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Information × Registration Number 0312U003109, 0111U008943 , R & D reports Title Models of the Earth's crust of Antarctic Peninsula continental margin. popup.stage_title Моделі земної кори континентальної окраїни Антарктичного півострова Head Bakhmutov Volodymyr, Registration Date 07-02-2012 Organization S.I.Subbotin Institute of geophysics HASU. popup.description2 We investigated the crust structure of the continental margin of the Antarctic Peninsula (AP), which is a composite block of the crust, and its western part - the magmatic arc of the Pacific margin of Gondwana. It was formed as a result of collisions allochtonous terrane with the margin of Gondwana and subsequent processes of subduction of the former Phoenix plate under the AP block. The last one today is passive, but the active tectonic events in the recent geological past are reflected in geophysical fields (potential and wave). The AP block is characterized by high amplitudes of gravity and magnetic anomalies, indicating the presence of mafic plutonic rocks which form a huge batholiths of AP. 2D gravity and magnetic modeling (with seismic data of the profiles DSS-13 and 8545-03) along the line which crossed the continental margin southern Avers island (near the UAS Academik Vernadsky) have been done. According to modeling results the margin crust of AP belongs to the continental type and includes two crystalline blocks (domains) that have been compounds during Late Jurassic time. East domain of Gondwana margin, occupying the AP mainland and inner shelf, has thick (~40 km), high-velocity/density continental crust. The transition unit has a thin (~ 26 km) crust, lower density and characterized by high-amplitude gravity anomalies along the shelf edge and on the outer shelf, which connection with accretion tectonics caused by subduction processes in Cretaceous. Our modeling shows that two belts of magnetic anomalies of the PMA (Pacific Margin Anomaly) belong to the different crustal domains: the western belt relates to transition (accretional) block, while the eastern belt corresponds to Gondwana margin block. This could be an evidence that the PMA, associated with an intense phase of tonalitic plutonism in Early Cretaceous, relate to tectono-magmatic event occurred after collision of Gondwana margin and transition domain (in Late Jurassic). Product Description popup.authors Єгорова Тамара Петрівна Бахмутов Володимир Георгійович Соловйов Валерій Дмитрович popup.nrat_date 2020-04-02 Close