Zemin Liu , Weitao Wang , Lu Li , Zihao Li , Ziye Yu , Songyong Yuan , Lanshu Bai
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引用次数: 0
Abstract
The aftershocks of the 1975 MS7.3 Haicheng and 1999 MS5.4 Xiuyan earthquakes have persisted for a long time. The ChinArray-III dense stations, deployed in eastern North China from 2018 to 2020, increased seismic monitoring capability in the Haicheng-Xiuyan region, which can facilitate the construction of high-precision earthquake catalogs to better clarify the fault structures and seismogenic mechanisms of the two earthquakes. In this study, we selected 15 permanent stations and 37 ChinArray-III stations within 150 km of the epicenter of the Haicheng Earthquake. Next, we used deep learning methods to pick P- and S-wave phases from continuous waveforms recorded at these stations from January 2018 to July 2020. Based on these picks, we constructed an automatic earthquake catalog of the Haicheng-Xiuyan region. Compared with the routine manual catalog by China Earthquake Networks Center (CENC), our catalog contains 9.7 times more seismic events, including 98.3% of the seismic events in the CENC catalog, and has a lower magnitude of completeness (Mc = 1.1 vs Mc = 1.8 for the CENC catalog). The relocated events indicate that the strike of the Haichenghe-Dayanghe fault varies considerably from northwest to southeast, indicating that the fault bends slightly around the hypocenter of the 1975 MS7.3 Haicheng earthquake which may act as a channel for fluid migration. The weak seismicity in the area between Haicheng and Xiuyan indicates that the fault section may be locked. Furthermore, the 1999 MS5.4 Xiuyan earthquake and its aftershock sequence occurred on the Kangjialing fault and its ENE-trending conjugate fault, and the intersection of the two faults coincides with the source areas of the 1999 MS5.4 and 2000 MS5.1 Xiuyan earthquakes. Therefore, the Xiuyan earthquake sequence may be controlled by the Kangjialing fault and its conjugate fault. This study shows that the automatic earthquake catalog, obtained by deep learning methods and dense seismic array, can provide valuable information for fault structures and the seismogenic mechanisms of moderate-to-strong earthquakes.
期刊介绍:
Earthquake Science (EQS) aims to publish high-quality, original, peer-reviewed articles on earthquake-related research subjects. It is an English international journal sponsored by the Seismological Society of China and the Institute of Geophysics, China Earthquake Administration.
The topics include, but not limited to, the following
● Seismic sources of all kinds.
● Earth structure at all scales.
● Seismotectonics.
● New methods and theoretical seismology.
● Strong ground motion.
● Seismic phenomena of all kinds.
● Seismic hazards, earthquake forecasting and prediction.
● Seismic instrumentation.
● Significant recent or past seismic events.
● Documentation of recent seismic events or important observations.
● Descriptions of field deployments, new methods, and available software tools.
The types of manuscripts include the following. There is no length requirement, except for the Short Notes.
【Articles】 Original contributions that have not been published elsewhere.
【Short Notes】 Short papers of recent events or topics that warrant rapid peer reviews and publications. Limited to 4 publication pages.
【Rapid Communications】 Significant contributions that warrant rapid peer reviews and publications.
【Review Articles】Review articles are by invitation only. Please contact the editorial office and editors for possible proposals.
【Toolboxes】 Descriptions of novel numerical methods and associated computer codes.
【Data Products】 Documentation of datasets of various kinds that are interested to the community and available for open access (field data, processed data, synthetic data, or models).
【Opinions】Views on important topics and future directions in earthquake science.
【Comments and Replies】Commentaries on a recently published EQS paper is welcome. The authors of the paper commented will be invited to reply. Both the Comment and the Reply are subject to peer review.