地质学报2024，Vol.98Issue(1)：1-15,15.DOI:10.19762/j.cnki.dizhixuebao.2023137
深反射地震成像揭示的班公湖-怒江缝合带中段Moho断阶及其大地构造意义
Moho terraces and its tectonic significance of central Bangong-Nujiang suture zone uncovered by deep-reflection seismic imaging
摘要
Abstract
Knowledge of the Moho in the Bangong-Nujiang suture(BNS)is geodynamically of importance to understand the subduction of Meso-Tethys oceanic crust and the genesis of southern Qiangtang depression.Based on deep-reflection seismic data(88°30′E)across the BNS,depth-domain seismic profile and velocity field with high-resolution Moho geometry are obtained by deep-reflection seismic imaging using such techniques as mid/long wavelength static correction,noise elimination,optimal stacking,and PSDM.The depth-domain imaging shows that the Moho of the BNS located at a depth of 65～80 km tends to discontinuously uplift northwards,indicating a few lithospheric mantle terraces(up to 15 km)developed between the Lhasa and Qiangtang terranes.The geometry of the Moho in the BNS demonstrates that the terraces have been driven by southern lithospheric mantle subduction at 19.5° northward and northern crustal uplifting of southern Qiangtang basin due to possible deep partial melting.The Moho structure suggests that southern Qiangtang basin was evolved from marginal marine into foreland basin during the Late Jurassic to the Early Cretaceous along with the Meso-Tethys closure.关键词
深反射地震成像/叠前深度偏移/班公湖-怒江缝合带/Moho界面/南羌塘坳陷Key words
deep-reflection seismic imaging/prestack depth migration/Bangong-Nujiang suture/Moho/South Qiangtang depression引用本文复制引用
程建,刘志伟,赵文津,史大年,田涛,邓世广,张克强,张若渔..深反射地震成像揭示的班公湖-怒江缝合带中段Moho断阶及其大地构造意义[J].地质学报,2024,98(1):1-15,15.基金项目
本文为中国石化科技部项目(编号33550007-20-ZC0613-0088)、中国地质科学院基本科研业务费项目(编号JKY21024)和中国地质调查项目(编号DD20211343、DD20221855)联合资助的成果. （编号33550007-20-ZC0613-0088）
