Category: Articles

Environmental Geotechnics Chen, L. Merey, S., Pecher, I. Okajima, J. Komya, A., Diaz-Naveas, J., Li, S., Maruyama, S., Kalachand, S. Kvamme, B., Coffin, R. Methane hydrate has become one promising energy resource for humankind. In this study, recent worldwide onshore/offshore drilling and production activities are analyzed. The most recent reports from sites such as Japan (2013 and 2017) and China (2017) show that the road towards… Read more »

Frontiers in Marine Science. Akam, S.A., Coffin, R.B., Abdulla, H.A., Lyons, T.A. Our data synthesis and broad interpretation emphasizes the importance of SMTZ as not only a methane sink but also an important diagenetic front for global DIC cycling. We further underscore the need to incorporate a DIC pump in methane-charged shallow marine sediments to models for coastal and geologic carbon cycling. This new understanding will… Read more »

Remediation Coffin, R., Mueller, J. Methane (CH4) in ecosystems originates from ancient petroleum formed deep within the earth and/or via microbial fermentation of organic carbon and subsequent reduction of carbon dioxide (CO2). Given the complexity of different ecosystems, origins of CH4 present can be difficult to determine. This issue was realized in a situation where an antimethanogenic in situ chemical reduction (ISCR) remedial amendment containing organic… Read more »

Paleoceanography And Paleoclimatology Stott, L., Davy, B. Shao, J. Coffin, R., Pecher, I., Neil, H., Rose, P. Seafloor pockmarks of varying size occur over an area of 50,000 km2 on the Chatham Rise, Canterbury Shelf and Inner Bounty Trough, New Zealand. The pockmarks are concentrated above the flat‐subducted Hikurangi Plateau. Echosounder data identify recurrent episodes of pockmark formation at ~100,000‐year frequency coinciding with Pleistocene glacial terminations…. Read more »

Paleoceanography Shao, J., Stott, L., Gray, W.R., Rae, J.W.B., Greenop, R., Pecher, I., Coffin, R.B., Neil, H. Identifying processes within the Earth System that have modulated atmospheric pCO2 during each glacial cycle of the late Pleistocene stands as one of the grand challenges in climate science. The growing array of surface ocean pH estimates from the boron isotope proxy across the last glacial termination may reveal… Read more »

Methanogens/Archaea produce methane. They are often the dominant microbes in reduced environments. Methanogenesis is a requisite component of conventional anaerobic bioremediation. If Archaea are not controlled, then in situ remedial actions employing conventional (i.e., no active control of Archaea) ERD amendments such as oils/lecithins, lactates/sugars, simple hydrogen release compounds or conventional ISCR reagents can generate excessive amounts of methane. At several sites where these conventional ERD/ISCR… Read more »

Methanogens/Archaea may be dominant microbes in reduced environments, and methanogenesis can be a component of anaerobic bioremediation. If Archaea are not controlled, then in situ remedial actions employing conventional (i.e., no active control of Archaea) amendments such as oils/lecithins, lactates/sugars, simple hydrogen release compounds, conventional/original ISCR reagents, etc. can generate excessive amounts of methane (CH4) during the reduction of carbon dioxide (CO2). Methane can also be… Read more »