Study On Seismic Exploration Field Acquisition Method In Complicated Front-zone Of Mountain

Owing to complicated earth's surface condition such as the steep stratum outcropping of front-zone of mountain or the huge thick gravel stratum's overlay and earth's surface large undulation, complicated underground geology structure developed extremely such as thrust and overthrust nappe, and violent change of the lateral velocity, etc. In front-zone of mountain there are a series of problems such as serious secondary disturbance and low signal-to-noise ratio in seismic exploration gathering.In recent years, along with the improvement of equipment and technology of seismic exploration, the technology of acquisition seismic data has a new development. The major technology and method of field gathering in the complicated area has: many kinds of focuses exciting method jointly ( exploding in the well and the big tonnage vibrator); the exciting method about selecting points based on the earth's surface condition and investigating surface level; the receiving method about the small intervals between the detector and long arranges and high overlays; designing method based on the model about observation system objective in section, in line and in area.In order to make the studying about the seismic exploration method possess systematic nature and the ability of tackling key problem in front-zone of mountain, we have done the research work of tackling key problem aiming at the field gathering technology of seismic exploration of the complicated structure belt (the construction of underground and the earth's surface condition are complicated) of front-zone of mountain in this text, and a large number of relativity trials by the close combination of production and scientific research , summarized a set of field method of the complicated structure belt of front-zone of mountain, adjusted both of trial factor and construction factor of the field gathering in time, achieved finally the goal of making its structure character clear.According to the trait of seismic-geology condition of front-zone of mountain and universal problems that exist in the real data, we have studied the following several aspects:1. To do the investigating and studying work about the achievements of tackling key problem of the quondam exploration of front-zone of mountain, to analyze and study the applicability about the gathering technology used in the seismic exploration of the complicated construction belt of front-zone of mountainous;2. Combining the quondam achievements, researching the design method of observation system objective of the complicated construction belt based on seismic-geology model, firstly, building the surface level and deep layer seismic-geology model of complicated construction belt and analyzing the forwardmodel, secondly, designing the observation system aiming at the overthrust nappe structure in section and in area;3. Aiming at the complicated earth's surface condition of front-zone of mountain, how to select the exciting method and the parameter, how to optimize the environment of exciting method and reception, how to pledge the normal combination of the datum of different exciting method;4. Research of static correction method and investigation technology about the surface stratum structure of huge thick gravel area of front-zone of mountain. Studying the practicable investigation method of surface stratum and applying for the actual production aiming at the surface stratum characteristics of the different areas of front-zone of mountain in the west.By way of theory research and tackling key problem about the gathering technology of field seismic datum, forming a series of advanced and practical gathering method and technology in the complicated front-zone of mountain, gaining obvious geology effect.