巴塘国家基本数字地震台数字地震仪记录近震震级偏差分析与校正

Analysis and Correction of Magnitude Deviation of Near Earthquakes Recorded by Digital Seismometer at Batang Station

分析了巴塘国家基本数字地震台2009年1月初至2012年12月底测定的ML≥2.5级的近震544个,与中国地震台网中心(CSN)发布的ML震级之间的偏差,计算出了震级偏差程度,本台近三分之一地震震级偏差达0.3级,文章着重从地震发生的方位角不同和地动位移不同,找出了震级相差很大的原因,最后给出了本台的校正值。通过本台校证,震级接近了中国地震台网中心发布的ML震级,提高了本台地震震级测定的准确性。

In this paper, we analyzed the deviations between the 544 ML2.5 earthquakes recorded by Batang station from January, 2009 to December, 2012 and ME magnitudes released by CENC, and the degree of deviations of magnitudes were figured out. We found that one third of the earthquake＇s magnitude deviations at Batang station reached to 0.3. Mainly based on differences of azimuth and ground displacement of the earthquakes, reasons for great magnitude differences were indicated and correction value was finally obtained. Through the correction values, the magnitude differences between records observed by Batang station and that released by CENC become smaller, which shows that correction method could improve the accuracy of magnitude observed by our station.