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V. I. Grebenshchikova M. I. Kuzmin O. A. Proydakova O. V. Zarubina 《Doklady Earth Sciences》2018,480(2):735-740
The long-term data (1950–2017) on the chemical composition of the water from the source of the Angara River, which is the only run-off from Lake Baikal, a large and clean fresh water reservoir, are presented. The absence of water contamination despite the anthropogenic influence is shown. The similarity and constancy of the current composition of the waters in the lake and the Angara River are recorded. It is recommended to continue geochemical studies of this unique world heritage site. 相似文献
994.
V. V. Avdonin N. I. Eremin E. A. Zhegallo N. E. Segreeva 《Doklady Earth Sciences》2018,481(1):839-841
As exemplified by cobalt–bearing Fe–Mn crusts (ferromanganese stromatolite) of the Magellan Seamounts (Clarion–Clipperton Province), the main stages of the structural evolution of bacterial communities have been recognized. It has been demonstrated that the change of the stages is caused by the effect of major tectonic, volcanic, and other geological events. 相似文献
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Golionko B. G. Basilyan A. E. Nikolsky P. A. Kostyleva V. V. Malyshev N. A. Verzhbitsky V. E. Obmetko V. V. Borodulin A. A. 《Geotectonics》2019,53(6):675-699
Geotectonics - Detailed lithological, stratigraphic, and structural studies of the fold-thrust structures were conducted on New Siberia Island. We have established that the jointly deformed... 相似文献
996.
V. B. Kurnosov B. A. Sakharov A. R. Geptner Yu. I. Konovalov E. O. Goncharov 《Lithology and Mineral Resources》2020,55(2):152-163
Clay minerals in basalt sills from the northern East Pacific Rise, covered by Upper Pleistocene clayey–sandy–silty sediments (turbidites, hemipelagites, and diatom oozes) sampled from DSDP Holes 477, 478, and 481A, were studied by X-ray methods based on the modeling of diffraction patterns. Trioctahedral smectites formed in thin (0.1–0.5 and 1.8–4 m) fissured sills that are well permeable for water delivered from the water-saturated host sediments heated by the sills. Smectites in basalts are found in the interstices (20–40 vol % in the rock and up to 50–80 vol % in hyalobasalts). They replace olivine and fill cracks and vesicles. Plagioclase and clinopyroxene are generally unaltered. The structure of smectites is characterized by different height of layers depending on the composition of cations in the interlayers and the degree of their hydration. The different-height layers either make up individual smectite phases or alternate in different proportions and with a high degree of segregation in the mixed-layer structures. Under conditions of a prolonged cooling, thick (43 m) sills are distinguished from the thin varieties by the formation of trioctahedral minerals (smectite–chlorite, chlorite, defective chlorite, and talc). They are found mainly in the interstices that make up 3–7 vol % of the rock. 相似文献
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