Abstract
Most previous studies advocate that crustal weakening in the Yunnan area is predominantly the result of eastward growth of the Tibetan Plateau. Here we observe regional variations in the Yunnan crustal structure from the waveform characteristic variations of receiver functions at 342 seismic stations. Furthermore, receiver function imaging along three seismic sections reveals the response of crustal structure to different tectonic evolution. Our results show that northwestern Yunnan is characterized by 49–64 km-thick crust with multi-layer low-velocity materials and local lower crustal “doublet”. These low-velocity structures may reflect partial melting caused by crustal thickening associated with the eastward growth of the plateau. However, in southern and eastern parts of Yunnan, the topography of the Moho varies relatively gently with crustal thicknesses of 26–42 km, and widespread low-velocity zones are located above the crust-mantle boundary. We speculate that these features might favor the action of partial melting of crust triggered by asthenospheric upwelling related to the subduction of the India plate.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
