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本文主要介绍１９９２年中美喜马拉雅和青藏高原深剖面与综合研究项目第一阶段（ＩＮＤＥＰＴＨＩ－１）广角地震观测资料利用Ｓｅｉｓ８１程序（Ｃｅｒｖｅｎｙ，１９８１）进行二维解释所获得的帕里一达吉地带的上地壳结构特征。主要成果为：（１）前寒武结晶基底之顶界表现为Ｒ１界面。据本项目地质调查，藏南拆离系（ＳＴＤＳ）在帕里以北约１０ｋｍ处出露，向北缓倾并向地下延伸。认为Ｒ１界面不仅是结晶基底之顶界的反映，而且ＳＴＤ可能沿着Ｒ１界面展布，也即Ｒ１界面同时是一条沉积盖层和基底之间的拆离层。Ｒ１界面埋深３±０．６—１１±０．６ｋｍ。（２）上述拆离层在萨马达一达吉之间，以Ｒ１界面之上的负速度梯度楔状体（ＬＶＬ）为特征。ＬＶＬ可能是ＳＴＤＳ活动时拖带下沉的中生代特提斯沉积，或可能是含水破碎带。（３）在结晶基底内部存在第二条拆离带（ＬＶＺ），表现为Ｔ２反射波组。ＬＶＺ在帕里埋深８．５±０．６ｋｍ，向北陡倾，至萨马达为２２．５±０．６ｋｍ深；再向北，倾角变缓，至达吉之下，达２７±０．６ｋｍ深。ＬＶＺ在帕里─萨马达之间，厚仅０．５ｋｍ；至达吉，增厚至５ｋｍ；也具楔形负速度梯度带性质；它可能是花岗岩局部融熔体之反映。（４）在萨马达─达吉?
In this paper, we mainly introduce the Pari-Dagi Strip, which was obtained by using the Seis81 program (Cerveny, 1981) for 2D seismic interpretation of the first-stage INDEPTHI-1 seismic data of the Himalayan and Tibetan Plateau in 1992. Upper crustal structural features. The main results are as follows: (1) The top boundary of pre-Cambrian crystalline basement is R1 interface. According to the geological survey in this project, the South Tibet Detachment System (STDS) is exposed at about 10km north of Parry, gently easterly and extend underground. It is believed that the R1 interface is not only a reflection of the top of the crystalline substrate, but also the STD may be distributed along the R1 interface, ie, the R1 interface is also a detached layer between the sedimentary cover and the substrate. R1 interface buried depth 3 ± 0.6-11 ± 0.6km. (2) The above detachment layer is located between the Darma of Samada and the negative velocity gradient wedge (LVL) above the R1 interface. LVL may be a sinking Mesozoic Tethyan sediment during STDS activity or may be a watery fractured zone. (3) There is a second detachment zone (LVZ) inside the crystalline basement, which is manifested as T2 reflected wave group. LVZ buried in Pari 8.5 ± 0.6km steeply northward to Samada 22.5 ± 0.6km deep; further northward, the dip angle slowed down to reach 27 ± 0 under Daji. 6km deep. The LVZ is between Parry-Samada, only 0.5km thick; up to Kat, thickening up to 5km; it also has a wedge-shaped negative-gradient gradient zone; it may be a reflection of local melting of granite. (4) At Samanda-Dag?