基于密集GNSS的华北地区现今地壳垂直形变特征  

Present-day crustal vertical deformation characteristics of North China from dense GNSS observations

作　　者：李奇 普运伟 王岩[3] 刘昱岑[1] Li Qi;Pu Yunwei;Wang Yan;Liu Yucen(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming 650093,China;Computer Center,Kunming University of Science and Technology,Kunming 650500,China;Yunnan Earthquake Agency,Kunming 650224,China)

机构地区：[1]昆明理工大学国土资源工程学院,昆明650093 [2]昆明理工大学计算机中心,昆明650500 [3]云南省地震局,昆明650224

出　　处：《地震学报》2025年第2期169-181,共13页Acta Seismologica Sinica

摘　　要：华北地区作为内陆典型的伸展断陷区和强震活动区,在东部太平洋俯冲和西部印度大陆碰撞的双重构造作用和地下水过量开采的背景下,其垂直形变特征表现为明显的区域差异。为定量分析华北地区现今的地壳垂直形变特征,对收集整理的1406个GNSS站点1999—2019年长达二十年的GPS观测资料进行统一的高精度处理,获取了该地区高空间分辨率的垂向形变速度场。结果显示:华北平原、淮河平原和大别山以南区域以沉降为主,其中华北平原和淮河平原的最大沉降速率分别约为70 mm/a和50 mm/a;太行山、吕梁山、苏鲁造山带、燕山表现为隆升,隆升速率为0.1—4 mm/a;部分GNSS土层站点在山西裂谷和太行山地区的垂向形变表现为沉降,而GNSS基岩站表现为隆升,说明该地区的沉降现象可能是地下水过量开采所致,并非构造运动而引起。The North China region,which is characterized as a typical intracontinental extensional rift zone and an area with strong seismic activity,exhibits notable regional differences in vertical deformation patterns.These disparities are attributed to the combined tectonic effects of the subduction of the Pacific Plate to the east and the collision of the Indian Plate to the west,along with excessive groundwater extraction.To quantitatively analyze the vertical deformation characteristics of this region,we collected 1406 GPS observation datasets covering a twenty-year period from 1999 to 2019,and then processed the data by using a unified high-precision processing method.As a result,we acquired a vertical deformation velocity field with high spatial resolution.The results reveal distinct deformation patterns across different geological units:The North China plain and Huaihe plain mainly experience subsidence,with maximum subsidence rates of approximately 70 mm/a and 50 mm/a,respectively.In contrast,the Taihangshan,Lüliangshan,Sulu orogenic belt,and Yanshan exhibit uplift patterns with rates ranging from 0.1 mm/a to 4 mm/a.Notably,the vertical deformation patterns from GNSS stations in the Shanxi rift zone and Taihangshan areas present an intriguing dichotomy.We also noticed that,some GNSS stations on soil show subsidence,while those on bedrock show uplift,suggesting that the observed subsidence is likely attributable to excessive groundwater extraction rather than tectonic movements.This study is the first to integrate meteorological GNSS observation data into vertical deformation research,significantly improving the spatial resolution of vertical deformation velocity fields in the North China Craton.The most pronounced subsidence appears in North China plain,forming a NE-SW trending subsidence belt that coincides with fault orientations.However,due to the lack of GNSS bedrock stations in these areas,accurately quantifying the respective contributions of tectonic and non-tectonic to the observed vertical deformation r

关 键 词：华北 GNSS 垂直形变 构造运动 

分 类 号：P315.725[天文地球—地震学]