Hot fluids, burial metamorphism and thermal histories in the underthrust sediments at IODP 370 site C0023, Nankai Accretionary Complex

• DOI: 10.1016/j.marpetgeo.2019.104080
• Publication Date: 2019-10-12T00:03:35Z
• Authors: Man-Yin Tsang; Stephen A. Bowden; Zhibin Wang; Abdalla Mohammed; Satoshi Tonai; David Muirhead; Kiho Yang; Yuzuru Yamamoto; Nana Kamiya; Natsumi Okutsu; Takehiro Hirose; Myriam Kars; Florence Schubotz; Akira Ijiri; Yasuhiro Yamada; Yusuke Kubo; Yuki Morono; Fumio Inagaki; Verena B. Heuer; Kai-Uwe Hinrichs
• Keywords: SOLUBILITIES; International Ocean Discovery Program; Supplementary Data; FLOW; Stratigraphy; NE/P015182/1; Oceanography; 551; 530; 01 natural sciences; PARAMETERS; BASINS; 5000-BAR; QE; SYSTEM H2O-NACL; 14. Life underwater; 1000-DEGREES-C; 0-X-NACL; 0105 earth and related environmental sciences; hot fluids; 0-DEGREES-C; Natural Environment Research Council (NERC); biomarkers; Geology; hydrothermal mineralization; MODEL; QE Geology; fluid inclusions; Geophysics; 13. Climate action; IODP 370 temperature limits; Economic Geology

Drilling during International Ocean Discovery Program (IODP) Expedition 370 at Site C0023 encountered instances of hydrothermal mineralization from 775 to 1121 m below seafloor. Fluid inclusion homogenization temperatures measured on barite veins within this interval indicate precipitation fluids with up 220 °C, and salinities ten times higher than interstitial water (16–25 c.f. 2.8–3.6 wt % NaCl). Patches stratabound (rhodochrosite, calcite, anhydride) are largely confined the vicinity have vertical thicknesses extents that can be explained by thermal aureoles veins. Thermal maturities petroleum biomarkers in underthrust sediments record a rise pre-oil window early oil maturities. Basin models show increases maturity burial metamorphism, kinetic-based calculations suggest hot would only had minimal effect hydrocarbon generation. However, movement still has geochemical implications creates complex history where both short-duration, localized heating fracture zones (~200 °C for less 1 yr) over long durations (80–110 0.5–2 Myrs) need considered.