Abstract
Abstract The Zhangjiatan shale of the Southeastern Ordos Basin, which deposits in deep lake facies, has strong lithologic heterogeneity; it represents as shale, sandy laminae shale and thin sandstone. Shale with mm- to cm-scale sandy laminae is defined as Sandy Laminae Shale (SLS). However, the relationship between lithologic heterogeneity and hydrocarbon accumulation has never been studied. This study shows that lithologic heterogeneity, especially the occurrence of SLS will influence the accumulation of hydrocarbons within the shale system. SLS commonly has a larger pore size, higher porosity and better connectivity than thick and homogeneous shale. SLS commonly contains fewer residual hydrocarbons than homogeneous thick shale, indicating comparative ease in hydrocarbon expulsion. SLS commonly generates more bedding fractures. More fractures can be incurred when fracture extending into SLS. The occurrence of SLS can provide more storage spaces for fluids and gases, including oil, water, adsorbed gas, dissolved gas and free gas. SLS has been the pilot exploration and development target for shale hydrocarbon in the southeastern Ordos Basin. Homogeneous and thick shales, which have a large content of residual hydrocarbons, would be the targets for future exploration.
Highlights
The Zhangjiatan shale of the Southeastern Ordos Basin, which deposits in deep lake facies, has strong lithologic heterogeneity; it represents as shale, sandy laminae shale and thin sandstone
More fractures can be incurred when fracture extending into Sandy Laminae Shale (SLS)
As the lithologic heterogeneity is mainly caused by the development of sandy laminae in the southeastern part of the Ordos Basin, this study is focused on the sandy laminae of the Zhangjiatan shale deposited in the deep-lake environment (Figure 3)
Summary
Abstract: The Zhangjiatan shale of the Southeastern Ordos Basin, which deposits in deep lake facies, has strong lithologic heterogeneity; it represents as shale, sandy laminae shale and thin sandstone. SLS has been the pilot exploration and development target for shale hydrocarbon in the southeastern Ordos Basin. Sandy Laminae Shale (SLS) (shale with mm- to cm-scale sandy lamina) has been identified in deep-lacustrine mudstone depositional facies in many hydrocarbon prosperous basins in China (e.g., Ordos Basin, Qaidam Basin, Junggar Basin and Bohai Bay Basin) [3]. The Zhangjiatan shale is interpreted to have been deposited in a deep-lake environment and is laterally extensive and continuous, Zhangjiatan shale in the Southeastern Ordos Basin has strong lithologic heterogeneity, it
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
