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Henry Rowland Cornwall

Publications and source records attributed to Henry Rowland Cornwall.

At least 19 recordsLinked to original sources
USGS1977

Igneous rocks and copper mineralization in the Ray porphyry copper district, Arizona

The Ray porphyry copper district is approximately 110 km north of Tucson and 120 km east-southeast of Phoenix in southeastern Arizona. The major disseminated copper deposit at Ray has reserves estimated at 650 million tonsl of both primary and secondary ore, and occurs mostly in Precambrian Pinal Schist and diabase, but partly in the Granite Mountain Porphyry of Laramide age. The Granite Mountain Porphyry is part of a suite of Laramide igneous plutons and dikes in the Ray area that range in age from 70 to 60 m.y. and in composition from diorite to quartz monzonite. Hydrothermal biotite from the copper deposit at Ray has been dated at 65 m.y. (K-Ar age), and apatite in mineralized diabase has been reset at 60 m.y. (fission-track age). These ages indicate a close temporal and possibly genetic relationship with these Laramide igneous rocks.

Arizona↗
USGS1968

Hypogene veins of gibbsite, pyrolusite, and lithiophorite in Nye County, Nevada

Gibbsite, lithiophorite, pyrolusite, and goethite, plus discrete mixtures of gibbsite and lithiophorite and of gibbsite and iron oxide, occur as replacement veins in limestone. Minor accessories are barite, alunite, opal. Minerals of wall-rock alteration are garnet, idocrase, K-feldspar, prehnite, sericite, and quartz. These silicates formed at higher temperature than the vein minerals, but the whole sequence is considered to be a product of the same solutions, of deep-seated origin, deposited over a long period of time.

Nevada↗