Surface and Subsurface Features of the Late Pleistocene Beaumont Formation as Studied in a Proposed Supercollider Site in Liberty and Hardin Counties, Southeastern Texas: ABSTRACT

Abstract

ABSTRACT In 1987 an area in Hardin and Liberty Counties in southeastern Texas was a much-studied candidate site for the ill-fated Superconducting Super Collider. The site is on the outcrop of the upper Pleistocene Beaumont Formation, which locally was deposited by a sequence of meandering, avulsing, suspended-load, paleo-Trinity River courses, now preserved as a well-defined to poorly defined depositional topography. Test holes in meanderbelt ridges showed that channel and point-bar silty fine to very fine sands are almost everywhere covered by approximately 10 to 40 ft (-3 to 12 m) of CH and CL overbank clays. Where completely penetrated, sand bodies are approximately 20 to 50 ft (-6 to 15 m) thick. Pedogenic calcareous deposits and slickensides at depths well below any influence from present-day surface processes are probably parts of lower horizons of truncated now-buried soils generated during the accumulation of the Beaumont, or on the surface of the underlying Lissie Formation. The relationship of one of the paleo-meanderbelts to the uplifted topographic surface of the Hull salt dome suggests that the rise of the surface postdated deposition of the Beaumont. End_of_Record - Last_Page 756-------