Determination of Shale Volume and Distribution Patterns and Effective Porosity from Well Log Data Based On Cross-Plot Approach for A Shaly Carbonate Gas Reservoir

World Multidisciplinary Earth Sciences Symposium 2016

Moradi, Siyamak^1 ; Moeini, Mohammad^1 ; Ghassem Al-Askari, Mohammad Kamal^2 ; Mahvelati, Elaheh Hamed^1

Abadan Faculty of Petroleum Engineering, Petroleum University of Technology, Abadan, Iran^1

Ahwaz Faculty of Petroleum Engineering, Petroleum University of Technology, Ahwaz, Iran^2

关键词: Distribution patterns;    Effective porosity;    Formation evaluation;    Gas reservoir;    Neutron density;    Petrophysical parameters;    Productivity of gas wells;    Well log data;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/44/4/042002/pdf
DOI  :  10.1088/1755-1315/44/4/042002

来源: IOP

【 摘 要 】

Determination of shale volume distribution is one of the most important factors that has to be considered in formation evaluation, since existence of shale reduces effective porosity and permeability of the reservoir. In this paper, shale volume and distribution (dispersed, laminar and structural) and formation effective porosity are estimated from well log data and cross-plots. Results show that distribution of shale is mainly dispersed with few of laminar ones, and the quality of reservoir (effective porosity) decreases with depth resulting in low productivity of gas wells drilled in lower zones. Good agreement of estimated shale volumes and effective porosities from neutron-density cross-plot with the values determined from gamma ray log (CGR) and core analysis demonstrates the accuracy and applicability of these plots in determination of petrophysical parameters from conventional log data.