York River Geology

Abstract

Abstract The four separate sites of the Chesapeake Bay National Estuarine Research Reserve in Virginia are within the Coastal Plain province of the mid-Atlantic. The surficial geology at each site is of Quaternary age, primarily Holocene wetlands. The site at Taskinas Creek is set into Tertiary age strata. The underlying strata increase in age up-stream. Regionally, the Late Tertiary and Quaternary geology is a function of the series of major transgressions and regressions, during which the successively more recent high stands of sea level generally have not reached the level of the preceding high stand. As a consequence, stratigraphically higher, younger deposits occur topographically below exposures of the older strata. The two down-stream reserve sites are within the area of the Eocene age Chesapeake Bay Impact Crater. Also at these two sites, the tidal marshes are superimposed on a ridge and swale topography. The local rate of sea-level rise, approximately 4 mm/yr, is the underlying process driving ch...