环南极区域古水深演化初探

重构南极区域的古水深和历史地质格局，首先需要对研究区域进行板块重构，即在特定的时间点将洋壳和陆壳恢复到他们原来的地理位置上。本文采用Greiner阐述的欧拉旋转法进行板块重构。欧拉极参数主要参考Muller等基于大西洋-印度洋热点参考系的有限欧拉极，并将部分参数进行了必要的转换和统一。对于指定的重构年代，地壳年龄比重建年代年轻的区域需被移除。本文借助于Matlab等编程工具，恢复了南极及周边区域自130 Ma以来15个特定时间段的位置。综合多种数据，将现代水深根据热驱动地壳沉降、沉积作用和均衡作用的影响进行调整，对30°S以南区域的古水深进行重构，绘制了研究区域不同年代的古水深图，分析了南大洋自130 Ma以来的形成演化过程。

A PRELIMINARY STUDY ON THE EVOLUTION OF CIRCUM-ANTARCTIC PALEOBATHYMETRY

Reconstructing paleobathymetry around Antarctic first involves palinspastic reconstructions, which restore seafloor features and landmasses to their original geographic positions at a given point in time. In this paper we reconstruct the plate by using the Euler rotation method described by Greiner. And the Euler poles mainly refer to the finite poles based on the Atlantic-India ocean hotpots reference frame provided by Muller. Some parameters have been converted necessarily. Regions where oceanic crust is younger than the target age must be removed. We reconstruct 15 positions of the plates in and surround the Antarctica areas since 130 Ma using Matlab programming tools. Combing diverse data, we adjust the present-day bathymetry for the effects of thermally driven crustal subsidence, sedimentation, and isostatic rebound, and reconstruct the paleobathmatery south of 30°S. The paleobathmetry maps of different times have been made, and the evolution of Southern Ocean since 130 Ma has been analyzed briefly.