古土壤储层在胜利油区沙四段的发现

Discovery of caliche paleosol reservoir in Sha4 member in Shengli Oilfield

通过岩心观察、薄片鉴定、扫描电镜分析并与国外成功的经验相对比,首次在胜利油区沾化凹陷义东301井沙四段上亚段发现存在钙质古土壤高产油层。古土壤的识别标志主要包括钙结团块、肺泡结构、根模孔及钙化蛹等。沾化凹陷在沙四段上亚段沉积时期具备古土壤形成的气候条件和物质基础,古土壤储层的发现为进一步查明济阳坳陷在沙四段沉积末期存在沉积间断提供了重要依据。古土壤层还是优质储层,拓展了胜利油区储层勘探的领域。

Based on core observation,thin section analysis and examination of SEM,caliche paleosol reservoir was firstly discovered in well Yidong301 of Zhanhua Depression,which produced industrial oil fluid. The identification signs of caliche facies include calcified glaebules,alveolar structure,products of plant rooting and cocoons etc. During upper Sha4 member depositional stage,the climate condition and material foundation were favorable for forming caliche in Zhanhua Depression. The discovery of caliche facies can provide exposure evidence of later period of Sha4 member,and expand reservoir types in Shengli Oilfield.