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喀什凹陷北缘是塔里木盆地西南地区油气勘探的有利区带之一。由于该区的地震地质条件具有地形起伏大、山前巨厚砾石堆积、表层结构和地下构造复杂的特点，在该区采集的地震资料普遍存在信噪比低造成构造主体部位成像不清的问题。提高地震原始资料的信噪比是该区地震工作的首要任务。文章采用多种方法和“循环迭代式”的流程调查表层结构，通过循环调查、迭代建模的方法，有效地提高表层结构模型的精度；根据表层结构模型逐点设计激发、接收参数，保证在高速层中激发和检波器与岩层的良好耦合；综合利用表层结构模型、地面地质资料、高精度卫片资料以及地震资料，对激发、接收条件分区，并按照 “按能分配”的原则对炮点、检波点进行转移和再分配，以优选激发、接收条件；应用这些技术在该区进行地震攻关，使地震原始资料的信噪比和关键构造部位的成像质量较以前有明显的提高。

SEISMIC ACQUISITION METHODS OF COMPLICATED MOUNTAIN LANDS ALONG THE NORTH MARGIN OF KASHI DEPRESSION

The north margin of Kashi Depression is one of the beneficial zones of oil and gas exploration in Southwest Talimu Basin.In the region,the problem of structural major portion′s unclear imaging caused by low signal to noise ratio existed commonly in the seismic data acquired because of the unfavourable seismic geological conditions,such as great morphologic prominence,huge thickness piedmont gravel buildup,and complicated surface structure and ground structures,etc.It is the most important task in seismic exploration in this region to raise the signal to noise ratio of original seismic data.The surface structure was surveyed by use of various methods and “circulating iteration” procedure.The accuracy of surface structure model was effectively raised through circulating survey and iteratively modeling;the shooting and receiving parameters were designed point by point according to the surface structure model,thus ensuring the excitation in high velocity layer and a good coupling of geophone with rock;the excitation and reception conditions were divided by applying comprehensively the surface structure model,surface geological data,high accuracy extraterrestrial photograph data and seismic data,and the rtansposition and redistribution of the shot points and receivers were carried out in light of the principle of “distribution according to energy” so as to optimize the excitation and reception conditions;the qualities of the signal to noise ratio of seismic data and the structural major portion imaging were obviously raised through overcoming the key seismic projects by applying these techniques.