摘要
深层高陡地层中零井源距垂直地震剖面(vertical seismic profiling, VSP)初至波出现分叉现象或复波等异常,造成传统VSP初至拾取方法已无法满足处理要求。针对该类特征零井源距VSP初至波拾取面临的难题,通过数值模型正演分析明确深层高陡地层零井源距VSP初至波产生异常的原因。其原因是地层倾角较大时,沿远离井筒的地震波通过高速地层比垂直入射波先到达检波点所至,且地层倾角越大、界面上下介质速度差越大,初至分叉越明显,与实际资料中展示的初至波场特征一致。在此基础上提出了基于正演模式导向的沿浅层“首波”同相轴连续向下拾取的策略,在塔里木盆地中寒1井VSP处理中应用,取得良好的应用效果。
In deep and high-steep formation, the first arrival wave of vertical seismic profiling(VSP) with zero well spacing appears bifurcation phenomenon or multiple wave, which makes the traditional VSP first arrival picking method unable to meet the processing requirements. Aiming at the problem of first-arrival pickup of zero-offset VSP, Numerical modeling analysis method was used to clarify the reason for the anomaly of zero offset VSP first-arrival wave in deep high and steep formation, because the formation dip angle is larger, the seismic wave far away from the wellbore reaches the geophone before the vertical incident wave through the high-speed formation, and the larger the formation dip angle is, and the greater the difference between the upper and lower medium velocities is, and the more obvious the bifurcation phenomenon is. The numerical simulation results are in agreement with the first-arrival field characteristics shown in the actual data. Then on the basis of this, a strategy of continuous downward picking along the shallow “first wave” in-phase axis based on forward modeling is proposed, which has been applied in the zero-offset VSP processing of Zhonghan 1 well in Tarim Basin and achieved good application effect.
作者
张振
蔡涵鹏
王腾宇
肖又军
宗晶晶
黄录忠
魏巍
ZHANG Zhen;CAI Han-peng;WANG Teng-yu;XIAO You-jun;ZONG Jing-jing;HUANG Lu-zhong;WEI Wei(Research Institute of Exploration and Development,Tarim Oilfield Company,PetroChina,Korla 841000,China;School of Resources and Environment,University of Electronic Science and Technology of China,Chengdu 611731,China;Laboratory of Intelligent Oil and Gas Geophysics of UESTC-AIWe BEST,Chengdu 611731,China)
出处
《科学技术与工程》
北大核心
2022年第27期11820-11828,共9页
Science Technology and Engineering
基金
国家自然科学基金重点项目(42130812)
国家自然科学青年科学基金(42104130)。
关键词
零井源距VSP
初至拾取
高陡地层
层速度
zero-offset VSP
first break picking
deep and high-steep formation
interval velocity
