南堡油田浅层低对比度油层识别方法研究

Study on Identification Methods of Shallow Low-contrast Reservoir in Nanpu Oilfield

由于油藏的沉积环境复杂、油藏构造幅度低、高束缚水饱和度和黏土矿物附加导电性等多个因素的综合影响,南堡油田浅层油藏存在大量低对比度油层及油水同层。通过对36个典型低对比度油层和水层敏感参数的系统研究,提出了5种具有典型意义的低对比度油层识别方法:(1) R_(wa)(R_t)/R_(wa)(△SP)-V_(sh)交会图版法;(2)测井曲线敏感识图法;(3)自然电位幅度差异识别法;(4)基于钙质校正的碳氧比测井法;(5)常规动静态资料综合识别方法。通过矿场实践,南堡油田大量低对比度油层被识别出来并获得工业油流,在低对比度油层的解释中取得了较好的应用效果。

Due to the combined influence of many factors in the reservoir,such as complex sedimentary environment,low amplitude structure,high irreducible water saturation and additional conductivity of clay mineral,there are a lot of low-contrast oil layers and oil-water layers in shallow reservoirs of Nanpu Oilfield.Based on the systematic study of the sensitive parameters of 36 typical low-contrast oil layers and water layers,5 typical identification methods for low-contrast oil layers have been proposed:(1)Rwa(Rt)/Rwa(ΔSP)-Vsh intersection pattern method;(2)logging curve sensitivity diagram method;(3)amplitude difference recognition method of natural potential;(4)carbon-oxygen ratio logging method based on calcareous content correction;(5)comprehensive identification method of conventional dynamic and static data.Through the practice of the field,a large number of low-contrast oil layers in Nanpu Oilfield have been identified and obtained industrial oil flow,and good application results have been achieved in the interpretation of low-contrast oil layers.