An official website of the United States government. Here's how you knowHere's how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Latest Earthquake | Chat Share
The High Point paleosol is 2.28-meters-thick aggradational soil developed in fining upward estuarine-alluvial sand and loess. The paleosol is exposed in a few shoreline cliff faces of Mason Neck, Virginia. Although a former A horizon is missing, the E, Bw, Bt, and C horizon sequence seen in the sediments indicates subaerial pedogenesis. Pedogenesis began with initial estuarine-alluvial floodplain emergence as sea level was lowering in late marine isotope stage 5 (MIS5) and MIS4, continued during eolian silt deposition accompanied by incorporation of the silt into the estuarine-alluvial sand, and ended with a period of loess and eolian sand deposition, erosion, and development of periglacial(?) features. Six optically stimulated luminescence ages provide an age range from 86 to 56 ka (thousand years ago) for sedimentary units below and above the paleosol. These ages indicate a 10,000- to 30,000-year interval in late MIS5 and MIS4 for these events to have occurred.