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S. C. Creasey

Publications and source records attributed to S. C. Creasey.

At least 19 recordsLinked to original sources
USGS1978

Galiuro Volcanics, Pinal, Graham, and Cochise counties, Arizona

The Galiuro Volcanics occurs in the Galiuro, Winchester, and Little Dragoon Mountains, east and northeast of Tucson, Ariz. The sequence comprises lava flows and ash-flow tuffs ranging in composition from andesite to rhyolite. In general they can be subdivided into two parts separated by a major erosional unconformity. The lower part is predominantly lava flows ranging from andesite to rhyodacite but contains three ash-flow tuffs. The upper part is chiefly ash-flow tuff but also includes two areas of rhyolite-obsidian flows and domes and rhyolitic to andesitic flows. Conglomerate separates many if not all of the rock units in the upper part. The individual flows and tuffs are lenticular, and the stratigraphic relations are complex. Chemical variation diagrams suggest consanguinity among all the volcanic rocks, but the complex intercalation of rhyolite and andesite and of lava flows and ash-flow tuff indicates more than one magma chamber, different stages of differentiation in separate magma chambers, and several eruption centers. Chemical analyses indicate that the magmas were normal calc-alkaline. Eleven potassium-argon age determinations indicate that the Galiuro Volcanics accumulated from about 29 to 23 million years ago, which is in the middle of the mid-Tertiary volcanic and plutonic event in Arizona.

Arizona↗
USGS1977

Middle Tertiary plutonism in the Santa Catalina and Tortolita mountains, Arizona

Recent reconnaissance geologic mapping in the Santa Catalina and Tortolita Mountains of southeastern Arizona, supplemented by new and published potassium-argon and fission-track ages, suggests that a large composite batholith of middle Tertiary (about 25 million years) age crops out extensively in both mountains. More than two-thirds of the batholith and contiguous wallrocks is gneissic, the gneissosity comprising strong cataclasis and mylonitization, penetrative planar and linear structures, and crystallization of muscovite and biotite in the foliation planes. New radiometric ages indicate that the deformation followed the crystallization of the batholith so closely that the K-Ar dating method cannot distinguish a difference, whereas previously published ages from the gneisses indicate a short time between the two events.

Arizona↗
USGS1976

Middle Tertiary plutonism in the Santa Catalina and Tortolita Mountains, Arizona

Recent reconnaissance geologic mapping in the Santa Catalina and Tortolita Mountains of southeastern Arizona, supplemented by new and published potassium-argon and fission-track ages, suggests that a large middle Tertiary (about 25 m.y.) composite batholith crops out extensively in both mountains. More than two-thirds of the batholith and the contiguous wallrocks are gneissic, the gneissosity comprising strong cataclasis and mylonitization, penetrative planar and linear structures, and crystallization of muscovite and biotite in the foliation planes. New radiometric ages indicate the deformation followed the crystallization of the batholith so closely that the K-Ar dating method cannot distinguish a difference, whereas previously published ages from the gneisses indicate a short time interval between the two events.

Arizona↗
USGS1958

Geology and ore deposits of the Jerome area, Yavapai County, Arizona

The Jerome area, in central Arizona, includes the Mingus Mountain quadrangle and parts of the adjacent Clarkdale, Mayer, and Mount Union quadrangles. The largest copper mines in the area at Jerome are the United Verde Extension and the United Verde. The United Verde Extension, closed in 1938 and the United Verde closed in 1953. The Iron King mine at Humboldt, the most active mine in the area after 1953, produces lead and zinc.

Arizona↗
USGS1954

Geology of the Starr molybdenum mine, Okanogan County, Washington

The Starr molybdenum mine, Okanogan County, Wash., is about 5 airline miles west of Tonasket in the north-central part of the State. The mineralized zone has been explored to a depth of 250 feet by means of three adit levels, one sublevel, and a raise which connects two of the adits and the sublevel. In all, there are about 2,700 feet of underground workings. The mine has neither machinery nor a developed water supply adequate for any work other than a small exploratory program.

Washington↗