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51.
A. A. Velichko O. K. Borisova Yu. M. Kononov E. A. Konstantinov R. N. Kurbanov T. D. Morozova P. G. Panin V. V. Semenov A. S. Tesakov S. N. Timireva V. V. Titov P. D. Frolov 《Doklady Earth Sciences》2017,475(2):895-899
An integrated study of the loess–soil sequence in the coastal exposure near the settlement of Beglitsa (Rostov oblast) allowed us, for the first time, to reconstruct the landscape-climatic changes that occurred in the eastern Azov region over the course of the Late Pleistocene. In the south of the periglacial zone, considerable differences between intensity of the loess accumulation in the Early and Late Valdai Cryochrons were revealed. In the Early Valdai Epoch, which corresponds roughly to the end of Marine Isotope Stage (MIS) 5 and MIS 4, loess accumulation occurred after completion of development of the Mezin pedocomplex and before the beginning of the Bryansk stage of soil development, i.e., over more than 20 000 years. In the much shorter Late Valdai Cryochron MIS 2 (10 000–12 000 years), loess accumulation reached 5 m. The data evaluation shows that the loess accumulation rates in the Early Valdai Epoch (~0.07 mm/year) and the Late Valdai Epoch (~0.5 mm/year) differ from each other by an order of magnitude. 相似文献
52.
Cretaceous and Jurassic intrusions in Crimean Mountains: The first data of U–Pb (SIMS SHRIMP) dating
U–Pb geochronological studies of igneous rocks of the Crimean Mountains were carried out for the first time. The ages of magma crystallization determined for gabbro–dolerites of the Dzhidair and Pervomaiskii intrusions point to the injection of these rocks during the Middle Jurassic Aalenian–Bajocian stage of magmatism. The Berriasian–Valanginian and Aptian age of sill-like bodies within the mass of volcanogenic–sedimentary rocks presumes the necessity to reconsider the common notion of an exclusively Albian magmatic event during the Cretaceous. High-precision U–Pb dating of magma intrusions allowed us to verify the age of Middle Jurassic magmatism and to distinguish the new Early Cretaceous Berriasian–Valanginian magmatism stage of basic composition. 相似文献
53.
Hagen-Thorn V. A. Morozova D. A. Savchenko S. S. Hagen-Thorn E. I. Milanova Yu. V. Shalyapina L. V. Vasil’ev A. A. 《Astronomy Reports》2021,65(12):1233-1245
Astronomy Reports - We present and analyze the monitoring results of the blazar 1156+295 in radio, optical, and gamma ranges in 2005–2020. After a long period of relative quietness at the end... 相似文献