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A.R. Kinkel

Publications and source records attributed to A.R. Kinkel.

5 recordsLinked to original sources
USGS1965

Age and metamorphism of some massive sulfide deposits in Virginia, North Carolina and Tennessee

Isotopic ages of vein and wall-rock samples have been determined on five massive sulflde deposits of the southern Appalachians. Vein mineral ages of about 1100 m.y. indicate that some ore bodies formed at least as early as the Grenville metamorphism, and probably soon after the formation of the enclosing gneiss and schist. Present textures of the ore were formed during subsequent metamorphic periods at about 450 m.y. and 300 to 330 m.y. ago.

North Carolina, Tennessee, Virginia↗
USGS1962

Observations on the pyrite deposits of the huelva district, Spain, and their relation to volcanism

The felsitic porphyritic rocks that occur with Lower Carboniferous shale or slate in the Huelva district , Spain , were examined at the Rio Tinto, Tharsis, and La Zarza mines. Most of the bodies of porphyry are not intrusive into the shale, but instead consist of rhyolite flows overlain by variable thicknesses of coarse and fine pyroclastic rhyolite. These lie conformably beneath the shale. The pyroclastic beds are the ore horizon, and the ore bodies are confined to this stratigraphic zone. Various modes of formation have been postulated for the ore bodies of the Huelva district . The apparent limitation of ore to one strati-graphic horizon for more than 100 kilometers seems to favor a modified syngenetic origin with metallic elements derived from volcanic emanations.

Economic Geology↗
USGS1962

The ore knob massive sulfide copper deposit, North Carolina: An example of recrystallized ore

Massive and disseminated pyrrhotite-chalcopyrite-pyrite ore replaced a fault zone in Precambrian Carolina Gneiss of Keith (1). Closely following sulfide deposition, vein sulfides and silicates in the wall rock were recrystallized under a rising temperature gradient to coarse-grained unoriented aggregates that contain late pyrite porphyroblasts in pyrrhotite. Boudinage, dilation, and flow structures are common.

North Carolina↗