牛庄洼陷沙三下—沙四上泥页岩特征及沉积环境

为了明确非常规油气藏中不同泥页岩岩石类型与沉积环境的关系,针对不同泥页岩特征及沉积成因问题,通过岩心观察,利用岩矿薄片、扫描电镜、显微荧光以及元素分析等分析化验手段,开展了牛庄洼陷沙三下—沙四上泥页岩沉积环境分析及其与泥页岩岩相类型的对应关系研究.结果表明:牛庄洼陷沙三下—沙四上泥页岩共发育纹层状泥质灰岩、纹层状灰质泥...

Characteristics and sedimentary environment of shale in the lower part of Sha3 and upper part of Sha4 in Niuzhuang subsag

In order to clarify the relationship between different shale rock types and sedimentary environment in unconventional oil and gas reservoirs,according to different shale rock types and petrological characteristics,through core observation,rock ore flakes,scanning electron microscopy,microfluorescence and element analysis,etc.The sedimentary environment of shales in the lower part of Sha3 and upper part of Sha4 in Niuzhuang subsag was analyzed and the corresponding relationship with the types of shales was studied.The results show that the shales in the lower part of Sha3 and upper part of Sha4 in Niuzhuang subsag can be divided into six main rock types:laminar argillaceous limestone,laminar calcareous mudstone,bedded calcareous mudstone,bedded mudstone,massive mudstone and massive sandy mudstone.The first four types have good reservoir property and oil bearing.The palaeoclimate changed from dryness to warm and wet,the palaeowater depth changed from deep to shallow,and the saltwater environment changed to fresh water environment.Laminated sedimentary structures are more likely to form in the sedimentary environment with relatively deep water and argillaceous limestone or calcareous mudstone is more likely to form in the salty water environment with relatively highpaleosalinity.The above results have certain guiding significance for unconventional oil and gas exploration.