Regional Structure of the Antarctic Peninsula Derived from ERS-1 SAR Mosaic: A Study of Upper/Lower Plate Interactions During Subduction of the Antarctic/Aluk Ridge Crest

该合同支持使用欧洲ERS-1卫星合成孔径雷达（SAR）数据对南极半岛进行结构分析的项目。该项目展示了在大部分冰雪覆盖地区使用SAR数据进行地质和地球物理调查。南极半岛的新生代构造演化包括一个几何上简单的正交板块俯冲史，以及沿辐合缘由南至北的南极-阿鲁克脊脊断裂带边界段的连续碰撞。在南极半岛的地质和构造分割中反映了俯冲断裂带，因此，在俯冲边缘上，上下板块之间存在直接的力学相互作用。整个南极半岛的综合ERS-1 SAR拼接图的构造作图应该记录下任何断裂带进入大陆地壳的区域连续性，以及半岛内部可能与这些断裂带联系在一起的任何系统结构变化。目的是系统地评价沿会聚缘俯冲断裂带对上板块的影响。南极半岛为这样的研究提供了一个无与伦比的机会，因为海底记录有很好的记录，高质量的地质填图和野外构造数据中存在Oground truthO，并且汇聚边缘代表了断裂带/海沟相互作用最不复杂的情况。研究结果可为世界范围内构造更为复杂的收敛边缘构造提供参考。此外，这种使用ERS-1 SAR拼接的方法将作为基于SAR的冰覆盖地形结构测绘的原型，当RADARSAT数据可用时，应该证明是有用的。

Abstract This award supports a project to use synthetic aperture radar (SAR) data from the European ERS-1 satellite for a structural analysis of the Antarctic Peninsula. This project constitutes a demonstration of the use of SAR data for geological and geophysical investigations in largely ice covered regions. The Cenozoic tectonic evolution of the Antarctic Peninsula involves a history of geometrically simple orthogonal plate subduction, with successive collision of fracture zone-bounded segments of the Antarctic-Aluk ridge crest from south to north along the convergent margin. It has been proposed that the subducted fracture zones are reflected in geological and structural segmentation of the Antarctic Peninsula and, therefore, a direct mechanical interaction between the upper and lower plates along the subducting margin is suggested. Structural mapping from a synoptic ERS-1 SAR mosaic of the entire Antarctic Peninsula should document the regional continuity of any fracture zones into the continental crust and any systematic changes in structure within the peninsula that may be linked these fracture zones. The goal is to systematically evaluate the impact of subducting fracture zones on the upper plate along the convergent margin. The Antarctic Peninsula provides an unrivaled opportunity for such a study because the ocean floor record is well documented, Oground truthO exists from high-quality geologic mapping and field structural data, and the convergent margin represents the least complex scenario of fracture zone/trench interaction. The results of this study can provide a model for other convergent margins worldwide where the tectonics are more complicated. Furthermore, this approach, using an ERS-1 SAR mosaic, will serve as a prototype for SAR-based structural mapping in ice-covered terrain that should prove useful when RADARSAT data becomes available.