Review of the Geology of Texas Volume 1644
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1919 edition. Excerpt: ...of 5 to 15 feet, and subordinate layers of shaly clay that contain concretions of iron carbonate in the upper 50 feet. The Midway lies unconformably on the upper Cretaceous and has a thickness of 200 to 400 feet, perhaps averaging 260 feet. It outcrops in a narrow belt in Hopkins, Hunt, Rains, Van Zandt, Kaufman, Henderson, Navarro, Freestone, Falls, Robertson, Bastrop, Caldwell, Guadalupe, Bexar, Medina, Uvalde, Zavalla, and Maverick counties. In the western area of its outcrop the Midway is included in the lower part of the Myrick formation. In Caldwell and Bastrop counties it has been called the Lytton formation. Wilcox (also known as the Lignitic, the Sabine, the Sabine River, and the Timber Belt Formation) The Wilcox is marine only in the region of the Sabine River between Pendleton and Sabinetown. At Pendleton the strata are of lower Wilcox age, belonging to the Nanafalia substage of Alabama. At Sabinetown the beds are of, upper Wilcox age, or the Woods Bluff substage of Alabama. The marine Wilcox is mainly dark-colored, sandy, laminated clays, with glauconite, large concretions of iron carbonate, and lime nodules. The non-marine Wilcox of east Texas is composed of sands, sandstones and clays, often laminated, and beds of lignite, the whole being from 800 to 1,200 feet in thickness. In the northeastern area and the vicinity of the Rio Grande, the Wilcox overlaps and conceals the Midway, and rests directly upon the Upper Cretaceous. In the western part of the Gulf Coastal Plain, the Wilcox is composed for the most part of siliceous sands, and also contains glauconitic sands, lime, clays of various colors, and beds of lignite. The Wilcox occurring in eastern Maverick county, eastern and northern Zavalla county, southeastern Uvalde...
- 189 x 246 x 3mm | 132g
- 13 Sep 2013
- United States
- black & white illustrations