USGS - science for a changing world

Mineral Resources On-Line Spatial Data

Alluvium in Rio Grande, subdivided into areas predominantly of clay

Alluvium in Rio Grande, subdivided into areas predominantly of clay
StateTexas
NameAlluvium in Rio Grande, subdivided into areas predominantly of clay
Geologic agePhanerozoic | Cenozoic | Quaternary | Holocene
Original map labelQac
CommentsFlood-plain and backswamp silt and clay--dark-gray to dark-brown or brownish-gray silt, clay, and silty clay. Contains minor amounts of medium to fine quartz sand. Interdistributary fine sediment of the Rio Grande delta. Mostly inactive; deposition occurs during floods that accompany large, relatively infrequent tropical storms. Unit burrowed by animals; locally very organic with abundant plant fragments. Extensively cultivated. Overlies older distributary sand deposits (Moore and Wermund, 1993b).
Primary rock typesilt
Secondary rock typeclay or mud
Other rock types
Lithologic constituents
Major
Unconsolidated > Fine-detrital > Clay (Bed)
Unconsolidated > Fine-detrital > Silt (Bed)
Map references
Bureau of Economic Geology, 1992, Geologic Map of Texas: University of Texas at Austin, Virgil E. Barnes, project supervisor, Hartmann, B.M. and Scranton, D.F., cartography, scale 1:500,000
Unit references
Moore, D.W. and Wermund, E.G., Jr., 1993b, Quaternary geologic map of the Monterrey 4 x 6 degree quadrangle, United States: U.S. Geological Survey Miscellaneous Investigations Series Map I-1420 (NG-14), scale 1:1,000,000.
Geographic coverageCameron - Hidalgo

Show this information as [XML] - [JSON]

AccessibilityFOIAPrivacyPolicies and Notices

Take Pride in America logoUSA.gov logoU.S. Department of the Interior | U.S. Geological Survey
URL: http://mrdata.usgs.gov/geology/state/sgmc-unit.php?unit=TXQac;0
Page Contact Information: Peter Schweitzer