monolayer-equivalent levels, and if so, then is it replaced on mineral surfaces by marine organic 

 matter once entering the marine system? To address this question I would monitor riverborne 

 sediments entering the Chesapeake Bay, and examine cores in the transition region of the Bay. 

 I would hope to get some collaborative work done by the biomarker group. I would also like 

 to do some laboratory experiments that test for the mechanisms of this replacement (e.g., 

 metabolism of terrigenous organic matter vs. desorptive removal). 



SPATIAL AND TEMPORAL SAMPLING SCALES 



la. Small scale ridge and swale study. I envision seasonal cruises to sample sites in a restricted 

 set of shelf environments within close proximity (ca. 100 km), done during a year of intensive, 

 process-oriented water column and benthic work. Similar process-oriented studies might be done 

 in other areas in subsequent years (e.g., slope depocenter, canyons). 



lb. Map regional grain size relationships of OC burial. I envision collecting cores from 

 throughout the estuary-shelf-slope-rise region around the study area. Each site need be visited 

 only once, and timing is not tied to any process study. On the order of 10' - 10 2 cores will be 

 collected. 



2. Terrestrial vs. marine organic matter in estuaries. The riverine sampling of suspended 

 particulate matter would be done from shore over the course of a year, with emphasis on periods 

 of major sediment delivery (spring flood). Coring would be done on one estuarine cruise. 



METHODS AND PLATFORMS 



la. Small scale ridge and swale study. Coring to be done from shipboard, in conjunction with 

 other benthic group scientists in this process study. I would measure various parameters of 

 sedimentary organic matter, including measures of labile material (protein, perhaps plant pigments 

 if no one else is doing it) and total organic matter (C, N), and sediment specific surface area as 

 a textural indicator. 



lb. Map regional grain size relationships of OC burial. Box or Kasten cores to be collected 

 from shipboard (larger ships offshore, smaller vessels in coastal/estuarine regions). I will 

 measure total organic matter and sediment specific surface area, and would need radiometric 

 dating for sedimentation rates. 



2. Terrestrial vs. marine organic matter in estuaries. Riverine samples will be collected from 

 shore, so no platform is needed. Estuarine coring will be done from small vessel. I will measure 

 total organic matter and surface area, and will subcontract for stable isotope measurements. 



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