. This article uses the example of predictive chess engines to conceptualize an emergent temporal interplay between the future and the present. Drawing inspiration from historical metaphors of geology, this article proposes a topographical approach to temporal becoming. In this approach, engine predictions facilitate not preparations for some forecasted future state, but future‐reliant calibrations of present activity, where second‐by‐second algorithmic futures are used to make second‐by‐second decisions. [ABSTRACT FROM AUTHOR]

On the occasion of the 80th commemoration of Professor Ion Popescu-Voiteşti's demise, we can say with certainty that he still remains one of the pillars of the geological sciences in Romania. As one of the pioneers of this science in Romania, his numerous written contributions also include a significant number of illustrations. Among the latter there are more than a thousand published geological sections and logs, countless hand sketches that have likeley been irretrievably lost, in addition to a remarkable collection of geology-themed maps, the majority of which are still accurate today. Herein, 13 maps signed by him are discussed, maps that are based on the studies carried out by the geologist throughout his lifetime. This work was put together not only to commemorate the aforementioned eight- decade pole, but also as an homage to the excellence that this skillful cartographer bestowed towards the Romanian scientific research. [ABSTRACT FROM AUTHOR]

Simple Summary: The riverine ecosystem of the Aurès Mountains in Algeria is situated in the southern part of the Mediterranean basin. This unique region is an important centre of speciation, with a distinct number of regional endemics—some of which are still undescribed or very poorly studied. Given the importance of biomonitoring the ecological status of surface waters in this region, as well as the need to study and protect the diversity of aquatic fauna, information on the taxonomic composition and status of regional species is essential. Our attention was focused on the mayflies of the genus Baetis Leach, 1815 (Ephemeroptera: Baetidae), a typical element of the river macrozoobenthos within the Aurès Mountains. A new species of Baetis (Baetis) dihyae sp. nov. is described for larvae and attributed to the Baetis alpinus species group using morphological and molecular evidence. The affinities of Baetis (Baetis) dihyae sp. nov. to the closely related Palearctic species Baetis (B.) alpinus (Pictet, 1843); the western Alps endemic Baetis (B.) nubecularis Eaton, 1898; and B. (B.) pasquetorum Righetti & Thomas, 2002 (reported only from a few localities in southern France) are discussed in detail. The record and further description of a new species is the first contribution to the knowledge of the relatively diverse mayfly family Baetidae, distributed in the Aurès Mountains. Establishing a representative level of diversity of the macroinvertebrate fauna of the region is closely linked to both field studies and analyses of the main pathways of invasion of its individual elements. Using an extensive data set on the geology and historical biogeography of different faunal groups as well as analysing the diversity of the Baetis alpinus species-group representatives in Western Europe and the Maghreb, we examined in this contribution its colonisation pathways in North Africa. A new species, Baetis (Baetis) dihyaesp. nov., belonging to the Baetis alpinus species group, is described and illustrated based on larval material collected in the Aurès Mountains (northeastern Algeria) in 2020–2021. This new species is closely related to three European species, e.g., Baetis (B.) alpinus (Pictet, 1843); B. (B.) nubecularis Eaton, 1898; and B. (B.) pasquetorum Righetti & Thomas, 2002 by the combination of the following characteristics: (i) more than one short, stout bristle at the tip of segment II of the maxillary palp and (ii) a well-developed paracercus. However, the new species clearly differs from all congeners of the Baetis alpinus species group primarily by the (a) structure of mouthparts—with 14–18 long submarginal setae arranged in a single irregular row on the dorsal surface of the labrum; 2–6 short, stout bristles at the tip of segment II of the maxillary palp; and segment II of the labial palp without a considerably developed apico-internal lobe); (b) setation of abdominal terga, with a few triangular-shaped scales sparsely scattered near the posterior margin only; and (c) a well-developed paracercus, comprised of more than 50 segments. Primary data on the biology and distribution of this new species are provided, and molecular affinities are verified by the analysis of COI (barcode) sequences. Detailed notes on the distribution of mayfly species belonging to the Baetis alpinus species group common in Western Europe and the western part of North Africa are presented. The historical movement of Baetis representatives between Europe, North West Africa, and subsequently Algeria, with the land bridges 'Strait of Gibraltar' and 'Strait of Sicily' as colonization routes, is discussed in detail and identified in the present study as the Western Algeria colonization path and Eastern Algeria colonization path, respectively. [ABSTRACT FROM AUTHOR]

Lembang groundwater basin has an area of 209 km2. Increased tourism activities in the Lembang Groundwater Basin require sufficient groundwater resources to support the sustainability of these tourism activities. The purpose of this study was to analyze the hydrostratigraphy of the groundwater recharge zone of the Lembang groundwater basin in the Cikole-Lembang. Electrical Resistivity Tomography (ERT) with dipole–dipole electrode array and seismic refraction was used to analyze the hydrostratigraphy. The results of ERT and seismic refraction inversion show that Tangkubanparahu Pyroclastic Fall 2 can be characterized as aquifers. This layer consists of low (123–292 Ω m) and intermediate (293–700 Ω m) resistivity value and also has low (300–1350 m/s) to medium (2700–1350 m/s) velocity. Tangkubanparahu lava (Tl) layer has a high resistivity value (701–3875 Ω m) and high (1350–2999 m/s) velocity. The Tangkubanparahu Pyroclastic Fall 1 has a resistivity of 300–700 ohms. Tangkubanparahu (Tl) lava deposits can be characterized as fracture aquifer and impermeable layers in the Tangkubanparahu volcanic hydrogeological system depend on the historical structural geology event. [ABSTRACT FROM AUTHOR]

Geoheritage represents typical geological phenomena formed through internal and external geological processes during the Earth's long evolution. It serves as a carrier of crucial information regarding the Earth's evolution, the origin of life, and changes in the geographic environment. Additionally, it is a valuable geological resource for human utilization. In order to provide essential information for the scientific protection and utilization of geoheritage resources, this paper summarizes and further categorizes the types, grades, and distribution characteristics of geoheritage in China based on extensive firsthand data obtained from recent investigations. The results can be summaried in four aspects: (1) As of the end of 2018, a total of 7,267 important geoheritage sites (including global, national, and provincial levels) have been discovered and surveyed in China. Among them, there are 3,154 geoheritage sites of basic geology, 3,935 geoheritage sites of geomorphic landscape, and 178 geoheritage sites of geological disaster. They can be further categorized into 13 classes and 46 sub-classes, such as stratigraphic sections, rock profiles, rock and soil landforms, and earthquake relics. (2) Through expert evaluations and comparative studies, there are 218 Grade I (global level) geoheritage sites, 1,919 Grade II (national level) geoheritage sites, 4,732 Grade III (provincial level) geoheritage sites, and 398 Grade IV (below provincial level) geoheritage sites in China. (3) Geoheritage in China are mainly distributed in five regions: Southwest China, East China, Central China, Northwest, and North China. The geoheritage sites of basic geology are mainly distributed in the Southwest China, Central China, East China, Northwest China, and North China, with the Southwest China having the highest number, accounting for approximately 27%. The geoheritage sites of geomorphic landscape are mainly distributed in the Southwest China, Northwest China, East China, Central China, and North China, with the Southwest China having the highest number, accounting for approximately 29%. The geoheritage sites of geological disaster are mainly distributed in the Southwest China, Northwest China, and Central China, with the Southwest China having the highest number, accounting for approximately 47%. [ABSTRACT FROM AUTHOR]

1. Introduction Aida Sergeevna Andreeva-Grigorovich, an eminent Soviet and Ukrainian palynologist and micropalaeontologist, passed away on the 13 SP th sp of April 2022 at the age of 86. Later, an updated Palaeogene dinoflagellate cyst zonation was proposed by Aida Sergeevna and her colleagues for the southern regions of the former USSR (Andreeva-Grigorovich [6]) and Ukraine (Andrejeva-Grigorovich and Shevchenko [26]; Andreeva-Grigorovich et al. [23]). For example, she established a new genus ( I Carpatella i ), and described 18 new species (Grigorovich [33], [34]; Andreeva-Grigorovich and Savitskaya [18], [19]; Andreeva-Grigorovich et al. [23]). Aida Sergeevna paid special attention to the study of boundary strata such as the Eocene/Oligocene transition (Andreeva-Grigorovich and Portnyagina [17]; Andreeva-Grigorovich [5]; Andreeva-Grigorovich et al. [22], [13]) and the Palaeogene/Neogene boundary (Grigorovich [36]; Andreeva-Grigorovich and Gruzman [10], [11]; Andreeva-Grigorovich [7]). [Extracted from the article]

For more than half a century, nuclear energy has been among the main issues of public concern, and thus of political, social as well as environmental debate. Nuclear energy has generated a long-standing controversy that began with the atomic bombs on Hiroshima and Nagasaki which comprise one of the most crucial turning points of contemporary history, from WWII up to the present. This paper aims to deal with a shorter period within this long and still controversial history. It focuses on the 1970s, when in Italy—as well as in the United States and Western Europe—the 1973 oil crisis made clear the need to diversify energy supply sources. As a result, national and international interest in nuclear power increased. The transition to a fully-fledged nuclear industry was to be achieved by the end of the century, with the launch of the first fast breeder reactors (FBRs). In Italy, the National Committee for Nuclear Energy (Comitato Nazionale per l'Energia Nucleare - CNEN), in agreement with the National Electricity Board (Ente Nazionale per l'Energia Elettrica - ENEL) and the newly established regional political bodies (Regional Councils), were entrusted with the task of drawing up the national map of sites suitable for nuclear facilities, and especially for nuclear power plants. The paper aims to provide an overview of the main geological issues that fueled the Italian 'nuclear siting controversy' during the 1970s. It focuses also on some still unpublished topics, such as those about the ENEL–CNEN Joint Study Commission for the Seismic Problems Associated with the Installation of Nuclear Plants and the drafting of a first national map of areas suitable for radioactive waste repositories. The matters under discussion here are significant because of the link with some key issues still open in contemporary debates on nuclear energy, such as planning and siting of nuclear facilities. It is also worth noting that some current global emergencies (e.g., the war in Ukraine and climate change) have brought the European, and more generally international, debate back to the urgency of energy diversification, including nuclear power in the energy generation mix. Historical analysis, although focused on particular case studies from the past, can help to better understand such a complex issue. [ABSTRACT FROM AUTHOR]

To study the carbon burial rates in different sedimentary environments in Lianyungang coastal area since the Late Pleistocene, two deep boreholes of ZK1 and ZK2 were deployed to carry out measurements of sediment TOC (total organic carbon) and TN (total nitrogen) content, as well as AMS14C dating, and photoluminescence dating, soluble salts, foraminifera and particle size data, to analyse the spatial and temporal distribution characteristics of carbon burial, the sources of organic carbon and the main influential factors on carbon burial. The stratigraphic age was dated based on historical geology and sedimentary geology combined with dating data, and seven sedimentary units are classified: from bottom to top, tidal flat to nearshore coastal environment (U1, Qp31), river environment (U2, Qp32−1), river environment (U3, Qp32−2), river environment (U4, Qp32−3), coastal-shallow shelf environment (U6-1, Qh), coastal environment (U6-2, Qh), and coastal-tidal flat environment (U7, Qh). U1, U6, and U7 sedimentary units are good carbon sinks body. The average TOCBF (organic carbon burial rate) of the cohesive soil is 12.03–13.57 g m−2 a−1 for U1 cohesive soil, and the average TOCBF of the sandy soil is 2.72–7.85 g m−2 a−1. The average TOCBF of soft soil is 48.22–58.23 g m−2 a−1 for U6-2 soft soil. The average TOCBF of soft soil is 68.58–107.6 g m−2 a−1 for U7 soft soil. U2, U3 and U4 sedimentary units have low carbon sink capacity. The colour of the sediments of these three sedimentary units is mainly yellow, indicating an oxidative environment. It is assumed that most of the organic matter in the sediment was mineralised and decomposed shortly after deposition and that the amount of organic matter that could be preserved in the soil was less. The average TOCBF is between 0.68 and 2.01 g m−2 a−1. The TOCBF is mainly controlled by the sedimentation rate. The surface layer (0–20 cm) has high TOC, which is mainly due to the short burial time, during which some of the TOC has not been fully mineralised and decomposed, and the influence of human activities. The C/N (TOC/TN) is recommended for U6 sediments to analyse the source of organic matter, with C/N ranging from 5.32 to 7.42, presumably the source of sediment organic matter is mainly of marine origin. The C/N analysis of organic carbon sources is not recommended for terrestrial sediments. The conceptual model of TOC cycle in riverine and offshore sediments is summarised and refined. [ABSTRACT FROM AUTHOR]

Fault traces and offsets, cross-section length changes, paleomagnetic inclination and declination anomalies, and stress-direction indicators with ages back to 90 Ma are collected from the geologic literature on the western United States and northern Mexico. Finite-element program Restore simulates paleokinematics by weighted least squares and integrates displacements, strains, and rotations back in time, producing paleogeologic maps, as well as maps of velocity, heave rate, strain rate, and stress direction at 6 m.y. intervals. After calibrating three program parameters against neotectonic velocities from geodesy, all classes of data except inclination anomalies are fit reasonably well. The kink in the San Andreas fault near San Gorgonio Pass has been gradually restored by slip on adjacent faults and automated smoothing. Piercing- point pairs successfully restored along the San Andreas--Gulf of California plate boundary include the Pelona and Orocopia Schists at 6 Ma, the Pinnacles and Neenach Volcanics at 21 Ma, and the Jolla Vieja and Poway conglomerates adjacent to their Sonoran source at 48-42 Ma. During 18-6 Ma, rapid extension on the Oceanside detachment fault system was restored, placing present San Nicolas Island adjacent to present Rosarito, Baja California, at 18 Ma. Since ca. 18 Ma, the western Transverse Ranges have rotated 70° clockwise, restoration of which implies that sinistral faults in this province originated with NNE trends. The first contact between the Pacific and North America plates at ca. 28 Ma was not associated with any dramatic increase in dextral faulting on land; instead, the primary result was extension in the Plush Ranch--Vasquez-Diligencia basins and Colorado River corridor, probably driven by an unstable triple- junction and accelerated by heating and uplift of North America above enlarging slab windows. [ABSTRACT FROM AUTHOR]

The use of geological interpretations to better understand features that are observed outside the Earth defines what is known as planetary geology. It is a highly multi‐disciplinary field, using concepts from many areas of human knowledge to better understand the many objects of the Universe. Interpretations tend to be based on analogue models, created from observations made on the Earth and extrapolated to the many geological contexts of other celestial bodies. It is assumed that these models can always be used, as long as corrections considering differences in properties such as temperature, mass, atmospheric, crustal and mantel composition, amongst others, are made. In most cases, such correlations are possible, requiring minor to no significant modifications. However, a reasonable number of extra‐terrestrial features cannot be explained using the Earth as the unique comparison ground, requiring the use of other analogues as a basis, or even the creation of models and theories from scratch. Here, we present an overview of planetary geology: what it is, the limits of its application, the current state of the art and the meaning of this line of research in the era in which we live, where the exploration of other objects of the Solar System is a reality. [ABSTRACT FROM AUTHOR]

Since the major flood event in 2007, RPS has been deeply involved in investigating, understanding and reducing flood risk across the Hull and Haltemprice catchment. RPS has developed and refined a complex integrated catchment model by combining Yorkshire Water's model of below-ground assets with data for the watercourses and overland flow paths obtained from the Environment Agency, East Riding of Yorkshire Council and Hull City Council. RPS used the model to identify major schemes, leading to the design of flood alleviation schemes at Willerby and Derringham, Anlaby and East Ella, and Cottingham and Orchard Park. With further enhancements, the model has been used to better understanding of the complex interactions between the various water systems and solutions are being identified for a long-term plan. Hull has many unique features, driven by its topography, geology and the historical developments of its sewerage network and waterways. These specific challenges require bespoke solutions and there is a clear desire among the partner organisations to work together to drive contemporary blue–green solutions. This requires multi-agency working and progressive thinking to deliver effective flood risk management. This paper reviews the challenges in understanding and resolving these issues. [ABSTRACT FROM AUTHOR]

The in situ discovery of the first Peking Man skull in December 1929 was a dramatic historical event in geology and paleoanthropology. Two iconic photographs appear widely in books on Peking Man (formerly Sinanthropus pekinensis), and they show a group of Chinese and Western geologists inside a caravansary at Zhoukoudian (Choukoutien) near Beijing. Long-standing issues of inconsistencies, uncertainties and lack of context regarding these photographs are addressed by using clues from published works as well as from photographs in the collection of China's first vertebrate paleontologist Dr. Yang Zhongjian (1897–1979; C. C. Young). The paper determines the year of the photographs, their connection to other photographs, the identity of a tall man in one of the photographs, and the exact date and occasion of the event. Chinese-Western interaction of the Zhoukoudian team is discussed, and unpublished letters between Yang and Western scientists including Davidson Black (1884–1934) are presented to give a personal touch to the historical context surrounding the Peking Man discovery. [ABSTRACT FROM AUTHOR]

A large part of the hydrated oceanic lithosphere consists of serpentinites exposed in ophiolites. Serpentinites constitute reactive chemical and thermal systems and potentially represent an effective sink for CO2. Understanding carbonation mechanisms within ophiolites are almost exclusively based on studies of outcrops, which can limit the interpretation of fossil hydrothermal systems. We present stable and radiogenic carbon isotope data that provide insights into the isotopic trends and fluid evolution of peridotite carbonation in ICDP Oman Drilling Project drill holes BA1B (400‐m deep) and BA3A (300‐m deep). Geochemical investigations of the carbonates in serpentinites indicate formation in the last 50 kyr, implying a distinctly different phase of alteration than the initial oceanic hydration and serpentinization of the Samail Ophiolite. The oldest carbonates (∼31 to >50 kyr) are localized calcite, dolomite, and aragonite veins, formed between 26°C and 43°C and related to focused fluid flow. Subsequent pervasive small amounts of dispersed carbonate precipitated in the last 1,000 years. Macroscopic brecciation and veining of the peridotite indicate that carbonation is influenced by tectonic features allowing infiltration of fluids over extended periods and at different structural levels such as along fracture planes and micro‐fractures and grain boundaries, causing large‐scale hydration of the ophiolite. The formation of dispersed carbonate is related to percolating fluids with δ18O lower than modern ground and meteoric water. Our study shows that radiocarbon investigations are an essential tool to interpret the carbonation history and that stable oxygen and carbon isotopes alone can result in ambiguous interpretations. Plain Language Summary: Water‐rock interactions that have biological and economic importance have received increasing interest in recent years. Carbon species, stored in the atmosphere, biosphere, oceans, and lithosphere, are profoundly affected by biotically and abiotically controlled exchange reactions among these reservoirs. Carbon is an essential element for life and contributes to the greenhouse effect in the form of CO2 and CH4. Unraveling water‐rock reactions that transform atmospheric CO2 into thermodynamically stable carbonates helps to better understand long‐term carbon storage in the lithosphere and its long‐term influence on climate and to better evaluate the potential for life within the lithosphere. This study uses samples recovered by drilling mantle sequences of the Wadi Tayin Massif in Oman and presents chemical data to evaluate carbon sources, speciation, and transformations. The Wadi Tayin Massif is located in the Samail Ophiolite and comprises mantle rocks. Mantle rocks react in contact with water to form serpentine and create an environment that promotes the transformation of CO2 into carbonates. Our results demonstrate large‐scale carbonization of the massif and a dominance of dispersed carbonate formation below the surface. Our study provides insights into the carbon cycle and will help to evaluate the potential of mantle rocks to store carbon and sustain life. Key Points: Two carbonate occurrences are observed: localized dolomite, calcite, and aragonite veins and pervasive dispersed carbonatesCarbonate precipitation in the peridotite occurred in the last 50 kyr at moderate temperatures, post‐dating ocean‐floor serpentinizationThe oxygen isotope composition of dispersed carbonates indicates precipitation from highly 18O‐depleted fossil groundwater [ABSTRACT FROM AUTHOR]

Carbon isotope records from alkenone biomarkers (εp37:2) produced by haptophyte algae are frequently used for atmospheric CO2 paleobarometry, but this method has yielded inconsistent results during periods where CO2 variations are known independently. Recent syntheses of algal cultures have quantitatively demonstrated that εp37:2 indeed records CO2 information: εp37:2 increases as aqueous CO2 concentrations increase relative to carbon demand. However, interpretations of εp37:2 are complicated by irradiance, where higher irradiance yields higher εp37:2. Here we examine the roles of physiology and environment in setting εp37:2 in the ocean. We compile water‐column and sediment core‐top εp37:2 data and add new core‐top measurements, including estimates of cell sizes and growth rates of the alkenone‐producing population. In support of culture studies, we find irradiance to be a key control on εp37:2 in the modern ocean. We test a culture‐derived model of εp37:2 and find that the quantitative relationships calibrated in culture experiments can be used to predict εp37:2 in sediment samples. In water‐column samples, the model substantially overestimates εp37:2, largely resulting from higher irradiance at the depth of sample collection than the integrated light conditions under which the sampled biomass was produced and vertically mixed to the collection depth. We argue that the theory underpinning the conventional diffusive alkenone carbon isotope fractionation model, including the "b" parameter, is not supported by field data and should not be used to reconstruct past CO2 changes. Future estimates of CO2 from εp37:2 should use empirical or mechanistic models to quantitatively account for irradiance and cell size variations. Key Points: Irradiance is a primary control on alkenone carbon isotope fractionation in the natural environmentCulture‐calibrated model can predict alkenone carbon isotope fractionation in core‐top sediment samplesDiffusive model "b" value is not correlated with growth rate: diffusive model should not be used for paleobarometry [ABSTRACT FROM AUTHOR]

Inquiry-based learning is an educational strategy that emphasizes the student's role in the learning process by having them propose and test hypotheses through experimentation and/or the collection of observational data. It emphasizes active participation, allowing students to take ownership of their learning. In doing so, inquiry-based learning results in the building of the critical thinking and communication skills necessary for participation in all fields of study. In this study, we provide an example of how to adapt an inquiry-based activity used in upper-level paleontology courses so that it can be used in all paleontology-related courses, as well as in lower-level historical geology courses. In paleoecology, large surfaces of substrate with encrusting organisms provide a wealth of paleoecologic information about the ancient communities and are an excellent tool for inquiry-based learning. However, a challenge in paleoecology is that large slabs of rock containing fossil communities are not easy to obtain. In this exercise, students create a simulated substrate using paper and stickers. Feedback showed that students were engaged in the process of doing science and used the skills that they had learned throughout the semester. They gained self-confidence and realized that they can, in fact, do science. [ABSTRACT FROM AUTHOR]

The complex urban geology of the historic center of Naples is characterized by the emplacement of products from two adjoining volcanic areas that were reworked by alluvial and coastal processes. To expand the geologic knowledge of this densely populated area, multidisciplinary research was carried out on the recently drilled San Marcellino borehole, as part of a larger borehole collection project. Critical revision of 290 previously drilled sequences, and a complete set of tephrostratigraphic, sedimentologic, and paleoecologic data obtained on the San Marcellino stratigraphy, informed a hydrogeological conceptual model of water circulation and paleoenvironmental reconstruction of the city historic center. Both before and after the Neapolitan Yellow Tuff eruption, ca. 15 ka, the landscape was characterized by a marine to transitional paleoenvironment. This signifies a good balance between sea-level rise and volcaniclastic inputs, consisting of both primary and remobilized deposits in an area that is also subject to bradyseismic oscillations. Amongst the primary pyroclastic deposits, the products of an explosive event from Campi Flegrei about 16 ka, with an eastward-directed sustained-column phase, were recognized. Collectively, the multidisciplinary data obtained in this study favor the presence of a double-aquifer conceptual model, characterized by a volcanic and a marine-sedimentary aquifer. [ABSTRACT FROM AUTHOR]

Dehydration and hypersalinity challenge non-marine organisms crossing the ocean. The rate of water loss and saltwater tolerance thus determine the ability to disperse over sea and further influence species distribution. Surprisingly, this association between physiology and ecology is rarely investigated in terrestrial vertebrates. Here we conducted immersion experiments to individuals and eggs of six lizard species differently distributed across Taiwan and the adjacent islands to understand if the physiological responses reflect the geographical distribution. We found that Plestiodon elegans had the highest rate of water loss and the lowest saltwater tolerance, whereas Eutropis longicaudata and E. multifasciata showed the lowest rate of water loss and the highest saltwater tolerance. Diploderma swinhonis, Hemidactylus frenatus, and Anolis sagrei had medium measurements. For the eggs, only the rigid-shelled eggs of H. frenatus were incubated successfully after treatments. While, the parchment-shelled eggs of E. longicaudata and D. swinhonis lost or gained water dramatically in the immersions without any successful incubation. Combined with the historical geology of the islands and the origin areas of each species, the inferences of the results largely explain the current distribution of these lizards across Taiwan and the adjacent islands, pioneerly showing the association between physiological capability and species distribution. [ABSTRACT FROM AUTHOR]

The Paleozoic evolution of Patagonia was the focus of controversies between its allochthonous or autochthonous origin. The arrival of plate tectonics supported new allochthonous alternatives and from an initial fixist resistance, different mobilistic hypotheses have made their way. There is currently some consensus about its allochthony, but there is no agreement on collision times or in the configuration of the continental blocks involved. Based on the present data an alternative is developed that fits better with existing information. The northeast-vergent deformation in Ventania System, the Hespérides Basin, its wide longitudinal and transverse distribution, show that collision occurred in the northern sector of Northern Patagonian Massif, and extended through the southern African Gondwanides. Their similar metamorphic and tectonic patterns identified a previous southward subduction with a Permian climax, characteristic of a continent-continent collision. The associated magmatic arc has been partially obliterated by slab-breakoff and delamination in the Late Permian-Triassic. The western magmatic belt along the Pacific margin is older, spanning from Devonian to mid-Carboniferous. The Chaitenia island arc collision in Upper Devonian produced an episode of exhumation and uplift. This western belt extends into Tierra del Fuego island and its contour allows tentatively to recognize a Southern Patagonian terrane. It is speculated that this block may have included the Antarctic Peninsula, although more data is needed to characterize its composition and areal development. However, it is concluded that the dimensions of this southern terrane cannot justify the broad regional deformation of the Gondwanides. [ABSTRACT FROM AUTHOR]

In this unit students evaluate evidence quality, learn central organizing principles of geology, and develop a more sophisticated understanding of the nature of science in the context of a model-based inquiry unit. In this unit students learn about three models describing how the Earth's surface might experience large-scale changes over long periods of time: The shrinking Earth model Continental drift Plate tectonics These three geologic models have been accepted by different factions of the scientific community at different times (Oreskes 1988). This is just a sample of the many geologists and earth scientists whose work has contributed to science; teachers are encouraged to adapt this as they see fit and have students explore the lives of other scientists as well. Concluding thoughts: deepening students' understanding of the nature of science The goals of this unit are to help students learn central organizing principles of geology, and also to develop a more sophisticated sense of the nature of science. [Extracted from the article]

This review aims to synthesize the current knowledge of sediment dynamics using insights from long‐term research conducted in the watershed draining to the Chesapeake Bay, the largest estuary in the U.S., to inform management actions to restore the estuary and its watershed. The sediment dynamics of the Chesapeake are typical of many impaired watersheds and estuaries around the world, and this synthesis is intended to be relevant and transferable to other sediment‐impaired systems. The watershed's sediment sources, transport, delivery, and impacts are discussed with implications for effectively implementing best management practices (BMPs) to mitigate sediment issues. This synthesis revealed three key issues to consider when planning actions to reduce sediment loading: Scale, time, and land use. Geology and historical land use generated a template that current land use and climate, in addition to management, are acting upon to control sediment delivery. Important sediment sources in the Chesapeake include the Piedmont physiographic region, urban, and agricultural land use, and streambank erosion of headwater streams, whereas floodplain trapping is important along larger streams and rivers. Implementation of BMPs is widespread and is predicted to lead to decreased sediment loading; however, reworking of legacy sediment stored in stream valleys, with potentially long residence times in storage, can delay and complicate detection of the effects of BMPs on sediment loads. In conclusion, the improved understanding of sediment sources, storage areas, and transport lag times reviewed here can help target choices of BMP types and locations to better manage sediment problems—for both local streams and receiving waters. This article is categorized under:Science of Water > Water QualityWater and Life > Stresses and Pressures on EcosystemsWater and Life > Conservation, Management, and Awareness [ABSTRACT FROM AUTHOR]

The use of Right dihedral method, Lisle graph, and Mohr diagram allows the analysis of the paleostress. Fault slip data were measured for eighteen data of two stations located within Chia Gara structure in Dohuk area in the High Folded Zone, Northern Iraq. Depending on Mohr diagram, Bott equation, and vertical thickness, the magnitudes of the paleostress at the time of the tectonic activity were determined. Firstly, Georient Software was used to estimate the orientation of the paleostresses (σ1, σ2 and σ3). Secondly, using the rupture -friction law, taking into account the depth of the overburden, the vertical stress (σv) was calculated to determine the magnitude of the paleostresses in the study area. The values in station one (hinge area, eight data) were σ1=7100, σ2=4121.5, and σ3=1143 bars, whereas the values in station two (the north limb of structure, ten data) were σ1=3740, σ2=1585, and σ3=570 bars. The high magnitudes of the principal stress axes may refer to the active tectonic events which led to the deformation of the area during the Mesozoic Era and the Tertiary period. The study area shows the existence of two types of the faults, the first type is the reactivated faults, the poles of which lie between the sliding line and Mohr envelope. The second type is the inactive faults, with poles lying on the great circle of Mohr diagram. [ABSTRACT FROM AUTHOR]

Historical geology, climatic oscillations, and seed dispersal capabilities are thought to influence the population dynamics and genetics of plants, especially for distribution-restricted and threatened species. Investigating the genetic resources within and among taxa is a prerequisite for conservation management. The Cycas taiwaniana complex consists of six endangered species that are endemic to South China. In this study, we investigated the relationship between phylogeographic history and the genetic structure of the C. taiwaniana complex. To estimate the phylogeographic history of the complex, we assessed the genetic structure and divergence time, and performed phylogenetic and demographic historical analyses. Two chloroplast DNA intergenic regions (cpDNA), two single-copy nuclear genes (SCNGs), and six microsatellite loci (SSR) were sequenced for 18 populations. The SCNG data indicated a high genetic diversity within populations, a low genetic diversity among populations, and significant genetic differentiation among populations. Significant phylogeographical structure was detected. Structure and phylogenetic analyses both revealed that the 18 populations of the C. taiwaniana complex have two main lineages, which were estimated to diverge in the Middle Pleistocene. We propose that Cycas fairylakea was incorporated into Cycas szechuanensis and that the other populations, which are mainly located on Hainan Island, merged into one lineage. Bayesian skyline plot analyses revealed that the C. taiwaniana complex experienced a recent decline, suggesting that the complex probably experienced a bottleneck event. We infer that the genetic structure of the C. taiwaniana complex has been affected by Pleistocene climate shifts, sea-level oscillations, and human activities. In addition to providing new insights into the evolutionary legacy of the genus, the genetic characterizations will be useful for the conservation of Cycas species. [ABSTRACT FROM AUTHOR]

The Chilean territory is rich in evidence of the geological history of the Earth, presenting as the clearest evidence of this presence of the Andean Cordillera along its entire north-south extension. These conditions are not always understood by the country, relegating the geological wealth of the territory to a landscape backdrop condition, but without understanding the interdependence between geology and geomorphology and the historical, economic and cultural development of human societies. The creation of the UNESCO Global Network of Geoparks and the interest in developing one of these Geoparks in the commune of San Jose de Maipo presents a great opportunity to facilitate the interpretation processes that characterize ecotourism, while approaching this situation to the main domestic tourism issuing market and favor local development. This work explores both the fundamental concepts associated with the existence of Geotourism and Geoparks, as well as the conditions and opportunities presented to the community of San Jose de Maipo of reaching the creation of a Geopark in in the Cajon del Maipo area. [ABSTRACT FROM AUTHOR]

This paper sets the historical context for the Journal of Structural Geology when it was first published in 1979. The major advances in Structural Geology over the past 40 years are then highlighted. Finally, ten Grand Challenges for the next decade are nominated. • The history of Structural Geology up until the first issue of the Journal of Structural Geology in 1979 is highlighted. • Progress from 1979 to the present is summarised. • Some Grand Challenges for the future are outlined. [ABSTRACT FROM AUTHOR]

The evolution of geology as an independent science can be envisaged as a relatively continuous process yet marked by three fundamental steps. These represented singularities which established significant advances in the epistemological and heuristic power of the discipline. This interpretation of history has to be strictly based on an evaluation of the epistemological basis of geology according to modern scholarship. The recognition of these 'golden spikes', albeit artificial, may help geologists to better grasp the philosophical position of geology with respect to other sciences. The first step was the publication of Steno's Prodromus in 1669, which established the methodological rules for decoding a geologic history from the geometrical arrangements of beds. The second step was the founding of the Geological Society of London in 1807, an act by which a new community recognized itself as a scientific and professional entity applying a novel methodology in the study of Earth. Their approach represented a synthesis of the Wernerian-historical and the Huttonian-causal methods. The third step was the emergence of plate tectonics in 1967, when the actualistic method (i.e. uniformity of laws and processes) could be extended to the interpretation of the whole lithosphere. At the same time, the heuristic power of historical geology was validated by independent, physico-mathematical testing. [ABSTRACT FROM AUTHOR]

Abstract We present recent study results of the Lower Triassic conodont succession from the Ganxi and Jianshi areas of Enshi city, western Hubei Province, South China, which were situated on a carbonate ramp at the northeastern margin of the Upper Yangtze Platform. Therein, the uppermost Permian to Lower Triassic succession is well exposed and yielded abundant conodonts. A total of nine conodont zones are differentiated: (1) Clarkina yini Zone, (2) Clarkina meishanensis Zone, (3) Hindeodus changxingensis Zone, (4) Hindeodus parvus Zone, (5) Hindeodus postparvus Zone, (6) Clarkina planata Zone, (7) Neoclarkina aff. discreta Zone, (8) Neospathodus dieneri Zone, and (9) Novispathodus waageni Zone. The Ns. dieneri M1, Ns. dieneri M2, and Ns. dieneri M3 Subzones have also been distinguished within the Ns. dieneri Zone, and the Nv. waageni eowaageni and Nv. waageni waageni Subzones are recognizable within the Nv. waageni Zone in Jianshi. Most of the zones occur in succession, but the C. planata Zone is a local ecozone reflecting deeper water biofacies during H. postparvus Zone time. In the Jianshi section, the Permian–Triassic boundary is placed at Bed 136-2 based on the appearance of Hindeodus parvus immediately above the disappearance of Changhsingian taxa, while the Induan–Olenekian boundary (IOB) is drawn at Bed 225 + 40 cm based on the first appearance of Nv. waageni eowaageni within the upper range of the Ns. dieneri Zone indices. The Enshi conodont zones overall correlate well with those recognized elsewhere in South China and worldwide. Highlights • Nine conodont zones were established from the Enshi area. • The Permian–Triassic boundary is placed at Bed 136-2 in the Jianshi section. • The Induan–Olenekian boundary is drawn at Bed 225 + 40 cm in the Jianshi section. • The Enshi conodont zones overall correlate well with those recognized elsewhere. [ABSTRACT FROM AUTHOR]

Abstract On Earth, chemical weathering of basaltic rocks not only modulates the climate change, but also plays a crucial role on the ocean oxygenation and ecosystem evolution. Records of paleo-weathered crusts are a challenge to identify because they are obscured by subsequent alteration processes and buried by the newly formed volcanic lavas. However, late formed volcanic rocks theoretically could record previously weathered crust via their assimilation and fractional crystallization (AFC) processes. Here, we present a systematic study on major, trace elements and Sr-Nd-Mg isotopes in a suite of Changbaishan early formed basalts and late erupted trachytes from Northeast China. Detailed evidence of field observation, geochemical signature and rhyolite-MELTS simulations suggest that trachytes mainly originated from deep fractional crystallization of basaltic melts. The low abundant trachytes from the stratigraphic layer above the basalts display decoupled Mg Sr and Nd isotopes. δ26Mg and 87Sr/86Sr in trachytes range from −0.27 up to +0.94‰ (the heaviest isotopic composition ever reported for Mg in the igneous rocks) and 0.70490 to 0.71065, respectively, which are significantly elevated relative to that of their mantle source. However, they preserved mantle source-like 143Nd/144Nd (0.512584 to 0.512656) ratios. These unusual characteristics cannot be explained by thermal diffusion, fractional crystallization or simple crustal contamination processes. Specifically, δ26Mg correlates positively with SiO 2 and 87Sr/86Sr, and negatively with MgO, CaO, Al 2 O 3 , Sr and Nb/U indicators. The highly elevated Mg and Sr isotopes but limited Nd isotopic changes in trachytes require a component to be the relatively younger weathering residue of basaltic rocks. Taking this component as a wall rock endmember, the well-developed above correlations can be best modelled by AFC processes. This reflects that some trachytes in the aftermath of AFC processes almost fully lost their primary source characteristics, but inherited the intense chemical weathering signature of basalts. This event probably occurred in the middle Miocene as studies of paleosols showed humid and warm climate during that period after the initial eruption of Changbaishan basalts. Therefore, our study as a specific case for the first time provides an efficient way to explore paleo-weathering of basaltic crusts buried in the Earth's surface, through comprehensive investigating Mg, Sr and Nd isotopes of volcanic rocks developed in the late stage of a volcano cone. [ABSTRACT FROM AUTHOR]