基于成像测井的塔河油田奥陶系鹰山组中深层碳酸盐岩优质储集层预测

Well logging prediction of high quality reservoirs in medium-deep carbonate rocks of Ordovician Yingshan Formation in Tahe Oilfiled based on imaging logging

塔里木盆地塔河油田奥陶系鹰山组中深层碳酸盐岩储集层具备良好的勘探潜力,自2014年塔深3井突破以来,鹰山组碳酸盐岩储集层已累计产出石油超过1亿吨.但该储集层具有时代老,埋藏深,成岩和构造演化复杂等特征,亟需在揭示储集层成因基础上,建立不同类型碳酸盐岩储集层配套测井评价方法.本文通过岩心、薄片观察,结合常规和成像测井从碳酸盐岩储集层储集空间类型出发,识别并划分出溶孔型、裂缝型、裂缝-孔洞型和洞穴型4种碳酸盐岩储集层类型,总结不同类型碳酸盐岩储集层发育特征.通过岩心刻度常规和成像测井建立不同类型碳酸盐岩储集层测井响应特征图版,并进一步实现了单井储集层类型的测井识别和划分,从而在储集层类型的约束下实现单井碳酸盐岩储集层综合评价以及有利发育区带预测.研究认为“裂缝-孔洞型”和“洞穴型”储集层发育高角度溶蚀扩大缝、断层破碎带空腔、溶蚀孔洞及洞穴,可形成有利储集体发育的碳酸盐岩缝洞系统.研究成果可为塔河油田奥陶系鹰山组中深层碳酸盐岩有利储集层分布与预测提供理论指导和技术支撑.

The Ordovician Yingshan Formation medium-deep carbonate rock field in Tahe Oilfield has good exploration potential.Since the breakthrough of Tashen 3 well in 2014,more than 1 billion tons of oil have been produced in Yingshan formation.However,the carbonate reservoir has the characteristics of old age,deep burial,complex diagenesis and structural evolution.It is urgent to establish logging evaluation methods for different types of carbonate reservoirs based on revealing the genesis of the reservoir.Through core and thin section observation,combined with conventional and imaging logging,this paper identifies four types of carbonate reservoirs from the type of reservoir space:dissolution pore,fracture,fracture-hole and cave.By core calibrating conventional and imaging logging,the logging response characteristic plates of different types of carbonate reservoirs are established respectively.Then the logging identification and categorization of reservoir types are further realized in single well.Finally,the comprehensive evaluation of single well carbonate reservoir and the prediction of favorable development zones are accomplished on the basis of the constraints of reservoir types.High angle dissolution expansion fractures,fault fracture zones and dissolution caves are developed in fracture-hole and cave reservoirs respectively,which can form fracture-cave systems beneficial to the development of reservoirs.The research results can provide theorical guidance and technical basis for the distribution prediction of high quality reservoirs in the medium-deep layers of Tahe oilfield.