东濮凹陷低电阻率油层显示特征及成因

Reservoir displaying features and genesis for low resistivity oil zones of Dongpu sag

国内大部分油田已进入高含水开发期,寻找低电阻率油气层在内的隐蔽性油气藏是增储上产的一种有效途径。以东濮凹陷低电阻率油层为例,针对低电阻率油层的显示特征进行了较为详细的探讨,从黏土矿物含量、孔喉半径和微孔隙发育、岩石润湿性等方面进行了成因分析,指出岩石骨架颗粒粒径小、泥质含量偏重、地层水矿化度高、油藏高度低是形成东濮凹陷低电阻率油层的主要原因,高矿化度钻井液侵入和含导电矿物的影响也是值得重视的因素。该研究对现场录井解释评价低电阻率油层具有一定的借鉴作用。

Most domestic oilfields have entered the high aquifer-developing period, seeking for concealed oil and gas zones with low resistivity is an effect way to increase production. Take an example of the low resistivity oil zones in Dongpu Sag of Zhongyuan Oilfield, the paper discussed the displaying features according to the low resistivity oil zones. From the aspects of clay mineral content, pore throat radius, micro pore development and rock wetness, the genetic analysis was carried out, the author pointed out that the rock matrix with small grain sizes, heavier clay content, higher formation water salinity and lower reservoir height were the main reasons for forming the low resistivity oil zones in Dongpu Sag, and the affects of the influx of high salinity drilling fluid and conductive mineral bearing were also the valuable factors. The above analysis has certain reference functions for low resistivity oil zone interpretation and evaluation on wellsite.