Geology topics

D. Dale Condit

Publications and source records attributed to D. Dale Condit.

3 recordsLinked to original sources

USGS1927

Phosphate rock in the Three Forks-Yellowstone Park region, Montana

The region described is about 7,000 square miles in area. It includes most of Gallatin and Madison Counties, in Montana, and some contiguous parts of Idaho and Wyoming. Within it are several broad fertile valleys and a number of prominent mountain ranges. A considerable part is underlain by a bed of phosphate rock which occurs in the Phosphoria formation, of Permian age, and is elevated to the surface of the mountainous area. In most of the middle and southwestern parts of the region this deposit is about 2 feet thick; locally it is 3 feet or more. Outcrops of beds in which the deposit is more than 6 inches thick aggregate more than 200 miles in length. Toward the northeast the deposit thins out, and its limit in that direction is represented fairly accurately by a line drawn from Yellowstone Park northwestward through Salesville to Willow Creek, on Jefferson Kiver. Its thicker parts contain 45 to 65 per cent of tricalcium phosphate. In this region the phosphate deposit is thinner and of poorer quality than in the adjoining parts of Montana on the west and northwest, where it is commonly 4 feet thick and contains 65 to 70 per cent of tricalcium phosphate. In southeastern Idaho the deposit is still thicker and richer.

Montana↗

USGS1919

Relations of late Paleozoic and early Mesozoic formations of southwestern Montana and adjacent parts of Wyoming

The object of this paper is twofold - to present evidence found in southwestern Montana concerning the great Jurassic base-leveling and its bearing on the solution of certain stratigraphic problems involving late Paleozoic, Triassic, and Jurassic formations, and to set forth the relations of those formations to beds in western Wyoming.

Montana, Wyoming↗

USGS1917

Relations of the Embar and Chugwater formations in central Wyoming

The information set forth in this chapter was obtained in field work during the seasons of 1913 and 1915. During 1913 the writer was engaged in the detailed mapping of the phosphate beds of the Ember formation on the northeast slope of the Wind River Mountains and in the Owl Creek Mountains as far east as Bighorn River canyon. In 1915 the mapping was continued eastward as far as Holt, from which a reconnaissance examination was made east and north along both flanks of the Bighorn Range as far as the latitude of Tensleep. A visit was also made to the west end of the Rattlesnake Mountains and neighboring points in Natrona County, to the Conant Creek anticline, in the eastern part of Fremont County, and to the Sheep Mountain anticline, in the Bighorn Basin.

Wyoming↗