Edwards Plateau is a region of west-central
Texas which is bounded by the Balcones Fault to the south and east, the
Llano Uplift and the Llano Estacado to the north, and the Pecos
River and Chihuahuan Desert to
the west. San Angelo, Austin, San Antonio and Del Rio roughly
outline the area.
Geology and natural history
The bedrock consists primarily of limestone
, with elevations ranging between 100 ft.
and 3000 ft. Caves and springs (in wet years) are numerous. The
Plateau mostly lacks deep soil suitable for farming, though some
cotton, grain sorghum and oats are grown. Thin soil and rough
terrain areas are primarily grazing
with cattle, sheep and Angora goats
predominant. Several rivers cross the region, which
generally flow to the south and east through the Texas Hill Country toward the Gulf of Mexico; however, permanent surface water supplies are
sparse throughout the area, except for man-made reservoirs.
The area is well drained; rainwater flows into the Edwards Aquifer
recharge zone at the south
of the plateau to feed rivers to the south. Rainfall varies from 15
to 33 in. per year, on average, from northwest to southeast.
The Balcones Fault
is associated with
the Edwards Plateau formation. This fault line is an ecological
demarcation for the range definition of a number of species. For
example, the California Fan
, is known to occur only west of the Edwards
Plateau or Balcones Fault.
Earliest human settlement of this are was by Native American
was used and wandered about by Jumano
groups, than after the
extends into the Southern Plains
by the forrunners of the Lipan
and Mescalero Apaches
. After the
expulsion of the Apachean groups from the Plains by the Comanche
, this area was dominated by the Penateka
band of the Southern Comanche.
- Maria de Fátima Wade. 2003. The Native Americans of the
Texas Edwards Plateau, 1582-1799, University of Texas Press,
293 pages ISBN 0292791569, 9780292791565