Petroleum Science >2017, Issue 1: 1-23 DOI: https://doi.org/10.1007/s12182-016-0141-2
Fracture prediction in the tight-oil reservoirs of the Triassic Yanchang Formation in the Ordos Basin, northern China Open Access
文章信息
作者:Wen-Tao Zhao and Gui-Ting Hou
作者单位:
The Key Laboratory of Orogenic Belts and Crustal Evolution of Ministry of Education, School of Earth and Space Sciences, Peking University, Beijing 100871, China; China Huaneng Clean Energy Research Institute, Beijing 102209, China; PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, China;The Key Laboratory of Orogenic Belts and Crustal Evolution of Ministry of Education, School of Earth and Space Sciences, Peking University, Beijing 100871, China
投稿时间:2015-09-03
引用方式:Zhao, WT. & Hou, GT. Pet. Sci. (2017) 14: 1. https://doi.org/10.1007/s12182-016-0141-2
文章摘要
It is important to predict the fracture distribution in the tight reservoirs of the Ordos Basin because fracturing is very crucial for the reconstruction of the low-permeability reservoirs. Three-dimensional finite element models are used to predict the fracture orientation and distribution of the Triassic Yanchang Formation in the Longdong area, southern Ordos Basin. The numerical modeling is based on the distribution of sand bodies in the Chang 71 and 72 members, and the different forces that have been exerted along each boundary of the basin in the Late Mesozoic and the Cenozoic. The calculated results demonstrate that the fracture orientations in the Late Mesozoic and the Cenozoic are NW–EW and NNE–ENE, respectively. In this paper, the two-factor method is applied to analyze the distribution of fracture density. The distribution maps of predicted fracture density in the Chang 71 and 72 members are obtained, indicating that the tectonic movement in the Late Mesozoic has a greater influence on the fracture development than that in the Cenozoic. The average fracture densities in the Chang 71 and 72 members are similar, but there are differences in their distributions. Compared with other geological elements, the lithology and the layer thickness are the primary factors that control the stress distribution in the study area, which further determine the fracture distribution in the stable Ordos Basin. The predicted fracture density and the two-factor method can be utilized to guide future exploration in the tight-sand reservoirs.
关键词
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Ordos Basin · Yanchang Formation · Fracture prediction · Finite element modeling · Two-factor method · Tight-sand reservoirs