Crustal thickness and Poisson’s ratio beneath Zhangjiakou-Bohai seismic active belt and its neighboring regions
Zhang Yingying
Gao Yuan
Shi Yutao
Kelly Liu
Abstract：Based on the teleseismic events recorded by seismic stations of Shan-dong,Hebei,Liaoning,Beijing,Tianjin regional seismograph networks,this paper investigates the crustal thickness and average Poisson’s ratios beneath the stations by means of H-k receiver function stacking method.The results show that the crustal thickness in the studied region varies from 30 km to 46 km,and is thinning gradually from mountain to basin,suggesting a good correlation with surface terrain.On the other hand,distribution of the Poisson’s ratio overthe studied region is characterized by an obvious region segmentation.The low Poisson’s ratios beneath the east part of Yanshan might relate to the delaminationof North China craton.The region beneath east part of Tancheng-Luj iangfault zone exhibits a complex distribution of low Poisson’s ratios mixed withhigh ones,which might be related to volcanic activity.The convergence zone ofthe western segment of Zhangj iakou-Bohai seismic active belt and the lift exhibitsa little higher Poisson’s ratios,which might be caused by both broken rocksand the partial fusion of rocks near the seismic active belt. The station Beihuangcheng located on the island chain in the Bohai Sea shows a thick crustalthickness and a low Poisson’s ratio,but the reason behind the phenomenonwaits for further investigation.
Keywords：Zhangjiakou-Bohai seismic active beltTancheng-Lujiang fault zoneeastern part of North China cratoncrustal thicknessPoisson’s ratiore-ceiver function
Publication Date：2015-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：13( 541-553 )