Pleistocene marine shorelines offer a means of testing the balance model 

 of isostasy. If the ocean floor deforms under water loads , the amount of post- 

 glacial submergence of a coast should be in part a function of the regional 

 proximity of deep ocean water. Coasts with nearby ocean water more than 100 m 

 deep had the load of water from the postglacial rise of sea- level added early 

 and close; coasts bordering shallow seas had the load added late and generally 

 far offshore. An averaging technique to show the regional water load on the 

 Atlantic coast of the northeastern United States provides a basis for compar- 

 ing the submergence histories of several localities with the average water 

 depth offshore. In general, the amount of submergence is proportional to the 

 proximity of deep water. 



Oceanic islands should record different Pleistocene shoreline levels 

 than continental coasts. Local, detailed, late Pleistocene histories of a 

 variety of coasts will provide a test of isotasy better than the familiar test 

 of postglacial uplift. (Author). 



025 BLOOM, A. L. 1970. "Holocene Submergence in Micronesia as the Standard 

 for Eustatic Sea-Level Changes," Quaternaria . Vol XII, pp 145-154. 



The author discusses the effects of Holocene sea- level movements on a 

 "stable coast." Bloom used the small island of Micronesia as case studies and 

 found that slow subsidence averaged close to 3 cm per 1,000 years. (Gorman). 



026 BORN, G. H., TAPLEY, B. D., and RIES, J. C. 1986. "Accurate Measure- 

 ment of Mean Sea-Level Changes," Journal of Geophysical Research . Vol 91, 

 No. CIO, Vol 11, pp 775-11, pp 782. 



This paper examines a novel yet simple technique for monitoring changes 

 in global mean sea- level over periods of weeks to years with an accuracy of a 

 few centimeters using altimeter data from a well-tracked satellite. The tech- 

 nique is based on the following argument. A satellite's orbit period and, 

 hence, the mean semimajor axis of the orbit, are accurately determined by 

 tracking systems located on the earth's surface. With laser or radiometric 

 tracking systems, the mean semimajor axis can be determined with an accuracy 

 of better than a centimeter. If the satellite carries an accurate altimeter, 

 the difference between the mean semimajor axis and the global mean height 

 measured by the altimeter is mean sea- level. Any temporal change in the mea- 

 surement of sea- level must be due to drift in the altimeter or to change in 

 the volume of the sea. To demonstrate the application of this technique, the 

 fully corrected altimeter measurements of sea-level obtained by Seasat during 

 a 24-day period when the satellite was in an exactly repeating orbit were sep- 

 arated into eight 3-day segments and averaged over each of these periods. The 

 calculated mean sea-level relative to the Goddard Earth Model-lOB geoid varied 

 over a range of +7 cm during these eight periods. The variation is due pri- 

 marily to errors in the vertical component of the satellite's ephemeris, which 

 had a standard deviation of approximately 1.3 m. The results have important 

 consequences. The proposed Topex/Poseidon altim6tric satellite mission should 

 have an ephemeris error of around 10 cm, and the satellite's ground track will 

 repeat every 10 days. Thus, we expect that data from this satellite could be 



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