选取2019—2020年西藏、云南、四川、青海、新疆地震台网记录的MS≥5.5远震事件P波数据，采用P波质点运动方法，计算中国西北、西南地区211个地震台站方位角及其随时间的变化。结果显示，约53%的台站方位角偏差绝对值始终小于3°，运维状况极佳；约39%的台站方位角偏差绝对值保持在3°—10°，运维良好；约9%的台站方位角偏差绝对值大于10°，少数台站存在极性反转等现象。在运行维护过程中，部分台站受到更换或移动地震计等人为因素的影响，地震计方位角出现短时跳变现象。为保证地震数据的可靠性，应定期对台站方位角进行检查和校正，以便为地震学研究提供可靠的基础数据。
P-wave data from teleseismic events with MS ≥ 5.5 were collected from the seismic networks in Tibet, Yunnan, Sichuan, Qinghai, and Xinjiang between 2019 and 2020.Utilizing the P-wave particle motion method, the azimuth angles of 211 seismic stations in the northwest and southwest regions of China, and the variations over time, were calculated. The results show that approximately 53% of the stations exhibited excellent performance, with azimuth deviations smaller than 3° from the true north;about 39% of the stations showed good performance, with azimuth deviations ranging from 3° to 10°; approximately 9% of the stations have azimuth angle deviations with absolute values larger than 10°, with a few stations exhibiting phenomena such aspolarity reversal. During operation and maintenance, some seismic instruments were affected by human factors such as the replacement or relocation of seismometers, leading to short-term abrupt changes in the seismometer's azimuth angle. To ensure the reliability of seismic data, it is recommended to periodically check and calibrate the azimuth angles of the stations, thus providing reliable foundational data for seismological research.
2023,44（4）: 1-8 收稿日期：2023-05-09
DOI：10.3969/j.issn.1003-3246.2023.04.001
基金项目：中国地震局地震科技星火计划项目（项目编号：XH233707YB）；中国地震台网中心青年科技基金（项目编号：QNJJ-202220）
作者简介：韩光洁(1993-),工程师,主要从事地震监测和震源物理学方面的研究。E-mail:hangj@seis.ac.cn
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