Text Appearing Before Image: said to constitute a mappableunit in the counties of Grayson, Cooke, Denton, Tarrant, and Johnsononly, and is therefore of less areal importance than other subdivi-sions of the Washita division. Its lithologic identity fades out to thenortheast in Indian Territory, but is distinctly recognizable in theChickasaw Nation northwest of Marietta. It continues as a recog-nizable formation as far south as the Brazos, being exposed 4 milesnorth of Blum and south of Rio Vista. South of the Brazos thisformation loses its lithologic and paleontologic identity, its positionbeing occupied on the Colorado by the lithologic phase of the George-town limestone in that direction. These beds have a total estimatedthickness of about 194 feet at Denison and about 40 feet at FortWorth.1 1 The Duck Creek fossils occur in the base of a bluff north of the public square. This containsGvyphxanavia, Hamites fremonti, and Iaehydiscu* brazoensis. U. S. GEOLOGICAL SURVEY TWENTY-FIRST ANNUAL REPORT PART III PL. XXXV Text Appearing After Image: UfflVffWTY of ILLINOIS HILL.) LOWER CRETACEOUS BEDS AT FORT WORTH. 259 FOKT WORTH FOUMATIOX. DEFINITION AND GENERAL CHARACTER. The term Fort Worth formation as originally applied by the writerwas used for a conspicuous white limestone and marl formation whichmay be traced almost entirely across Texas. For reasons which willbe apparent in the following pages, this name will hereafter be usedin a more restricted sense for that portion of the formation lyingnorth of the Brazos, and the term Georgetown formation will be usedfor its modified continuation south of that stream. The Fort Worth formation, as exposed in the railway cuts north ofthe Union Station at Fort Worth (see fig. 31), and underlying all the
Note About Images
Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.
The categories of this image need checking. You can do sohere.
Please remove redundant categories and try to put this image in the most specific category/categories.
You can remove this template by clicking here (or on the first line).
Licensing
This image was taken from Flickr's The Commons. The uploading organization may have various reasons for determining that no known copyright restrictions exist, such as:
The copyright is in the public domain because it has expired;
The copyright was injected into the public domain for other reasons, such as failure to adhere to required formalities or conditions;
The institution owns the copyright but is not interested in exercising control; or
The institution has legal rights sufficient to authorize others to use the work without restrictions.
Please add additional copyright tags to this image if more specific information about copyright status can be determined. See Commons:Licensing for more information.
No known copyright restrictionsNo restrictionshttps://www.flickr.com/commons/usage/false