北海道北部，幌延地域に分布する新第三紀堆積岩中の炭化水素ガスの分子組成と炭素同位体組成

概要

論文の詳細を見る
We conducted headspace gas analyses using cores from two 520 m boreholes to evaluate the gas permeability of Neogene sedimentary rocks in Horonobe, Hokkaido, Japan. Analytical data suggest that most hydrocarbon gases are microbial methane. Further analyses of these data indicated that the low concentration and heavy carbon isotope composition of methane could be explained by carbon isotopic fractionation during migration near fractures. The high residual volume of microbial methane observed in the study area suggests that the sedimentary layers have low gas permeability, and are affected less by secondary post-generation processes. The headspace gas analysis is an effective approach for detecting sedimentary layers having a high confinement capability.
東京地学協会の論文