Asymmetrical continental margin orogenic belts have superimposed mineralization belts also zoned asymmetrically toward low temperature in the foreland, suggesting orogenic redistribution of crustal metals. The quantity of uranium concentrated into deposits is maximum in a final forelandward zone. High-temperature Th-U concentrations are less prominent in rearward tectonic zones.

Unfavorability of tectonic zones oceanward of the batholith zone, for low-temperature uranium, predicted in 1970, is reviewed as a test of the metallo-tectonic concept, after 12 years of intensive exploration during the price peak.

Of 19 Pacific-margin countries containing island-arc, back-arc-flysch-basin, pluton-in-flysch, or batholith tectonic zones, three aggregate six uranium deposits (four of low temperature), nine prospects, and perhaps ten occurrences. Two more countries have one prospect each. One vein is in island-arc andesite. Two disseminations in basin flysch may represent submarine exhalations. Several high temperature veins are associated with alkaline plutons in flysch, and several high temperature replacement disseminations with "porphyry" copper/molybdenum deposits are known. Many uneconomic high temperature replacement disseminations in alkaline granite are known in the batholith zone. One economic dissemination is in a granite pluton contact zone and two supergene impregnations are in regolit over granite batholith. Several impregnations occur in basin sandstones derived from and overlying granite.

Strongest uranium mineralization in oceanward tectonic zones was associated with cratonization of oceanic rocks.

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