Characteristics and control mechanism of low resistivity contrast oil

Ordos Basin 3 Ze Bai*, Maojin Tan, Yujiang Shi, Gaoren Li, Simon Martin Clark 4 1. School of Geophysics and Information Technology of China University of 5 Geosciences, Beijing 100083, China. 6 2. School of Earth and Environment, Anhui University of Science & Technology, 7 Huainan 232001,China. 8 3. A Research Institute of Exploration and Development, PetroChina Changqing 9 Oilfield Company, Xi’an 710018, China. 10 4. Department of Earth and Planetary Sciences, Macquarie University, Sydney, 11 New South Wales 2109, Australia. 12 Correspondence and requests for materials should be addressed to Ze Bai 13 (email:baize@aust.edu.cn) 14 Abstract 15 The log interpretation and evaluation of Chang 8 tight sandstone reservoir in Longdong 16