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Blanco Formation

Blanco Formation
State Texas
Name Blanco Formation
Geologic age Phanerozoic | Cenozoic | Tertiary | Pliocene
Comments Sand, clay, limestone, gravel. Coarser with more gravel toward margin of deposit; weathers glaring white. Sand, fine to med. grained quartz, bedded to massive, light greenish gray, white, gray. Clay, silty, sandy, bentonitc, calcareous in part. Limestone, white, flaggy, thinbedded. Molluscan and vertebrate fossils. Thickness 75 ft, pinches out laterally.
Primary rock type sand
Secondary rock type clay or mud
Other rock types limestone; gravel
Lithologic constituents
Major
Unconsolidated > Coarse-detrital > Sand (Bed)
Minor
Unconsolidated > Fine-detrital > Clay (Bed)
Sedimentary > Carbonate > Limestone (Bed)
Unconsolidated > Coarse-detrital > Gravel (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
Izett, G.A., Wilcox, R.E., and Borchardt, G.A., 1972, Air-fall volcanic ash bed in lower Pleistocene deposits near Mount Blanco, Texas [abs.]: in Rocky Mountain Section, 25th Annual Meeting, Geological Society of America, v. 4, no. 6, p. 384.
Bureau of Economic Geology, 1983, Lubbock Sheet, Geologic Atlas of Texas: University of Texas at Austin, Bureau of Economic Geology, scale 1:250,000.
Counties Crosby - Lubbock