泥页岩储层测井沉积学分析——以泌阳凹陷泌页HF-1井核桃园组为例

Logging Sedimentology Analysis of Shale Reservoir: A Case Study of Biye HF-1 Well of Hetaoyuan Formation in Biyang Depression

【目的】以泌阳凹陷泌页HF-1井核桃园组页岩油储层为研究对象,分析泥页岩地层测井的沉积学。【方法】通过改进的Δlog R方法,建立适合研究区泥页岩有机质含量的测井计算公式;根据计算的有机质含量,结合矿物组分含量及自然伽马能谱测井特征,分析沉积环境变化。【结果与结论】利用测井资料计算泌阳凹陷泌页HF-1井核桃园组泥页岩地层中的TOC,取得较好的效果,计算公式可在本研究区其他未取岩心的井中推广应用。泌页HF-1井核桃园组2 390~2 465 m地层由底部到顶部其沉积环境变化:湿润多雨的气候条件下基本一直处于还原环境,但是随着湖水深度逐渐变浅以及陆源物质输入的增加,地层中有机碳含量逐渐减少;其中2 432~2 461 m地层为深水还原环境,陆源物质输入较少,有利于有机质的堆积和保存,是最有利的页岩油储层赋存潜力段。

【Objective】Taking the shale oil reservoir as the research object in Hetaoyuan Formation of BYHF-1 well in Biyang Depression, the sedimentary environment characteristics of shale formation are analyzed by logging data.【Method】Based on the improved Δlog R method, a logging calculation formula suitable for shale organic matter content(TOC) is established in the study area.According to the calculated TOC, combined with the mineral component contents and natural gamma ray spectrometry logging characteristics, the changes of sedimentary environment are analyzed.【Result and Conclusion】Good results are obtained for the calculation of TOC by using logging data in the mudstone shale formation of Hetaoyuan Formation of BYHF-1 well in Biyang Depression.The calculation formula can be applied in other wells without cores in this research area.It is found that the sedimentary environment is basically reducing environment in humid and rainy climates at the section of 2 390-2 465 m Hetaoyuan formation in the BYHF-1 well.As the depth of lake water decreases and the terrigenous input increases, the organic carbon content also drops from bottom to top of studied formation.The formation at depth of 2 432 – 2 461 m is the most favorable potential member of shale oil reservoir, since it sedimented in deep water reduction environment with a decreasing terrigenous input, which facilitates the concentration and preservation of the organic materials.