[Objective]Ophiolites,as fragments of ancient oceanic lithosphere,serve as a natural laboratory for studying the evolution of the lithospheric mantle,material cycling in subduction zones,and reconstructing paleogeographic patterns.The China-Mongolia border region is located within the Central Asian Orogenic Belt(CAOB),where ophiolite(mélange)belts intermittently crop out along both sides of the boundary,exhibiting blocky and zonal distributions.[Methods]To further clarify the tectonic evolution of the Central Asian Orogenic Belt and restore its structural framework,this paper relies on the results of the China-Mongolia collaborative 1/1 000 000 geological map series compilation project,combined with previous studies on the ophiolite(mélange)belts in this region.[Results]Fourteen ophiolite(mélange)belts were identified in the study area.A comprehensive explanation of their spatial-temporal distribution characteristics was provided,and a spatial-temporal framework for the distribution of the ophiolite(mélange)belts was established.[Conclusions]The results indicate that the ophiolite belts along the China-Mongolia border exhibit a trend of progressively younger ages from west to east(Neoproterozoic to Early Permian).This reveals differences in the evolution of the oceanic lithospheric mantle between the western and eastern segments of the Central Asian Orogenic Belt.Most ophiolite(mélange)belts are of the SSZ(supra-subduction zone)type,closely related to subduction processes.However,the tectonic settings of fore-arc and back-arc environments remain controversial and require further study.
关键词
中蒙边界/中亚造山带/蛇绿岩/时空分布/构造演化
Key words
China-Mongolia border/Central Asian Orogenic Belt/ophiolite/spatiotemporal distribution/tectonic evolution
维普
万方数据