Comparative analysis of multiple paleocontinental flooding records permits partial reconstruction of continental and global hypsometries, calculation of continental and global sealevel elevation trends, and isolation of elevation residuals that may record secular changes in hypsometry, for example, as a result of continental epeirog eny. Analysts of the flooding records of 13 Paleozoic landmasses suggests that the mid-Ordovician eustatic maximum was about 100 to 225 m above present sealevel, substantially lower than previous estimates of +300 m (Vail, Mitchum, and Thompson, 1977) to +600 m (Hallam, 1984) and closer to estimates of 175 to 250 m above present sealevel for the mid-Cretaceous eustatic maximum. The most important control on Paleozoic elevation estimates is choice of a modern hypsometric analog for scaling of paleo-hypsometries: an American analog yields elevations that are about 100 m higher than a Eurasian analog. Differences in the elevation scales between analogs result in dissimilar global hypsometries: relative to the modern world, a Eurasian analog yields gentle Cambro-Carboniferous and intermediate Permian hypsometries, whereas an American analog yields intermediate Cambro-Carboniferous and steep Permian hypsometries. These observations have important but unexplored implications for relationships between global tectonics, continental geomorphology, and eustasy. Variance in paleocontinental flooding records includes contributions from hypsometric, eustatic, and residual sources. Differences in the time-averaged mean hypsometry of paleocontinents account for the largest proportion of flooding variance (95 percent). Because continental hypsometry is closely linked to landmass area, corrections for variable landmass area are necessary in all hypsometric analyses of flooding records. Of the 5 percent of variance of non-hypsometric origin, eustatic factors account for only one fifth overall but from one to two thirds for paleocontinents with high-quality flooding records. The Paleozoic continents yielding the best records of eustasy are Baltica, North China/United China, Kazakhstania, and Siberia; Laurentia/Laurussia, although having a high-quality flooding record, exhibits almost no eustatic component to variance, making Its use as a global standard questionable.
