Early views on the continental margin of the eastern United States were derived from studies of land geology, since there was little information available at sea. The parallelism of the Appa- lachian mountains and the continental margin led to speculations about the relationship between the two. In the middle of the 19th century, and indeed, well into the early part of the 20th, much of the crystalline part of the Appalachian system was regarded as pre-Paleozoic in age and discussion of mountain building concen- trated on the folding of the sedimentary rock sequences of the Valley and Ridge Province rather than upon the whole system.
In 1846, James Dana suggested that early in the history of the earth the continents cooled first and maintained their eleva- tions while the oceanic areas, of volcanic character, continued to cool and subside through time. As a consequence, “Ruptures, elevations, foldings and contortions of strata have been produced in the course of contraction. The greater subsidence of the oceanic parts would necessarily occasion that lateral pressure required for the rise and various foldings of the Appalachians and like regions.” Chamberlin and Salisbury (1907) held similar views about the antiquity of continents and oceans, but pictured the oceanic areas as sinking because of their greater specific gravity to cause shear forces at the continental margins.
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The Atlantic Continental Margin
This synthesis covers stratigraphy, depositional processes, and geophysical interpretation of the major onshore and offshore marginal basins from Maine to the Bahamas, and includes an up-to-date review of thinking on regional tectonic history. Additional chapters discuss the theoretical aspects of thermal evolution, subsidence, and seismic stratigraphy as applied to this region. Geological resources including petroleum, water, sand and gravel, hard minerals, and heat flow are reviewed, and environmental hazards such as seismicity, coastal erosion, waste disposal and submarine instability as it relates to site of drilling platforms and mining are evaluated. A summary chapter reviews areas of controversy and suggests key topics for research.