海洋地质前沿2026，Vol.42Issue(9)：33-43,11.DOI:10.16028/j.1009-2722.2025.194
东南印度洋西北段洋盆两翼地壳厚度差异及其成因
Differences in crustal thickness and cause between the two flanks of the oceanic basin in the northwestern segment of the Southeast Indian Ocean
摘要
Abstract
The northwestern segment of the Southeast Indian Ocean exhibits a complex tectonic setting,charac-terized by asymmetric spreading rates between its two flanks,a remnant subducting slab beneath the southern flank,and mantle plumes to the east.These factors may collectively influence oceanic crustal thickness.To char-acterize the crustal thickness distribution and investigate the long-term accretion mechanisms in this region,this study focuses on the area between 75°E and 80°E with crustal ages younger than 30 Ma.By integrating gravity in-version and plate reconstruction models,we calculated the age-averaged crustal thickness(AACT)of the oceanic basins on both flanks of the ridge,thereby delineating the spatial variation in crustal thickness.Results reveal a distinct asymmetry in crustal thickness between the two flanks:the northern flank has an average AACT of 6.4 km,being obviously thicker than the 6.0 km observed on the southern flank.Furthermore,both the crustal thickness difference and the half-spreading rate difference between the northern and southern flanks decrease from west to east,while the Curie point depth shows no corresponding systematic variation.Therefore,we concluded that the faster spreading rate of the southern flank is the primary factor leading to its thinner crust.关键词
东南印度洋/重力反演/地壳增生动力学/地壳厚度/洋中脊Key words
Southeast Indian Ocean/gravity inversion/crustal accretion dynamics/crustal thickness/mid-ocean ridge分类
海洋科学引用本文复制引用
宋新健,白永良,杜家乐,徐思然,董冬冬..东南印度洋西北段洋盆两翼地壳厚度差异及其成因[J].海洋地质前沿,2026,42(9):33-43,11.基金项目
国家自然科学基金(42476063,42176068) （42476063,42176068）
中石油重大科技专项(2023ZZ05) （2023ZZ05）
中央高校基本科研业务费专项(26CX0500XA) （26CX0500XA）
