Research of Reservoir Sedimentary Microfacies of Lower Member Es2 in Shanghe Oilfield

To decipher the origin of the lower member Es2 at Shahejie Formation in Shanghe area deposits is significant for tracing the distribution of source rocks and interpreting the evolution of depositional environment. The origin of the study area remains a puzzle for long with its evidence of distribution of sedimentary microfacies. This paper showed a typical river delta sedimentary type composed of massive packsand and mudstone by using core observation and well logging experiments, including three subfacies delta front, shallow lake shore and half deep lake. Depositional model was also established to reflect regional distribution and source direction of the target zone. On the other hand, delta front could be subdivided into several sedimtentary type, such as submarine distributary channel, frith dam, far sand dam and sheet sand separated by distributary gulf according to lithologic characteristics, tectonic and geophysics features, which raises the importance of the investigations on the sedimentary characteristics, the provenance and their relationship with the oil potential.