Application of mathematical statistics to shale gas-bearing property evaluation and main controlling factor analysis

Abstract

Gas-bearing property evaluation and main controlling factor analysis have remained a concern in shale gas research. The application of principal component analysis, an important mathematical statistical method, in gas-bearing property evaluation and main controlling factor analysis of the Longmaxi shale in the Weirong area, Sichuan Basin, was examined. The Longmaxi shale exhibits high heterogeneity, manifested in the organic matter abundance, mineral composition, and pore structure. Seven geological factors, including the temperature, pressure, TOC content, clay content, brittle mineral content, pore volume, and specific surface area (SSA), were selected in principal component analysis. Four principal components with geological significance, such as mineral composition, formation condition, pore structure, and organic matter abundance, were extracted through principal component analysis, and further constituted a comprehensive factor. Shale gas-bearing properties were evaluated according to the score of the comprehensive factor. The Longmaxi shale could be identified as exhibiting good, medium, and poor gas-bearing properties based on the comprehensive factor scores of these samples. According to each geological factor’s contribution to the comprehensive factor, combined with geological analysis, it could be considered that gas-bearing properties are primarily controlled by pore volume, SSA, and clay content, followed by TOC content, brittle mineral content, temperature and pressure.

Conditions for the open pores formation in medical textile materials for the treatment of wounds using iron oxide nanopowders

“…Processing of these pore formation processes is carried out by the methods of mathematical statistics [25] and mathematical modelling [26].…”

Assessing heterogeneous groundwater systems: Geostatistical interpretation of well logging data for estimating essential hydrogeological parameters

“…Several works on using factor analysis for the interpretation of well logs data are reported in the literature 38 , 39 . For instance, Li et al 40 applied factor analysis for the characterization of gas-bearing formation in Sichuan Basin, China, and proved its efficiency in formation evaluation compared to the other conventional methods. A study conducted by Asfahani 41 indicated the effectiveness of factor analysis for lithology identification.…”