Project Details
Projekt
Molecular-isotopic studies of microbial processes and organic matter in the subseafloor coalbed biosphere of Shimokita (IODP Exp. 337)
Applicant
Professor Dr. Kai-Uwe Hinrichs
Subject Area
Palaeontology
Term
from 2012 to 2016
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 224625601
This proposal seeks continued support for post-cruise research related to IODP Expedition 337 (July 26 to September 30, 2012), in which Prof. Dr. Kai-Uwe Hinrichs (proponent) and his co-workers Drs. Verena Heuer, Yu-Shih Lin, and Marshall Bowles participated as co-chief scientist and shipboard scientists, respectively. IODP Exp. 337 was the first scientific ocean drilling initiative to core and sample a subseafloor hydrocarbon system using riser-drilling technology. Hole C0020A was drilled at a water depth of 1180 m and reached a total sediment depth of 2466 m. It is currently the deepest hole that was drilled by scientific ocean drilling. The expedition seeks to explore the microbial ecosystem and microbial processes associated with a deeply buried coalbed situated ~2 km below the seafloor off Japan as well as to detect and examine the signatures of the deepest microbial communities ever accessed by scientific drilling. We propose to investigate the diverse relationships between microorganisms and organic matter in the hydrocarbon system off the Shimokita peninsula. In particular, we intend to address the following questions: Does the coalbed act as geobiological reactor that sustains microbial life at great burial depth? Do the conversion and transport of coal-derived compounds influence carbon flow and biomass at depth and in the overlying shallower strata? How deep does the deep biosphere extend into the seafloor and what are the limiting factors for life? We intend to use organic geochemical approaches including qualitative, quantitative, and molecular-isotopic analyses of gases, dissolved organic matter, and polar membrane lipids representative of live microbial biomass. We will test our hypothesis on the role of coalbeds as energy and carbon sources for the deep biosphere in cultivation-based laboratory experiments. In order to elucidate metabolic pathways we will use stable isotopes of carbon and hydrogen and the radioisotope of carbon as tracers. These techniques will provide insights into biodegradation of organic matter, quantities of prokaryotic biomass, and carbon metabolism and activities of microbial communities in sedimentary environments.
DFG Programme
Infrastructure Priority Programmes
