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Disposal of Spent Fuel and High-Level Waste
Published in James H. Saling, Audeen W. Fentiman, Radioactive Waste Management, 2018
James H. Saling, Audeen W. Fentiman
Salt studies. National, regional, and area surveys resulted in activities in three identified areas, namely the Paradox basin, the Permian basin, and the Gulf Coast basin.31 The Paradox basin covers an area of about 28,500 km2 (11,000 square miles) including southeastern portions of Utah and southwestern portions of Colorado. It is composed of roughly 30 individual salt beds with depth varying from 122 m (400 ft) to 2720 m (8920 ft) and thickness from 46 m (150 ft) to 2900 m (9505 ft). The Permian basin covers an area of approximately 310,680 km2 (120,000 square miles) including portions of Kansas, Oklahoma, Colorado, Texas, and New Mexico. The depth of the basin varies from 137 to 1160 m (450–3810 ft), and thickness varies from 9 to 260 m (30–853 ft). The Gulf Coast basin contains both salt beds and salt domes, covering an area of about 298,000 km2 (115,000 square miles); it encompasses parts of Alabama, Louisiana, Mississippi, and Texas and extends southward beneath the Gulf of Mexico. Thickness of the salt beds is estimated to be 305–5334 m (1000–17,500 ft). The number of salt domes is estimated to be more than 300, with diameters varying from 1.6 to more than 6.4 km (1–4 miles) and depths ranging from 20 to 3050 m (65–10,000 ft).32 One site (Deaf Smith location) in the Permian basin was nominated for recommendation. Repository conceptual design and waste package design in salt have also been studied.6
Origin of the Neoproterozoic rim dolomite as lateral carbonate caprock, Patawarta salt sheet, Flinders Ranges, South Australia
Published in Australian Journal of Earth Sciences, 2020
R. A. Kernen, K. A. Giles, P. L. Poe, C. E. Gannaway Dalton, M. G. Rowan, J. C. Fiduk, T. E. Hearon
The rim dolomite includes a blue-grey to grey, yellow-tan, and pink micritic dolomite (Figure 9). The rim dolomite displays four distinct capstones types match descriptions by Poe et al. (2018) of caprocks found along the salt–sediment interface in the Paradox Basin (Utah) and the Gulf Coast (Texas). The four rim dolomite capstone types are: (1) massive—microcrystalline dolomite; (2) porphyritic—two distinct crystal sizes, one forming microcrystalline dolomite groundmass and the other forming rosettes of silica; (3) banded—microcrystalline dolomite forming pressure-dissolution layers of silica and authigenic hematite; and (4) brecciated—mosaic to disorganised subfabrics forming a microcrystalline dolomite groundmass. All capstones contain various amounts of anhydrite, quartz, feldspar and non-evaporite grains.
Vanadium as a critical material: economic geology with emphasis on market and the main deposit types
Published in Applied Earth Science, 2022
George J. Simandl, Suzanne Paradis
The Salt Wash category is named after the Salt Wash member of the Morrison Formation within the Paradox Basin, Colorado, U.S.A., which is hosted in selectively reduced (grey) continental fluvial sandstones within a sequence of continental red bed (oxidised) sediments. Distribution of vanadium-uranium mineralisation is mostly controlled by detrital carbonaceous (reducing) material and paleo-permeability and porosity within the sandstones. Individual, reduced, grey, organic material-rich zones enveloping vanadium-bearing zones are from 500 m to 4 km long, 50–300 m wide and up to 20 m thick. Vanadium-uranium deposits within these reduced zones are smaller and typically range from 100 to 500 m in length, 10–50 m in width, and 1–10 m in thickness (International Atomic Energy Agency 2009). Mineralisation commonly impregnates the sandstone matrix (Figure 3(a,b)) forming irregularly shaped lenticular masses oriented parallel to the bedding and following depositional trend within reduced (grey, lesivated) sediments. Consequently, the reserves of individual deposits rarely exceed 1 million tonnes of ore and are commonly much less (e.g. George R. Simpson and Gloria Emerson mines, Arizona; Chenoweth 2018). According to International Atomic Energy Agency (2018, 2020), individual deposits may contain from 1 to 2000 tonnes U grading 0.05–0.50% U, but the high vanadium content historically made these deposits attractive exploration and development targets. Vanadium-uranium weight ratios for the mineralisation of Salt Wash category range from 1:1 to 20:1 (Dahlkamp 2010) and deposits with the best potential for vanadium recovery generally exceed 1% V2O5 and some may have grades exceeding 2.5% V2O5 (Kelley et al. 2017). Because of large variations in grade and tonnage and in the vanadium-uranium ratio, and because several high-grade deposits of this type were artisanally-mined and records are not well preserved, Table 2 represents the most convenient way to show that under favourable conditions this deposit type may represent a viable exploration target. This table summarises the vanadium and uranium productions from Salt Wash member of the Morrison Formation within the Paradox Basin by district and indicates that uranium price may be a significant factor determining the desirability of this deposit type as a vanadium exploration/development target.