鄂尔多斯盆地大牛地气田盒2、3段沉积微相研究

Sedimentary microfacies of He2 and He3 Member in Daniudi gas field of Ordos basin

通过岩心观察,认为工区盒2、3段,不仅仅发育单一河流相沉积体系,而是发育一套辫状河三角洲-浅湖沉积体系。识别并划分了工区内沉积相、沉积亚相、沉积微相。另外,对工区特有沉积特点的研究,结合沉积过程和岩性特征,对重点沉积微相进一步划分为超微相。早二叠世,鄂尔多斯盆地克拉通沉积阶段,盆地内部坡度非常平缓的地形和北部蚀源区的抬升是形成大牛地气田辫状河三角洲-浅湖沉积体系的主要地质背景。

Based on core observation, it is thought that not only single fluvial facies sedimentary system but also a set of braid river delta-shallow lacustrine sedimentary system are developed in He2 and He3 Member. The sedimentary facies, subfacies and microfacies can be identified. In addition, according to the research on sedimentary characteristics, sedimentary process and lithology characteristics, the important microfacies are divided into ultra-microfacies. In lower Permian, the Craton depositional period of Ordos basin, the flat landform in the basin and the lifting of the north provenance are the main geological environment for the formation of braid river delta-shallow lacustrine sedimentary system in Daniudi gasfield.