南极构造学：ERS-1卫星海洋重力场的约束条件

Antarctic Tectonics: Constraints From an ERS-1 Satellite Marine Gravity Field.

作者信息

McAdoo D, Laxon S

机构信息

D. McAdoo is with the Geosciences Laboratory, National Ocean Service, National Oceanic and Atmospheric Administration, Silver Spring, MD 20910, USA. S. Laxon is with Mullard Space Science Laboratory, Department of Space and Climate Physics, University College London, Dorking, Surrey RH5 6NT, UK.

出版信息

Science. 1997 Apr 25;276(5312):556-61. doi: 10.1126/science.276.5312.556.

DOI:10.1126/science.276.5312.556

PMID:9110969

Abstract

A high-resolution gravity field of poorly charted and ice-covered ocean near West Antarctica, from the Ross Sea east to the Weddell Sea, has been derived with the use of satellite altimetry, including ERS-1 geodetic phase, wave-form data. This gravity field reveals regional tectonic fabric, such as gravity lineations, which are the expression of fracture zones left by early (65 to 83 million years ago) Pacific-Antarctic sea-floor spreading that separated the Campbell Plateau and New Zealand continent from West Antarctica. These lineations constrain plate motion history and confirm the hypothesis that Antarctica behaved as two distinct plates, separated from each other by an extensional Bellingshausen plate boundary active in the Amundsen Sea before about 61 million years ago.

摘要

利用卫星测高数据，包括ERS-1大地测量相位、波形数据，获得了西南极洲附近测绘程度低且被冰覆盖的海洋（从罗斯海东部到威德尔海）的高分辨率重力场。该重力场揭示了区域构造结构，如重力线理，它们是早期（6500万至8300万年前）太平洋-南极海底扩张留下的断裂带的表现，那次扩张将坎贝尔高原和新西兰大陆与西南极洲分开。这些线理限制了板块运动历史，并证实了以下假说：南极洲曾作为两个不同的板块，在约6100万年前之前，被阿蒙森海活跃的伸展性别林斯高晋板块边界分隔开来。