演武油田长3油层段优质储层特征及预测

探讨鄂尔多斯盆地演武油田长3油层段相对优质储层富集规律,为同类型油藏勘探开发提供借鉴。从研究区长3油层段砂岩储层的沉积背景、成岩作用和微观特征入手,运用古地貌恢复等方法,对古地貌单元中邻近不整合面的斜坡和残丘带的储层发育特征进行了重点研究。结果表明研究区延长组古暴露面上发生的下渗大气水对不整合面之下储层进行的溶蚀改造最为强烈,是形成相对优质储层的关键因素,有利于油气充注成藏。古地貌单元中的斜坡和残丘带是优质储层的勘探评价有利区带。

Characteristics of high-quality reservoir and prediction of Chang-3 oil section in Yanwu Oilfield,Ordos Basin,China

The accumulation regularity of high quality reservoir of Chang-3 Member of Upper Triassic Yanchang Formation is discussed so as to provide data for the exploration of similar type of oil pool.Focus is put on the study of reservoir development characters of the palaeo-geomorphology,especially on the slope adjacent to the unconformity plane and hills,by using the method of recovery of ancient topography.It shows that the corrosion by infiltration meteoric water to the Yanchang Formation reservoir under the unconformity plane is strong,and it is the key factor to the formation of high-quality reservoir and favorable for the charging and accumulation of oil and gas.Therefore,the slope and hills of the ancient topography are the favorable areas for evaluation and exploration of high-quality reservoir.