秦岭造山带及邻区双差层析成像

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关键词双差层析成像；秦岭造山带；汉中盆地；地壳速度结构中图分类号：P315.2 文献标识码：A 文章编号：2096-7780（2025）05-0249-10doi：10.19987/j.dzkxjz.2024-163

AbstractThe Qinling orogenic belt and its adjacent areas serve as the convergence zone between the North China craton，the Yangtze craton，andthe northeastern edge ofthe Qinghai-Xizang Plateau are characterized bycomplex tectonic activity.This studyutilizes observational data from 159 fixed stations ofthe ChinaEarthquake Administration in Shaanxi， Sichuan，Gansu，andotherregions，as wellas182broadband mobile stations from the ChinArrayI project.Weobtained athre-dimensional velocitystructureof the Qinling orogenicbeltand itsadjacent areas byemploying the doubledifferencetomography method.Theimaging resultsreveal that the crustal thicknessof the Hanzhong basin is approximately 38km ，and the Moho interface exhibits a dome-like shape， convex in the center and concave on both sides. Additionally，a significant low-velocity anomaly is observed along the northern edgeof the western Qinling orogenic belt and the southern side of the Longxian-Baoji fault zone， extending to a depth of approximately 39km This anomaly is associated with the eastward flow of materials from the middle and lower crust of the Qinghai-Xizang Plateau.

Keywordsdouble-difference tomography; Qinling orogenic belt; Hanzhong basin; crustal velocity structure

0 引言

秦岭造山带位于青藏高原、华北块体、扬子块体交汇地带，同时与大巴山造山带、摩天岭地块相交汇。（剩余14452字）