southern half of the Chesapeake Bay (Fig. 1). Although fetch restrictions 

 result in a low to moderate energy wave climate (Rosen, 1976), there is an 

 extremely high and variable erosion rate (x = 0.94 m/year, Fig. 2). The Bruun 

 Rule was utilized to determine how much of this erosion can be accounted for 

 by the rise in sea-level. (Introduction). 



300 ROSS, C. A. and ROSS, J. R. P. 1988. "Late Paleozoic Transgressive- 

 Regressive Deposition," Wilgus, C. K. , Hastings, B. S., Kendall, C. G., 

 Posamentier, H. W. , Ross, C. A., and Van Wagoner, J. C, eds . , Sea-Level 

 Changes: An Integrated Approach . Special Publication No. 42, Society of 

 Economic Paleontologists and Mineralogists, Tulsa, OK, pp 227-248. 



Approximately sixty transgressive-regressive depositional sequences are 

 present in Carboniferous and Permian shallow-marine successions on the world's 

 stable cratonic shelves. These sequences were synchronous depositional events 

 that resulted from eustatic sea- level changes. Based on currently available 

 age correlations of rapidly evolved late Paleozoic tropical, subtropical, and 

 temperate shelf faunas, the sequences on different cratonic shelves were time 

 equivalent. These transgressive-regressive sequences averaged about 2 million 

 years and ranged from 1.2 to 4.0 million years in duration. 



Local depositional conditions are important in controlling sedimentary 

 patterns on different cratonic shelves. These conditions are affected by 

 changes in sea- level, strandline position, and drainage base level and are 

 reflected in the sedimentary record. Because midsize sea-level fluctuations 

 are usually widely identifiable in the stratigraphic record, they are useful 

 aids in correlation. They are particularly helpful between regions that have 

 contrasting depositional conditions, such as between a carbonate shelf starved 

 of clastic sediments and a clastic-dominated shelf on which carbonates are 

 rare. 



The appearance of new species and generally occurs above unconformities 

 that signal new marine transgressive events and new depositional sequences. 

 The durations of the hiatuses between these transgressive-regressive sequences 

 are difficult to estimate. The hiatuses may represent cumulatively as much 

 time, if not more, than the rock record. The numerous worldwide synchronous 

 unconformitites marking hiatuses of considerable duration within late 

 Paleozoic shelf strata suggest that the fossil record may be very incomplete 

 an preserves mostly biota that were extant during times of high sea- level. 

 Such an incomplete fossil record could easily be misinterpreted as a 

 punctuated evolution having a highly irregular mutation rate. (Authors). 



301 ROSSITER. J. R. 1960. "Report on the Reduction of Sea-Level 

 Observations (1940-1958) for R.E.U.N.: Permanent Service for Sea-Level," 

 Liverpool, England, pp 24. 



On the occasion of the R. E.U.N. Meeting at Liverpool in October, 1959, 

 the Permanent Service for Mean Sea-level (MSL) was requested by the R. E.U.N. 

 Commission to investigate further the possibilities of oceanographic levelling 

 around the European coastline. 



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