﻿ 中国大陆地倾斜形变台视偏角时空特征初步研究
 文章快速检索 高级检索
 大地测量与地球动力学  2024, Vol. 44 Issue (2): 202-208  DOI: 10.14075/j.jgg.2023.04.159

### 引用本文

LIU Jinrui, SHEN Xuzhang, TANG Jiu'an, et al. A Preliminary Study on the Temporal and Spatial Characteristics of the Apparent Deflection Angle of Earth Tilt Deformation Stations Mainland China[J]. Journal of Geodesy and Geodynamics, 2024, 44(2): 202-208.

### Foundation support

National Natural Science Foundation of China, No.42230305; The Second Tibetan Plateau Scientific Expedition and Research Program (STEP), No.2019ZQKK0701.

### Corresponding author

SHEN Xuzhang, professor, PhD supervisor, majors in seismology and fixed-point deformation, E-mail: shenxzh5@mail.sysu.edu.cn.

### 第一作者简介

LIU Jinrui, postgraduate, majors in analysis of fixed-point deformation data, E-mail: 1668066251@qq.com.

### 文章历史

1. 中山大学地球科学与工程学院，广东省珠海市情侣北路，519000;
2. 南方海洋科学与工程广东省实验室(珠海)，广东省珠海市情侣北路，519000;
3. 甘肃省地震局，兰州市东岗西路450号，730000

1 视方位角的定义与计算 1.1 视方位角与NAKAI拟合结果

 \begin{aligned} v_t & =a R_t+b R_t^{\prime}+\sum\limits_{l=0}^2 k_l t^l-Y_t \\ b & =a \cdot \mathrm{d} t \end{aligned} (1)

 \begin{aligned} & R_t=g_{\mathrm{NS}} \cos A+g_{\mathrm{EW}} \sin A \\ & R_t^{\prime}=g_{\mathrm{NS}}^{\prime} \cos A+g_{\mathrm{EW}}^{\prime} \sin A \end{aligned} (2)

1.2 视方位角的定义与计算

 图 1 北京西拨子地倾斜理论值和观测值对比曲线 Fig. 1 Comparison curve between theoretical and observed values of ground tilt at Beijing Xibozi

 图 2 北京西拨子理论值随方位角变化曲线 Fig. 2 The oretical value variation curve with azimuth at Beijing Xibozi

 图 3 理论值与观测值振幅比和滞后因子随方位角变化动态曲随线 Fig. 3 The dynamic curve of the amplitude ratio and hysteresis factor between theoretical and observed values as a function of azimuth angle

1.3 方位角偏差对NAKAI拟合结果的影响

1.4 地倾斜视偏角

2 西拨子和兰州地倾斜视偏角计算结果

 图 4 西拨子台三分量视偏角对比 Fig. 4 Comparison of the 3 component apparent declination angles of the Xibozi station

 图 5 十里店台站两分量视偏角对比 Fig. 5 Comparison of the 2 component apparent declination angles at the Shilidian station

3 全国地倾斜台网2020年度视偏角计算结果 3.1 数据概况

3.2 视偏角PS的大小分区统计结果

 图 6 2020年度视偏角PS的大小分区统计结果 Fig. 6 Size zoning statistics for the 2020 apparent declination PS
3.3 视偏角离散误差MPS的大小分区统计结果

 图 7 视偏角离散误差MPS的大小分区统计结果 Fig. 7 Statistical results of the size partition of the dispersion error MPS for visual declination

 图 8 水平摆倾斜结果分布 Fig. 8 Distribution of tilting results of horizontal pendulum

 图 9 垂直摆倾斜仪结果分布 Fig. 9 Distribution of vertical pendulum tiltmeter results

 图 10 水管倾斜仪结果分布 Fig. 10 Distribution of water pipe tiltmeter results

 图 11 井下摆倾斜仪结果分布 Fig. 11 Distribution of underground pendulum tiltmeter results
3.4 几个测向分量视偏角异常的原因初步分析

4 结语

1) 基于NAKAI最佳拟合结果确定的地倾斜视方位角AS是地倾斜固体潮观测数据中的重要属性参数，可以判断起始方位角A0的准确性，并检验观测数据内在质量的可靠性；

2) 1987~2020年西拨子和十里店水管倾斜仪观测数据计算结果表明，西拨子NS向视偏角PNS=－0.1°，EW向视偏角PEW=9.6°，NE向视偏角PNE=12.4°；十里店NS向视偏角PNS=0.3°，EW向视偏角PEW=－22.5°。

3) 2020年全国地倾斜台网715个测向分量观测数据计算结果表明，视偏角PS＜10°的分量数为266个，占37.20%；PS＜22.5°的为445个，占62.24%；PS＞45°的为111个，占15.52%；视偏角离散误差MPS＜10°的分量数为247个，占34.55%；MPS＜22.5°的为446个，占62.38%；MPS＞45°的为43个，占6.01%。根据水平摆倾斜仪、垂直摆倾斜仪、水管倾斜仪及井下摆倾斜仪结果分布认为，四类仪器在NS向的结果优于EW向，垂直摆倾斜仪两分量的差异尤其明显，个别仪器的视偏角接近90°，需要重新筛查数据质量。

4) 当视方位角偏差为10°时，拟合振幅比偏差约为3%，滞后因子约为20 min；当视方位角偏差为20°时，拟合振幅比偏差约为12%，滞后因子约为39 min；当视方位角偏差为45°时，拟合振幅比偏差约为44%，滞后因子约为63 min；当视方位角偏差为90°时，拟合振幅比偏差约为97%，滞后因子约为68 min。因此，建议对于视偏角大于20°的测向分量的起始方位角应予以重点核查；对于视偏角离散误差大于20°的测向分量的观测数据应进行认真筛查。

5) 当视偏角出现异常(PS＞45°)时，应首先核查使用的真方位角AZ0是否正确，此时利用视方位角AS校核方位角A0有一定的效果。

 [1] 中国地震局. 地震与地震前兆预测分类与代码DB/T 3-2003[S]. 北京: 地震出版社, 2003 (China Earthquake Administration. Classification and Code for Earthquake and Earthquake Precursor Prediction—DB/T 3-2003[S]. Beijing: Seismological Press, 2003) (0) [2] 中国地震局. 地震台站代码DB/T 4-2003[S]. 北京: 地震出版社, 2004 (China Earthquake Administration. Seismic Station Code-DB/T 4-2003[S]. Beijing: Seismological Press, 2004) (0) [3] 陈德福. 我国的水管仪倾斜固体潮观测[C]. 2004年重力学与固体潮学术研讨会暨祝贺许厚泽院士70寿辰研讨会, 武汉, 2004 (Chen Defu. Inclined Earth Tide Observation with Water Tube Instrument in China[C]. 2004 Academic Conference on Gravity and Earth Tide and Seminar on the 70th Birthday of Academician Xu Houze, Wuhan, 2004) (0) [4] 中国地震局. 地震及前兆数字观测技术规范-地壳形变观测: 试行[S]. 北京: 地震出版社, 2001 (China Earthquake Administration. Technical Specification for Digital Observation of Earthquakes and Precursors-Crustal Deformation Observation: Trial Implementation[S]. Beijing: Seismological Press, 2001) (0) [5] 沈旭章, 唐九安, 高安泰. 固体潮观测数据处理手册[Z]. 广州: 中山大学出版社, 2022 (Shen Xuzhang, Tang Jiuan, Gao Antai. Solid Tide Observation Data Processing Manual[Z]. Guangzhou: Sun Yat-Sen University Press, 2022) (0) [6] 唐九安. 固体潮观测数据的预处理[J]. 西北地震学报, 1981, 3(3): 73-77 (Tang Jiuan. The Pre-Processing Method of the Observation Data of Earth Tides[J]. Northwestern Seismological Journal, 1981, 3(3): 73-77) (0) [7] 唐九安. 天顶距微分公式用于重力、倾斜和应变固体潮资料的拟合检验[J]. 地壳形变与地震, 1990, 10(2): 1-8 (Tang Jiu'an. The Zenith Distance Formulas of the First Order Differential Quotient for the Theoretic Value of the Earth Tides Applied to the Fit-Testing of the Gravity, Tilter and Line Strain Earth Tides[J]. Crustal Deformation and Earthquake, 1990, 10(2): 1-8) (0) [8] 蒋骏, 张雁滨. 固体潮理论值一阶微商的解析表达式及拟合检验[J]. 地球物理学报, 1994, 37(6): 776-786 (Jiang Jun, Zhang Yanbin. A Differential Analytical-Representation of the Theoretical Value of Earth Tide and the Fit-Testing of Earth Tide Data[J]. Chinese Journal of Geophysics, 1994, 37(6): 776-786) (0) [9] 陆忠远, 李胜乐, 邓志辉, 等. 基于GIS的地震分析预报系统[M]. 成都: 成都地图出版社, 2002 (Lu Zhongyuan, Li Shengle, Deng Zhihui, et al. Earthquake Analysis and Prediction System Based on GIS[M]. Chengdu: Chengdu Cartographic Publishing House, 2002) (0)
A Preliminary Study on the Temporal and Spatial Characteristics of the Apparent Deflection Angle of Earth Tilt Deformation Stations Mainland China
LIU Jinrui1     SHEN Xuzhang1,2     TANG Jiu'an3     GAO Antai3
1. School of Earth Sciences and Engineering, Sun Yat-Sen University, North-Qinglü Road, Zhuhai 519000, China;
2. Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai), North-Qinglü Road, Zhuhai 519000, China;
3. Gansu Earthquake Agency, 450 West-Donggang Road, Lanzhou 730000, China
Abstract: Based on theoretical analysis, we propose the concepts of apparent azimuth and apparent declination of ground tilt, and introduce the procedure of calculating the apparent declination. We use the observed data of five measurement components of the water pipe tiltmeter from 1987 to 2021 in Beijing Yanqing Xibozi and Gansu Lanzhou Shilidian stations as examples. In turn, we calculate the results for the apparent declination of the 715 measured component observations of the national ground tilt network in 2020. Results from two typical stations show that: the Xibozi station NS direction angle of apparent declination PNS=－0.1°; EW direction angle of apparent declination PEW=9.6°; NE direction angle of apparent declination PNE=12.4°; the Shilidian station NS direction angle of apparent declination PNS=0.3°; EW direction angle of apparent declination PEW=－22.5°; the maximum apparent deflection angle of 2 stations is 23.2°, the minimum value is －36.0°. From the statistical mean of the 5 components, the maximum value of the apparent deviation angle is 12.4°, the minimum value is －22.5°, and the range is 34.9°. Both stations show that the number of apparent deflections in the NS direction is relatively small, while the number of apparent deflections in the EW direction and NE directions is relatively large. The calculation results of the observed data from the national earth tilt network indicate that there are 266 components with an apparent deviation angle PS < 10°, accounting for 37.20%, the number of components with an apparent deviation angle of PS < 22.5° is 445, accounting for 62.24%, and the number of components with PS>45° is 111, accounting for 15.52%; the number of components with apparent deviation angle dispersion error MPS < 10° is 247, accounting for 34.55%, the number of MPS < 22.5° is 446, accounting for 62.38%, and the number of components with MPS>45° is 43, accounting for 6.01%. Based on the results of this study, we recommend that the initial azimuth angle of the measurement component with an apparent deviation number greater than 20° should be emphatically checked; also we should carefully screen the observation data of the measurement component with an apparent deviation angle dispersion error MPS>20°.
Key words: geo-tilt apparent azimuth; geo-tilt apparent declination; annual statistical mean; annual statistical variance; NAKAI fit; best-fit state