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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↗
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↗
USGS1953

Geologic map of Lake Valley manganese district, Sierra County, New Mexico

The Lake Valley district was originally developed as a manganese-silver district, but the known silver-bearing ore bodies have long since been worked out. The critical shortage of manganese during World War II renewed interest in the manganese deposits; from October 1941 through June 1942 the U. S. Geological Survey and the U.S. Bureau of Mines conducted a cooperative exploration program in the district. This exploration demonstrated that the Lake Valley district contained about 175,000 tons of ore; approximately 37,000 tons has subsequently been mined. The present reserves are estimated to be approximately 140,000 tones of ore with a manganese content of more than 10 percent and an average content of 16.4 percent; about 75,000 tons of the ore has manganese content of more than 15 percent and an average content of 20.7 percent.

New Mexico↗
USGS1952

Geology of the Iron King Mine, Yavapai county, Arizona

The Iron King mine is about 2,000 feet west-northwest of the intersection of the 112 15 west meridian and the 34 30 north parallel in the Humboldt region in central Yavapai County , Arizona . The mine is approximately in the geographical center of the Humboldt region. Precambrian rocks form the bedrock. Late Cenozoic unconsolidated river wash and valley fill with some interbedded basalt locally mantle the Precambrian rocks, especially in the north-central part of the region. The Precambrian rocks consist of two metamorphosed volcanic formations and intrusive rocks that range in composition from quartz porphyry to gabbro. The volcanic formations originally were flows, volcanic breccias, and tuffaceous sedimentary rocks. Dynamothermal metamorphism of these rocks formed textures, structures, and mineral assemblages characteristic of low-grade ;riietamorphic rocks, but sufficient relict textures and structures remain to permit delineation of formations on the bases of their original nature. All the Precambrian rocks are foliated, except those in the interior parts of the larger intrusive masses. This foliation has two major trends, (1) north to N 20° W, and (2) N 20° E. The northeast-trending foliation is younger and locally is superimposed on the north- to northwest-trending foliation. The Precambrian rocks strike north to northwest and dip steeply, chiefly westward. Duplication of stratigraphic units and determination of tops suggest two major northeast-trending folds, which probably plunge southward. The northeast-trending foliation appears to bear an axial-plane relationship to these folds. Some masses of igneous rock probably were intruded during development of foliation. The Iron King deposit supports the only active mine in the Humboldt region. It consists of 12 steeply plunging echelon veins arranged along the footwall of a sheared and altered zone in the metamorphosed andesitic tuffaceous sedimentary rocks. Narrow zones of more intense shear probably localized the veins. Solutions first introduced quartz, pyrite, ankerite, and sericite, forming a sporadically mineralized zone (in the hanging wall of the deposit) and probably veins in the Iron King fracture system. Intra-mineralization shear strongly brecciated these early minerals and formed the structures that localized and distributed the ore minerals in the veins. After this deformation, sphalerite, galena, chalcopyrite, tennantite, arsenopyrite, pyrite, quartz, and ankerite were deposited; the last three minerals may have formed through solution and the redeposition of earlier minerals. Formation of sericite either accompanied or followed the deposition of ore-forming minerals. Silver is related closely in distribution to copper and probably is in the tennantite. Gold occurs chiefly in the pyrite. Banding, mimetic after foliation and planes developed by shearing, is pronounced in much of the vein material. Mineral zoning, generally similar in each vein, is a characteristic of the deposit. High-angle reverse faults of about 100 feet in maximum vertical separation offset the veins. These faults are nearly parallel to the veins in strike and dip.

Arizona↗