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Structural and geochemical features of coal‑bearing sediments and sources of rare element impurities in coals of the Rakovka depression,Primorsky Krai,Russia

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International Journal of Coal Science & Technology 2022年第1期9卷 71-83页

作者： Nikita Popov Igor Chekryzhov Irina Tarasenko Sergery Kasatkin Aleksei Kholodov Far East geological institute FEB ras VladivostokRussian Federation

There are known brown coal deposits in Primorsky Krai(Russian Federation),where coals contain rare elements(Ge,U,REE,etc.)up to industrial *** of the known metalliferous coals is the Rakovka coal-bearing depression,located on the southern edge of the Khanka(Prikhankaiskaya)Lowland,with an area of about 70 ***-metal granites with a developed weathering crust are spread in its basement and *** structural conditions forming the depression were studied using measurements of orientations of structural elements(layering,contacts,veins,and dikes)with regard to kinematic conditions of *** coal and host rocks were sampled in sections in the cross strike of the coal *** and dikes cutting them were sampled by separate rock chip *** chemical composition and element content were determined for all *** was found that the adjacent rocks played a major role in the formation of the Rakovka rare-metal-coal *** rare-elements enrichment is not associated with active tectonics,faults,and hydrothermal sources,as was previously ***,it was caused by the hydrogenic and clastogenic removal of these metals from the weathering crust of granites of the depression's flanks and argillated basite dikes cutting the *** hydrogenic nature of the anomalous accumulation of U in sorbed form on organic matter of coals is confirmed by the predominant enrichment of low-ash *** earth elements entered coal seams both in mineral and dissolved forms.A model of REE and uranium input into the coal-bearing sediments of the Rakovka depression was proposed.

关键词： REE Rare metal-coal deposit Accumulation pattern Tectonics

Ammoniteand bivalve-based biostratigraphy and Panboreal correlation of the Volgian Stage

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Science China Earth Sciences 2009年第12期52卷 1890-1909页

作者： ROGOV Mikhail ZAKHAROV Victor geological institute of ras Pyzhevski lane 7 Moscow 119017 Russia

The current ammonite- and buchiid-based biostratigraphical successions of the Volgian Stage are outlined, with an analysis of the most important data that support correlation throughout the Panboreal Superrealm. Updated ammonite zonal schemes were proposed for the Volgian of the type region (the Russian Platform) and Svalbard. The lower Volgian successions in all areas except the Russian Platform, with its eudemic virgatitid lineage and Submediterranean faunal elements, were dominated by Pectinatites and Eosphinctoceras-Subdichotomoceras. The last two genera were especially common eastwards from the Ural Mountains. During the middle Volgian, provincialism developed quickly within the ammonites, and unified assemblages with early Palvovia and Dorsoplanites at the base of the substage were replaced by numerous local eudemic faunas. Despite this, migrations of species of Crendonites, Laugeites, Epivirgatites Epipallasiceras, Epilaugeites, and Taimyrosphinctes occurred at regular intervals and these enable precise correlations between the faunal sub-provinces. The zonation of the upper Volgian is mainly based upon the succession of Craspedites (on Subcraspedites in England and North Sea), and can be traced throughout the Arctic. Zonation based on the bivalve Buchia enables correlations to be made between the successions over much of the Northern Hemisphere, including Northern California, British Columbia, Arctic areas, and the Russian Platform. Each substage of the Volgian is characterized by buchiids with different types of the ontogenetic development. Research on the infrazonal subdivision of the Volgian Stage based on buchiids is currently in progress. Our analyses of the ammonite and buchiid successions of the Panboreal Superrealm lead us to conclude that there are no major faunal gaps in Volgian successions of the Russian Platform and Northern Siberia.

关键词： Volgian Portlandian Panboreal Superrealm ammonites buchiids correlation.

3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology,reflection seismics,magnetotellurics and density modelling:Geodynamic speculations

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Geoscience Frontiers 2020年第3期11卷 999-1023页

作者： Michael V.Mints Victor N.Glaznev Olga M.Muravina Elena Yu Sokolova geological institute RASMoscowRussia Voronezh State University VoronezhRussia Schmidt institute of Physics of the Earth RASMoscowRussia All-Russian Research geological Oil institute MoscowRussia

A 3D model of deep crustal structure of the Archaean Karelia Craton and late Palaeoproterozoic Svecofennian Accretionary Orogen including the boundary zone is *** model is based on the combination of data from geological mapping and reflection seismic studies,along profiles 1-EU,4 B,FIRE-1-2 a-2 and FIRE-3-3 a,and uses results of magnetotelluric soundings in southern Finland and northern Karelia.A seismogeological model of the crust and crust-mantle boundary is compared with a model of subhorizontal velocity-density layering of the *** TTG-type crust of the Palaeoarchaean and Mesoarchaean microcontinents within the Karelia Craton and the Belomorian Province are separated by gently dipping greenstone belts,at least some of which are *** structure of the crust was determined mainly by Palaeoproterozoic tectonism in the intracontinental settings modified by a strong collisional compression at the end of the *** insights into structure,origin and evolution of the Svecofennian Orogen are *** accretionary complex is characterized by inclined tectonic layering:the tectonic sheets,~15 km thick,are composed of volcanic-sedimentary rocks,including electro-conductive graphite-bearing sedimentary rocks,and electro-resistive granitoids,which plunge monotonously and consecutively *** reaching the level of the lower crust,the tectonic sheets of the accretionary complex lose their distinct *** the seismic reflection pattern they are replaced by a uniform acoustically translucent medium,where separate sheets can only be traced *** crust-mantle boundary bears a diffuse character:the transition from crust to mantle is recorded by the disappearance of the vaguely drawn boundaries of the tectonic sheets and in the gradual transition of acoustically homogeneous and translucent lower crust into transparent *** the effect of endogenic heat flow,the accretionary complex underwent high-temperatu

关键词： Reflection seismics Magnetotellurics Svecofennian accretionary Orogen Svecofennian Ocean 3D crustal model Velocity-density layering

Geochemistry and petrology of superpure quartzites from East Sayan Mountains, Russia

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Acta Geochimica 2019年第1期38卷 22-39页

作者： A.M.Fedorov V.A.Makrygina A.I.Nepomnyaschikh A.P.Zhaboedov A.V.Parshin V.F.Posokhov Yu.V.Sokolnikova A.P.Vinogradov institute of Geochemistry SB ras Irkutsk National Research Technical University Irkutsk Scientific Center SB ras Irkutsk State University geological institute SB ras

Quartzites are widespread within Earth's lithosphere, but their highly pure varieties occur quite infrequently. With the development of alternative energy sources, including solar, and with increasing demand for high-purity quartz for optics, interest has risen in highpurity silicon-bearing materials. The quartzites discovered in the southeast part of the Eastern Sayan Mountains are particularly attractive for exploration in terms of their raw material quality and feasibility to be enriched. For this reason, their genesis also merits study. Available geochemical data show that chemogenic(d^(18)O>29.2%)siliceous-carbonate sediments of the Irkut Formation are fairly pure(impurity elements 0.9% impurities, but later, under the action of sliding slabs of ophiolite dynamothermal treatment reduced impurities to < 100 ppm, resulting in ‘‘superquartzites' '(highly pure quartzites). The presence of only minor structural impurities is due to the enrichment capacity of superquartzites to 10.1 ppm(7.2 ppm under special conditions) of 10 elements: Fe, Al, Ti, Ca, Mg, Cu,Mn, Na, K, and Li.

关键词： High-purity quartz Superquartzite Gravitational sliding Dynamic metamorphism Recrystallization

Chromite in the Mantle Section of the Oman Ophiolite: Implications for the Tectonic Evolution of the Oman Ophiolite

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Acta Geologica Sinica(English Edition) 2015年第A02期89卷 77-78页

作者： SAVELYEVA G.N BATANOVA V.G geological institute ras Moscow institute Geochemistry ras Moscow and ISTerre Universite Joseph Fourier Grenoble

Structure and composition of the Uralian ophiolites reflect a large spectrum of geodynamic environment of their creation during Paleozoic time： from mid-ocean ridge, rift zone in continental margin, and suprasubduction spreading zone （SSZ） with resultant lherzolite or harzburgite ophiolite type （LOT and HOT）.

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Intraspecific Variability and Problematic Dimorphism in the Early Cretaceous(Valanginian)Ammonite Saynoceras verrucosum(d'Orbigny,1841)

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 877-882页

作者： Izabela PLOCH Polish geological institute Geological Museum

The population of Saynoceras verrucosum （d＇Orbigny） from the Polish basin （Wawal section, central Poland） shows no significant intraspecific variability. Dimorphism has not been found in this population. Statistical analyses of material from the shallow epicratonic Polish basin and the relatively deep Vocontian basin （southeastern France） indicated two populations. Forms from the Polish basin are somewhat more inflated and smaller than forms from the Vocontian basin.

关键词： intraspecific variation Saynoceras verrucosum dimorphism Central Poland Wawal Section

Genesis and Distribution of Ultra-alkaline Magmatism within the East Antarctic Associated with the Kerguelen Plume Activity

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 198-199页

作者： Nadezhda M.Sushchevskaya Boris V.Belyatsky Robert Sh.Krymsky Vernadsky institute of Geochemistry RAS Karpinsky geological institute (VSEGEI)

Alkaline magmatism is often associated with the initial or final stages of huge plume *** alkaline bodies are most often found within the boundary area of plume impact upon the *** initial stages of the

关键词： Genesis and Distribution of Ultra-alkaline Magmatism within the East Antarctic Associated with the Kerguelen Plume Activity Jetty

Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 467-500页

作者： Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models Duc-Dam Nguyen Nguyen Viet Tiep Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham Faculty of Civil Engineering University of Transport TechnologyThanh XuanHa Noi100000Vietnam Faculty of Hydraulic Engineering Hanoi University of Civil EngineeringHa Noi100000Vietnam DDG(R)geological Survey of India Gandhinagar382010India Research institute of the University of Bucharest Bucharest050663Romania National institute of Hydrology and Water Management Bucharest013686Romania Department of Civil Engineering Transilvania University of BrasovBrasov500152Romania Danube Delta National institute for Research and Development Tulcea820112Romania Marwadi University Research Center(MURC) Marwadi UniversityRajkotGujaratBharat360003India Department of Civil Engineering Faculty of Engineering&TechnologyMarwadi UniversityRajkotGujaratBharat360003India

This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and ***,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and *** models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to *** factors were instrumental in predicting the output variable,which was the probability of landslide *** analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other *** AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of *** results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making.

关键词： Landslide susceptibility map spatial analysis ensemble modelling information values(IV)

Chemical geothermometry:application to mud volcanic waters of the Caucasus region

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Frontiers of Earth Science 2020年第4期14卷 738-757页

作者： Olga E.Kikvadze Vasilii Yu.Lavrushin Boris G.Polyak geological institute Russian Academy of SciencesMoscow119017Russia Siberian Branch of the ras V.S.Sobolev Institute of Geology and MineralogyNovosibirsk630090Russia

The generation temperatures of gas-water fluids released from mud volcanoes in different provinces of the Caucasian region have been constrained using Mg/Li(T_(Mg/Li))chemical *** volcanic fluids in the Taman Peninsula(Kerch-Taman mud volcanic province)were generated at temperatures(T_(Mg/Li))from 41℃ to 137℃.The depths of the respective mud reservoirs estimated from T_(Mg/Li) values and local geothermal gradient are in a range of 1.0 to 3.4 km which spans the Maykop Formation of marine *** the South Caspian province,the T_(Mg/Li) values of waters vary from 18℃ to 137℃ and the respective root depths HMg/Li of mud volcanoes range from∼0.85 to 6.5 *** obtained T_(Mg/Li) values for the analyzed mud volcanic waters from Caucasian provinces are in positive correlation with HCO3^(−)contents and water oxygen isotope compositions(δ^(18)OH_(2)O andΔδ^(18)OH_(2)O)and in high negative correlation with Cl^(−).The increase of T_(Mg/Li) toward the Greater Caucasus Range,as well as the lateral T_(Mg/Li) patterns in the Taman and South Caspian mud volcanic provinces,support the idea that mud volcanic fluids generate at temperatures increasing progressively toward the Alpine orogenic belt.

关键词： mud volcano fluid chemical geothermometry stable isotopes Caucasus region