ZHENG Guang-gao1,2, LIU Xiao-chun1, ZHAO Yue1
1. Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China;
2. School of Earth and Space Sciences, Peking University, Beijing 100871, China
Abstract: In order to understand the Mesozoic-Cenozoic tectonomagmatic evolution of the Antarctic Peninsula and its correlation with Patagonia of southernmost South America, this paper briefly overview the distribution, ages, petrogenesis and tectonic settings of magmatic rocks from the Antarctic Peninsula, and geological history of Patagonia. The Antarctic Peninsula region can be divided into three major tectonic domains:(1)the East Domain related to Gondwanaland,(2)the Central Domain composed by magmatic arc terrane, and(3)the West Domain that represents an accretion complex. The Paleozoic magmatic rocks only locally occurs in the East and Central Domains, while the Mesozoic-Cenozoic volcanic and intrusive rocks dominate the Central Domain. Moreover, the Mesozoic-Cenozoic magmatism gradually migrated with time from southeast to northwest in the Antarctic Peninsula and from southwest to northeast in the South Shetland Islands. During the Mesozoic and Cenozoic, the Antarctic Peninsula experienced multiple tectonic movements, including oceanic subduction and island-arc accretion before the Cretaceous convergence for all the three domains, the initial convergence and tectonic erosion among these domains in the Early Cretaceous, collisional orogeny in the mid-Cretaceous, the formation of the George VI Sound before ~50Ma, and the opening of the Bransfield Strait back-arc basin at ~4Ma. The geological comparison between the Antarctic Peninsula and Patagonia suggests that the two regions were connected at least before Cretaceous.
Keywords: Arc magmatism Mesozoic-Cenozoic Antarctic Peninsula Patagonia
E-Mail: tiangang755@163.com
Bulletin of Mineralogy, Petrology and Geochemistry Vol.34, No.6, 2015, page 1090-1102
