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The objective of this study was to analyse the characteristics of highly cited papers (HCPs) in the research field of geosciences based on the Essential Science Indicators database, which is widely used to evaluate institutions and researchers. Multi-aspects, including country/region's productivity distribution, organizations, authors, detailed categories and hot topics, journals and implications of collaboration networks have been explored in this study. The main findings are: (1) USA ranks first in geosciences research with over 60% global share, with most of the leading organizations (12 out of 15) also from that country. (2) The percentage of international collaborations is high in this research field; the collaboration shows tangled networks among countries/regions (organizations) and also indicates close connections worldwide. (3) Despite the dominance of USA in productivity, only 5 of the top 15 authors are from that country, and relatively tight collaboration networks are found among the top authors. (4) The current high-level researches in geosciences focus on meteorology, geochemistry, geophysics, remote sensing and oceanography, and topics involving climate change draw most of the attention. [ABSTRACT FROM AUTHOR]

Abstract To evaluate the effect of brown-rot fungi Oligoporus placenta and earthworm Eisenia fetida on decomposition of paper mill sludge, the paper mill sludge was mixed with cow dung in 0, 25, 50, 75, and 100% proportions and changes in physicochemical quality of waste mixtures was carried out for 28 days. All waste mixtures were treated with: Setup-I (E. fetida), Setup-II (O. placenta) and, Setup-III (E. fetida + O. placenta). A decrease in total organic carbon, C/N ratio and cellulose but an increase in total kjeldhal nitrogen, total phosphorus, total potassium and pH was recorded. The paper mill sludge in 50–75% proportion in feedstock showed the better results and rate of mineralisation were in order: Setup-III > Setup-I > Setup-II. The proportion of CD has direct role in waste mineralisation. The microbial population (bacterial, fungal and actinomycetes) and earthworm biomass were also high in Setup-III, suggesting the influence of brown-rot fungi on paper mill sludge humification. Results indicate that fungal inoculate in vermicomposting was effective in decomposing cellulose-rich industrial sludge. Graphical abstract Image 1 Highlights • The decomposition of PPMS in vermicomposting and vermibed added with brown-rot fungi is assessed. • The combination of E. fetida and O. placeta caused more humification in PPMS. • The PPMS in 50–75% proportion with CD showed higher nutrient mineralisation. • The earthworm growth and microbial population in waste mixtures also influenced by the treatment type. [ABSTRACT FROM AUTHOR]

Kaolin-group minerals occur in nature as the result of high-sulfidation acid sulfate, sulfur-poor HCl-, HF- and H2CO3-rich acidic fluid-related hydrothermal alterations and in situ geochemical weathering. These minerals possess different crystallographic and chemical properties that determine their application areas, mainly in the ceramic and paper industries, and as nanocomposite materials. The physicochemical properties of hydrothermal kaolin deposits are the result of the type of parent rock, the effect of the regional tectonism-associated magmatism, and the chemical features of hydrothermal fluids that interact with the deep basement rocks. However, understanding these geothermal systems is one of the most challenging issues due to the rich mineralogical assemblages, complex geochemistry and isotopic data of hydrothermal alteration zones. This study evaluates the formation of hydrothermal-origin kaolin-group minerals by considering their characteristics of hydrothermal alteration, isotopic compositions and differences in characteristic properties of low- and high-sulfidation occurrences; this paper also addresses mineralogical and structural differences between hypogene and supergene kaolin formations, and kaolin–alunite–pyrophyllite association, and it provides examples of worldwide occurrences. The study of the mineralogical assemblages, geochemistry and isotopic data of the hydrothermal alteration zones is one of the most challenging subjects in terms of gaining a detailed understanding of the geothermal systems. Silicification processes are subsequent to late-stage alteration after the completion of kaolinization processes, erasing existing hydrothermal mineralogical and geochemical traces and making interpretation difficult. In the early stages involving magmatic–hydrothermal-origin acidic geothermal fluids, the latter comes from the disproportionation of SO2 (+H2O) and H2S oxidation to H2SO4 in hydrothermal environments. In the later stages, due to spatial and temporal changes over time in the chemistry of geothermal fluids, the system comes to have a more alkali–chloride composition, with neutral pH waters frequently saturated with amorphous silica which characteristically precipitate as siliceous sinter deposits containing large amounts of opal-A. [ABSTRACT FROM AUTHOR]

Technological advancements have made rock engineering more data-driven, leading to increased use of machine learning (ML). While the use of ML in rock engineering has the potential to transform the industry, several methodological issues should first be addressed: (i) rock engineering's use of biased (poor quality) data, resulting in biased ML models and (ii) limited rock mass classification and characterization data. If these issues are not addressed, rock engineering risks using unreliable ML models that can have potential real-life adverse impacts. This paper aims to provide an overview of these methodological issues and demonstrate their impact on the reliability of ML models using surrogate models. To take full advantage of the benefits of ML, rock engineers should make sure that their ML models are reliable by ensuring that there are sufficient unbiased data to develop reliable ML models. In the context of this paper, the term sufficient retains a relative meaning since the amount of data that is sufficient to develop reliable a ML models depends on the problem under consideration and the application of the ML model (e.g., pre-feasibility, feasibility, design stage). [ABSTRACT FROM AUTHOR]

The First International Symposium on Marine Engineering Geology (ISMEG2016) was held in Qingdao, China, 21-24 October 2016. The symposium was sponsored by the Marine Engineering Geology Commission, International Association for Engineering Geology and Environment (IAEG-C34) and hosted by the Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering at Ocean University of China. Over 200 researchers worldwide participated in the symposium, which included 13 plenary reports, 17 keynote reports, and more than 40 oral presentations and posters. All papers appearing in this thematic issue of Bulletin of Engineering Geology and the Environment are original scientific papers that have been internationally reviewed, focusing on the marine geohazards, engineering characteristics of marine soil, coastal and ocean engineering, and wave-soil interactions encountered in the latest practice of marine engineering geology. [ABSTRACT FROM AUTHOR]

A reliable geological model plays a fundamental role in the efficiency and safety of mountain tunnel construction. However, regional models based on limited survey data represent macroscopic geological environments but not detailed internal geological characteristics, especially at tunnel portals with complex geological conditions. This paper presents a comprehensive methodological framework for refined modeling of the tunnel surrounding rock and subsequent mechanics analysis, with a particular focus on natural space distortion of hard-soft rock interfaces at tunnel portals. The progressive prediction of geological structures is developed considering multi-source data derived from the tunnel survey and excavation stages. To improve the accuracy of the models, a novel modeling method is proposed to integrate multi-source and multi-scale data based on data extraction and potential field interpolation. Finally, a regional-scale model and an engineering-scale model are built, providing a clear insight into geological phenomena and supporting numerical calculation. In addition, the proposed framework is applied to a case study, the Long-tou mountain tunnel project in Guangzhou, China, where the dominant rock type is granite. The results show that the data integration and modeling methods effectively improve model structure refinement. The improved model's calculation deviation is reduced by about 10% to 20% in the mechanical analysis. This study contributes to revealing the complex geological environment with singular interfaces and promoting the safety and performance of mountain tunneling. [ABSTRACT FROM AUTHOR]

The lateral response of combined pile-raft foundations (CPRFs) adjacent to tunnel excavation is a challenging problem owing to the complexity of the pile-raft connections. In current engineering practices, the impact of these connections on the lateral performance of CPRFs is frequently overlooked, despite their importance. To address this issue, this study conducted three-dimensional finite element analyses to evaluate the contribution of pile-raft connections to the tunnelling-induced lateral performance of CPRFs in saturated clay. In the analysis, both passive and active loading at the pile head could be considered by varying the tunnel depth. Several parameter studies, such as relative pile-raft modulus, pile embedded modulus, pile embedded depths, and pile shaft skin friction, were conducted to determine the optimal design parameters for CPRFs. The results indicate that pile-raft connections significantly affect the tunnellinginduced deflections and bending moments of pile groups. Inspired by the results, a simplified design method, the pile-raft connection coefficient Kc was proposed. Additionally, the pile-head restraint percentage was established to make a relationship with the pile-raft connection coefficient in order to assess the pile-raft connection and guide the pile-raft design. In this paper, the recommended range value of Kc is 10--200 and the range value of pile-head restraint percentage is 24%--42%. [ABSTRACT FROM AUTHOR]

A traditional block caving mine considers the development of an undercut level that allows blocky or veined rock masses to fracture, fail, and unravel when the undercut area is large enough. Once caving initiates, the rock mass progressively fails when induced stresses overcome the rock mass strength and when fractured rock masses unravel under gravity into the undercut and draw points. If the ability of a rock mass to cave is not enough, the cave will not propagate efficiently, thereby affecting fragmentation and ore recovery with the potential to upset safety and productivity if there are hang-ups in draw points. Therefore, cavability is critical for the success of a caving operation. Despite improving technological trends, most of the empirical approaches used for designing block caving mines were proposed 40 years ago, and their updates do not include most of the new understanding of mining geomechanics acquired since then. More importantly, the role of geology is often overlooked. This paper critically reviews the state of the art in orebody cavability prediction and explores whether traditional and statistical techniques can be applied for predicting cavability better. The review highlights the importance of geology that is often overlooked in orebody cavability prediction. [ABSTRACT FROM AUTHOR]

The Paleoproterozoic Belcher Group (ca. 2.0 to 1.83 Ga) occurs on the remote Belcher Islands of Hudson Bay in Nunavut, Canada. It includes nearly nine kilometres of wellpreserved siliciclastic and carbonate sedimentary rocks, deposited initially in a marginal to shallow marine setting representing one of the first true continental shelf environments on the proto-Canadian Shield. A wide variety of depositional facies exists within the Belcher Group, and it is particularly well known for its spectacular stromatolites in dolostone. In addition to these macroscopic features, two of its formations (Kasegalik and McLeary) contain intact microfossils of Eoentophysalis belcherensis, the oldest known occurrence of cyanobacteria in the geological record. The uppermost part of the Belcher Group contains sedimentary rocks of very different character that represent a younger foreland basin that developed in response to accretionary and collisional processes of the Trans-Hudson orogen. These younger formations (Omarolluk and Loaf) consist of a thick sequence of turbidites, overlain by arkose and other immature clastic sedimentary rocks. A defining characteristic of the Omarolluk Formation is the presence of calcareous concretions. The Omarolluk Formation shares attributes with "omars", which are glacially transported clasts that occur both locally and further afield throughout parts of Canada and the northern United States and have helped characterize Pleistocene ice-flow trends across the continent. The Belcher Group also includes two formations dominated by spectacular mafic volcanic rocks. The earlier episode, represented by the Eskimo Formation, reflects eruption of largely subaerial volcanic flows interpreted to represent flood basalt associated with the rifting of Archean basement during the establishment of the continental shelf. A later volcanic episode (the Flaherty Formation) is dominated by submarine pillowed basalt flows and has been assigned to varied tectonic settings, including volcanic arcs related to subduction and oceanic plateaus related to mantle plume activity and renewed rifting along the continental margin. This later volcanism marks the transition from shelf to foreland basin. Mafic sills and related intrusions (Haig intrusions) occur in the middle and lower part of the Belcher Group. Thermal and chemical interactions between mafic magma and calcareous shale generated unusual rocks that are well known in Nunavut as highquality artisanal carving stone. The Belcher Group also contains Superior-type iron formations that have attracted past exploration interest. The Belcher Group is a unique geological entity defined by its wide variety of rock types, its superb exposures, and its potential to illustrate many important geological processes in a formative time in Earth's history. It is also a unique microfossil paleontological resource, and its deposition brackets a crucial and much-debated interval of Precambrian atmospheric and oceanic evolution. It represents an important scientific resource in the context of understanding such changes. This general review paper highlights its most important features, discusses its potential for future research and contributes to wider discussions about its possible future role as a protected area within Nunavut. [ABSTRACT FROM AUTHOR]

Enrolment in geology-related courses has declined over the last few decades, in part due to a lack of understanding of the subject and its relevance to contemporary society. Although a popular medium for entertainment, video games also hold significant pedagogical potential to overcome this problem by immersing players in geology-related topics through the portrayal of a broad range of geological disciplines in the medium's dynamic environments. This paper focuses on volcanology as portrayed in Nintendo's The Legend of Zelda series' (1986-present) Death Mountain, a recurring volcanic peak in the franchise. Volcanic features in each game are documented and compared to real-world examples to determine the accuracy of how the volcanism evolves over time across instalments in the series. I argue that the volcanic history of Death Mountain provides a reasonably realistic evolution, beginning with volcanic hazards like rockfalls and lava from an active stratovolcano, and progressing over time to introduce hydrothermal systems. Then, during divergent timelines, Death Mountain's volcanism shifts to either explosive, shallow-water eruptions or to showing evidence of massive explosive activity. Through this, I argue that the popularity of The Legend of Zelda series and the gradual introduction of volcanic features can be used together to change the perception of geology as "boring" and encourage people to study the subject by offering a fun and immersive means to engage with its content. [ABSTRACT FROM AUTHOR]

Parkinson, F.; Douglas, K.; Li, Z.; Meijer, A.; Stacey, C.D.; Kung, R., and Podhorodeski, A., 2024. A generalized semiautomated method for seabed geology classification using multibeam data and maximum likelihood classification. Journal of Coastal Research, 40(1), 1–16. Charlotte (North Carolina), ISSN 0749-0208. This paper presents a GIS-based model to perform semiautomated seabed classification that can act as a first-pass, pseudoclassified surficial geological map. The user can then edit the output into a finalized map in less time than by manual classification. The model uses maximum likelihood classification with unsupervised classification through iterative self-organizing clusters. This model is fully contained within the ArcGIS software suite as a ModelBuilder workflow composed of geoprocessing tools and Python script tools. Model inputs tested include different combinations of multibeam echosounder–derived data: slope, backscatter, and terrain ruggedness. Furthermore, to test the assumption of Gaussian distribution of input data required for maximum likelihood classification, Box–Cox power transformations were applied to slope and backscatter data and were used as model inputs. To illustrate the performance of the model, two locations are highlighted as case studies: Milbanke Sound and Spiller Channel, located on the central coast of British Columbia, Canada. Association between model outputs and ground-truth classes was generally weak to moderate when measured using Cramér's V association scores. Overall, the slope and backscatter parameter model had the highest scores of association. Results from an overlay analysis comparing model outputs with user-confirmed polygons show that the slope and backscatter model performs best in regions with distinct changes in the hardness of sediments but that in fjord regions dominated geologically by steeper bathymetric change, the slope parameter model may perform better. However, all model outputs had difficulty delineating bedrock units. The model has the flexibility to identify certain seabed habitat features as well, including glass sponge reefs—biologically active bioherms that have led to marine protected area designations in other areas of British Columbia. [ABSTRACT FROM AUTHOR]

Feni is located at the southeastern end of the NW-trending Tabar–Lihir–Tanga–Feni (TLTF) volcanic island chain, in northeastern Papua New Guinea. This island chain is renowned for hosting alkaline volcanics, geothermal activity, copper–gold mineralization, and mining. There is no agreed consensus on the tectonic and petrogenetic evolution of Feni. Thus, the purpose of our paper is to present the geology of Feni within the context of the regional tectonic evolution of the TLTF chain and offer a succinct and generic geodynamic model that sets the stage for our next paper. The methodologies used in this study include a critical review of published and unpublished literature in conjunction with our geological observations on Feni. The Pliocene-to-Holocene TLTF chain is a younger arc situated within the greater Eocene-to-Oligocene Melanesian Arc bounded by New Ireland to the west, the Kilinailau Trench and Ontong Java Plateau in the east, and the New Britain Trench to the south. The geological units mapped on Feni include a large volume of basaltic lava flow and trachyandesite stocks intruding a limestone and siltstone basement. Younger units include the trachyte domes, pyroclastic flow, and ash fall deposits. The major structures on Feni are normal or extensional faults such as the Niffin Graben. Feni magmatism is attributed to the petrogenetic processes of polybaric or decompression melting and crystal fractionation of magmas previously influenced by sediment assimilation, mantle wedge metasomatism, slab tears, slab melts, and subduction. Deep lithospheric normal faults provide the fluid pathways for the Feni alkaline magmas. [ABSTRACT FROM AUTHOR]

In this paper, I will show and describe a method of integrating infrared images with a 3D model of the front of an excavation in the longwall type of workings. I will also test the created 3D model for its potential usefulness in geological prospecting, used for looking for changes in geological layout at the front of the excavation. Geological information on the amount of coal in the front is important for the economic side of the excavation. The mine does not want to take out waste rock, but mostly for the safety of operations. The longwall shearers and plows are not designed for excavation in extremely changeable conditions, so if too much shale appears, this might change the speed and economic results of excavation. In addition, if a fold appears, this can destroy the excavating complex. Currently, the geological survey requires a geologist to get to the front, often to the unsupported roof part of the wall, clean the front and sample, and measure the geology. This is dangerous for the geologist. Thus, remote, infrared measurements would improve the safety of the staff and allow the survey to be taken in more places along the longwall. In this paper, I will also propose how such a system could be implemented and what the limitations are. [ABSTRACT FROM AUTHOR]

Ships' logbooks are now an accepted part of the repertoire of data sources in climate change studies. This article examines some of the particular issues surrounding logbooks from the Arctic region in the so-called pre-instrumental period. Attention is given to the means by which narrative descriptions of wind, weather and sea ice cover can be reliably expressed in index form. Consideration is also given to the various means by which these data can be most effectively managed for scientific analysis as in most cases they were not recorded for such purposes. Many such logbooks remain yet to be digitized and the methods described here can be applied with equal confidence in future through such undertakings using English language documents. [ABSTRACT FROM AUTHOR]

The paper deals with results of geological and geophysical study of the East Siberian Sea coastal areas are reported. Research activities started in 2018 in the frame of the State Geological Mapping Project (GK-1000/3) and continued in 2022 under support of the Russian Science Foundation. A seismo-stratigraphic scheme of the Quaternary sediment sequence has been compiled, and a conception of the paleogeographical evolution in the Late Pleistocene–Holocene has been proposed. [ABSTRACT FROM AUTHOR]

The Wadi Samra–Wadi Kid district in southeastern Sinai, Egypt, has undergone extensive investigation involving remote sensing analysis, field geology studies, petrography, and geochemistry. The main aim of this study is the integration between remote sensing applications, fieldwork, and laboratory studies for accurate lithological mapping for future mineral exploration in the study region. The field relationships between these coincident rocks were studied in the study area. Landsat-8 (OLI) data that cover the investigated area were used in this paper. The different rock units in the study area were studied petrographically using a polarizing microscope, in addition to major and trace analysis using ICP-OES tools. The Operational Land Imager (OLI) images were used with several processing methods, such as false color composite (FCC), band ratio (BR), principal component analysis (PCA), and minimum noise fraction (MNF) techniques for detecting the different types of rock units in the Wadi Kid district. This district mainly consists of a volcano-sedimentary sequence as well as diorite, gabbro, granite, and albitite. Geochemically, the metasediments are classified as pelitic graywackes derived from sedimentary origin (i.e., shales). The Al2O3 and CaO contents are medium–high, while the Fe2O3 and TiO2 contents are very low. Alkaline minerals are relatively low–medium in content. All of the metasediment samples are characterized by high MgO contents and low SiO2, Fe2O3, and CaO contents. The granitic rocks appear to have alkaline and subalkaline affinity, while the subalkaline granites are high-K calc-alkaline to shoshonite series. The alkaline rocks are classified as albitite, while the calc-alkaline series samples vary from monzodiorites to granites. The outcomes of this study can be used for prospecting metallic and industrial mineral exploration in the Wadi Kid district. [ABSTRACT FROM AUTHOR]

The paper's objective was to present the results of predicting the stiffness modulus of a recycled mix containing a blended road binder with foamed bitumen and emulsified bitumen. The Sm (acc. to IT-CY) indirect tensile test was used at temperatures of -10_C, 5°C, +13°C and +25°C. Prediction of the stiffness modulus accounted for the effect of temperature, the type of road binders, the sampling location and the type of technology selected. All effects, except temperature, were included in the model by entangling their effects through recycled base course physical and mechanical characteristics, such as indirect tensile strength, compressive strength, creep rate, air void content and moisture resistance. As a result, it was possible to determine a regression model based on multiple regression with a coefficient of determination R² = 0.78. Temperature and compressive strength were found to have the strongest effect on the variability of stiffness modulus. However, indirect tensile strength also significantly affected the Sm characteristic. In addition, FB-RCM (foamed bitumen) recycled mixtures proved to be more favourable than EB-RCM (emulsified bitumen) mixtures as they exhibited a lower deformation rate while retaining limited stiffness. [ABSTRACT FROM AUTHOR]

In tectonically active areas, such as the Italian peninsula, studying the faults responsible for strong earthquakes is often challenging, especially when the earthquakes occurred in historical times. In such cases, geoscientists need to integrate all the available information from historical reports, surface geology, and geophysics to constrain the faults responsible for the earthquakes from a seismotectonic point of view. In this paper, we update and review, according to the EMS-98 scale, the macroseismic fields of the five main events of the 1783 Calabria sequence (5, 6, and 7 February, 1 and 28 March, Mw 5.9 to 7.1), two other destructive events within the same epicentral area of the 1783 sequence (1791, Mw 6.1 and 1894, Mw 6.1), plus the Messina Strait 1908 earthquake (Mw 7.1). For the 1783 seismic sequence, we also elaborate an updated and new catalog of coseismic effects. The new macroseismic fields were analyzed using a series of MATLAB algorithms to identify (1) the unitarity of the field or its partitioning in sub-sources and (2) the field and sub-fields' main elongation. A collection of earthquake scale laws from literature was used to compute the average source parameters (length, width, and area) with their range of variability, and an elliptical map-view representation of the source geometry was calculated and made available. The analyses of such data allow us to speculate on the earthquakes/faults association, as well as propose new interpretations and reconstruct the space–time evolution of the significant southern Calabria seismic sequences in the last five centuries. [ABSTRACT FROM AUTHOR]

Thermal history modeling based on low-temperature thermochronological data is widely used in the study of geology. Despite its common applications, several problems remain easy to ignore yet should not be overlooked in the execution of such models. This paper describes four key problems of thermal history modeling, namely, (1) is the best-fit thermal history the best? (2) Is the date constraint box a suitable constraint? (3) Does the bimodal distribution of the apatite fission track confined track length absolutely correspond to the cooling reheating model? (4) Is the whole thermal history path credible? Counterexamples are then provided to stress the importance of accounting for these problems in the application of thermal history modeling. Acknowledging the uncertainty and considering the geological constraints are recommended to improve the accuracy of thermal history models. Moreover, thermal historical intervals with high credibility and strong constraint ability are recommended to interpret the selected geological phenomenon. [ABSTRACT FROM AUTHOR]

Rhenium, a unique and valuable metal with exceptional properties which is vital in various industrial applications, primarily found in conjunction with minerals like molybdenite and chalcopyrite, predominantly in western countries. Despite its rarity, understanding its geological distribution, geochemical characteristics, atomic structure, and behavior is essential. This paper provides a concise overview of the geological and geographical occurrences of rhenium, shedding light on its formation within both igneous and sedimentary environments. Additionally, it examines its economic significance, emphasizing its critical role in industries like aerospace, electronics, and petrochemicals due to its high-temperature resistance, corrosion resistance, and electrical conductivity enhancement. This comprehensive exploration highlights the importance of rhenium as a byproduct of mining, contributing significantly to technological advancements and innovation across various sectors. [ABSTRACT FROM AUTHOR]

The optimization and application of a new hyphenated procedure for iron ionic speciation, i.e., high performance liquid chromatography (HPLC) with short cation–exchange column (50 mm × 4 mm) coupled to high resolution inductively coupled plasma optical emission spectrometry (ICP hrOES), is presented in this paper. Fe(III) and Fe(II) species were separated on the column with the mobile phase containing pyridine–2,6–dicarboxylic acid (PDCA). The total time of the analysis was approx. 5 min, with a significantly low eluent flow rate (0.5 mL min−1) compared to the literature. Additionally, a long cation-exchange column (250 mm × 4.0 mm) was used as reference. Depending on the total iron content in the sample, two plasma views were chosen, e.g., an attenuated axial (<2 g kg−1) and an attenuated radial. The standard addition method was performed for the method's accuracy studies, and the applicability was presented on three types of samples: sediments, soils, and archaeological pottery. This study introduces a fast, efficient, and green method for leachable iron speciation in both geological and pottery samples. [ABSTRACT FROM AUTHOR]

The depletion of mining resources forces the mining industry to process more heterogeneous and complex orebodies. The inherent heterogeneity of these orebodies and their relation to processing recoveries have received considerable interest in recent years. The properties of ores, such as mineral composition and association, are known to affect flotation performance. Even ores with similar compositions can vary significantly regarding their texture, where the same minerals can occur in different forms. Therefore, very careful geometallurgical planning is needed to overcome the recovery losses. Glencore's Mount Isa Copper Operation has reported historical difficulties decreasing the copper losses associated with natural floatable pyrites. Understanding the rock properties of naturally floatable pyrites and how they relate to chalcopyrite losses is crucial for concentrator operations. The Mount Isa geometallurgy team is looking for proxies for predicting copper losses and natural floatable pyrites to improve mine planning. This paper presents an approach for predicting the collector-less flotation of pyrite, as well as chalcopyrite losses from rock properties. The statistical analysis between the rock quality and ore type gives an indication of the chalcopyrite losses and natural floatable pyrites, which has potential use in geometallurgy plans. [ABSTRACT FROM AUTHOR]

As a result of the continuous growth in the amount of geological data, machine learning (ML) offers an opportunity to contribute to solving problems in geosciences. However, digital geology applications introduce new challenges for machine learning due to the unique geoscience properties encountered in each problem, requiring novel research in ML. This paper proposes a novel machine learning method, entitled "Partial Decision Tree Forest (PART Forest)", to overcome these challenges introduced by geoscience problems and offers potential advancements in both machine learning and geoscience disciplines. The effectiveness of the proposed PART Forest method was illustrated in mineral classification. This study aims to build an intelligent ML model that automatically classifies the minerals in terms of their crystal structures (triclinic, monoclinic, orthorhombic, tetragonal, hexagonal, and trigonal) by taking into account their chemical compositions and their physical and optical properties. In the experiments, the proposed PART Forest method demonstrated its superiority over one of the well-known ensemble learning methods, random forest, in terms of accuracy, precision, recall, f-score, and AUC (area under the curve) metrics. [ABSTRACT FROM AUTHOR]

The Tuotuohe region is a highly prospective area for Pb and Zn mineral exploration. This paper contributes to our comprehension of the ore-controlling structures, fluid inclusions, and C–H–O–S–Pb isotope geochemistry of Pb–Zn deposits in this region. These deposits are generally hosted by carbonates and controlled by fractures. The principal homogenization temperatures of quart- and calcite-hosted inclusions ranged predominantly between 120 and 220 °C, with salinities varying from 6 to 16 wt.% NaCl equivalent. The Pb isotope compositions of the ore deposits are comparable to those of Cenozoic volcanic rocks in the region but differ significantly from those of the host rocks, indicating that the Pb within these deposits was derived from the mantle. The C, O, and S isotope compositions of samples exhibit a bimodal distribution based on whether they were derived from magma or host rocks, implying that magma-derived fluids underwent an isotopic exchange with the host rocks. The H-O isotope compositions of samples also indicate that ore-forming fluids were originally magmatic but were depleted by combining with meteoric water. These findings are also supported by variations in fluid inclusion homogenization temperatures and salinities. Taken together, these findings suggest that the Pb–Zn deposits of the Tuotuohe region developed from magma to hydrothermal fluids at medium–low temperatures. [ABSTRACT FROM AUTHOR]

1D velocity profiles at a strong motion station in the northern part of the Kumamoto plain, Japan, were submitted in Step-1 of the blind prediction exercise of strong ground motions in the sixth international symposium on effects of surface geology on seismic motion (ESG6). Individual participants were requested to estimate a 1D S-wave velocity profile of sedimentary layers from the given data obtained by microtremor array explorations and surface-wave explorations at the site. This paper reports the target site, methods used by the individual participants, and the submitted results. More than half of the participants estimated the phase velocities of the Rayleigh-wave in the frequency range from 0.53 to 29.8 Hz. The statistical analysis of the phase velocity dispersion curves indicates that the standard deviation was below 40 m/s at the frequencies above 3.4 Hz, and it was below 20 m/s above 20 Hz. The S-wave velocity profiles are also similar to a depth of 20 m. The standard deviation was below 45 m/s. The average S-wave velocity in the top 30 m from the surface is 207.3 ± 60.7 m/s for the submitted profiles. The large variation is related to the introduction of the near-surface low velocity layers. The large variation of the S-wave velocities was found in the deep part. The average S-wave velocity at a depth of 1500 m was 2674 m/s with the standard deviation of 786 m/s. We compared 1D amplifications for the submitted profiles. Common peaks can be identified at 0.3–0.4 Hz and 1–2 Hz, excluding two teams. However, the amplifications vary much in the frequency range higher than 4 Hz. Through the experiment, it was found that the dispersion curves and the shallow S-wave velocity structures are estimated with a low standard deviation among the participants. Further development of the techniques for deep S-wave velocity profiling was found to be required. [ABSTRACT FROM AUTHOR]

The present paper focuses on the geology, petrography, and geochemistry of the well-known Dokhan volcanics encountered in the northern part of the Eastern Desert of Egypt. The basalts, andesites, rhyolites, and agglomerates exposed at the Makhar Seal (flood plain) as well as Wadi Abu Zoghot, Wadi El-Ghafiryia, Wadi Al-Radah Luman, Wadi Al-Ushsh, Wadi Umm Sidrah, and Gabal Ghuwayrib are herein examined as sources of coarse aggregate in concrete mixes. A representative total of 28 samples—collected from different Dokhan volcanics—was studied in terms of field geology, petrography, and geochemistry wherein a variety of experiments related to construction material validation apply. The petrographic examination revealed that the studied Dokhan volcanics consist of basic, intermediate, and acidic volcanic igneous rocks. These rocks are represented through basalts, andesites, imperial porphyry, dacites, rhyodacites, rhyolites, and their pyroclastics. Furthermore, the applied geochemical analysis indicated that the studied Dokhan volcanics are alkaline to sub-alkaline, calc-alkaline and classified as basalts, basaltic andesites, andesites, trachyandesites, trachydacites, trachytes, and rhyolites, indicating an initial potential as aggregate for concrete mixes. Finally, the results obtained from incorporating Dokhan volcanics as aggregates in concrete mixes demonstrated a significant improvement in regard to the properties of the comprising concrete mixes. Herein, a higher compressive strength was witnessed after 28 days for Dokhan volcanic concrete, when compared to concrete comprising dolomite aggregate, amounting to an average increase that exceeded 36%. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated the potential of machine learning methods for fast and accurate mineral classification based on microscope thin sections. Such methods can be extremely useful to support geoscientists during the phases of operational geology, especially when mineralogical and petrological data are fully integrated with other geological and geophysical information. In order to be effective, these methods require robust machine learning models trained on pre-labeled data. Furthermore, it is mandatory to optimize the hyper-parameters of the machine learning techniques in order to guarantee optimal classification accuracy and reliability. Nowadays, deep learning algorithms are widely applied for image analysis and automatic classification in a large range of Earth disciplines, including mineralogy, petrography, paleontology, well-log analysis, geophysical imaging, and so forth. The main reason for the recognized effectiveness of deep learning algorithms for image analysis is that they are able to quickly learn complex representations of images and patterns within them. Differently from traditional image-processing techniques based on handcrafted features, deep learning models automatically learn and extract features from the data, capturing, in almost real-time, complex relationships and patterns that are difficult to manually define. Many different types of deep learning models can be used for image analysis and classification, including fully connected deep neural networks (FCNNs), convolutional neural networks (CNNs or ConvNet), and residual networks (ResNets). In this paper, we compare some of these techniques and verify their effectiveness on the same dataset of mineralogical thin sections. We show that the different deep learning methods are all effective techniques in recognizing and classifying mineral images directly in the field, with ResNets outperforming the other techniques in terms of accuracy and precision. In addition, we compare the performance of deep learning techniques with different machine learning algorithms, including random forest, naive Bayes, adaptive boosting, support vector machine, and decision tree. Using quantitative performance indexes as well as confusion matrixes, we demonstrate that deep neural networks show generally better classification performances than the other approaches. Furthermore, we briefly discuss how to expand the same workflow to other types of images and geo-data, showing how this deep learning approach can be generalized to a multiscale/multipurpose methodology addressed to the analysis and automatic classification of multidisciplinary information. This article has tutorial purposes, too. For that reason, we will explain, with a didactical level of detail, all the key steps of the workflow. [ABSTRACT FROM AUTHOR]

This paper analyzes the latest complete Bouguer gravity anomaly map of Slovakia in relation to geological architecture. The observed gravity field consists of regional and local gravity anomalies, as well as marked horizontal gravity gradients. The most remarkable regional feature on this map is the large field with low-density masses in the northern part of Central Slovakia (the so-called Western Carpathian gravity low), which is divided into two gravity sub-lows: the Outer and Inner Western Carpathian gravity low. The source of the first sub-low is the sediments of the Outer Western Carpathian flysch units, and the second one is a crust with prevailing granites and orthogneisses. It is suggested that this field is only the torso of the original one, which stretched along the entire length of Slovakia from the SW to the NE. However, in the youngest stages of tectonic development, the negative gravity anomalous field in the territory of West and East Slovakia changed to a positive one due to the thinning of the lithosphere and crust by the influence of asthenolithic masses from the mantle. The higher density masses in Central Slovakia south of the Carpathian gravity low are not caused only by asthenolithic action. The different tectonic segment with a predominance of metamorphic complexes and a higher average density, in comparison to the low-density granitized complexes in the north, also contributes to its manifestation. The boundary between these two segments in Central Slovakia is a linear and sharp tectonic zone and coincides with the extensive Pohorelá shear zone. Several local anomalies also occur on the complete Bouguer anomaly map, and they were also subjected to geological analysis. These include local areas with a predominance of heavier crust, such as the core mountains in western Slovakia, subvolcanic intrusions, metabasic complexes, and the Cadomian basements. Prominent horizontal gravity gradients reflect the tectonic interfaces (faults, shear zones) that originated mainly during the youngest period of the Western Carpathian tectonic development and were also interpreted. The faults shown in the complete Bouguer anomaly map were active mainly during the transpressional and extensional stage of the Neo-Alpine tectonic development. [ABSTRACT FROM AUTHOR]

The aim of the paper is to show a methodology in order to build a local geoid model using the Compute-Remove-Restore technique; to achieve this aim, suitable algorithms in Matlab® environment were developed. The knowledge of a geoid model assumes an important role in the field of engineering, geosciences and geomatics since that it allows the definition of physical heights or the components of the deflection of the vertical on a specific area. The area taken into consideration for the research is the Campania region (Italy). By comparing the geoid undulation values of the model developed in this paper with those extracted from the benchmarks over this area derived from the national levelling network, it is possible to obtain centimetre accuracy. [ABSTRACT FROM AUTHOR]

Geological reports are frequently used by geologists involved in geological surveys and scientific research to record the results and outcomes of geological surveys. With such a rich data source, a substantial amount of knowledge has yet to be mined and analyzed. This paper focuses on automatically information extraction from geological reports, namely, geological named entity recognition. Geological named entity recognition has an important role in data mining, knowledge discovery and Knowledge graph construction. Existing general named entity recognition models/tools are limited in the domain of geoscience due to the various language irregularities associated with geological text, such as informal sentence structures, several domain‐geoscience words, large character lengths and multiple combinations of independent words. We present Bidirectional encoder representations from transformers (BERT)‐(Bidirectional gated recurrent unit network) BiGRU‐ (Conditional random field) CRF, which is a deep learning‐based geological named entity recognition model that is designed specifically with these linguistic irregularities in mind. Based on the pretrained language model, an integrated deep learning model incorporating BERT, BiGRU and CRF is constructed to obtain character vectors rich in semantic information through the BERT pretrained language model to alleviate for the lack of specificity of static word vectors (e.g., word2vec) and to improve the extraction capability of complex geological entities. We demonstrate our proposed model by applying it to four test datasets, including a geoscience NER data set from regional geological reports, and by comparing its performance with those of five baseline models. Plain Language Summary: Geological named entity recognition has an important role in information extraction and knowledge discovery. This paper presents BERT‐BiGRU‐CRF, which is a deep learning‐based geological named entity recognition model that is designed specifically with these linguistic irregularities in mind. We hope that our approach will serve as an alternative method that deserves further study. Key Points: A named entity recognition model based on BERT‐BiGRU‐CRF is proposed and a set of detailed experimental tests on domain data setOur model is compared in detail with four other mainstream models, and experiments demonstrate that our model obtains better performanceWe share the source code of BERT‐BiGRU‐CRF and the annotated test data [ABSTRACT FROM AUTHOR]

Research on geodiversity has been increasing in recent years, both internationally and in Brazil. This theme refers to the abiotic elements of the planet and has been the subject of studies since the 1990s, having developed nationally in the early 2000s. This work analyzed the academic research on geodiversity and related themes carried out in Brazil from 2000 to 2021, through a systematic search and bibliometric research in libraries, institutional repositories, and digital collections of the 69 Brazilian Federal Universities (HEI) and in the Brazilian Digital Library of Theses and Dissertations (BDTD). We searched the terms ‘geodiversity’, ‘geoconservation’, ‘geoconservationist/s’, ‘geotourism’, ‘geopark/s’, ‘geopatrimony’, ‘geosite/s’ and ‘geological heritage’. It was found 209 papers in 36 universities distributed in all regions of the country, with emphasis on the Northeast region, with 73 research in 9 institutions, followed by the Southeast region (65 papers in 12 HEIs), South (51 papers in 6 HEIs), Center-West (13 research in 6 HEIs) and North (7 publications in 4 HEIs). Regarding the number of papers, the Federal Universities of Minas Gerais (25), Pernambuco (20), Ceará (18) and Rio Grande do Sul (16) stand out, with the predominant being Dissertations (106), followed by Theses (57) and Final Papers (46). Written since 2003, there was a significant increase as of 2012, with 2016 standing out, and a decrease in 2020. Regarding the frequency of use of the keywords selected in the research, ‘geodiversity’ and ‘geoconservation’ prevailed. We highlight the master’s and doctoral courses in Geography, and undergraduate courses in Geology. [ABSTRACT FROM AUTHOR]

In recent years, interest in geoheritage among scientists and the broader public alike seems to be growing. However, concern for geological heritage is relatively late, compared to that of living heritage. Actions for protections have long remained marginal. The increase in the number of views on this notion has gone along with a reflection on its meaning and a multiplication of the number of laws to accommodate situations and be able to take into account the diversity of possible cases. In this paper, after a historical review, we propose a synthesis of this notion of geoheritage, as it is currently underway in France. We support our point on specific examples, and especially those that have an echo at the international level: in stratigraphy, for example, with the list of stages based on French localities, as well as in petrography and mineralogy with the lithotypes or minerals whose name is linked to the territory. Finally, we deal with the legal aspects, which apply to objects (movable geoheritage), geosites, especially with recent developments because of these texts, and databases that govern the operation and current development of geoheritage. [ABSTRACT FROM AUTHOR]

The contribution of botany to the analysis of geological traces should not be neglected in forensic investigations. Small plant traces, especially if widespread in quantity, easily adhere to the subjects involved in criminal events. However, the identification of highly fragmentated plant structures often relies to skilled experts. The present paper deals with the morphological descriptions of thorns and similar plant appendices produced by the plants thriving in the area under investigation in a court case regarding the disappearance of two subjects in a rural area of the countryside. Comparative observations between unknown and known samples, related to victims and crime scene respectively, made it possible to identify traces found on the victims as plants thriving in the area under investigations. Basing on the punctual distribution of individual plants in the investigated territory, the results of the comparative analyses allowed to reconstruct the victims' path in the hours immediately preceding their death. Consequently, these data provided valuable information for implementing the geological investigation carried out for the judicial authority. [ABSTRACT FROM AUTHOR]

Ghana is a country exceptionally rich in geologic mineral resources with contrasting topographic relief and varied geophysical setting. This paper evaluated the geological and geophysical setting of Ghana with a special focus on the impact of the geologic setting and topography on gravity. Specifically, it assessed how variations in geology, topography, landscapes and the environment control the geophysical parameters and how these vary among the major regions of the country - the Volta Basin, Northern Plains, Ashanti-Kwahu (Kumasi) and Coastal Plains in the Accra surroundings. Previous studies utilizing traditional Geographic Information System (GIS) approaches have documented the geologic evolution of Ghana evolved as a part of the West African Craton. As a contribution to the existing research, this paper presents a regional analysis of Ghana by integrated mapping of geology, geophysics and topography of the country. The technical approach of this research focuses on utilizing the console-based scripting cartographic toolset Generic Mapping Tools (GMT) integrated with QGIS for processing and mapping the datasets: General Bathymetric Chart of the Oceans (GEBCO), Earth Gravitational Model 2008 (EGM-2008), gravity grids. The theoretical background is based on the geologic research of West Africa supported by high-resolution data. The paper defines a conceptual cartographic framework for integrated geologic and geophysical visualization in a regionalscale mapping project on Ghana. [ABSTRACT FROM AUTHOR]

This paper presents the recent advances made in Iran using the radio wave technique for ionospheric studies. The characteristics of the VLF signal transmitted from Turkey (26.7 kHz) and India (18.2 kHz) and received in Tehran are studied in detail to verify the behavior of signal and implement that for earthquake prediction and ionospheric remote sensing purposes. While several theories are proposed regarding the propagation of VLF, this paper aims to investigate the received signal along with the electron density variation and magnetic field strength along the propagation path. The observational data for 40 days is averaged over 24 hours with a 1-minute time resolution. The propagation of the VLF signal in the earth-ionosphere waveguide is studied by considering the electron density variation along the propagation path at several selected locations using the IRI (International Reference Ionosphere) model throughout the day. The IGRF (International Geomagnetic Reference Field) model is used to study the earth's magnetic field and the associated conductivities in the ionosphere. The excitation of secondary VLF waves in the lower ionospheric E region and propagation along the maximum conductivity is compared with the reflection from the ionosphere and propagation in the earth-ionosphere waveguide as the two different propagation mechanisms for the VLF signal. A conclusion on the propagation characteristic of the signal is made and several variation characteristics of the radio signal during the day are determined. [ABSTRACT FROM AUTHOR]

The geology of Eastern Himalaya, the Indo‐Myanmar orogenic belt (IMOB), the Shillong Plateau and its adjoining regions have a distinct entity in the tectonic framework of South‐east Asia. A considerable gap exists in our knowledge of the geology of the Eastern Himalaya, IMOB, Shillong Plateau, Assam–Arakan Basin, and ophiolites of Northeast India. In order to fulfil the gap to some extent two Special Issues were proposed through advanced interdisciplinary studies of geosciences. A total of 29 research papers cover articles of interdisciplinary studies of geosciences to understand the magmatism and exhumation history of the crystalline core, pressure, temperature, time, and deformation (P–T–t–d) conditions of the geologically least explored Eastern Himalaya and IMOB and adjoining regions are included in this Special Issue. This Special issue‐Part 2 is a continuation of an earlier Special Issue‐Part 1 published in vol. 57 (2), GJ with 26 research articles. This Special Issue will provide state‐of‐art information on the geodynamic evolution of the Eastern Himalaya and Indo‐Myanmar orogenic belt in the tectonic framework of South‐east Asia and will help in planning future guidelines to explore this one of the least studied geological terrains. Overall, this Special Issue will have the potential to become a reference volume for researchers, particularly working in the Eastern Himalaya, Shillong Plateau, Assam–Arakan Basin, and ophiolites of North‐east India. This volume will also be useful to future researchers and will also have the potential to become a reference volume for researchers, particularly working in the north‐eastern part of India and adjoining regions. [ABSTRACT FROM AUTHOR]

The development of deposits with a complex geological structures is often accompanied by a set of problems associated with optimal decision making. The efficiency of the entire development system depends on the completeness and the quality of the analysis of reservoir parameters. This paper presents methodological approaches for the study of carbonate deposits, and the development of further steps to increase the efficiency of reserve recovery. The secondary transformation of reservoir rocks, resulting in channels of increased conductivity, cracks, and caverns, plays a special role in the nature of the recovery of hydrocarbon reserves from such deposits. Secondary cavernosity leads to violations of the linear laws of fluid filtration in a porous medium, and complicates the field performance prediction based on geological and hydrodynamic modeling. The studied geological structure was detailed using the example of carbonate deposits composed of oil and water- saturated formations, taking into account the results of core studies and the interpretation of geophysical well studies. Furthermore, the parameters of production wells made it possible to confirm that the oil saturated and underlying water saturated formations have hydrodynamic connectivity due to the presence of vertical micro cracks. At the same time, the thickness of the bridge between the reservoirs directly affects the initial water cutting of well production, and further growth dynamics of the water ratio are associated with the structural factors determining the initial oil content of the reservoir. The combination of the obtained dependencies and the distribution model of the reservoir properties along the area made it possible to build a complex map reflecting the predicted development efficiency in certain areas. The integration of the results of various field studies on the injection well stock established that a significant part of the water flows was injected into the water saturated formation, which reduces the efficiency of formation pressure maintenance in the target formation. As a result, in order to reduce the low efficiency injection volume, switching to a more rigid waterflooding system, in terms of the ratio of production and injection wells, is proposed with a further decrease in the injection pressure inside the wells. [ABSTRACT FROM AUTHOR]

We are living in a data‐centric society, with governments and businesses increasingly looking at what they can do to gain insight and improve the flow of data. Encouraging the release of data as 'open data' is one measure that would remove barriers to access, increase use and facilitate downstream data innovation. Using examples from firstly the non‐geoscience and then geoscience sectors, this paper outlines three factors that can lead to a successful open data programme. These are (1) having a clear strategy with a well‐articulated vision; (2) ensuring that data are not only free but also technically accessible and delivered under an open licence; and (3) continued investment in the programme to ensure its long‐term success. However, not all data can or should be open, and organizations and governments must be careful that their interventions do not have unintended consequences that might reduce incentives to collect, maintain and share data. A primary concern is the financial sustainability of a dataset, but this also extends to other risks that would prevent the data being widely shared such as the inclusion of personal data or third‐party intellectual property. In these cases, use of a data‐sharing risk assessment framework, and the application of the FAIR principles of findable, accessible, interoperable and reusable can be used to increase data sharing and maximize the benefits that can be realized from geoscience data. [ABSTRACT FROM AUTHOR]

This paper quantifies rates of shoreline change and investigates the influence of surficial geology on shoreline dynamics between 1950 and 2018 on Pelly Island, located 10 km off the Mackenzie Delta. Long-term changes in shoreline position were calculated using imagery analysis and Analysing Moving Boundaries Using R (AMBUR). The influence of shoreline exposure to predominant storm direction and influence of surficial geology were examined for northwestern and southeastern zones. The average annual linear regression rate (LRR) rate during the 1950–2018 observation period was −3.8 m·a−1. The end point rate (EPR) was calculated for seven observation periods: 1950–1972, 1972–1985, 1985–2000, 2000–2018, 2000–2013, 2013–2018, and 1950–2018. A mean EPR of −5.5 ± 0.7 m·a−1 was calculated for the 2000–2018 period, and a maximum retreat rate of 46.7 ± 2.1 m·a−1 was recorded during the 2013–2018 observation period. By comparing the rate of change for sections of historical shorelines with differing surficial geology and exposure to storms, it was possible to draw conclusions on why Pelly Island continues to have the highest retreat rates in the Mackenzie–Beaufort region. Greater retreat rates were observed in lacustrine deposits (5.3 m·a−1) compared with moraine deposits (2.7 m·a−1). In addition, shoreline exposure to the predominant storm direction from the northwest was found to be a major influence on rates of shoreline change in all observation periods. [ABSTRACT FROM AUTHOR]

This article presents results for the development of new methods of inserting discontinuity lines into the numerical model of the deposit in CAD systems. The main problem in creating a numerical model of the deposit is usually a very small number, as well as low reliability of the source data. Hence, the authors developed new algorithms for inputting discontinuities, which can be used in particular for conditions when a large number of discontinuities are present. The article offers algorithms for inputting discontinuities into the entire deposit model. The method of transferring faults from the higher seam to subsequent seams and determining the course of the fault in the entire rock mass has been described. The fault can be represented as a spatial mesh of triangles, just like the seam floor. Then the fault can be extended until it intersects with the next seam (with the next triangle mesh) using geostatistical methods. As a result, we determine the exact position of the discontinuity line in the next seam. The paper also presents several algorithms for checking the deposit model made using the methods developed by the authors, including the analysis of outliers (in terms of elevation and inclination), testing the variability of the fault throw, checking the distance between adjacent seams, and verifying the position of the deposit in relation to the existing workings and boreholes. It should be noted that the key issue while building a deposit model is a checking of the model, removal of the assumptions and, obviously, incorrect data in order to obtain the highest possible accuracy. [ABSTRACT FROM AUTHOR]

In the last two decades, both the amount and quality of geoinformation in the geosciences field have improved substantially due to the increasingly more widespread use of techniques such as Laser Scanning (LiDAR), digital photogrammetry, unmanned aerial vehicles, geophysical reconnaissance (seismic, electrical, geomagnetic), and ground-penetrating radar (GPR), among others. Furthermore, the advances in computing, storage and visualization resources allow the acquisition of 3D terrain models (surface and underground) with unprecedented ease and versatility. However, despite these scientific and technical developments, it is still a common practice to simplify the 3D data in 2D static images, losing part of its communicative potential. The objective of this paper is to demonstrate the possibilities of extended reality (XR) for communication and sharing of 3D geoinformation in the field of geosciences. A brief review of the different variants within XR is followed by the presentation of the design and functionalities of headset-type mixed reality (MR) devices, which allow the 3D models to be investigated collaboratively by several users in the office environment. The specific focus is on the functionalities of Microsoft's HoloLens 2 untethered holographic head mounted display (HMD), and the ADA Platform App by Clirio, which is used to manage model viewing with the HMD. We demonstrate the capabilities of MR for the visualization and dissemination of complex 3D information in geosciences in data rich and self-directed immersive environment, through selected 3D models (most of them of the Montserrat massif). Finally, we highlight the educational possibilities of MR technology. Today MR has an incipient and reduced use; we hope that it will gain popularity as the barriers of entry become lower. [ABSTRACT FROM AUTHOR]

Geoscience is plagued with structural and systemic barriers that prevent people of historically excluded groups from fully participating in, contributing to, and accruing the benefits of geosciences. A change in the culture of our learning and working environments is required to dismantle barriers and promote belonging, accessibility, justice, equity, diversity, and inclusion in our field. Inspired by a session organized at the 2020 Ocean Sciences Meeting, the goal of this paper is to provide a consolidated summary of a few innovative, broadening participation initiatives that are being led by various stakeholders in academia and research sectors (e.g., students, faculty, administrative leaders) at different institutional levels (e.g., universities, professional societies). The authors hope that the strategies outlined in this paper will inspire the coastal, ocean, and marine science community to take individual and collective actions that lead to a positive culture change. [ABSTRACT FROM AUTHOR]

As the amount of published geoscience literature grows, reading and summarizing texts of large collections has become a challenging task. Publication keywords can be considered basic components of knowledge structure representations and have been used to reveal knowledge concerning research domains. In contrast to data used in other research domains, the works on textual geoscience data that entail keyword extraction are limited. In this paper, we propose an unsupervised algorithm, the graph‐based keyword extractor with error‐feedback propagation (GKEEP), that enhances graph‐based keyword extraction approaches by using an error‐feedback mechanism similar to the concept of backpropagation. The proposed approach comprises the following steps. A preprocessed document is used as the input of the proposed model and is represented as a weighted undirected graph, where the vertices represent words and the edges represent the cooccurrence relationship between the words constrained by a window size. Subsequently, its nodes are ranked by their importance scores calculated by a graph‐based ranking algorithm. Consequently, all the words have their own scores, and they are used to compute the scores of keyword candidates. Subsequently, the Word2Vec method is applied to recalculate the scores of keyword candidates and rank the keyword candidates to select the final keyword. It also utilizes error feedback to boost the rankings of the most salient terms that would otherwise be deemed less important. With empirical experiments on two real data sets (including our newly built data set), the proposed GKEEP model outperforms state‐of‐the‐art unsupervised models and the existing graph‐based ranking models. The proposed method can effectively reflect intrinsic keyword semantics and interrelationships. Plain Language Summary: The common or frequently used terms receive higher scores in traditional graph‐based extraction owing to there are more edges connected to them. This paper proposes a graph‐based KE algorithm called KE using error‐feedback propagation, which utilizes the semantics of word embedding to assist in extracting keywords from geoscience reports. We hope that our approach will serve as an alternative method that deserves further study. Key Points: Word embedding is incorporated to capture the dependency structure as well as the data distribution, and it computes semantic relations to solve the content sparsity problemError feedback is utilized to boost the most salient terms that graph‐based approaches deem less importantA set of experiments to verify the effectiveness of the proposed method on two available manually constructed data sets [ABSTRACT FROM AUTHOR]

Microseismic can build a bridge between engineering operations such as drilling and fracturing and stratum evaluation such as earthquake, geology, and logging by fully excavating fracture time, spatial development characteristics, and focal information. For the postseismic evaluation of microseisms, a comprehensive evaluation system integrating microseisms and multidisciplines is established in this paper: through deep excavation of microseismic information such as the time and space distribution of microseismic events, quantitative statistics, magnitude-frequency gradient (B -value) and S-P wave energy ratio (Es/Ep), the effective identification of dry faults, wet faults, cracks, joints, sweet spots and nonsweet spots is realized, combined with seismology and geology. The engineering problems (casing change, pressure change, fracturing barrier, etc.) are analyzed accordingly, which enhances the comprehensive evaluation function of microseismic and multidiscipline. [ABSTRACT FROM AUTHOR]

Ordinary chondrites are the most common type of chondrites. As a non-destructive, rapid, and semi-quantitative technology, Raman spectroscopy is widely used in geoscience. This paper presents the results of a Raman spectroscopic study that we conducted for 16 ordinary chondrites with different chemical groups and variable degrees of shock metamorphism. We found that: (1) the relationship between the Fe composition of olivine and pyroxene and the characteristic peaks of the Raman spectrum established by predecessors cannot be refined to the range of meteorites, the shock on meteorites also affects the Raman spectral characteristics of minerals and (2) the full width at half maximum (FWHM) of the shocked minerals (including high-pressure minerals) in meteorites increases in the Raman spectrum, however, no clear numerical relationship with pressure was found. Based on these data, we assess that the feasibility of Raman spectroscopy for the classification of chemical group and shock metamorphism in ordinary chondrites is not well established. [ABSTRACT FROM AUTHOR]

Crystalline basement rock aquifers underlie more than 20% of the earth's surface. However, owing to an inadequate understanding of geological structures, it is challenging to locate the groundwater resources in crystalline hard rock terranes. In these terranes, faults, fractures, and shear zones play an important role in bedrock weathering and ultimately groundwater storage. This study integrates important geological structures with 2D high-resolution subsurface resistivity images in understanding the factors that influenced bedrock weathering and groundwater. The results reveal the variability of weathered zone depth in different structural zones (Zone-I to Zone-IV). This is due to the presence of foliations, fractures, and faults. A thicker weathered zone develops when a fracture/fault overprints a pre-existing planar pervasive structure like foliations (Zone-II) as compared to zones only with faults/fractures (Zone-III). Further, the transmissivity of boreholes also shows relatively higher in Zone-II than Zone-III, which implies a good pact between different structural features and possible groundwater storage. The study also demonstrates the role of paleostress and different tectonic structures influencing the depth of the "Critical Zone". While the geology may vary for different structural terranes, the approach presented in this paper can be readily adopted in mapping bedrock weathering and groundwater resources in crystalline basement terranes globally. [ABSTRACT FROM AUTHOR]

Crystalline basement rock aquifers underlie more than 20% of the earth's surface. However, owing to an inadequate understanding of geological structures, it is challenging to locate the groundwater resources in crystalline hard rock terranes. In these terranes, faults, fractures, and shear zones play an important role in bedrock weathering and ultimately groundwater storage. This study integrates important geological structures with 2D high-resolution subsurface resistivity images in understanding the factors that influenced bedrock weathering and groundwater. The results reveal the variability of weathered zone depth in different structural zones (Zone-I to Zone-IV). This is due to the presence of foliations, fractures, and faults. A thicker weathered zone develops when a fracture/fault overprints a pre-existing planar pervasive structure like foliations (Zone-II) as compared to zones only with faults/fractures (Zone-III). Further, the transmissivity of boreholes also shows relatively higher in Zone-II than Zone-III, which implies a good pact between different structural features and possible groundwater storage. The study also demonstrates the role of paleostress and different tectonic structures influencing the depth of the "Critical Zone". While the geology may vary for different structural terranes, the approach presented in this paper can be readily adopted in mapping bedrock weathering and groundwater resources in crystalline basement terranes globally. [ABSTRACT FROM AUTHOR]

[Display omitted] • The hydrothermal titanite associated with Au mineralization was formed at 130.8 ± 0.63 Ma. • The early Cretaceous Au mineralization overprinted the Triassic and late Jurassic Mo-Pb mineralization in Huangshui'an. • The gold precipitation mechanisms are sulfidation, collection-redissolution by LMCE melt, and changes in f Te 2 and f S 2. Huangshui'an deposit, situated in the Xiong'ershan area of Qinling orogenic belt (QOB) in China, is a globally rare carbonatite-type molybdenum polymetallic deposit that contains economic Mo, Au, Pb, and REE mineralization. The molybdenite Re-Os ages (Ca. 213.5–209.2 Ma) indicates that Huangshui'an Mo mineralization formed at Late Triassic. However, it is still unclear whether the Au mineralization is related to carbonatite dykes, and the formation age and genesis mechanism of Au mineralization remain poorly understood at Huangshui'an. This paper presents a comprehensive investigation of the Au mineralization events at the Huangshui'an deposit, including geology, mineralogy, and geochronology. The aim is to provide insights into its formation and mineralization processes and offer a broader understanding of regional Au metallogeny. Based on petrographic investigations, four stages are identified in the Au mineralization as follows: (I) quartz-K-feldspar stage; (II) quartz-pyrite-gold stage, including (IIA) pyrite-native gold sub-stage and (IIB) gold-tellurite-bismuthide sub-stage; (III) quartz-pyrite-polymetallic sulphide-oxide stage; and (IV) calcite-quartz-chlorite stage. The LA-ICP-MS titanite U-Pb dating yields a weighted mean age of 130.8 ± 0.63 Ma which determined that the Au mineralization at Huangshui'an was in the Early Cretaceous and was an independent mineralization event, which may be related to the lithosphere's destructive effect on the North China Craton (NCC). Combined with mineralography by automatic quantitative mineral analysis and testing system (TIMA), we consider that tellurium-bismuth minerals are closely associated with Au mineralization. The sulfur and tellurium fugacity of the ore-forming fluids in each stage were calculated using metal sulfide-oxides and tellurium-bismuth minerals. It was concluded that the precipitation of Au in the Huangshui'an deposit was mainly due to the combined effects of sulfidation, gold collection-redissolution by the low-melting point chalcophile elements (LMCE) melts, and the variation of sulfur fugacity and tellurium fugacity. [ABSTRACT FROM AUTHOR]

Feature selection is an optional preprocessing procedure and is frequently used to improve the classification accuracy of a machine learning algorithm by removing irrelevant and/or redundant features. However, in many real-world applications, the test cost is also required for making optimal decisions, in addition to the classification accuracy. To the best of our knowledge, thus far, few studies have been conducted on test-cost-sensitive feature selection (TCSFS). In TCSFS, the objectives are twofold: 1) to improve the classification accuracy and 2) to decrease the test cost. Therefore, in fact, it constitutes a multiobjective optimization problem. In this paper, we transformed this multiobjective optimization problem into a single-objective optimization problem by utilizing a new evaluation function and in this paper, we propose a new general wrapper framework for TCSFS. Specifically, in our proposed framework, we add a new term to the evaluation function of a wrapper feature selection method so that the test cost of measuring features is taken into account. We experimentally tested our proposed framework, using 36 classification problems from the University of California at Irvine (UCI) repository, and compared it to some other state-of-the-art feature selection frameworks. The experimental results showed that our framework allows users to select an optimal feature subset with the minimal test cost, while simultaneously maintaining a high classification accuracy. [ABSTRACT FROM AUTHOR]

The South Sandwich Trench located eastward of the Drake Passage in the Scotia Sea between Antarctica and South America is one of the least studied deep-sea trenches. Its geomorphological formation and present shape formed under the strong influence of the tectonic plate movements and various aspects of the geological setting, i.e., sediment thickness, faults, fracture zones and geologic lineaments. The aim of this paper is to link the geological and geophysical setting of the Scotia Sea with individual geomorphological features of the South Sandwich Trench in the context of the phenomena of its formation and evolution. Linking several datasets (GEBCO, ETOPO1, EGM96, GlobSed and marine freeair gravity raster grids, geological vector layers) highlights correlations between various factors affecting deep-sea trench formation and development, using the Generic Mapping Tools (GMT) for cartographic mapping. The paper contributes to the regional studies of the submarine geomorphology in the Antarctic region with a technical application of the GMT cartographic scripting toolset. [ABSTRACT FROM AUTHOR]