摘要
以1999~2007年GNSS观测资料为基础,利用多核函数及应变场的无偏算法,在形变场连续变化的条件下获得了华北地区现今形变场的非线性空间变化结果,局部区域超8mm/a,其他部位隆升一般在6mm/a以内;华北平原存在着一个巨型沉降"漏斗",漏斗中心的数值近60mm/a。就构造活动而言,结果基本揭示了华北地区现今的形变特征。
Based on the GNSS observations(1999-2007),employing the filter and resolution of multi-kernel functions and the unbiased algorithm of strain field,under the condition of continuously changing deformation field,this paper obtains the nonlinear spatial variations of current deformation field of North China.It shows: ①Under the regional No-Net_Rotation frame,the horizontal movement was generally within 3 mm/a,the East-West movements are dominantly compressive,while the North-South movements are dominantly tensive.But these are not well-distributed.②The tension and compression distributions of the East-West strain are zonal in EW directions,and wavy in EW direction;these distributions of the North-South strain are alternate and annular;the absolute values of the North-South strain are within 27×10^-9 rad/a,while the North-South strain values are smaller than East-West strain's generally.③The surface strain shares the same distribution characteristics with East-West strain,and its absolute values are within 30×10^-9 rad/a.④The horizontal rotation mode shows that the North China rotates mainly clockwise,obviously the north section of west Ordos block and the south section of Shanxi fault depression.The values are within 12×10-9 rad/a.But the internal differential changes are obvious,such as Beijing-Tianjin area in the east of Yanshan zone,has significant anticlockwise rotations,and its maximum value reaches 10×10^-9 rad/a.⑤The vertical movements show an inherited characteristics in general.The maximum uplift is in Taihang mountains and the rates reach 8mm/a in some area.In North China plain there is a huge subsidence funnel whose center has a subsidence rate of 60mm/a.On the tectonic activities,the results have revealed the current deformation characteristics of North China essentially.
出处
《武汉大学学报(信息科学版)》
EI
CSCD
北大核心
2013年第1期31-35,128-130,共5页
Geomatics and Information Science of Wuhan University
基金
国家科技支撑计划资助项目(2012BAK19B01-2)
中国地震局"强化华北地区强震监视跟踪"专项资助项目
关键词
GNSS
华北地区
三维形变
趋势特征
GNSS
North China
three-dimensional deformation
trend characteristic