Doklady Earth Sciences最新文献

{"title":"New Data on the Sm–Nd Age of Mafic/Ultramafic Intrusions on the Western Slope of the Southern Urals","authors":"S. G. Kovalev, S. S. Kovalev, A. A. Sharipova, V. M. Gorozhanin, A. V. Maslov","doi":"10.1134/s1028334x24602621","DOIUrl":"https://doi.org/10.1134/s1028334x24602621","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>This work presents new data on the Sm–Nd age of the Ishlya (1470 ± 62 Ma) and Misaelga (1481 ± 58 Ma) mafic/ultramafic complexes distributed along the western slope of the Southern Urals. The ages obtained are close to the Calymmian–Ectasian boundary (~1400 Ma) of the International Chronostratigraphic Scale. Based on calculated data, it is shown that the area of magma generation for the melts that formed the named complexes has been located in the “head” of a plume, which is the primary cause of the Mashak “magmatic event” in the Southern Urals.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"44 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141524896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemical Aspects of the Technology for Restoration of Vegetation Cover on Industrially Polluted Peat Soil Using Serpentine Materials","authors":"M. V. Slukovskaya, A. G. Petrova, L. A. Ivanova, I. A. Mosendz, T. K. Ivanova, S. V. Drogobuzhskaya, A. I. Novikov, A. A. Shirokaya, I. P. Kremenetskaya","doi":"10.1134/s1028334x24602578","DOIUrl":"https://doi.org/10.1134/s1028334x24602578","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Factors influencing the geochemical migration of elements during the development of artificial phytocenoses on industrially polluted peat soil with a high level of copper and nickel content using serpentine-containing materials are considered. Monitoring of the remediation sites during a four-year field experiment showed that the grass cover is capable of sustainable functioning by neutralizing the acidity of peat soil, reducing the toxicity of soil solutions, and eliminating the imbalance of macronutrients. Serpentine minerals act as an alkaline barrier, reducing the intensity of migration of copper and nickel compounds.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"35 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141524890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acceleration of Climate Change in the Upper Layer of the Black Sea","authors":"G. K. Korotaev, V. N. Belokopytov, V. L. Dorofeev, A. I. Mizyuk, A. L. Kholod","doi":"10.1134/s1028334x24602797","DOIUrl":"https://doi.org/10.1134/s1028334x24602797","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The thermohaline regime trends of the Black Sea basin in the period 2000–2021 were studied based on the data from three retrospective analyses (reanalyses) of the hydrophysical fields of the Black Sea. It is shown that the cumulative effect of an increase in the average sea surface temperature (SST) and increasingly milder winter conditions in the Black Sea over the last seven to eight years led to a record-breaking warming and then to the disappearance of the ventilated cold intermediate layer (CIL) of the Black Sea in its traditional meaning by 2020. In addition, in the past seven to eight years, accelerated warming of seawaters has been observed within the permanent (main) pycnocline. Changes in the thermal regime of the upper layer of the sea are accompanied by a continuing increase in salinity in the main pycnocline.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"43 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141524894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Crystal Structure of a Mineral with the Composition Pd(Bi,Sb)","authors":"A. A. Mezhueva, O. V. Karimova, L. A. Ivanova, N. D. Tolstykh, A. A. Zolotarev, N. N. Eremin","doi":"10.1134/s1028334x24602682","DOIUrl":"https://doi.org/10.1134/s1028334x24602682","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A mineral with the composition Pd(Bi_0.53Sb_0.47), intermediate between sobolevskite, ideally PdBi, and sudburyite, PdSb, from the Chineiskii Deposit (Transbaikal region, Russia), was studied by the SEM and XRD methods. Its crystal structure was solved and refined (<i>R</i> = 3.02%) based on single crystal X-ray diffraction data. The structure is orthorhombic, and the space group is <i>Cmcm</i>. The unit-cell parameters are <i>a =</i> 4.1465(4) Å, <i>b =</i> 7.1782(6) Å, <i>c =</i> 5.6843(4) Å, <i>V</i> = 169.19(2) ų, <i>Z</i> = 2. The series of the structures β-PdBi–Pd(Bi_0.53Sb_0.47)–PdSb and sobolevskite–sudburyite are discussed.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"20 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141531939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isotope (δ18О, δ13С, δD) Characteristics of Biotite–Carbonate–Quartz Associations of Hydrothermal Veins in Metabasites of North Karelia","authors":"I. S. Volkov, E. O. Dubinina, S. A. Kossova, Y. N. Chizhova, Y. O. Larionova, V. M. Kozlovskii, A. N. Pertsev","doi":"10.1134/s1028334x24602566","DOIUrl":"https://doi.org/10.1134/s1028334x24602566","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>On the White Sea islands and coast of North Karelia, in the Chupa sector of the Belomorian mobile belt (BMB), carbonate–silicate and quartz veins are localized in bodies of Early Proterozoic metabasites and their contacts with host gneisses. The isotopic characteristics of coarse crystal vein carbonates (δ¹⁸O and δ¹³C), as well as associated quartz (δ¹⁸O) and biotite (δ¹⁸O and δD), were studied. The isotopic composition of oxygen suggests biotite–quartz–carbonate equilibria during the formation of veins at temperatures of 520–450°C. The O and H isotopic characteristics of biotite correspond to the equilibrium of the fluid with metamorphic rocks. At the same time, the isotopic compositions of O and C carbonates indicate different CO₂ sources in fluids. There are three groups of carbonates according to δ¹⁸О and δ¹³С. The first group shows “magmatic” isotopic characteristics of the CO₂ source (δ¹⁸О_VSMOW = 7.1…12.1‰; δ¹³С_VPDB = –6.3…–4.5‰). Carbonates of the second group have high δ¹⁸О and δ¹³С, characteristic of Precambrian sedimentary carbonates (δ¹⁸О_VSMOW = 21.9…24.7‰; δ¹³С_VPDB = –2.2…–2‰), similar to those described earlier in the neighboring Engozero sector of the BMB. In the third group, the δ¹³С values are similar to the carbonates of the first group, and δ¹⁸О, to the second group (δ¹³С_VPDB = –1.7…0.9‰, δ¹⁸О_VSMOW = 6…12‰). The O and C isotopic compositions of carbonates of the third group can be obtained from the action of a putative magmatic fluid on both the primary sedimentary source of metamorphic fluids and redeposited vein carbonates.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"48 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141524936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Basalts of the Riphean Sequences of the Bashkirian Meganticlinorium, South Urals: New 147Sm‒143Nd and Rb‒Sr ID-TIMS Isotopic Constraints","authors":"V. N. Puchkov, Yu. L. Ronkin, N. D. Sergeeva","doi":"10.1134/s1028334x24602372","DOIUrl":"https://doi.org/10.1134/s1028334x24602372","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The first results of ¹⁴⁷Sm‒¹⁴³Nd and Rb‒Sr ID-TIMS isotopic–geochronological results of a comparative study of 12 samples of volcanic rocks of the Bashkirian Meganticlinorium, which were previously dated by zircons from these samples using the U‒Pb SHRIMP-II method showing the predominance of the Paleozoic ages among three stratigraphic levels with Riphean magmatic events in the South Urals, are presented. New ¹⁴⁷Sm‒¹⁴³Nd and Rb‒Sr ID-TIMS isotopic data showed that the volcanic rocks evolved as a result of crustal–mantle interaction. The Nd model ages (<i>T</i>_DM) (2302–2540 Ma) of volcanic rocks of the Taratash Anticlinorium represent the ages of the protolith characterized by ε_Nd(<i>t</i>) values from –17.4 to –20.5. The <i>T</i>_DM value (2033 Ma) of the Paleozoic volcanic rocks of the Yamantau Anticlinorium indicates a younger (Paleoproterozoic) substrate. The minimum Nd model ages (<i>T</i>_DM = 1160–1233 Ma) are determined for the volcanic rocks, which are spatially related to metabasalts of the Igonin magmatic event (707‒732 Ma) in the Tirlyan Syncline. The smallest ε_Nd(<i>t</i>) values (–3.2, –0.9, –0.7) indicating a decrease in the amount of a crustal component relative to the mantle material are determined for the Paleozoic metabasalts in the Tirlyan Syncline in the eastern wing of the Bashkirian Meganticlinorium, which is probably related to the activation of plume processes in the eastern part of the orogen. The Rb‒Sr and ¹⁴⁷Sm‒¹⁴³Nd ID-TIMS isotopic systematics of the studied volcanic rocks expands our understanding of mantle–crustal interactions within three stratigraphic levels with Riphean magmatic events of the South Urals.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"11 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141524940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Combinatorial–Variational Approach to Solving Linear and Nonlinear Inverse Problems in Geophysics","authors":"I. E. Stepanova, I. I. Kolotov","doi":"10.1134/s1028334x24602499","DOIUrl":"https://doi.org/10.1134/s1028334x24602499","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The problem of interpreting heterogeneous and multiprecision geophysical data is considered from the point of view of combinatorics within the framework of the approximation approach. The discrete nature of information about physical fields and their sources imposes a number of limitations on the possibilities of adequate data interpretation. Combinatorial methods of discrete mathematics make it possible to describe accurately the criteria for selecting data to approximate the elements of anomalous potential fields, as well as for controlling the quality of the approximate solution of inverse problems, both linear and nonlinear.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"19 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geodynamic Settings of the Seafloor Relief Formation in the Madagascar Basin from Data of the 29th Cruise of R/V Akademik Nikolai Strakhov","authors":"S. Yu. Sokolov, K. O. Dobroliubova, N. N. Turko, E. A. Moroz, A. S. Abramova, A. O. Mazarovich","doi":"10.1134/s1028334x2460230x","DOIUrl":"https://doi.org/10.1134/s1028334x2460230x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The morphology of the seafloor of the Madagascar Basin from Mauritius Island to the Southwest Indian Ridge (SWIR) is represented by a ridge-echeloned relief of the spreading basement. The azimuth of the relief differs by ~90° for the basin north of the SWIR and its wedge-shaped sublatitudinal rift system, separated by an abyssal escarpment. A genetic definition of this seafloor relief shape is given. This shape is formed when the ancient basement breaks up and accretion of the crust orthogonal to the azimuth, which existed before the rupture, begins. The formation of a wedge in the eastern part of the SWIR began about 41 Ma ago and is manifested by higher (±1100 m) amplitudes of relief variations than at the basement before the rupture (±250 m). The change in morphology is also associated with the change in the spreading azimuth of the lithospheric block by about 24° north of the SWIR, which opened up a new space for accretion. The morphology of the relief in the wedge and beyond shows the relationship of its parameters with slowdown in the spreading rate by almost three times when the kinematics of the plates have changed. The high-amplitude ridge-echeloned relief in the ultraslow segment of the SWIR with signs of nontransform displacement is combined with the maxima and minima of Bouguer anomalies. According to the published data, serpentized peridotites and basalts are obtained in the localization of the anomalies. These rocks indicate the presence of detachments with the exposure of ultramafic rocks and minimal magmatic output. Bouguer anomalies along the regional profile perfectly reflect deep density inhomogeneties. For intraplate volcanic edifices, they have a much greater deconsolidation in the upper mantle than near the active interplate boundary of the SWIR. According to the seismic tomography data, the absence of a deep upwelling under the newly formed SWIR segment and the presence of a “cold” gap in the “hot” lenses of the mantle indicates the action of tangential forces in the lithosphere that are not associated with general mantle convection. The formation of the new orthogonal rift system with ultraslow rates is an adaptation to variations in the kinematics parameters of the adjacent lithospheric plates.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"59 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Postcollision Porphyry Mo Mineralization of Central Tien Shan: First Data on U–Pb Isotopic (LA-ICP-MS) Dating of Zircon from Rocks of the Molo-Sarychat Productive Pluton, East Kazakhstan","authors":"S. G. Soloviev, S. G. Kryazhev, D. V. Semenova, Ya. A. Kalinin, N. S. Bortnikov","doi":"10.1134/s1028334x24602311","DOIUrl":"https://doi.org/10.1134/s1028334x24602311","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>First data on the U–Pb isotopic (LA-ICP-MS) age of zircon from intrusive rocks of the Molo-Sarychat pluton, which is confined to a system of deep faults of the “V.A. Nikolaev line” in East Kyrgyzstan, are presented. The rocks of this pluton belong to high-K calc-alkaline and shoshonite series with spatially and genetically related intense Mo(‒W‒Cu‒Au) (mainly, porphyry Mo) mineralization. In addition to other Au, W, and Cu deposits and occurrences, this mineralization is part of an extended metallogenic belt of Tien Shan; however, the occurrences of porphyry Mo mineralization are few in number in this belt. The concordant U–Pb isotopic age of zircon autocrysts indicates the crystallization of quartz monzonites and monzogranites in the Early Permian: 293.3 ± 4.2 and 286.6 ± 2.4 Ma, respectively. The age of zircon antecrysts is 306‒320 Ma. The age of crystallization corresponds to the postcollision evolutionary stage of this territory, whereas the presence of antecrysts expands the period of the origination of the pluton in the Late Carboniferous–Early Permian, thus spanning the tectonic settings first of subduction and then of postcollision regimes. We therefore identified the postcollision nature of Mo(‒W‒Cu‒Au) (porphyry Mo) mineralization, which is related to the studied pluton and formed after the intrusion of quartz monzonites and monzonites (early and late-stage mineralization, respectively). A significant enrichment in Mo can be related to its progressive accumulation during magmatic differentiation, which led to the intrusion of quartz monzonites and, especially, monzogranites. These processes occurred under a more mature postcollision tectonic regime with the possible formation of intermediate magmatic sources in the Early Proterozoic substrate of metamorphic rocks and ancient granitoids. The age values of rocks of the Molo-Sarychat pluton are similar to those identified for metasomatic and igneous rocks of the large Kumtor Au deposit also confined to the “V.A. Nikolaev line.”</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"60 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141507780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Granitoid Magmatism of the Joint Area between the Severnyi and Glavnyi Batholith Belts of the Verkhoyan–Kolyma Fold Area","authors":"M. V. Luchitskaya, M. V. Gertseva, S. D. Sokolov, I. V. Sysoyev","doi":"10.1134/s1028334x24602645","DOIUrl":"https://doi.org/10.1134/s1028334x24602645","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>New U–Th–Pb (SIMS)–geochronological, petro-geochemical, and Sr–Nd isotopic data for granitoids of three plutonic complexes (Sakhani, Omchikanda, and Arga–Emneken), located in the joint area of the two large batholih belts of the Verkhoyan–Kolyma fold area, Glavnyi and Severnyi, are presented. The Valanginian–Hauterivian age of the granitoids of all three complexes is established. The similarity of the granites and leucogranites of the Omchikanda and Sakhani complexes to the I–S-type granites and the similarity of the Arga–Emneken granitoids to the I-type granites are shown. The petro-geochemical peculiarities of the granitoid composition indicate a metasedimentary source for the granites and leucogranites of the Omchikanda and Sakhani complexes and a metamagmatic (amphibolitic) source for granitoids of the Arga–Emneken Complex. Sr–Nd isotopic data show that the granitoids were melted from different crustal sources, in which there are various proportions of mature material of the continental crust. The totality of geological and newly obtained geochronological, petro-geochemical, and isotopic data allow us to suppose a collisional setting of their formation in the terminal Valanginian–Hauterivian stage of collision between the Kolyma–Omolon microcontinent and the Siberian continent.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":"31 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}