Skip to main content

ORIGINAL RESEARCH article

Front. Earth Sci.
Sec. Solid Earth Geophysics
Volume 12 - 2024 | doi: 10.3389/feart.2024.1484021
This article is part of the Research Topic Experimental and Numerical Simulations of Rock Physics View all 5 articles

A method for calculating saturation in tight sandstone reservoirs based on the dual porosity model

Provisionally accepted
Yi Xin Yi Xin 1,2,3Wei Duan Wei Duan 4Chuang Han Chuang Han 1,2,3Kang Bie Kang Bie 1,2,3Xinjian Zhao Xinjian Zhao 1,2,3Yong Ai Yong Ai 1,2,3Peiqiang Zhao Peiqiang Zhao 5,6*
  • 1 Tarim Oilfield Company, PetroChina, Koral, China
  • 2 R&D Center for Ultra-deep Complex Reservoir Exploration and Development,CNPC, Koral, China
  • 3 Engineering Research Center for Ultra-deep Complex Reservoir Exploration and Development, Xijing Uygur Autonomous Region, Korla, China
  • 4 Beijing Key Laboratory of Earth Prospecting and Information Technology, China University of Petroleum, Bejing, China
  • 5 China University of Petroleum, Beijing, Beijing, China
  • 6 Beijing Key Laboratory of Earth Prospecting and Information Technology, China University of Petroleum, Beijing, China

The final, formatted version of the article will be published soon.

    With the continuous development of exploration and development, tight sandstone reservoirs have become an essential field of oil and gas exploration. The tight sandstone reservoirs are characterized by complex lithology, poor pore structure, and strong heterogeneity, which bring great difficulties to formation evaluation by well logs.Especially, the accuracy of the Archie formula for calculating the water saturation of tight sandstone reservoirs containing fractures is not high, saturation evaluation faces greater challenges. Therefore, how to calculate the saturation of tight sandstone reservoirs more accurately is an urgent problem to be solved. In this paper, the tight sandstone reservoirs of the Jurassic Ahe Formation in the Tarim Basin were taken as the research area. a saturation model that combines the effects of shale and fractures was proposed. Specifically, if the shale content is more than 20 %, the Indonesian formula is used to calculate the saturation. If the shale content is less than 20 %, the dual porosity model is adopted. Based on the rock resistivity and nuclear magnetic resonance (NMR) experiment results, the porosity and T2 logarithmic mean values are selected as influencing factors to calculate the key parameters of the dual porosity model. The saturation of tight sandstone reservoirs in the Jurassic Ahe Formation of the Tarim Basin is calculated through the method proposed in this paper. The case study shows that the accuracy of the proposed method is higher than that of the Archie model.The method proposed in this paper demonstrates excellent adaptability in the quantitative evaluation of saturation for tight sandstone reservoirs.

    Keywords: Tight sandstone, dual porosity model, Resistivity logs, Water saturation calculation, Rock resistivity experiment, Nuclear magnetic resonance (NMR) experiment

    Received: 21 Aug 2024; Accepted: 07 Oct 2024.

    Copyright: © 2024 Xin, Duan, Han, Bie, Zhao, Ai and Zhao. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

    * Correspondence: Peiqiang Zhao, China University of Petroleum, Beijing, Beijing, China

    Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.