2:45 PM - 3:00 PM
[MIS24-22] Characterization of grain-size distribution and mineral composition of hydrate-bearing sediments in the Nankai Trough
Using the gas hydrate-bearing sediments, the sedimentary features such as gain size and mineral composition were analyzed systematically. Based on this grain size distribution data, we categorized typical three kinds of standards samples: silty sand, sandy silt, and clayey silt, respectively. As a result of mineral composition analysis of sediment measured by X-ray diffraction (XRD), the bulk mineral compositions are characterized by 10 compositions, i.e., the quartz, hornblende, feldspars (orthoclase, Plagioclase), pyrite, smectite, kaolinite, calcium carbonate, chlorite, and mica. These mineral compositions are strongly correlated with grain size features such as median or means sizes. According to the above results, we prepared typical three kinds of standard samples, and measured pore-size distribution and permeability features using the nuclear magnetic resonance (NMR) method. In the presentation, we will compare with those physical features between standard samples and natural sediments from the eastern Nankai Trough.
This work was financially supported by the Research Consortium for Methane Hydrate Resources in Japan (MH21 Research Consortium) of the National Methane Hydrate Exploitation Program planned by the Ministry of Economy Trade and Industry (METI).