The Mount Taylor uranium deposit is located at the extreme eastern end of the Ambrosia Lake district in the Grants mineral belt of New Mexico. Ores are confined to the Westwater Canyon Member of the Jurassic Morrison Formation and are spatially related to meanders in the paleochannels which deposited the arkosic sands of this member. The shape of the deposit roughly resembles the roll fronts of the Wyoming Tertiary basins.

This deposit resembles the deposits of the Wyoming basins chemically as well. Arsenic, selenium, molybdenum, and several other less commonly analyzed trace elements occur in zones across the orebody, parallel with the direction of dip and indicative of a redox cell.

Mineralogically, however, the Mount Taylor deposit differs significantly from those in the Wyoming basins and, surprisingly, from most of the other deposits in the Ambrosia Lake district. It does not reside at an iron redox interface nor is it very pyritiferous. It does have concentrations of calcite along its downdip and bottom edges. Montmorillonite, chlorite, and kaolinite show a regular zonation from the unaltered downdip sediments, through the ore zone, and into the updip altered sediments. No primary uranium-bearing minerals have been identified.

The deposit shows a complex relation to organic materials in the sediments, indicating two periods of organic enrichment of the sediments. The nature of this relation implies that organic transport mechanisms may have been as important in ore genesis as inorganic mechanisms.

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