Expedition 370 summary

Online Access: Get full text
doi: 10.14379/iodp.proc.370.101.2017
Author(s): Heuer, Verena; Inagaki, Fumio; Morono, Yuki; Kubo, Yusuke; Maeda, Lena; Bowden, Stephen; Cramm, Margaret; Henkel, Susann; Hirose, Takehiro; Homola, Kira; Hoshino, Tatsuhiko; Ijiri, Akira; Imachi, Hiroyuki; Kamiya, Nana; Kaneko, Masanori; Lagostina, Lorenzo; Manners, Hayley; McClelland, Harry-Luke; Metcalfe, Kyle; Okutsu, Natsumi; Pan, Donald; Raudsepp, Maija Jocelyn; Sauvage, Justine; Schubotz, Florence; Spivack, Arthur; Tonai, Satoshi; Treude, Tina; Tsang, Man-Yin; Viehweger, Bernhard; Wang, David T.; Whitaker, Emily; Yamamoto, Yuzuru; Yang, Kiho; Kinoshita, Masataka
International Ocean Discovery Program, Expedition 370 Participants, College Station, TX
Author Affiliation(s): Primary:
University of Bremen, Center for Marine Environmental Sciences, Germany
Other:
Japan Agency for Marine-Earth Science & Technology, Japan
University of Aberdeen, United Kingdom
University of Calgary, Canada
Alfred Wegener Institute, Germany
Univesity of Rhode Island, United States
Nihon University, Japan
National Institute of Advanced Industrial Science and Technology, Japan
ETH Zürich, Switzerland
Plymouth University, United Kingdom
Washington University in Saint Louis, United States
California Institute of Technology, United States
University of Tokyo, Japan
University of Queensland, Australia
Kochi University, Japan
University of California-Los Angeles, United States
University of Toronto, Canada
Massachusetts Institute of Technology, United States
Texas A&M University, United States
Yonsei University, South Korea
Volume Title: Proceedings of the International Ocean Discovery Program; Temperature limit of the deep biosphere off Muroto; Expedition 370 of the riser drilling platform, Shimizu, Japan, to Kochi, Japan; Site C0023, 10 September-23 November 2016
Volume Author(s): Heuer, Verena; Inagaki, Fumio; Morono, Yuki; Kubo, Yusuke; Maeda, Lena; Bowden, Stephen; Cramm, Margaret; Henkel, Susann; Hirose, Takehiro; Homola, Kira; Hoshino, Tatsuhiko; Ijiri, Akira; Imachi, Hiroyuki; Kamiya, Nana; Kaneko, Masanori; Lagostina, Lorenzo; Manners, Hayley; McClelland, Harry-Luke; Metcalfe, Kyle; Okutsu, Natsumi; Pan, Donald; Raudsepp, Maija Jocelyn; Sauvage, Justine; Schubotz, Florence; Spivack, Arthur; Tonai, Satoshi; Treude, Tina; Tsang, Man-Yin; Viehweger, Bernhard; Wang, David T.; Whitaker, Emily; Yamamoto, Yuzuru; Yang, Kiho
Source: Proceedings of the International Ocean Discovery Program; Temperature limit of the deep biosphere off Muroto; Expedition 370 of the riser drilling platform, Shimizu, Japan, to Kochi, Japan; Site C0023, 10 September-23 November 2016, Verena Heuer, Fumio Inagaki, Yuki Morono, Yusuke Kubo, Lena Maeda, Stephen Bowden, Margaret Cramm, Susann Henkel, Takehiro Hirose, Kira Homola, Tatsuhiko Hoshino, Akira Ijiri, Hiroyuki Imachi, Nana Kamiya, Masanori Kaneko, Lorenzo Lagostina, Hayley Manners, Harry-Luke McClelland, Kyle Metcalfe, Natsumi Okutsu, Donald Pan, Maija Jocelyn Raudsepp, Justine Sauvage, Florence Schubotz, Arthur Spivack, Satoshi Tonai, Tina Treude, Man-Yin Tsang, Bernhard Viehweger, David T. Wang, Emily Whitaker, Yuzuru Yamamoto and Kiho Yang; International Ocean Discovery Program, Expedition 370 Participants, College Station, TX. Proceedings of the International Ocean Discovery Program, Expedition Reports, Vol.370, 20p. Publisher: International Ocean Discovery Program, Washington, DC, United States. ISSN: 2377-3189 CODEN: IDSDA6
Note: In English. 110 refs.; illus., incl. sects., 3 tables, sketch map
Summary: International Ocean Discovery Program (IODP) Expedition 370 explored the limits of the biosphere in the deep subseafloor where temperature exceeds the known temperature maximum of microbial life (∼120°C) at the sediment/basement interface ∼1.2 km below the seafloor. Site C0023 is located in the protothrust zone in the Nankai Trough off Cape Muroto at a water depth of 4776 m, in the vicinity of Ocean Drilling Program (ODP) Sites 808 and 1174. In 2000, ODP Leg 190 revealed the presence of microbial cells at Site 1174 to a depth of ∼600 meters below seafloor (mbsf), which corresponds to an estimated temperature of ∼70°C, and reliably identified a single zone of elevated cell concentrations just above the decollement at around 800 mbsf, where temperature presumably reached 90°C; no cell count data was reported for other sediment layers in the 70°-120°C range because the detection limit of manual cell counting for low-biomass samples was not low enough. With the establishment of Site C0023, we aimed to detect and investigate the presence or absence of life and biological processes at the biotic-abiotic transition utilizing unprecedented analytical sensitivity and precision. Expedition 370 was the first expedition dedicated to subseafloor microbiology that achieved time-critical processing and analyses of deep biosphere samples, conducting simultaneous shipboard and shore-based investigations. Our primary objective during Expedition 370 was to study the relationship between the deep subseafloor biosphere and temperature. We comprehensively studied the controls on biomass, activity, and diversity of microbial communities in a subseafloor environment where temperatures increase from ∼2°C at the seafloor to ∼120°C and thus likely encompasses the biotic-abiotic transition zone. This included investigating whether the supply of fluids containing thermogenic and/or geogenic nutrient and energy substrates may support subseafloor microbial communities in the Nankai accretionary complex. To address these primary scientific objectives and questions, we penetrated 1180 m and recovered 112 cores of sediment and across the sediment/basalt interface. More than 13,000 samples were collected, and selected samples were transferred to the Kochi Core Center by helicopter for simultaneous microbiological sampling and analysis in laboratories with a super-clean environment. In addition to microbiological measurements, we determined the geochemical, geophysical, and hydrogeological characteristics of the sediment and the underlying basement and installed a 13-thermistor sensor borehole temperature observatory into the borehole at Site C0023.
Year of Publication: 2017
Research Program: IODP Integrated Ocean Drilling Program
IODP2 International Ocean Discovery Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; 22 Environmental Geology; Asia; Authigenic minerals; Cenozoic; Chemostratigraphy; Communities; Cores; Deep biosphere; Ecology; Expedition 370; Far East; Geochemistry; Geomicrobiology; Geophysical methods; Geophysical profiles; Geophysical surveys; Heat flow; Hydrothermal conditions; IODP Site C0023; International Ocean Discovery Program; Japan; Kochi Japan; Lithostratigraphy; Magnetostratigraphy; Marine sediments; Microorganisms; Mineralization; Nankai Trough; North Pacific; Northwest Pacific; Pacific Ocean; Paleomagnetism; Physical properties; Quaternary; Sedimentary rocks; Sediments; Seismic methods; Seismic profiles; Shikoku; Surveys; Temperature; Tertiary; Thermophilic taxa; West Pacific
Coordinates: N322200 N322200 E1345759 E1345759
Record ID: 2019052565
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.