陆态网络重力测网的分形特征与地震监测能力分析

Fractal Characteristics and Earthquake Monitoring Capability of the CMONOC Gravity Network

摘要:

介绍了“中国大陆构造环境监测网络”（简称“陆态网络”）重力观测体系。从分形几何学角度研究了陆态网络重力测网的分形特征，计算得到测网分维数D_f=1.5598、最佳网格化间距r=139km。综合测网分维数与重力时变距、重力异常范围、测网范围等量化指标，对陆态网络重力测网的地震监测能力进行分析，结果表明，测网最佳网格化间距等特征值与M_S6.0地震引发的重力场变化区域的特征异常区半径等统计量化指标接近，具备监测我国除边界及藏北无人区以外大陆区域的M_S6.0及以上地震的能力。

Abstract:

In this article we introduced the gravity observation system of Crustal Movement Observation Network of China(CMONOC). We studied the fractal characteristics of CMONOC gravity network from the perspective of fractal geometry,and calculated the fractal dimension of gravity network as D_f=1.5598,with the optimal grid spacing r=139km. We made a comprehensive analysis on the fractal dimension,gravity time-varying distance,gravity anomaly range,and the survey network range in order to estimate the capability of earthquake monitoring of the CMONOC. The results show that the optimal grid spacing of the survey network is close to the radius of the characteristic anomaly area of the gravity field change area caused by the M_S6.0 earthquakes,and the CMONOC gravity network is capable of monitor earthquakes above M_S6.0 in continental China except for the regions at the border and no civilization area in northern Tibet.