Sedimentological and geological constraints on the habitability of microbes in subseafloor environment

• Project/Area Number: 25871219
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Geology; Environmental dynamic analysis
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: Uramoto Go-Ichiro 国立研究開発法人海洋研究開発機構, 高知コア研究所, 特別研究員(PD) (70612901)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2015: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2013: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
• Keywords: 海底堆積物 / 海底下微生物 / 微細構造 / 微小団塊

Outline of Final Research Achievements

This study established a modified resin-embedding method of marine sediments for high-resolution observation of sediment microstructure. The microfocus X-ray computed tomography (micro-XCT) and scanning electron microscopy (SEM) results showed significant microstructural disturbances were not observed in the samples prepared using the new resin-embedding method, and the microstructural arrangement of the sediment were clearly visible. In addition, the porosity visible from SEM images was similar to that measured using the moisture and density method, providing additional evidence that the microstructures were well preserved. The resin-embedding method allowed observation of the limited contact of the fine particles in clayey sediments and the presence of organic materials in environmental sediments. This method is suitable for the detailed observation and characterization of fine-grained marine sediment microstructure.

Research Products

• [Journal Article] Data report: diatom biostratigraphy of IODP Site U1371 in the South Pacific Ocean (2015)
  • Author(s): Itsuki Suto and Go-Ichiro Uramoto
  • Journal Title: Proceedings of the Integrated Ocean Drilling Program Volume: 329 Pages: 1-42
  • DOI: 10.2204/iodp.proc.329.203.2015
  • Peer Reviewed / Open Access
• [Journal Article] An improved sample preparation method for imaging microstructures of fine-grained marine sediment using microfocus X-ray computed tomography and scanning electron microscopy (2014)
  • Author(s): Go-Ichiro Uramoto, Yuki Morono, Katsuyuki Uematsu, Fumio Inagaki
  • Journal Title: Limnology and Oceanography: Methods Volume: 12 Issue: 7 Pages: 469-483
  • DOI: 10.4319/lom.2014.12.469
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Biological CO_2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system (2013)
  • Author(s): Ohtomo, Y., Ijiri, A., Ikegawa, Y., Tsutsumi, M., Imachi, H., Uramoto, G., Hoshino, T., Morono, Y., Sakai, S., Saito, Y., Tanikawa, W., Hirose, T., and Inagaki, F
  • Journal Title: Frontiers in Microbiology Volume: Article no. 361 Pages: 4-4
  • DOI: 10.3389/fmicb.2013.00361
  • Peer Reviewed / Open Access
• [Presentation] 南太平洋環流域の遠洋性粘土に存在する大量の微小マンガン粒について (2016)
  • Author(s): 浦本豪一郎, 諸野祐樹, 富岡尚敬, 和穎朗太, 上杉健太朗, 竹内晃久, 星野真人, 鈴木芳生， 光延 聖，菅 大暉, 宮本千尋，高橋嘉夫，稲垣史生
  • Organizer: 日本地球惑星科学連合2016年大会
  • Place of Presentation: 幕張メッセ（千葉県千葉市）
  • Year and Date: 2016-05-24
• [Presentation] An improved resin-embedding method for the observations of fine-grained sediment microstructures using micro-focus X-ray CT and SEM (2014)
  • Author(s): Uramoto, G.-I., Morono, Y., Uematsu, K., and Inagaki, F.
  • Organizer: 19th International Sedimentological Congress
  • Place of Presentation: Geneva, Switzerland
  • Year and Date: 2014-08-23
• [Presentation] Imaging of microbial cells in niches of marine sediment using in situ DNA and electron staining (2013)
  • Author(s): Go-Ichiro Uramoto, Yuki Morono, Katsuyuki Uematsu, Fumio Inagaki
  • Organizer: Japan Geoscience Union Meeting 2013
  • Place of Presentation: Makuhari Messe, Chiba