StudyofCurieisothermalsurfaceinSichuanBasinandtheseismicareaonitswesternmar┐gin  

作　　者：张先 虎喜凤 沈京秀 田长征 

出　　处：《Acta Seismologica Sinica(English Edition)》1996年第1期104-111,共8页

摘　　要：Using the aeromagnetic data and the method of 3-D magnetic stratum inversion, the data of aeromagnetic anomalies in the investigated region have been processed; and thereby the quantitative buried depth of the Curie isothermal surface in Sichuan Basin and its western marginal area has been obtained. The reliability of the inversion results has been confirmed by the features of regional tectonics, the distribution of geothermal gradient and the results of deep seismic sounding. By analyzing the deep geothermal field, it is concluded that the followings are the environmental conditions for the development and occurrence of earthquakes in the western marginal area of Sichuan Basin: (1) The collision of the Yangtze block with the Sichuan Qinghai block and Kangdian rhombic block has produced strong stress accumulation; and (2) Plastic creep in the middle lower crust owing to the upwelling of mantle flux has provided an adjusting unit for rock rupture and stress release.Using the aeromagnetic data and the method of 3-D magnetic stratum inversion, the data of aeromagnetic anomalies in the investigated region have been processed; and thereby the quantitative buried depth of the Curie isothermal surface in Sichuan Basin and its western marginal area has been obtained. The reliability of the inversion results has been confirmed by the features of regional tectonics, the distribution of geothermal gradient and the results of deep seismic sounding. By analyzing the deep geothermal field, it is concluded that the followings are the environmental conditions for the development and occurrence of earthquakes in the western marginal area of Sichuan Basin: (1) The collision of the Yangtze block with the Sichuan Qinghai block and Kangdian rhombic block has produced strong stress accumulation; and (2) Plastic creep in the middle lower crust owing to the upwelling of mantle flux has provided an adjusting unit for rock rupture and stress release.

关 键 词：aeromagnetic inversion Curie isothermal surface seismogenic. 

分 类 号：P318.5[天文地球—固体地球物理学]