E. A. Vlasov, A. G. Mochalov, M. F. Vigasina, V. D. Shcherbakov, P. Yu. Plechov
{"title":"Platinum Group Minerals of the Baimka Gold Placer Cluster, Western Chukotka: New Data","authors":"E. A. Vlasov, A. G. Mochalov, M. F. Vigasina, V. D. Shcherbakov, P. Yu. Plechov","doi":"10.3103/s0145875224700108","DOIUrl":"https://doi.org/10.3103/s0145875224700108","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of the study of the platinum group minerals of the Baimka gold placer cluster, Western Chukotka, Russia, are presented. Platinum group minerals belong to the iridium–platinum and platinum mineralogical-geochemical types with the Late Jurassic cumulative pyroxenite-gabbro complexes as a probable source. Platinum group minerals came to alluvial gold placers primarily from intermediate reservoirs, which is the Volgian volcanic-sedimentary sequence J<sub>3</sub>v<sub>2–3</sub>. Rounded silicate glass inclusions are a specific feature of platinum minerals from the Baimka placer cluster.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"41 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. F. Kopaevich, E. V. Yakovishina, N. O. Mitrofanova, A. M. Nikishin, S. I. Bordunov
{"title":"The Upper Maastrichtian Reference Section of Mt. Klementyev, Southeastern Crimea","authors":"L. F. Kopaevich, E. V. Yakovishina, N. O. Mitrofanova, A. M. Nikishin, S. I. Bordunov","doi":"10.3103/s0145875224700030","DOIUrl":"https://doi.org/10.3103/s0145875224700030","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of a comprehensive study of an Upper Maastrichtian reference Mt. Klementyev section (Southeastern Crimea), consisting of a terrigenous–carbonate sequence, are presented. It is established that sedimentation occurred in relatively deep-sea conditions. Biostratigraphic analysis of assemblages of benthic and planktonic foraminifers made it possible to recognize the foraminiferal zones in the section and to confirm deep-sea sedimentation during this period.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"43 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. M. Nikishin, S. G. Skolotnev, G. R. Foulger, E. A. Rodina, K. F. Aleshina, H. W. Posamentier, A. A. Chernykh
{"title":"Crustal Structure of the Mendeleev Rise in the Arctic Ocean: Synthesis of Seismic Profiles and Rock Sampling Data","authors":"A. M. Nikishin, S. G. Skolotnev, G. R. Foulger, E. A. Rodina, K. F. Aleshina, H. W. Posamentier, A. A. Chernykh","doi":"10.3103/s0145875224700017","DOIUrl":"https://doi.org/10.3103/s0145875224700017","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The Mendeleev Rise is located in the Amerasian Basin of the Arctic Ocean. The study synthesizes interpretations of regional seismic profiles of the 2D CDP seismic reflection method and rock survey data using special underwater vehicles on the slopes of seamounts and scarps. The rise is represented by alternating highs (horsts) and half-grabens. At the base of the horst sections, bright reflectors are distinguished, interpreted as volcanic rocks. The half-graben sections are wedge-shaped in section view and are similar in geometry to seaward-dipping reflectors (SDR) of continental passive volcanic margins. Rock sampling has shown that the horsts consist of the Paleozoic sedimentary rocks penetrated by intrusions. The Aptian–Albian sections with volcanics (basalts, trachybasalts, trachyandesites) were identified on the horsts. U/Pb dating of igneous rocks has showed that typical age of the rocks is 110–114 Ma. The Cretaceous igneous rocks contain zircons with ages ranging from the Pre-Barremian Mesozoic to Paleozoic and Precambrian. These zircons were captured by basaltic magma during its upward movement. The presence of these ancient zircons indicates that the Mendeleev Rise consists of the continental crust. A model of the crustal structure of the Mendeleev Rise is proposed. The base of the section visible on seismic profiles is characterized by predominance of volcanics (from basalts to trachyandesites on horsts and basically basalts in half-grabens). The upper and lower crust is approximately 20–30% replete with intrusions. At the base of the crust, a high-velocity layer up to 5 km thick is distinguished. It is assumed that its lower part is entirely represented by gabbro-type intrusions, and the upper part is the lowest part of the lower crust, maximally saturated with intrusions.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"103 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. S. Salavatova, D. A. Bychkov, R. V. Fiaizullina
{"title":"Mercury(II) Adsorption on the Maikop Series Rocks and Mud Volcano Clays","authors":"D. S. Salavatova, D. A. Bychkov, R. V. Fiaizullina","doi":"10.3103/s014587522470011x","DOIUrl":"https://doi.org/10.3103/s014587522470011x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The acid–base properties of the surface of Maikop series clays and mud volcano clays, as well as their adsorption properties with respect to mercury(II) ions, were studied. It is shown that pH<sub>PZC</sub> for the former is 7.1 on average; for the latter, 9.0. The pH<sub>PZC</sub> value for mud volcano clays is consistent with the pH values in the waters of mud volcanoes of the Kerch–Taman region. When the mass ratio of the sorbent and solution is 1 : 900, adsorption equilibrium occurs after 4 days with active stirring. Experimental data on mercury adsorption from NaCl–NaHCO<sub>3</sub> solution on natural sorbents are best described by the Redlich–Peterson and Toth equations. The process of mercury adsorption on clays of the Maikop series is more intense than that on mud volcano clays.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"58 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Algorithms of Deep Kinematic Migration in Two-Dimensional Media","authors":"P. Yu. Stepanov, J. A. Gomanyuk","doi":"10.3103/s0145875224700133","DOIUrl":"https://doi.org/10.3103/s0145875224700133","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The paper considers four kinematic migration algorithms (procedures for converting the arrival times of reflected waves to the Earth’s surface into the depths of reflectors) using medium-velocity and reservoir velocity models of layered media: a standard algorithm for converting times to depths through average velocities; a modified medium-velocity algorithm that takes into account the slope of seismic boundaries; an algorithm for layer-by-layer recalculation of <i>t</i><sub>0</sub> lines to depths; and a variational kinematic migration algorithm based on ray tracing theory using an integrating a system of differential equations with specified initial conditions by the Runge–Kutta method. To study the possibilities and limitations of each algorithm, calculations were carried out using number of theoretical models of layered media that approximate real geological conditions. Based on the results of numerical experiments using the four kinematic migration algorithms considered in the paper, conclusions were drawn about the efficiency of using each of the algorithms to reconstruct the geological boundaries in models of media with varying complexity.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"41 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. V. Eniosova, T. N. Lubkova, R. A. Mitoyan, V. K. Singh
{"title":"Chemical Composition of Christian and Pagan Metal Antiquities from Excavations at Medieval Novgorod on the Base of Interdisciplinary Research","authors":"N. V. Eniosova, T. N. Lubkova, R. A. Mitoyan, V. K. Singh","doi":"10.3103/s0145875224700121","DOIUrl":"https://doi.org/10.3103/s0145875224700121","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>This paper focused on the new chemical data of the 94 Christian and pagan metal artifacts, which have been found at the excavation of Medieval Novgorod and the Novgorod region. These data were obtained using the EDXRF nondestructive method within an interdisciplinary research project. Most artifacts are pendant crosses; round pendants and mounts with saints, fragments of church polycandelons, and pagan pendant amulets. The results have been statistically processed. Tin–lead bronzes are clearly predominant. There are also mixed copper alloys (gunmetal) with tin, zinc, and lead, and lead brass. The proportions of silver and lead–tin alloys, as well as pure tin and lead, are modest. These data, supplemented by subsequent Pb isotope and ICP-MS studies, and their geological interpretation will make it possible to reveal possible sources for the metals of the Novgorod artifacts.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"25 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Some Features of the Geological Structure of the Sediments around Bennett Island from Very-High-Resolution Seismic Data","authors":"G. Li, V. G. Gainanov, A. S. Zverev","doi":"10.3103/s0145875224700145","DOIUrl":"https://doi.org/10.3103/s0145875224700145","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The paper presents some processing and interpretation results of the very-high-resolution seismic data, acquired during the <i>RV</i> Academic Mstislav Keldysh cruise to Bennett island in the Russian Arctic. The purpose of investigations was to study underwater geological structures around the island, presence or absence of their connection to the ancient rocks on the surface of the island. Interpretation of the seismic data gives some clues to these questions.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"126 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. M. Bugrova, M. R. Latypova, L. F. Kopaevich, A. V. Gusev
{"title":"Foraminifera from Clay Pulp of the Semigorsky, Andrusov, and Borukh-Oba Mud Volcanoes in the Kerch–Taman Region","authors":"E. M. Bugrova, M. R. Latypova, L. F. Kopaevich, A. V. Gusev","doi":"10.3103/s0145875224700042","DOIUrl":"https://doi.org/10.3103/s0145875224700042","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The stratigraphy of the Kerch–Taman region has been refined based on foraminiferal assemblages from the clay pulp of the Semigorsky, Andrusov, and Borukh-Oba mud volcanoes. Comparison with the fauna from the reference section of the Paleogene along the Belaya River (Republic of Adygea) enabled us to reveal deposits of the Middle Eocene (Cherkessk and Kuma formations of the Lutetian and Bartonian stages); Lower Oligocene (Pshekha Formation, Rupelian Stage), confirmed by finds of remains of pteropods; and Middle Miocene (Konkian and Sarmatian stages of the Eastern Paratethys regional scale of the Miocene). Cretaceous deposits (Semigorsky Volcano) are attributed to the Late Campanian–Maastrichtian.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"22 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Elemental Composition of Bottom Sediments and Permafrost Deposits from Buor-Khaya Bay (Laptev Sea)","authors":"A. S. Ulyantsev, N. V. Polyakova","doi":"10.3103/s0145875224700054","DOIUrl":"https://doi.org/10.3103/s0145875224700054","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The paper summarizes data on the lithological and elemental composition of bottom sediments and permafrost from boreholes 1D-14, 3D-14, and 1D-15 drilled from shore ice in Buor-Khaya Bay in 2014–2015. Based on the determined percentage content of SiO<sub>2</sub>, Al<sub>2</sub>O<sub>3</sub>, Fe<sub>2</sub>O<sub>3</sub>, TiO<sub>2</sub>, MgO, Na<sub>2</sub>O, K<sub>2</sub>O, CaO, MnO, P<sub>2</sub>O<sub>5</sub>, Cl, Cr, S, Ni, Cu, Zn, Rb, Sr, Ba, Y, Zr, and C<sub>org</sub> in sediments, the values of lithochemical moduli were calculated, and a comparative analysis of the lithological and geochemical composition was performed. Differences in the lithochemical composition between the coastal (1D-14 and 3D-14) and relatively distant (1D-15) strata were shown, explained by the spatiotemporal variability of sedimentary fluxes and the weathering crust activity in the studied area of the Laptev Sea. Based on the geological structure, the obtained data on the lithochemical composition of thawed and permafrost deposits indicated that sedimentary rocks in the Kharaulakh Ridge of the Verkhoyansk mountain system, corresponding to sandstones, siltstones, and mudstones, were probably the basis of the petrofund. The contribution of igneous and metamorphic rocks to the supply of sedimentary matter in the strata uncovered by drilling was insignificant and of a subordinate nature.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"30 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. A. Potashev, V. V. Baushin, A. B. Mazo, R. G. Ramazanov, V. V. Shelepov
{"title":"Design of the Position of the Blocking Material in a Water-Flooded High-Permeability Interlayer of an Oil Reservoir for a Five-Spot Flooding Scheme","authors":"K. A. Potashev, V. V. Baushin, A. B. Mazo, R. G. Ramazanov, V. V. Shelepov","doi":"10.3103/s0145875224700169","DOIUrl":"https://doi.org/10.3103/s0145875224700169","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The article presents a comparative analysis of the efficiency of various arrangements of a blocking material in a thin, high-permeability water-cut layer of an oil reservoir in order to reduce unproductive injection and increase oil recovery. The efficiency was was calculated by high-resolution numerical simulation in the vertical section of a typical stream tube for a five-spot water-flooding scheme. Three types of position of the blocking intervals are considered for two representative ratios of the viscosity of the water and oil phases.</p>","PeriodicalId":44391,"journal":{"name":"Moscow University Geology Bulletin","volume":"21 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}