河北地区地壳一维速度模型的新近研究

Study on One-dimensional Crustal Velocity Model in Hebei Area

为建立更适合河北地区地震速报及编目的地壳一维速度模型,收集河北数字地震台网2009年1月至2014年10月定位台站数N≥10,震级M≥1.0的1 113条地震以及精选的48条地震;利用滑动窗拟合、折合走时等方法及结合前人研究成果确定一维速度模型中各参数的范围,并利用Hyposat批处理程序,对精选的48条地震进行了58 902次组合计算,对残差最小的10组数据利用与编目结果震中位置偏差大小为原则进行筛选,由此建立了适应河北地区地震速报及编目的地壳一维速度新模型;然后利用批处理残差大小比较、PTD深度定位、爆破检验、典型地震检验等方法对其验证。结果表明,相较于华南模型,新模型更适用于河北地区。

In order to establish a more appropriate one‐dimensional velocity model for the earthquake quick reporting and compiling catalogue in Hebei Seismometry Network ,1113 earthquakes with the positioning station number over 10 and the M magnitude over 1were collected and 48 earthquakes were selected from January 2009 to October 2014 .Firstly ,the range of parameters in one‐dimensional velocity model was got by the methods of the sliding window fitting ,the travel time reducing and referring to some previous reearches .Secondly ,to establish the new model of Hebei by the program of Hyposat Batching with the 48 selected earthquakes for 58902 calculations .The new velocity model was established according to the criterion ,that the residual of the calculation was minor and the deviation of epicenter between the calculation and the compiling catalogue was minimum .Thirdly ,the new velocity model was examined by the comparison of residual results ,the depth positioning by the PTD ,the blast events and the typical earthquakes and so on .It was shown that comparing to the South‐China mode the new velocity model is more in conformity with the geological feature in Hebei area .