PRINCIPAL 

 INVESTIGATOR(S) 



James Bauer 



Virginia Institute of Marine Science 



College of William and Mary 



P.O. Box 1346 



Gloucester Point, VA 23062 



Ellen R. M. Druffel 

 Department of Geosciences 

 University of California - Irvine 

 Irvine, CA 92717 



PROJECT TITLE 



TRANSFORMATION RATES AND FATE OF DISSOLVED, 

 COLLOIDAL, AND PARTICULATE FORMS OF ORGANIC 

 CARBON IN OCEAN MARGINS 



AMOUNT OF FUNDING FY 1994: $89 K 



SUMMARY OF GOALS 



The research that our group is conducting as part of the Ocean Margins Program is 

 intended to directly ascertain the flux of dissolved, colloidal and particulate organic carbon along 

 and across the Atlantic continental margin. Through the use of natural isotopic tracers, the extent 

 and rates of transformation between each of these pools will also lead to a better understanding 

 of the interactions of organic carbon in its different physical states. Our main goals are: 1) to 

 differentiate the apparent radiocarbon age(s) of dissolved, colloidal and particulate organic carbon 

 (DOC, COC and POC) on different regions of the continental shelf and compare these ages to 

 those for the open North Atlantic Ocean (Sargasso Sea); 2) to identify the sources of organic 

 carbon to continental shelf waters; 3) to estimate the fluxes of organic carbon along and across 

 the continental shelf to the open ocean; and 4) on the basis of simultaneous measurement of 

 carbon and thorium isotopes in several fractions of the DOC and POC, determine the residence 

 times and transformation rates of carbon between each of the pools. 



SPATIAL AND TEMPORAL SAMPLING SCALES 



The spatial sampling scale for our program is the entire western Atlantic continental shelf 

 between George's Bank and Cape Hatteras. To date, our coverage has consisted of three 

 transects across the shelf: one south of Long Island, one between Chesapeake and Delaware Bays 

 and one at Cape Hatteras. Depth profiles are conducted at three stations on each transect, the 



