Paleobathymetry and historical plate position are important reference factors for studying ancient currents, ancient climate, and historical geological events. Reconstructing paleobathymetry around Antarctica 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 using the Euler rotation method described by Greiner. The Euler poles refer mainly to the finite poles based on the Atlantic-Indian Ocean hotspots reference frame described by Miiller, but some parameters have been converted. Regions where the oceanic crust was younger than the target age had to be removed. We reconstruct 15 positions of the plates in and around Antarctica since 130 Ma. Combining diverse data including bathymetric parameters, crustal age, and sediment thickness, we adjust the present-day bathymetry for the effects of thermally driven crustal subsidence, sedimentation, and isostatic rebound, and reconstruct the paleobathymetry south of 30°S. We develop paleobathymetry maps for different times, and the evolution of the Southern Ocean since 130 Ma is briefly analyzed.%古水深及板块历史位置是研究古洋流、古气候和地质历史事件的重要参考因子.重构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当时的地理位置上.本文采用Greiner阐述的欧拉旋转法,在去除地壳年龄比重建年代年轻的区域的基础上,恢复了南极及周边区域自130 Ma以来15个特定时间点的位置.其旋转参数主要参考Müller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.然后综合现代水深、地壳年龄、沉积物厚度等数据,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,分析了其自130 Ma以来的形成演化过程.
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