capturing sediments. Lagoonal salt marshes in southeastern North Carolina 

 accumulate 358 g m^ear'' of roots and rhizomes within their sediments. At an 

 average bulk density of 0.3 g cm"' the marsh can vertically accrete 1 . 2 mm 

 year"'. The average RSL rise for the past 40 years was 1 . 9 mm year"', thus 

 these salt marshes cannot maintain themselves through autochthonous production 

 alone. Large quantities of sand are available to these marshes through inlets 

 and historical data show that marshes disappeared when this sediment source 

 was eliminated. The predicted increase in the rate or RSL and the removal of 

 large quantities of sand for beach renourishment on developed barrier islands 

 may significantly hasten the drowning and disappearance of large areas of salt 

 marsh in the lagoons of southeastern North Carolina. (Authors). 



127 HAGGART, B. A. 1988. "A Review of Radiocarbon Dates on Peat and Wood 

 From Holocene Coastal Sedimentary Sequences in Scotland," Scottish Journal of 



Geology . Vol 24, No. 2, pp 125-144. 



One -hundred and fifty- eight radiocarbon dates from Holocene coastal 

 sedimentary sequences are assessed in terms of their tendency of relative sea- 

 level movement. Three subdivisions of greater, intermediate and lesser uplift 

 history are made in order to assess the degree of synchroneity or diachroneity 

 present in the data. The most successful demonstration of diachroneity is for 

 the initiation of the mid-Holocene fall in relative sea- level. This may 

 correspond approximately with the formation of the Main Postglacial Shoreline 

 throughout Scotland. (Author) . 



128 HALLAM, A. 1988. "A Reevaluation of Jurassic Eustasy in the Light of 

 New Data and the Revised Exxon Curve," 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 262-274. 



A comparison is made between the revised Exxon eustatic curve for the 

 Jurassic, based essentially on seismic stratigraphic analysis of North Sea 

 data, and a new curve derived from more conventional stratigraphic analysis. 

 The two curves are broadly similar in that a secular rise of sea- level through 

 most of the period is indicated on which about 17 shorter term cycles are 

 superimposed. Both record notable rises in the Sinemurian, Toarcian, 

 Bajocian, Callovian, Oxfordian, and Kimmeridgian. The Exxon curve, however, 

 misses the important event across the Triassic-Jurassic boundary and 

 underestimates the rate of rise in sea- level for a number of cycles. In 

 addition, some supposed eustatic events can be discounted as the consequence 

 of regional tectonics. Tectonic activity involving subsidence and uplift, 

 rather than geoid changes, is thought to be the principal cause of regional 

 distortions of the global picture. There is a need for better quantitative 

 data on the amplitude and rate of changes in sea-level. (Author). 



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