bolson

From Spanish bolso (“a large pouch”).

bolson (plural bolsons)

1. (chiefly southwestern US) A relatively flat and arid valley that is surrounded by mountains and that drains into a central basin.
   • 1974, U.S. Department of the Interior, Geological Survey Research Professional Paper 900, p. 120 (Google preview):

     In three separate bolsons in West Texas, electrical-resistivity soundings and seismic-refraction profiles have been used . . . to estimate the alluvium thickness and ground-water quality.

   • 2011, Barry Lopez and ‎Debra Gwartney (eds.), Home Ground: Language for an American Landscape, →ISBN, p. 43 (Google preview):

     The image of a colossal purse is helpful in envisioning a bolson in the landscape: an extensive, saucer-shaped basin, closed at the bottom and surrounded on all sides by mountain slopes.

   • 2015 Nov. 2, David Crowder, "El Paso’s low water rates to rise," El Paso Inc. (retrieved 21 Nov 2015):

     The water in the Mesilla Bolson, which is recharged by the river above it, is part of a major lawsuit between Texas and New Mexico. . . . A settlement could impose new restrictions on wells tapping the bolson in both states.

• bolson at OneLook Dictionary Search

• SNOBOL, bolons