高陡构造地区勘探失误分析及速度建模改进方法----以云安10井为例

Prospecting defect analysis and improving technology for velocity modeling in high-steep structure area: case study of Yun’an10 well

（1．重庆科技学院，重庆400042；2．中国石油化工股份有限公司石油勘探开发研究院，北京100083；3．川庆钻探工程公司地球物理勘探公司物探研究中心，四川成都610212）

ChongQing University of Science and Technology, Chongqing 400042, China

四川盆地东部地区地下构造较复杂，构造模式多样，普遍存在高陡构造。在地震资料的处理和解释中，用于时深转换的速度模型对高陡构造的成像精度影响很大。介绍了针对高陡构造地区的地震勘探技术，探讨了高陡构造成像中存在的问题，并以YB地区云安10井钻探失误为例，探讨了速度模型对高陡构造成像的影响，提出了利用速度控制点法建立速度模型的改进措施。利用改进后的速度模型，对YB地区高陡构造原地震资料进行了目标性处理，地震解释深度与钻井基本吻合。将新的构造解释结果与原构造解释结果进行了对比分析，新构造解释结果与钻井吻合较好，进一步落实了YB地区东翼大断层下盘各潜伏构造的形态、圈闭规模、高点位置和隆起幅度。

Subsurface structures are complex in east Sichuan basin with high-steep structures being commonly seen. In seismic data processing and interpretation, the velocity model for time-depth conversion largely affects the imaging accuracy for these structures. The seismic prospecting technologies aiming at high-steep structure area are introduced, and the existing problems in the imaging of high-steep structures discussed. Taking the failure prospecting of Yun’an10 well in YB area as an example, the effect of velocity model on high-steep structure imaging was probed, and improving measures were proposed, that is using the velocity controlling points method to establish velocity model. The improved velocity model was used to reprocess the original seismic data of high-steep structures in YB area, showing that the seismic interpreted depth is coincided with drilling data, which further identified the structural configuration, trap scale, high focus position, and uplift relief of buried structures on the dropped side of Dongyi fault in YB area.