070 DEMAREST, J. M. , II, and KRAFT, J. C. 1987. "Stratigraphic Record of 

 Quaternary Sea-Levels: Implications for More Ancient Strata," Nummedal, 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 223-240. 



The stratigraphic record of Quaternary transgressions due to glacio- 

 eustatic rise varies as a function of sediment supply from rivers to the 

 paralic realm. Extremes from low to high sediment supply are represented by 

 the Atlantic and Gulf coasts of the United States, respectively. 



The vertical sequence produced by these transgressions at the low 

 sediment supply end of the spectrum consists of paralic and fluvial lithosomes 

 erosionally truncated by shoreface retreat and overlain by shelf marine 

 lithosomes. The lithosomes produced in the landward portion of the paralic 

 realm are commonly preserved, whereas the lithosomes from the foreshoreward 

 part are less likely to be preserved. Thus, beach facies are rarely 

 incorporated into the transgressive stratigraphic record, except as a peak 

 sea- level deposit preserved by abandonment. Erosional truncation of the 

 paralic section produces a unique stratigraphic surface, three ravinement 

 surface, which exhibits many of the physical characteristics of a major break 

 in deposition. The surface is then overlain by nearshore to offshore shelf 

 facies in a deepening-upward succession. 



When encountered in the stratigraphic record, the ravinement surface is 

 likely not to be interpreted as a depositional sequence boundary. When this 

 occurs, a continuous cycle of deposition during transgression is not 

 recognized. When a ravinement and its associated facies are properly 

 interpreted, a complete cycle of transgression and regression in response to 

 changing sea-level can be recognized. (Authors) . 



071 DEMIRPOLAT, S., and TANNER, W. F. 1987. "Advanced Grain Size Analysis 

 and Late Holocene Sea-Level History," Proceedings of Coastal Sediments '87 . 

 Vol 2, pp 1718. 



Details of the history of changes in mean sea- level, average wave 

 conditions and storminess, for the most recent 3,000-5,000 years, can be 

 deciphered in many areas where (a) the coastal strip was stable over this time 

 interval, (b) a detailed record is available in short time increments (a few 

 decades: e.g. beach ridges), (c) the sediments are suitable for analysis. 

 One such area is described here. 



St. Vincent Island is located near the mouth of the Apalachicola River, 

 Fla., on the coast southwest of Tallahassee. It is a complex beach ridge 

 plain, having some 200 beach ridges. Deposition was spread over roughly 4,000 

 years, giving (average sense) one ridge per 20 years, with perhaps 400,000 or 

 more laminae (roughly one per week) . The materials are clean quartz sand. 



There are a dozen or more ridge sets; some stand high, some low. The 

 topographic differences reflect an up-and-down history of sea-level, over the 

 most recent 4,000 years, because they show distinct stable episodes spanning 

 100 or more years each. This cannot be due to storms. 



The variability diagram (Tanner, 1985) permits either a swash zone, or a 

 dune, interpretation. The external geometry and internal details require a 

 swash origin. The tail-of -fines diagram (Tanner, 1986) shows that the oldest 



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