파푸아 뉴기니 Bismarck해의 판구조 경계면에서의 다양한 판구조 및 마그마 환경

Abstract

The backarc spreading in the Bismarck Sea Occurs along a complex set of divergent and transtensional boundaries. The plate boundary in the Bismarck Sea was first delineated by regional seismicity, Bismarck Sea Seismic Lineation(BSSL), which was later divided into discrete segments by Connelly(1974,1976) and Taylor(1975). Most of the past investigations have focused on the eastern side of Bismarck Sea, where numerous hydrothermal vent fields were discovered, including Vienna Woods, PACMANUS, DESMOS and SuSu Knolls. Major tectonic and magmatic events in the eastern Bismarck Sea occur along the Extensional Transform Zone(ETZ), Manus Spreading Center(MSC), Southern Rift(SR) and Southeasrern Rift(SER). On the other hand, the spreading system in the central region, especially along the Western Manus Rift(WMR), and transtensional system further to the west (west Bismarck transform fault, WBFT) have received little attention. This lecture provides a comprehensive view of the backarc spreading system in the Bismarck Sea by reviewing past studies and presenting new observational results, including those obtained PACMANUS hydrothermal vent field, which include deep-ocean drilling and near bottom magnetic observations.