Estimation of Generated and Retained Gas Volume of the Besa River Formation in Liard Basin through 3-Dimensional Static Geochemical Modeling

Kwang Hyun Kim,Hyun Suk Lee,Andy Mort,Jiyoung Choi,Sung Kyung Hong,Kyungbook Lee,Andrew H Manning

doi:10.1155/2020/8859306

Abstract

The Besa River Formation mainly comprises argillaceous sediments, and the upper shale bed of the Formation has been considered as a prospective shale gas reservoir. The maturity and quantity of organic matter found in source rock are considered as factors for evaluating resource value. Original hydrogen index (HIo) and total organic carbon (TOCo) are considered as properties to estimate generated gas volume in shale gas reservoirs. Generally, TOCo and HIo are determined via geochemical analysis of organic matter and calculated from well-log data like density, sonic data, and resistivity. In this study, these properties were measured or calculated by using geological analysis data and bulk-density log, and then the prospective area from the geochemical perspective in Liard Basin is defined by realizing a 3-dimensional static geochemical model. To validate the static model, the gas-in-place (GIP) (496 Bcf/section) of the production well in this study area was compared with GIP (262 Bcf/section) in the static model. Expulsion efficiency was considered as 0.6. The result implies that this model has a method of informative assessment with regard to undeveloped shale gas resources. The static model provides spatial information for generated and retained gas volume in the Besa River Formation, Liard Basin.

Highlights

Shale resources in several unconventional fields such as Horn River, Montney, Cordova Embayment, and Liard in British Columbia have been developed or produced
This study shows the realized 3D distribution of estimated gas volume using geochemical data and well-log data in the Liard Basin
In this study, the expulsion efficiency is considered to accurately estimate the retained gas volume which is considered as the GIP in the static model; the efficiency was assumed as 0.6 [10]

Summary

Introduction

Shale resources in several unconventional fields such as Horn River, Montney, Cordova Embayment, and Liard in British Columbia have been developed or produced. Many researches have been evaluating shale gas reservoirs by using geochemical analysis and petroleum system modeling. The generative potential of shale gas resources can be estimated by initial geochemical properties such as the original hydrogen index (HIo) and original total organic carbon (TOCo) [9, 10]. For these reasons, the 3dimensional static geochemical model will be suggested by a method to define promising spots in the basin, such as Liard Basin, where there is not enough data for petroleum system modeling. Well-log data are used to estimate the generative potential based on the original geochemical data in the Besa River Formation, Liard Basin

Study Area and General Geology

Data and Methods

Results and Discussion

Conclusion