The Geology of the World Ocean (Arctic and Antarctic): Achievements and New Research

The Gramberg All-Russia Research Institute for Geology and Mineral Resources of the World Ocean (FSBI VNIIOkeangeologia) carries out a wide range of research in the fields of geology, engineering geology, geophysics, and geochemistry. The specialists of the institute perform studies using most-up-to-date equipment in several directions, including the study of the geology and mineral resources of the Arctic, Antarctic and the World Ocean. The geological and tectonic maps and atlases of the Eurasian sector of the Arctic shelf and adjacent deepwater zones of the Arctic Ocean have been compiled. This allow one to recognize the rift-related basins on the East Arctic shelf of Russia, and the conjunction areas of the Lomonosov, Gakkel, and Mendeleev oceanic ridges with the Eurasian continental margin. A comprehensive interpretation of geological and geophysical data has revealed features of the tectonics of the Amerasian Basin, which indicate that the evolution of the basin structures took place under conditions of continental rifting. One of the main scientific conclusions drawn at the preparation of the Submission of the Russian Federation in respect of the continental shelf boundary in the Arctic Ocean is the proof of the continental nature of the structures of the Central Arctic Rise Complex: the Lomonosov Ridge, Podvodnikov Basin, Alpha-Mendeleev Rise, Chukchi Basin, and Chukchi Borderland. This conclusion is confirmed by the characteristics of the main layers of the Earth's crust in the above structures. A geodynamic model of the evolution of the Precambrian complexes of East Antarctica has been developed and the main tectonic provinces of Antarctica have been distinguished. A universal seismostratigraphic model of sedimentary basins has been developed for the marginal seas of East Antarctica. An important area of research in Antarctica was the study of the subglacial Lake Vostok. When studying the history of the formation of sulfide mineralization, it was found that the discharge of hydrothermal ore-bearing solutions most often occurs continuously, and only the intensity of the ore formation process changes with time. The possibility of formation of massive sulfide ore volumes additional to the main surface deposit due to metasomatic replacement of host igneous rocks has also been established.