WEFOX叠前成像技术及其在塔里木盆地塔中地区岩溶缝洞储层中的应用

Application of WEFOX Pre-stack Imaging Technique in Karst Fracture-cavity Reservoir in Tazhong Area

2011年塔中地区油气开发由台地边缘礁滩体转向台内鹰山组风化壳,由于油气主控因素、储层特征的改变,使第一批钻井失利较多;为了提高钻井成功率,高效开发塔中碳酸盐岩油气藏,塔里木油田公司与潜能恒信公司合作,在该地区展开了WEFOX叠前成像技术的应用。经过3年时间的攻关研究,使原来杂乱弱反射的碳酸盐内幕地层层位清晰可辨,并能准确反映鹰山组顶部削蚀不整合以及上奥陶统顶部不整合面,断层接触关系干脆,溶洞归位更加准确;高信噪比、高分辨率的资料为提高储层预测的精度,油气藏精细刻画提供了坚实的数据基础,并为水平井设计卡准油层层位提供了可靠依据,使得塔中地区碳酸盐岩缝洞油气藏钻井成功率逐年提高,由2011年的51%提高到2014的91%,2015年截至目前成功率为100%;充分体现了WEFOX叠前成像技术的优势。

In 2011,the oil and gas exploration and development in Tazhong area of Tarim Basin,has transformed from platform reefs to weathering crust of Yingshan Formation.Due to the change of the main-controlling factors and the reservoir characteristics,the first batch of wells had more failure.To increase drilling success ratio and efficiently develop carbonate reservoirs in Tazhong area,Sino Geo Cooperates with Tarim Oilfield Company to deploy the research of WEFOX pre-stack imaging technique.After three years study,random and weak reflection of carbonate internal stratigraphic horizon become clear;upper erosional unconformity of Yingshan Formation and unconformity surface of the Upper Ordovician can be accurately reflected;fault contact is clear;karst cave location becomes more accurate.High SNR and high resolution materials provide solid data bases for improving accuracy of reservoir forecast and precision of reservoir characterization,and sticking oil layer of horizontal wells,which increase drilling success ratio of carbonate fracture-cavity reservoir from 51% in 2012 to 91% in 2014,to 100% by now in 2015,and fully materialize the advantage of WEFOX.