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JAMES E. DEACON AND W. L MINCKLEY
Fig. le. Rio los Positos, Cuatro Ciénegas basin, Coahuila, Mexico. This stream,
fed by a number of small springs, is about 1.5 meters across in the immediate foreground. Deposition of travertine and other salts along its channel precludes development of woody, riparian vegetation. Photograph by Charles Stone, August 1960.
aquatic animals in places far downstream from upstream segments of perennial flow, but this occurs only when water percolating through coarsegrained sediments of the channel is forced to the surface by transverse
deposits of impervious stone. Reaches such as this persist year-round,
especially in canyons where shaded from direct, intense insolation, and they
have long been important to the desert traveler—be it man, beast, fish,
or fowl.
Desert watercourses are plagued by extremes, and one of the most spectacular is the flash flood produced when local runoff concentrates into a
relatively narrow channel. Conditions in a smaller creek, or even in a river,
JAMES E. DEACON AND W. L MINCKLEY
Fig. le. Rio los Positos, Cuatro Ciénegas basin, Coahuila, Mexico. This stream,
fed by a number of small springs, is about 1.5 meters across in the immediate foreground. Deposition of travertine and other salts along its channel precludes development of woody, riparian vegetation. Photograph by Charles Stone, August 1960.
aquatic animals in places far downstream from upstream segments of perennial flow, but this occurs only when water percolating through coarsegrained sediments of the channel is forced to the surface by transverse
deposits of impervious stone. Reaches such as this persist year-round,
especially in canyons where shaded from direct, intense insolation, and they
have long been important to the desert traveler—be it man, beast, fish,
or fowl.
Desert watercourses are plagued by extremes, and one of the most spectacular is the flash flood produced when local runoff concentrates into a
relatively narrow channel. Conditions in a smaller creek, or even in a river,