利用PMC方法评估海南测震台网地震监测能力

Assessment of Earthquake Monitoring Capability of Hainan Seismic Network Based on PMC Method

利用“基于概率的完整性震级”PMC方法,采用海南测震台网地震编目报告数据和台站资料,计算了海南测震台网21个台站对海南岛陆及周边海域地震的检测概率、测震台网的合成检测概率及最小完整性震级。单台检测概率结果显示:由于受台站布局、台基等因素影响,海南岛陆中部台站的检测能力较强,琼北地区4个火山口台和三亚台检测能力差。合成检测概率及最小完整性震级结果显示:以屯昌为中心点以及周边的琼中、文昌、定安地区为检测高值地区;接入广东广西共享台,海南岛陆90%的地区基于概率的最小完整性震级M_(P)达到M_(L)1.5左右,海南岛陆西南部分地区及海岸线50 km范围内M_(P)达到M_(L)2.0左右。结果表明:海南岛陆中北部地震监测能力较强,西南部及周边海域地震监测能力较弱,研究结果希望能为进一步优化海南测震台网布局提供一些参考依据。

In this paper,using the PMC method of"probability based integrity magnitude"and the earthquake cataloging report data and station data of Hainan Seismic Network,the detection probability of 22 stations of Hainan Seismic Network for earthquakes on the land of Hainan Island and the surrounding sea area,the synthetic detection probability of seismic network and the minimum integrity magnitude are calculated.The results of single station detection probability show that due to the influence of station layout,station foundation,site response and other factors,the detection ability of stations in the central land of Hainan Island is strong,while the detection ability of four volcanic vent’s stations and Sanya Station is poor.The results of synthetic detection probability and minimum integrity magnitude show that Tunchang is the central point and surrounding Qiongzhong,Wenchang and Ding'an areas are the high detection value areas;with access to Guangdong and Guangxi shared station,the probability based minimum integrity magnitude M_(P) of 90%of Hainan Island reaches about M_(L)1.5,M_(P) in some areas in the southwest of Hainan Island and within 50 km of the coastline reaches about M_(L)2.0.The results show that the seismic monitoring ability in the northern part of Hainan Island is strong,and the seismic ability in the southwest and surrounding sea areas is weak.The research results of this paper hope to provide some reference for further optimizing the layout of Hainan seismic network.