"whole-shelf" survey is also warranted in the light of the potentially small variations in bulk 

 geochemical properties, such as 8 13 C TOC (due to dilution of discrete signatures). We hope to 

 magnify these variations through molecular-level structural and isotopic measurements, however, 

 in order to "calibrate" the observed compositional variations we need to fully characterize the 

 magnitude and chemical signatures of the end-member source terms. For these purposes, 

 sampling end-member inputs is essential. 



STATUS OF RESEARCH 



We have made substantial progress since the project's inception. The samples we have 

 studied to date are derived from 2 successful field programs - a 5-day cruise to Georges Bank 

 (April, 1993), and a 14-day cruise from Georges Bank to Cape Hatteras (April, 1994). Principal 

 objectives of the first cruise were to test equipment, perform a methodology intercomparison for 

 DOC sampling and measurements, collect DOC samples during a period of high phytoplankton 

 productivity, and collect cores for macromolecular characterization and compound specific 

 (biomarker) carbon isotope analyses. 



Keywords: POC/DOC/COC, polymers, POM, DOM, mass spectrometer 



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