Oil & Gas Geology ›› 2025, Vol. 46 ›› Issue (2): 567-574.doi: 10.11743/ogg20250215

• Methods and Technologies • Previous Articles     Next Articles

A deep learning-based model for predicting porosity of ultradeep fractured-vuggy hydrocarbon reservoirs

Zhijiang KANG1,2(), Ziyan DENG3(), Fan YANG1,2, Dongsheng ZHOU3   

  1. 1.Petroleum Exploration and Production Research Institute,SINOPEC,Beijing 102206,China
    2.State Energy Key Laboratory for Carbonate Oil and Gas,Beijing 102206,China
    3.China University of Geosciences (Beijing),Beijing 100083,China
  • Received:2024-10-20 Revised:2025-01-02 Online:2025-04-30 Published:2025-04-27
  • Contact: Ziyan DENG E-mail:kangzj.syky@sinopec.com;2111210013@email.cugb.edu.cn

Abstract:

Constructing a porosity prediction model for ultradeep fractured-vuggy hydrocarbon reservoirs holds great significance for their exploration and exploitation. These reservoirs, with burial depths exceeding 7 500 m, exhibit relatively low signal-to-noise ratios (SNRs) and extremely significant heterogeneity in fractures and vugs. These factors lead to major deviations between the porosity predicted using seismic wave impedance-based models and well log interpretation results for fractured-vuggy reservoirs. In this study, we propose a deep learning-based model for predicting the reservoir porosity involving the nonlinear relationships among multiple seismic attributes. Specifically, eight seismic attributes related to reservoir porosity are selected to construct a seismic attribute training set that matches log-derived porosity. Then, the skewed distribution of seismic attributes in the training set is corrected using the Box-Cox transformation, and then optimized with the seismic facies-constrained deep learning model as well as the Bayesian algorithms. A mathematical model is thereby established illustrating the nonlinear relationships between multiple seismic attributes and reservoir porosity. Compared to the commonly used seismic wave impedance-based prediction model, the newly proposed model can increase the goodness of fit of validation wells from 24 % to 92 %, substantially enhancing the prediction accuracy.

Key words: deep learning, porosity, carbonate rock, ultradeep oil and gas, fractured-vuggy hydrocarbon reservoir

CLC Number: