Intracontinental deformation, paleo-stress field and tectonic setting in northeastern Alxa Block since Late Mesozoic

Intracontinental deformation and its tectonic setting is one of the hot topics of geological research. As the Langshan area in northeastern Alxa Block experienced multistage intracontinental deformations since Late Mesozoic, it is an ideal representative region to study intracontinental deformation. Based on large-scale structural mapping, detailed geological survey to clarify field cutting relationship, combined with published zircon geochronology and low-temperature thermochronology results, six stages of intracontinental deformation since the Late Jurassic in Langshan area have been determined.The vector data inversion of fault planes indicates that the deformations in different periods were formed in different paleo-stress fields. Both the previous structures and continuous accretion to the Eurasian continental margin from different directions control the tectonic evolution of Langshan area since Late Jurassic.From Late Jurassic to Late Cretaceous, the tectonic deformations of the Langshan area were mainly affected by the Paleo-Pacific tectonic domain, whereas, in Cenozoic, it began to be affected by the tectonic evolution of the Qinghai-Tibet Plateau.