silt sheet (TXQsi;0)

State	Texas
Name	silt sheet
Geologic age	Phanerozoic \| Cenozoic \| Quaternary \| Holocene
Original map label	Qsi
Comments	silt and fine sand in thin, locally discontinuous sheet winnowed from other 'windblown deposits', brush and grass covered, rests on various Pleistocene deposits; pale brown, very pale orange, and west of about long 98 degree 15 min., moderate reddish-brown, moderate-brown, and light yellow-brown fine to very fine quartz sand and silt. Slightly clayey, loose, subangular to rounded; median grain diameter 0.14-0.17 mm (Russell, 1981). Grain size and thickness decrease westward; forms a thin discontinuous sheet of eolian silt (loess) downwind of Baffin Bay.
Primary rock type	silt
Secondary rock type	sand
Other rock types
Lithologic constituents	Major Unconsolidated > Fine-detrital > Silt (Bed) Unconsolidated > Coarse-detrital > Sand (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	Russell, J.L., 1981, The south Texas eolian sand sheet, in Stelting, C.E., and Russell, J. L., eds., Modern depositional environments of sands in south Texas: Gulf Coast Association of Geological Societies, Field Guidebook, p. 43-46. Bureau of Economic Geology, 1975, Corpus Christi Sheet, Geologic Atlas of Texas, Bureau of Economic Geology, University of Texas at Austin, scale 1:250,000. 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. [http://pubs.er.usgs.gov/publication/i1420(NG14)] Bureau of Economic Geology, 1976, Laredo Sheet, Geologic Atlas of Texas, Bureau of Economic Geology, University of Texas at Austin, scale 1:250,000.
Geographic coverage	Brooks - Jim Wells - Kenedy - Kleberg - Nueces