八达岭及周缘地区壳幔结构与潜在震源探讨

DISCUSSION ON STRUCTURE OF CRUST AND UPPER MANTLE AND POTENTIAL FOCAL REGION IN BADALING AND ITS NEIGHBORHOOD

摘要:

利用Seis83程序包,对盐山-大兴-延庆剖面的大兴-延庆段人工地震测深资料进行了计算处理,获得了八达岭及周缘地区地壳上地幔结构.结果显示,该区浅部断裂发育,沉积层厚度差别大;其深部构造在横向上存在着明显的不均匀性,速度等值线起伏变化明显,局部存在低速块体.莫霍面由剖面东段的大兴向延庆方向倾斜,大兴附近莫霍面的深度为34.5km,居庸关附近为38.5km.在延庆附近莫霍面存在一断裂.

Abstract:

The Seis83 programs were used in order to calculate the DSS data of Daxing-Yanqing section in Yanshan-Daxing-Yanqing profile.The structure of crust and upper mantle was obtained in Badaling and its neighborhood.The result shows that in the region,faults well developed and there is much difference in thickness of deposition layer in the shallow crust,crust structure is heterogeneous in crosswise and undulate changes of crust interface and velocity isopleth are obvious in depths,low velocity blocks exist in the partial crust.The depth of Moho discontinuity in Daxing is about 34.5 km and that in Juyongguan is about 38.5 km.A fault of Moho exists in vicinity of Yanqing.