基于自然电位计算泥质砂岩储层孔隙度的方法

阿根廷EH油田目的层段为泥质砂岩储层,泥质的分布形式为分散泥质。研究区内绝大多数井所采用的测井系列仅有自然电位、冲洗带电阻率和深感应电阻率3条曲线,缺乏孔隙度测井系列,应用传统技术手段只能实现测井资料的定性评价,有限的测井资料给孔隙度等储层参数的计算带来了很大困难。采用交会图技术优选出自然电位曲线和埋藏深度作为孔隙度的敏感曲线,提出利用校正自然电位计算的泥质含量和埋藏深度定量计算孔隙度的新方法,通过声波时差孔隙度和阿尔奇公式反演的孔隙度检验,证明了该泥质砂岩储层计算孔隙度方法的可靠性。

Calculation Method of Shale Sandstone Reservoir Porosity Based on SP Log

The layers of Argentina EH oilfield are sandstone reservoirs, the distribution form of shale is dispersed shale.The log data of most wells contain only SP, flushed zone resistivity and deep induction resistivity in the studied fields without logging porosity data.If we use the conventional interpretation techniques, we can only achieve the qualitative evaluation of log data, in these cases, it is very difficult to calculate the porosity and other reservoir parameters.In this article, we can determine the most optimal sensitivity curves for porosity with the crossplot technique, which contains SP and buried depth.Finally, a new method is provided for calculating reservoir porosity which is based on shale content and buried depth, so the shale content is calculated by corrected SP curves.Porosity-calculated from acoustic and porosity-calculated from Archie formula are tested, which proves the calculation method of shale sandstone reservoir porosity is reliable.