伊拉克北部K油田碳酸盐岩储层电成像测井评价

APPLICATION OF ELECTRICAL IMAGING WELL LOGGING IN EVALUATION OF THE CARBONATE RESERVOIRS IN K OILFIELD IN NORTH IRAQI

K油田位于伊拉克北部库尔德地区，该油田发育白垩系浅海相碳酸盐岩储层，岩性主要为灰岩、白云岩以及之间的过渡类型。由于K油田碳酸盐岩储层非均质性严重，储集空间类型复杂，岩性多样化，裂缝多期发育，次生孔隙发育，仅仅依靠常规测井曲线已无法完成储层测井评价。本文利用电成像（XRMI）测井技术分辨率高、携带大量地质信息的优势，首先对K油田储层岩性进行精细解释，并识别出裂缝和孔洞。其次，利用测井解释系统定量分析电成像测井资料，得到了裂缝参数和孔洞参数，并将储层划分为裂缝孔洞型储层。最后，多口井的成像测井资料地应力综合分析结果表明，利用椭圆井眼和诱导缝计算的水平最大主应力方向一致，K油田白垩系储层的水平最大地应力方向主要为N—S向。实践证明，成像测井在伊拉克K油田碳酸盐岩储层评价中发挥了重要的作用。

K oilfield lies in Kurds area of north iraqi where carbonate reservoirs of Cretaceous shallow-sea facies develop and the lithology is mostly limestone,dolomite and transitional type.Due to strong heterogeneity,complicated reservoir type,diversified lithology,multi-age developed fracture and induced porosity in the carbonate reservoirs of K oilfield,conventional logs can not be only relied on in well logging evaluation. Electrical imaging(XRMI) well logging technology which has high resolution and lots of geologic information is used to interpret the lithology and identify fractures and rugs in K oilfield.Secondly,the logging interpretation system analyzes the electrical imaging logging data quantitatively to get fracture and rug parameters and divides reservoirs into fracture and vug type.Finally,comprehensive analysis of the ground stress with the imaging well logging data of several wells shows that the level maximum principal stress directions calculated with ellipse hole and induced fractures are correspond with each other.The ground stress direction of Cretaceous reservoirs in K oilfield is N-S. Practice proved that imaging well logging played an important role in carbonate reservoir evaluation in K oilfield of Iraqi.