﻿ 联合安徽CORS分析郯庐断裂带南段地壳形变与断层活动特征
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 大地测量与地球动力学  2022, Vol. 42 Issue (1): 65-70  DOI: 10.14075/j.jgg.2022.01.013

### 引用本文

CHEN Hao, TAO Tingye, LI Shuiping, et al. Analysis of Crustal Deformation and Fault Activity Characteristics in the Southern Segment of Tanlu Fault Zone with AHCORS[J]. Journal of Geodesy and Geodynamics, 2022, 42(1): 65-70.

### Foundation support

Natural Science Foundation of Anhui Province, No.1808085MD105.

### Corresponding author

TAO Tingye, PhD, associate professor, majors in GNSS algorithms and applications, lidar technology and applications, E-mail: czytty@163.com.

### 第一作者简介

CHEN Hao, postgraduate, majors in GNSS data processing and crustal deformation, E-mail: ch16229@126.com.

### 文章历史

1. 合肥工业大学土木与水利工程学院，合肥市屯溪路193号，230009

1 GNSS数据处理

 图 1 郯庐断裂带南段及周边区域水平运动速度场 Fig. 1 Horizontal velocity field on the southern of the Tanlu fault and its surrounding areas

2 联合AHCORS参考站的多尺度球面小波应变场解算 2.1 多尺度球面小波基本原理

 $\begin{array}{l} {\psi _{x, a}}X' = {\lambda _a}{\left( \gamma \right)^{\frac{1}{2}}}{\rm{exp}}\left[ { - \frac{{{{\tan }^2}\left( {\frac{\gamma }{2}} \right)}}{{{a^2}}}} \right] - \\ \;\;\;\;\;\;\;\frac{1}{a}{\lambda _{{\alpha ^a}}}{\left( \gamma \right)^{1/2}}{\rm{exp}}\left[ { - \frac{{{{\tan }^2}\left( {\frac{\gamma }{2}} \right)}}{{\alpha {a^2}}}} \right] \end{array}$ (1)

2.2 多尺度球面小波估计速度

 图 2 由AHCORS参考站分布确定的球面小波分解尺度 Fig. 2 Spherical wavelet decomposition scale based on AHCORS distribution

 $\nu \left( {\theta , \varphi } \right) = {\nu _\theta }\left( {\theta , \varphi } \right)\hat \theta + {\nu _\varphi }\left( {\theta , \varphi } \right)\hat \varphi$ (2)

 $\nu \left( {\theta , \varphi } \right) = \mathop \sum \limits_{k = 1}^n \left[ {{a_k}{g_k}\left( {\theta , \varphi } \right)\hat \theta + {b_k}{g_k}\left( {\theta , \varphi } \right)\hat \varphi } \right]$ (3)

 图 3 正则化参数 Fig. 3 Regularization parameter

 图 4 多尺度球面小波估计速度场与实际速度场的矢量对比 Fig. 4 Vector comparison of velocity field estimated by multi-scale spherical wavelet and actual velocity field

 图 5 多尺度球面小波估计速度场与实际速度场的标量对比 Fig. 5 Scalar comparison of velocity field estimated by multi-scale spherical wavelet and actual velocity field
2.3 应变场解算

 $\begin{array}{l} \;\;\;\;\;\;\;\;\;\;\;\;\;\;D = \left[ {\begin{array}{*{20}{c}} {{e_{\theta \theta }}}&{{e_{\theta \varphi }}}\\ {{e_{\theta \varphi }}}&{{e_{\varphi \varphi }}} \end{array}} \right] = \\ \left[ {\begin{array}{*{20}{c}} {\frac{1}{r}\cdot\frac{{\partial {u_\theta }}}{{\partial \theta }}}&{\frac{1}{{2r}}\left( {\frac{{\partial {u_\varphi }}}{{\partial \theta }} + \frac{1}{{\sin \theta }}\cdot\frac{{\partial {u_\theta }}}{{\partial \theta }} - {u_\varphi }\cot \theta } \right)}\\ {{D_{23}}}&{\frac{1}{r}\left( {\frac{1}{{\sin \theta }}\cdot\frac{{\partial {u_\varphi }}}{{\partial \varphi }} + {u_\theta }\cot \theta } \right)} \end{array}} \right] \end{array}$ (4)

3 郯庐断裂带南段地壳形变与断层活动分析 3.1 应变场分析

 图 6 基于多尺度球面小波解算的面膨胀率 Fig. 6 The dilatation rate of multiscale spherical wavelet solution

 图 7 qmax=8时的主应变率/面膨胀率和最大剪应变率 Fig. 7 Principal strain rate/ dilatation rate and maximum shear strain rate at qmax=8
3.2 速度剖面分析

 图 8 郯庐断裂带南段的3个速度剖面 Fig. 8 Three velocity profiles on the southern segment of the Tanlu fault

4 结语

1) 安徽地区在欧亚框架下主要朝东偏南方向运动。本文利用多尺度球面小波法模拟出的速度场与实际速度场的误差在2 mm/a以内，可有效反映该区域的地壳运动情况。

2) 总体上看，郯庐断裂带南段以西除阜阳、徐州、枣庄等地外，大部分地区呈面膨胀状态，以东地区大多表现为面压缩状态。根据最大分解尺度下的主应变率/面膨胀率和最大剪应变率的分布情况可以看出，应变方向变化异常的地区，均出现在面膨胀与面压缩的交界地带。最大剪应变率沿郯庐断裂带南段两侧呈对称分布，其西北和东南地区为高值区域，构造特征复杂，存在着较大的应变积累，有发生地震的可能，应予以关注。

3) 郯庐断裂带南段主要表现为右旋走滑，且北部存在着拉张，拉张分量向南逐渐递减，在最南部转变为压缩的状态。平行断裂的运动速率为0.10~1.21 mm/a-1，垂直断裂的运动速率为-0.52~0.76 mm/a。

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Analysis of Crustal Deformation and Fault Activity Characteristics in the Southern Segment of Tanlu Fault Zone with AHCORS
CHEN Hao1     TAO Tingye1     LI Shuiping1     LI Jiangyang1     SHI Mengjie1     GAO Fei1
1. College of Civil Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei 230009, China
Abstract: Using GAMIT/GLOBK software, we process the observation files of 37 AHCORS reference stations during Jan. 2013 and June 2018, and obtain the velocity fields of the stations under ITRF2008 and Eurasia frameworks. The error between the velocity field simulated by multi-scale spherical wavelet and the actual velocity field is less than 2 mm/a, indicating that this method effectively reflects crustal movement in this region. We use multiscale spherical wavelet to calculate and analyze the strain rates of the southern segment of the Tanlu fault zone and its surrounding areas. The results show that most of the areas west of the southern segment of the Tanlu fault zone are compressed, while most of the areas east of the Tanlu fault zone are dilatated in general. The abnormal variation of strain direction is located at the junction of plane expansion and plane compression. The maximum shear strain rate is symmetrically distributed along both sides of the southern segment of the Tanlu fault zone, and the northwest and southeast regions are high value regions with large strain accumulation and the possibility of earthquake, to which more attention should be paid. The southern segment of the Tanlu fault zone is mainly dextral strike-slip, there is tension in the north, the tensile component gradually decreases in the south, and the southernmost part turns into compression state.
Key words: AHCORS; velocity field; spherical wavelet; strain; velocity profile