Near Marathon in Brewster County, Texas — The American South (West South Central)
Denuded Ouachita Rock Belt
In highway cuts toward the east are excellent exposures of almost vertical rock layers - part of the Ouachita Fold Belt, a northeasterly trending, folded and faulted mountainous range which was uplifted about 275 to 290 million years ago. The deformation is comparable in age to the uplift that formed the Appalachian Range of the eastern United States. The term "Ouachita" for this earth formation comes from the Ouachita Mountains of Arkansas and Oklahoma. (These were named by the Indians, whose words were rendered into written language by the 16th century French explorers.)
In the hillside toward the northeast, the highly deformed strata are overlaid by almost horizontal layers of "younger" rock - formed about 135 million years ago. Erosion wore down the old mountains; and when the area was covered by the sea, the horizontal layers were deposited on the sea floor.
Later uplifting earth movement comparable in age to the forming of the Rocky Mountain range gently elevated this area, exposing it to erosional forces which have shaped the topography seen today.
This region abounds in vivid lessons in geology, and is under constant study by scientists.
Erected 1970 by State Historical Survey Committee. (Marker Number 1209.)
Topics. This historical marker is listed in this topic list: Natural Features.
Location. 30° 12.777′ N, 102° 59.305′ W. Marker is near Marathon, Texas, in Brewster County. Marker is on U.S. 90, 14 miles east of U.S. 385, on the right when traveling east. Touch for map. Marker is in this post office area: Marathon TX 79842, United States of America. Touch for directions.
Credits. This page was last revised on September 15, 2020. It was originally submitted on January 13, 2010, by Richard Denney of Austin, Texas. This page has been viewed 1,687 times since then and 158 times this year. Photos: 1. submitted on September 14, 2020, by James Hulse of Medina, Texas. 2, 3, 4. submitted on January 13, 2010, by Richard Denney of Austin, Texas. • Bill Pfingsten was the editor who published this page.