正交偶极子声波测井在土库曼斯坦S气田测井评价中的应用

Application of WSTT to Reservoir Evaluation in Turkmenistan Gas Field S

土库曼斯坦S气田发育浅海相碳酸盐岩储层,储层发育致密,构造物性复杂,以高孔隙度低中渗透率为主。在进行测井评价过程中,由于S气田的特殊性以及常规和成像测井资料的局限性,难以精确有效地进行裂缝有效性判别、最大水平主应力方向判断以及流体性质识别。利用正交偶极声波(WSTT)测井资料进行各向异性分析得到地层应力方位。利用WSTT斯通利波能量衰减以及波形进行裂缝有效性判别,同时对S气田3个不同构造区块的地层最大主应力方向与有效张裂缝方向对比分析,判断裂缝的区域有效性,并用裂缝宽度进行验证。利用WSTT纵横波比和岩石机械参数曲线进行流体识别。WSTT测井资料在土库曼斯坦S气田碳酸盐岩储层测井评价中较好地弥补了常规和成像测井的不足,取得了满意的效果。

Shallow sea carbonate reservoir is developed in Turkmenistan gas field S. The reservoir is tight, and has a complex structure and physical property. S reservoir is mainly developed with high porosity and low-middle permeability. In log evaluation, it is difficult to efficiently carry out the fractures effectiveness evaluation, maximum horizontal stress direction judgment and fluid identification due to the special characteristics in gas field S and the limit of the conventional and image logs. WSTT is used to analyze the anisotropy so as to judge the formation stress direction; cross-dipole acoustic logging （WSTT） stoneley wave attenuation and waveform is used to evalu ate the fractures effectiveness, and the direction of the conductive fractures and the formation maximum stress in 3 different structure blocks are compared to evaluate the regional fractures ef- fectiveness, and this is verified by the fractures width. Combining with the rock and mechanic in dex curves, WSTT velocity ratio of compressional wave and shear wave is used to identify the fluid. WSTT makes up the weakness of conventional and image logs in Turkmenistan carbonate reservoir evaluation, and the log conclusion achieved is satisfied.