The geochemistry and mineralogy of samples collected along depth profiles from an As-rich tailing deposit with abundant calcite was studied to determine the processes that influence the mobility of Fe, Zn, Cu, Ni, Cd, As, Sb, Cr and Tl. In spite of their near neutral pH, almost all of them are acid potential generators. Total concentrations decreased as: Fe > As > Zn > Pb > Cu > Sb > Cd > Cr > ...

The southern part of Skull Valley has potential for shallowly buried mineral deposits. The most likely deposit type is either skarn/porphyry copper deposits, perhaps with surrounding polymetallic lead-zinc-silver replacement deposits or "distal disseminated" gold-silver deposits. The area (1) is structurally complex with both thrust and high-angle faults, (2) contains lithologic units favorable...

The carbonatite problem can be stated as follows: Are carbonatites genetically related to sedimentary carbonate rocks, or are they derived from a silicate parent material? The isotopic composition of strontium in 21 carbonatites and in several related alkaline rocks has been determined. The mean Sr87/$r86 ratio for the 21 carbonatites is 0.7065 + 0.0003. The Sr87/sr86 ratios of sedimentary carb...