@article {2443,
	title = {Linking lithology and land use to sources of dissolved and particulate organic matter in headwaters of a temperate, passive-margin river system},
	journal = {Geochimica Et Cosmochimica Acta},
	volume = {71},
	year = {2007},
	note = {30},
	month = {Sep},
	pages = {4233-4250},
	abstract = {A number of rivers have been found to transport highly aged organic matter [OM]; however, the sources of this aged material remain a matter of debate. One potential source may be erosion and weathering of headwater lithologies rich in ancient sedimentary OM. In this study, waters, suspended particulates, streambed sediments, rocks and soils from fourteen small headwater watersheds of a mid-size, temperate, passive margin river were sampled and characterized by Delta C-14, delta C-13, and POC/TPN ratios to identify sources of particulate and dissolved OM delivered to the river mainstem. These headwater sites encompass a range in lithology (OM-rich shales, OM-lean carbonate/mudstone facies, and OM-free crystalline rocks) and land use types (forested and agricultural), and allow investigation of the influence of agriculture and bedrock types on stream OM characteristics. Streams draining large areas of both agricultural land use and OM-rich lithology contain particulate OM [POM] that is more C-14-depleted than streams draining forested, shale-free watersheds. However, this is not sufficient to account for the significantly lower Delta C-14-POC measured in the river mainstern. Dissolved OM [DOM] Delta C-14 are in all cases enriched compared to POM from the same stream, but are otherwise highly variable and unrelated to either land use or lithology. POC/TPN ratios were likewise highly variable. POC and DOC delta C-13 signatures were similar across all watersheds. Based on isotope mass balance, C-14-free fossil OM sources contribute 0-12\% of total stream POM. Although these results do not unequivocally separate the influences of land use and lithology, watershed coverage by shale and agriculture are both important controls on stream A Delta C-14-POC. Thus export of aged, particle-associated OM may be a feature of river systems along both passive and active continental margins. (C) 2007 Elsevier Ltd. All rights reserved.},
	keywords = {ATCHAFALAYA RIVER, ATMOSPHERIC O-2, BLACK SHALE, continental-shelf, GULF-OF-MEXICO, marine-sediments, MINERAL, SPACE-TIME CLIMATE, STABLE-ISOTOPES, surface sediments, SURFACES},
	isbn = {0016-7037},
	doi = {10.1016/j.gca.2007.06.056},
	author = {Longworth, B. E. and Petsch, S. T. and Raymond, P. A. and Bauer, J. E.}
}
@conference {1775,
	title = {Regional variability in the ages and reactivities of riverine dissolved and particulate organic matter exported to a temperate ocean margin},
	booktitle = {ASLO Aquatic Sciences Meeting},
	year = {2007},
	note = {id: 477},
	month = {2007},
	address = {Santa Fe, NM},
	author = {Bauer, J. E. and Raymond, P. A. and Cole, J. J. and Petsch, S. T. and Longworth, B. E. and Caraco, N. F. and Keesee, E. J.}
}
@conference {1638,
	title = {A geostatistical approach to watershed sources of aged riverine organic matter to the Hudson-Mohawk River system},
	booktitle = {American Geophysical Union Fall Meeting},
	year = {2006},
	note = {id: 483},
	month = {2006},
	address = {San Francisco, CA},
	author = {Longworth, B. E. and Petsch, S. T. and Raymond, P. A. and Bauer, J. E.}
}
@conference {1790,
	title = {Sources age and composition of dissolved and particulate organic matter delivered to a passive margin river system},
	booktitle = {ASLO/AGU Ocean Science Meeting},
	year = {2006},
	note = {id: 485},
	month = {2006},
	address = {Honolulu, HI},
	author = {Petsch, S. T. and Gordon, E. S. and Longworth, B. E. and Schillawki, S. E. and Raymond, P. A.}
}
@inbook {1452,
	title = {Microbial transformations of organic matter in black shales and implications for global biogeochemical cycles},
	booktitle = {Geobiology: Objectives, Concepts, Perspectives},
	year = {2005},
	note = {id: 758},
	month = {2005},
	publisher = {Elsevier},
	organization = {Elsevier},
	author = {Petsch, S. T. and Edwards, K. J. and Eglinton, T. I.},
	editor = {Noffke, N.}
}
@article {2028,
	title = {Controls on the variability of organic matter and dissolved inorganic carbon ages in northeast U.S. rivers},
	journal = {Marine Chemistry},
	volume = {92},
	year = {2004},
	note = {id: 967},
	month = {2004},
	pages = {353-366},
	author = {Raymond, P. A. and Bauer, J. E. and Caraco, N. F. and Cole, J. J. and Longworth, B. E. and Petsch, S. T.}
}
@conference {1563,
	title = {Ancient organic matter sources to the Hudson-Mohawk River system: implications of riverine transport of ancient organic matter for the global biogeochemical},
	booktitle = {American Geophysical Union (AGU)},
	year = {2003},
	note = {id: 1027},
	month = {2003},
	address = {San Francisco, CA},
	author = {Longworth, B. E. and Raymond, P. A. and Petsch, S. T.}
}
@article {705,
	title = {14C-dead living biomass: evidence for microbial assimilation of ancient organic carbon during shale weathering},
	journal = {Science},
	volume = {292},
	year = {2001},
	note = {Petsch, S TEglington, T IEdwards, K JengHistorical ArticleResearch Support, Non-U.S. Gov{\textquoteright}tResearch Support, U.S. Gov{\textquoteright}t, Non-P.H.S.2001/04/03 10:00Science. 2001 May 11;292(5519):1127-31. Epub 2001 Mar 29.},
	month = {May 11},
	pages = {1127-31},
	abstract = {Prokaryotes have been cultured from a modern weathering profile developed on a approximately 365-million-year-old black shale that use macromolecular shale organic matter as their sole organic carbon source. Using natural-abundance carbon-14 analysis of membrane lipids, we show that 74 to 94\% of lipid carbon in these cultures derives from assimilation of carbon-14-free organic carbon from the shale. These results reveal that microorganisms enriched from shale weathering profiles are able to use a macromolecular and putatively refractory pool of ancient organic matter. This activity may facilitate the oxidation of sedimentary organic matter to inorganic carbon when sedimentary rocks are exposed by erosion. Thus, microorganisms may play a more active role in the geochemical carbon cycle than previously recognized, with profound implications for controls on the abundance of oxygen and carbon dioxide in Earth{\textquoteright}s atmosphere over geologic time.},
	issn = {0036-8075 (Linking)},
	doi = {10.1126/science.1058332},
	author = {Petsch, S. T. and Eglington, T. I. and Edwards, K. J.}
}
@article {2134,
	title = {A solid state 13C NMR study of kerogen degradation during black shale weathering},
	journal = {Geochim. Cosmochim. Acta},
	volume = {65},
	year = {2001},
	note = {id: 277},
	month = {2001},
	pages = {1867-1882},
	author = {Petsch, S. T. and Smernik, R. J. and Eglinton, T. I. and Oades, J. M.}
}
