Log Evaluation Of Hydrocardon Bearing Shaly Sands In The Middle Of Sha 3 Member Of Block Xia-52 Of Linnan Oilfield

Generally, hydrocardon bearing shaly sands is a kind of hydrocardon bearing sands with higher shale content. The log interpretation and log evaluation of hydrocardon bearing shaly sands fall to doing two aspects. One is that hydrocardon bearing sands goes with low-resistivity, so analysis of low-resistivity origin is basic; the other is that conductive mechanism is so intricate that it's difficult to set up conductive model. Until now, there are over thirty kinds of the log interpretation models of water saturation, and, derived from them, there are about one hundred kinds of log interpretation model of water saturations, but all those models couldn't fit in with all of hydrocardon bearing shaly sands. Hence, the log interpretation and log evaluation of hydrocardon bearing shaly sands is always a nodus at home and abroad. The log interpretation theory and analysis method about water saturation of hydrocardon bearing shaly sands is derived from the pattern about water saturation of simple hydrocardon bearing sands, and furthermore derived from interpretation model of Formula Archie. The water saturation models of hydrocardon bearing shaly sands include Formula Dual Porosity, Formula Waxman-Smiths, Formula Dual Water, Formula Three Water, which is relatively in common use. Based on oil formation character of hydrocardon bearing shaly sands in the middle of Sha 3 Member of Block Xia-52 in Linnan Oilfield, the emphases of log interpretation and log evaluation of hydrocardon bearing shaly sands are to analyze of low-resistivity origin and select The water saturation models that hold true to the hydrocardon bearing shaly sands.In the middle of Sha 3 Member of Block Xia-52 in Linnan Oilfield, petroleum deposit has been exploited for many years. The structure of block possesses integrity and inheritance. The hydrocardon bearing sands belongs to powder-fine sandstone in the front of delta. The salinity of formation water is 30000～60000 ppm. In the block, there are two types of hydrocardon bearing sands, simple hydrocardon bearing sands and hydrocardon bearing shaly sands. And the former has mainly been exploited, while the latter has not mostly been exploited for many years. The reason is that the latter was interpretated as water sands in the log interpretation for its resistivity is lower. In addition, hydrocardon bearing shaly sands mostly has low permeability and is so easy to be polluted, which induce low off-take potentiality or no oil. However, hydrocardon bearing shaly sands certainly possesses productive potentiality. Hence, it's very important for Linnan Oilfield to find out hydrocardon bearing shaly sands unexploited, augment geologic reserve and keep production steady by newly log interpretation and log evaluation. In the middle of Sha 3 Member of Block Xia-52 in Linnan Oilfield, the hydrocardon bearing shaly sands give priority to powder sandstone, shaly powder sandstone. The shale content is higher and the amout of kaolinite predominates. The grading and rounding aremiddling or middling-different. Generally, the median of granularity is 50～170 micrometer. The porosity and permeability of hydrocardon bearing shaly sands is from mid to low. If porosity is middling or more than middling, the permeability of hydrocardon bearing shaly sands is close to the permeability of simple hydrocardon bearing sands. The irreducible water saturation of hydrocardon bearing shaly sands is averagely more nine percent than that of simple hydrocardon bearing sands. The hydrocardon bearing shaly sands is water wetting or strongly water wetting. The salinity of formation water is mid-high.In this research, main tasks lie in low-resistivity origin of hydrocardon bearing shaly sands, log interpretation of formation parameter, log evaluation and finding out what hydrocardon bearing shaly sands could be directly exploited without pressing crack or acidification. Among those, core technologies are low-resistivity origin of hydrocardon bearing shaly sands and log interpretation of water saturation.In the hydrocard...