The discovery and character of Pleistocene calcrete uranium deposits in the Southern High Plains of west Texas, United States

Finchite, Sr(UO2)2(V2O8)·5H2O, a new uranyl sorovanadate with the francevillite anion topology

“…Mr. Finch published extensively, including the highly cited 1967 USGS professional paper "Geology of epigenetic uranium deposits in sandstone in the United States," which is still recognized as a definitive work on the subject (Finch 1967). This publication was the culmination of many years (1949)(1950)(1951)(1952)(1953)(1954)(1955)(1956)(1957)(1958)(1959)(1960)(1961) Hall 2017;Hall et al 2019). Uranium mineralization is concentrated just above the modern water table in a 30-meter-thick section of calcareous siltstones and fine-grained sandstones capped by pedogenic calcrete up to 6 meters thick.…”

“…USGS geologists located the exposed mineralization in 2015 and collected samples of yellow uranyl vanadates that coat grains, fill vugs, and line fractures in a calcareous, very fine-grained to fine-grained sandstone and massive carbonate (Figure 1). Finchite is found in the late Pleistocene Tahoka Formation (Hall et al 2019), which is thought to be lacustrine based on regional facies relationships and fossil evidence (Frye 1968;Van Gosen and Hall 2017). The Tahoka Formation is exposed rimming approximately 30 large McGee, the lacustrine strata that host the Sulphur Springs Draw and nearby Buzzard Draw deposits were genetically associated with a large Pleistocene lake located downstream.…”

“…The Tahoka Formation is exposed rimming approximately 30 large McGee, the lacustrine strata that host the Sulphur Springs Draw and nearby Buzzard Draw deposits were genetically associated with a large Pleistocene lake located downstream. This large prehistoric saline lake has been named Lake Lomax and is the largest Pleistocene-age lake identified in the Southern High Plains region (Frye 1968;Van Gosen and Hall 2017).…”