渤海湾海水泥浆侵入油气层双侧向测井定量分析研究

Quantitative Study of Dual Laterolog Response to Oil/Gas Formation Invaded by High Salinity Mud Filtrate in Bohai Gulf.

欧阳健，张建华，等．渤海湾海水泥浆侵入油气层双侧向测井定量分析研究．测井技术，１９９８，２２（４）：２５６～２６０泥浆滤液侵入油气层是一个复杂的物理过程，对海水泥浆浸泡含低矿化度地层水的油层的侧向测井响应进行了数值模拟与研究。结果证明：使侧向测井响应降低的因素除了泥浆性能与浸泡时间外，还和饱和度、渗透率、原油粘度等有关。若一般性能的泥浆浸泡高孔、高渗油层达８～１０ｄ以上，深侧向测井可降到原始油层电阻率的１／３～１／２，它不仅影响电测井定量计算饱和度，也影响测井识别油气层。因此，无论识别油气层或水层，或是定量分析原状地层电阻率进而求准饱和度，都需考虑泥浆滤液侵入油气层对电测井响应的影响。

It is a complicated physical process for mud filtrate to invade oil and gas zone. Laterolog responses to oil bearing formation with low salinity formation water invaded by high salinity mud filtrate are simulated numerically and studied. The result indicates that the decreasing of laterolog response is affected by the property of mud, invasion time, saturation, permeability, oil viscosity and so on. If an oil bearing zone with high porosity and high permeability is invaded by ordinary mud for 8—10 days, the deep laterolog readings reduce to 1/3—1/2 of the true formation resistivity. It affects not only the quantitative calculation of saturation, but also the identification of oil/gas zone. Therefore, as to oil/gas zone and water zone evaluation or true formation resistivity and saturation determination, we must consider the influence of mud filtrate invasion on the resistivity logging responses.