陆上三维地震勘探的实践

3-D LAND OPERATIONS

为了解决复杂构造勘探问题和地层岩性勘探问题,提高勘探的详细度和准确度以及勘探工作的总效果,我们以EM地区为基地进行了陆地三维地震勘探方法技术试验研究,取得了基本成果。本文就野外工作、资料处理、成果解释以及效果分析几个方面做一些初步介绍。研究工作成果,从理论上和实践上证实了三维地震勘探应用的必要性以及在我国当前条件下用现有的观测设备和小型数处系统进行采集和处理三维资料的现实可行性。文中着重论述了选择合适的观测系统、速度参数在三维偏移处现中的重要性,用二步法偏移代替全三维偏移的精度和效率,某些特殊的三维显示和解释方法,并对三维地震做出初步评价及指出今后我国在能源地质普查、勘探和开发各阶段中,在构造勘探和地层岩性勘探的工作上都存在着要进行三维地震勘探工作的客观需要,因此积极地逐步推广一套三维地震方法技术是我国地震勘探发展中一个十分重要的问题。

In order to solve the problems about the complex structure exploration as well as the stratigraphic and lithologic exploration, and, to make the work more detail and accurate so as to improve the effects, some experiments and tests of 3-D land operations have been made in EM region and primary positive results have been achieved. What was briefly introduced in this paper is: the field work, the data processing and interpretation as well as the analysis of the results.It has been shown theoretically and practically that in our country the application of 3-D seismic exploration is necessary and the acquisition and processing of 3-D data by means of the available equipment and the minicomputer system are acceptable.The selection of the proper layout, the importance of the parameters of velocity in 3-D migration, the accuracy and effectiveness of the replacement of 2-step migration for full 3-D migration, some special means of 3-D display and 3-D interpretation were discussed in full and stressed in particular. Evaluation for 3-D seismic exploration has also been made. It is obvious that there’s a need for carrying out the 3-D seismic exploration in the phases of reconnaissance survey, exploration and development and in the structural as well as the lithologic exploration. Therefore, to actively popularize the 3-D seismic exploration in order is very important in the course of our seismic exploration.