Sedimentary facies and paleoenvironments of a gas-hydrate-bearing sediment core in the eastern Nankai Trough, Japan

Mechanical properties of hydrate-bearing turbidite reservoir in the first gas production test site of the Eastern Nankai Trough

“…Japan has promoted research and development of methane hydrate (MH) as a potential future energy resource (MH21, 2001). The sediments in the Eastern Nankai Trough, which is a promising location for hydrate exploration in Japan, are composed mainly of turbidites Ito et al, 2015;Komatsu et al, 2015). Hydrates occur in the pore spaces of sandy sediments in this turbidite reservoir.…”

Bulk sediment mineralogy of gas hydrate reservoir at the East Nankai offshore production test site

“…Seismic stratigraphy of this Ogasa turbidite system is subdivided into nine sequences from Og-a to Og-i in ascending order , among which sequence Og-b is defined as the gas hydrate reservoir sequence in the study area (Noguchi et al, 2011;Komatsu et al, 2015). The reservoir succession of sequence Og-b cored in 2012 comprises the lower (upward-fining sandy channel-fills: 1295e1316 mTVDss), middle (upward-coarsening alteration of sand and mud: 1274e1295 mTVDss), and upper sections (seal mud succession: 1260e1274 mTVDss) (Fujii et al, 2013;Komatsu et al, 2015). Previous core descriptions and particle size analysis for the METI test wells in 2004 have shown already that turbidites in the basin are commonly characterized by normally graded bedding, forming a Bouma sequence with dominance of very-fine-grained to fine-grained, moderately to poorly sorted sands (Suzuki et al, 2009).…”

Multiphase Flow Behavior of Layered Methane Hydrate Reservoir Induced by Gas Production

“…The Eastern Nankai Trough is the most potential resource-rich area of gas hydrates in Japan [22,27]. In this area, the total amount of CH 4 gas contained in HBS was estimated at an average value of 1.1 × 10 12 m 3 , most of which was reserved in the 16 methane hydrate concentrated zones (MHCZs) [4,22,28].…”

“…Table 1 presents the main modeling parameters and physical properties for the AT1 site sediments at the Eastern Nankai Trough. These were based on the geophysical well logs and core samples analyses from published papers [4,17,22,23,27,28]. The permeability and porosity are based on the logging data of AT1-MC and the pressure core data of AT1-C as shown in Figure 3.…”