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利用北京台网３８个台站记录的北京及其附近地区１９９０～１９９３年３０３个２０级（唐山地区３０级）以上地震，共３０１４条Ｐ波到时、６６６条Ｐｎ波到时及１１３５条Ｓ波到时资料，采用Ｈｏｒｉｕｃｈｉ等（１９８２ａ；１９８２ｂ）提出的“地壳二维深度结构”方法，研究了这一地区Ｍｏｈｏ面的深度分布特征，同时联合测定震源位置及Ｐ，Ｓ波台站校正值。另外，用华北台网（１９９３，１９９４年）的资料也进行了试算。结果表明：（１）Ｍｏｈｏ面的深度分布明显由西北向东及东南方向递减，即北部山区张家口附近最深，可达４０～４２ｋｍ左右，北京地区为３６～３９ｋｍ，而位于东部的秦皇岛、北戴河一带则约为２８～３０ｋｍ，东南部约为３０～３２ｋｍ；（２）在唐山附近有一以唐山为中心、东西向为长轴、南北向为短轴的近似椭圆形分布的界面（约１°×２°），该界面边界模糊，中心深度约为１３～１５ｋｍ；（３）山区部分基岩裸露，凹陷区沉积岩层相对较厚，最厚约为６２ｋｍ。
A total of 3014 P waves arrived in Beijing and its vicinity from 303 stations of 20 in 1990 ~ 1993 (30 in Tangshan area) recorded by Beijing station and 38 stations, and 666 Pn waves arrived And 1135 S-wave arrival data, the depth distribution of the Moho surface in this area was studied by using the method of “two-dimensional Crustal structure” proposed by Horiuchi et al. (1982a; 1982b) Station correction value. In addition, with the North China Network (1993, 1994) data also conducted a trial. The results show that: (1) The depth distribution of Moho surface obviously decreases from northwest to east and southeast, which is the deepest near Zhangjiakou in the northern mountains, reaching 40-42km, while Beijing is 36-39km. In the eastern part of Qinhuangdao and Beidaihe About 28 ~ 30km, southeastern about 30 ~ 32km; (2) near the Tangshan Tangshan as a center, east-west long axis, north-south axis of the approximate minor axis of the distribution of the interface (about 1 ° × 2 °), the boundary of the interface is fuzzy and the center depth is about 13-15 km. (3) Some basement rocks in the mountain area are bare and the sedimentary rock layers in the depression area are relatively thick with a maximum thickness of about 62km.