Effects of mineral composition and pore structure in HC potential of reservoir rocks in the Western Foothill Belt, Taiwan

Abstract:

The exploration of unconventional gas resource achieved a successful breakthrough in USA due to the innovation of hydraulic fracturing and horizontal drilling since 1995. The production of shale gas dramatically changed the energy structure and released the demand of fossil fuel in USA. Many studies about the unconventional oil-gas resource were performed worldwide especially in China, which provide very useful characterization for unconventional gas reservoirs. Since Taiwan has a strong energy demand and still highly relied on imported fossil fuel, the development of unconventional gas resource needs to be concerned. Therefore, the objective of this study is to evaluate the potential of unconventional oil-gas in Taiwan. In this study, we examine mineral composition and pore structure of Miocene oil-gas bearing strata from the Western Foothill Belt in Taiwan. Sandstone samples were collected from Cholan Fm, Yutengpin ss, Kuantaoshan ss, Shangfuchi ss, Tungkeng Fm, Guanyinshang ss and Peiliao Fm; whereas shale samples were collected from Chinshui sh and Talu sh, as well as outcropped coal sample from Nanchung Fm. The porosity, permeability, TOC, thermal maturity, and mineral composition of samples are examined after a series of geochemical experiments. Finally, after comparing the data with their gas sorption capacity, the reservoir with the strongest potential in unconventional gas resource can be identified.