of rise or in a fluctuating manner as suggested by the vertical spread of 

 radiocarbon dates from salt marsh sediments. Thus, a great detail of strati- 

 graphic control with precise timing was established. From this, the nature of 

 transgressive stratigraphic sequences was used to interpret paleogeographies 

 of this Holocene Epoch with potential projections of future coastal morpholog- 

 ies . (Author) . 



178 KRAFT, J. C, CHRZATOWSKI , M. J., BELKNAP D. F., TOSCANO. M. A., 

 FLETCHER, C. H. III. 1987. "The Transgressive Barrier-Lagoon Coast of 

 Delaware, Morphostratigraphy Sedimentary Sequences and Responses to Relative 

 Rise in Sea-Level," Numraedal, D., Pilkey, 0. H., and Howard, J. D., eds . , Sea- 

 Level Fluctuations and Coastal Evolution . Special Publication No. 41, Society 

 of Economic Paleontologists and Mineralogists, Tulsa, OK, pp 129-144. 



Transgressive barriers of the embayed Atlantic and Gulf coast are 

 generally similar in overall form, processes, and landward migration in 

 response to relative sea- level rise, but they vary greatly in potential 

 sources and volume of sand supply. Delaware's transgressive barriers vary in 

 thickness from 25 m to less than 5 m; dunes may rise to 20 m above sea- level, 

 whereas barrier-spit and inlet sand reach depths of 10-18 m below sea-level. 

 Widths vary between m at eroding headlands and 4-6 km near tidal delta and 

 spit complexes. 



A complete Holocene paralic sequence for Delaware includes a basal sand 

 and/or gravel overlain by marsh, lagoon, and barrier lithosomes. Shoreface 

 erosion, as the barrier lithesome moves landward, occurs to an average depth 

 of 10 m, with about 50% of eroded sediment derived from Holocene and 

 Pleistocene lagoonal mud outcrops. Since the suspended material is carried 

 out of the shoreface, its removal requires a re-evaluation of the volumetric 

 model commonly inferred from the Bruun mechanism. Also, the third dimension 

 of longshore transport of coarse material needs to be considered. 



As transgression continues, the ravinement surface exposes lagoonal 

 sediments, marsh mud, irregularly shaped basal remnants of the Holocene 

 barrier lithesome, or varied Pleistocene strata. These are then blanketed by 

 varying thicknesses of inner-shelf sand. Ultimately, the transgressive 

 barrier and associated paralic environments migrate landward to peak 

 interglacial positions where the entire transgressive record may be preserved. 

 A relatively complete vertical sequence of transgressive coastal lithosomes 

 might also be preserved at the outer edge of the continental shelf at glacial 

 sea- level minima. Thus, the optimal chance for total preservation of a 

 transgressive coastal lithesome sequence lies at the extremes, landward at the 

 peak interglacial when eustatic sea-level rise stops and the coastal lithesome 

 sequences become stranded, and possible on the outer edge of the shelf as 

 deglaciatien begins and there is rapid rate of sea-level rise. (Authors). 



179 KROOPNICK, P. M. 1985. "The Distribution of '^C of ECO, in the World 

 Oceans," Deep-Sea Research . Vol 32, No 1, pp 57-84. 



Measurements of the 6'^C ef total dissolved inorganic carbon (ECOj) in 

 the world oceans are presented. Most of the samples are from the GEOSECS 



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