测绘学报

• 学术论文 •    

考虑区域构造特征的地壳形变分析拟合推估模型

赵丽华1,杨元喜2,王庆良3   

  1. 1. 长安大学地质工程与测绘工程学院
    2. 中国卫星导航定位与应用管理中心
    3. 中国地震局第二监测中心
  • 收稿日期:2010-05-27 修回日期:2011-02-28 出版日期:2011-08-25 发布日期:2011-08-25
  • 通讯作者: 赵丽华

Collocation Model Based on Regional Tectonic Features in Crustal Deformation Analysis

  • Received:2010-05-27 Revised:2011-02-28 Online:2011-08-25 Published:2011-08-25

摘要: 将拟合推估方法应用于地壳形变分析不仅能获得变形趋势的最优估计,而且能较可靠地推估非观测点上的形变。但是该算法要求形变“信号”在空间是“连续”、“平稳”地变化,如果研究区域存在小断层或隐伏断层,则拟合推估法不能给出合理的结果。基于此,本文提出建立基于区域构造特征的形变分析拟合推估模型,即通过地质资料对可能存在断层的区域进行概略划分,对分布在断层附近的点建立各区域形变参数置信区间,通过检验判断相应点的归属;然后在差异运动边界已确定的各个区域分别建立拟合推估模型,计算区域形变场。针对区域内可能存在的明显的局部变形或观测异常的测站,提出用高崩溃污染率抗差估计法进行控制,以确保所建立形变分析模型能可靠描述研究区域的形变趋势。最后分别以一模拟算例和一实测算例验证了所提方法的有效性。

Abstract: Collocation method, when applied to crustal deformation analysis, can estimate the deformation trend reliably not only of the observed points but also of the unobserved points. But if there are faults or hidden faults in the researched area, accustomed collocation is not proper to deformation analysis because of the discontinuous deformation. So collocation based on regional tectonic deformation background is proposed, which divides the area roughly according to geology information and then establishes collocation models respectively in each division. The points near by the boundary are differentiated by confidence interval of deformation parameter. Since the local deformation or abnormal observations may influence the reliability of modeling, robust estimation with high breakdown point is applied to calculate model parameter which is not disturbed by abnormal points. Simulated and practical examples are given and the results prove the efficiency of the proposed method in this paper.