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W. P. Pratt

Publications and source records attributed to W. P. Pratt.

12 recordsLinked to original sources

The U.S. Midcontinent: a new frontier for mineral exploration.

The north-central US Midcontinent is underlain by a considerable thickness of sedimentary rocks, mostly Paleozoic, which lie upon a heterogeneous basement of Precambrian granitoid and metamorphic rocks. This article describes a representative sample of Midcontinent geology and explains why the authors believe this region is a 'new frontier' for mineral exploration and discovery. -Authors

Episodes

Slides showing quantitative models for mineral-resource assessment of the Rolla 1 degree x 2 degrees Quadrangle, Missouri

Th.is report consists of nineteen 35-mm color slides sh.owing digital synthesis and quantitative modeling of five geologic recognition criteria for assessment of Mississippi Valley-type resource potential in the Rolla 1° x 2° quadrangle, Missouri. The digital synthesis and quantitative modeling (Pratt and others, 1982) was done to supplement an earlier manual synthesis and evaluation (Pratt, 1981). The five criteria synthesized in this study, and the sources of data used, are that most known deposits are: In dolomite of the Bonneterre Formation, near the limestone-dolomite interface, which is defined as ls:dol = 1:16 (Thacker and Anderson, 1979; Kisvarsanyi, 1982); Near areas where insoluble residues of "barren" Bonneterre Formation contain anomalously high amounts of base metals (Erickson and others, 1978); Near areas of faults and fractures in the Bonneterre Formation or in underlying rocks (Pratt, 1982); In "brown rock" (finely crystalline brown dolomite) near the interface with "white rock" (coarsely recrystallized, white or very light gray, vuggy, illite-bearing dolomite) (Kisvarsanyi, 1982); Near or within favorably situated digitate reef-complex facies (Kisvarsanyi , 1982).

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