Petrophysical properties and their relation to injected CO2 behavior in a reservoir at the Nagaoka pilot site, Japan

Abstract A saline aquifer of the early Pleistocene Haizume Formation was used for CO 2 storage pilot test at Nagaoka site, Japan. The lithological and petrophysical features such as grain-size and pore-throat size distributions are presented by sediment core analysis. The aquifer is interpreted as deltaic deposits and the CO 2 injection part corresponds to the high stand systems tract in terms of the sequence stratigraphic framework. The vertical heterogeneity of CO 2 injectivity is related to the lithological features such as grain size and pore-throat size distributions. The detailed core analysis can be a promising technique for reservoir assessment such as CO 2 injectivity potential, not only applicable to the Nagaoka site but also to other sites.