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S.P. Marsh

Publications and source records attributed to S.P. Marsh.

At least 19 recordsLinked to original sources
USGS1998

Major and trace element concentrations and correlations in mine dump samples from mining districts in Sierra, Socorro, and Otero counties, south-central New Mexico--Mockingbird Gap, Lava Gap, Salinas Peak, Goodfortune Creek, Bearden Canyon, and Sulfur Canyon mining districts of the northern San Andres Mountains, Sierra and Socorro County; Lake Valley mining district of Sierra County; and Tularosa and Orogrande mining districts of Otero County

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Open-File Report↗
USGS1991

Lower Paleozoic host rocks in the Getchell gold belt: Several distinct allochthons or a sequence of continuous sedimentation?

The lower Paleozoic rocks that host gold deposits along the Getchell gold belt in Humboldt County, Nevada, represent several allochthonous terranes rather than a sequence of continuous deposition. The term "terrane" is used only in a descriptive sense. Evidence for allochthonous terranes in this area includes fault boundaries and differences in age, lithology, and structural style among several rock sequences. The two most widespread and distinct terranes in the area are (1) the Osgood terrane, which consists of intensely deformed, regionally metamorphosed, marine rocks (Lower Cambrian Osgood Mountain Quartzite, Lower Cambrian to Lower Ordovician Preble Formation, and some rocks currently mapped as Comus Formation) and (2) the Getchell terrane, which consists of less deformed chert, clastic sedimentary rocks, and volcanic rocks (rocks mapped as Valmy and Vinini Formations, including Lower and Upper Ordovician and Lower Silurian strata in this region). Osgood-terrane bedding and foliation dip predominantly eastward, and folds verge westward. Getchell-terrane folds verge southeastward. The Comus Formation, which is Middle Ordovician at its type locality on Edna Mountain, represents a third terrane (Iron Point terrane) situated structurally between the Osgood and Getchell terranes. Use of the unit name Comus Formation outside the type locality has created confusion and needs reexamination. Some of the rocks currently mapped as Comus Formation might really be part of the other terranes.

Geology↗
USGS1984

Analytical results, geology, and sample locality map of mercury-sulfur-gypsum mineralization at Crater, Inyo County, California

The Crater mercury-su l fur-gypsum ~ineral ized area is located in east-central California along the crest of the Last Chance Range, west of the north end of Death Valley (fig. 1). The area is in the northwest quarter of the Last Chance Range 15-minute quadrangle and occupies the area between 117 39 and 117 45 longitude and 37 10 and 37 15 latitudP.. The area studied lies between 5000 ( 1525 m) and 6000 ( 1830 m) feet above sea level. Relief isgenerally moderate but can be extreme in some places, as at Hanging Rock Canyon (plate 1). The climate is arid, and there are no active streams in the area. The range fronts east and west of the area are precipitous and incised by many steep canyons, whereas the range crest has relatively low relief. The old abandoned town and mine site of Crater 1 ie in this area of low relief. Access to the Crater area is by paved and dirt roads from Big Pine to the west or from the north end of the Death Valley National Monument to the southeast.

California↗
USGS1981

Geochemical evidence for a Brooks Range mineral belt, Alaska

Geochemical studies in the central Brooks Range, Alaska, delineate a regional, structurally controlled mineral belt in east—west-trending metamorphic rocks and adjacent metasedimentary rocks. The mineral belt extends eastward from the Ambler River quadrangle to the Chandalar and Philip Smith quadrangles, Alaska, from 147° to 156°W. longitude, a distance of more than 375 km, and spans a width from 67° to 69°N. latitude, a distance of more than 222 km. Within this belt are several occurrences of copper and molybdenum mineralization associated with meta-igneous, metasedimentary, and metavolcanic rocks; the geochemical study delineates target areas for additional occurrences. A total of 4677 stream-sediment and 2286 panned-concentrate samples were collected in the central Brooks Range, Alaska, from 1975 to 1979. The −80 mesh (< 177 μm) stream sediment and the heavy (specific gravity > 2.86) nonmagnetic fraction of the panned concentrates from stream sediment were analyzed by semiquantitative spectrographic methods. Two geochemical suites were recognized in this investigation; a base-metal suite of copper-lead-zinc and a molybdenum suite of molybdenum-tin-tungsten. These suites suggest several types of mineralization within the metamorphic belt. Anomalies in molybdenum with associated Cu and W suggest a potential porphyry molybdenum system associated with meta-igneous rocks. This regional study indicates that areas of metaigneous rocks in the central metamorphic belt are target areas for potential mineralized porphyry systems and that areas of metavolcanic rocks are target areas for potential massive sulfide mineralization.

Alaska↗
USGS1979

Geochemical and generalized geologic map showing distribution and abundance of nickel, cobalt, lanthanum and yttrium in stream sediments, Chandalar 1° by 3° quadrangle, Alaska

This geochemical map shows the distribution and abundance of nickel (Ni), cobalt (Co), lanthanum (La), and yttrium (Y) in -80 mesh (177 micrometers) stream sediment samples in the Chandalar quadrangle, Alaska. The map is a part of a series of geochemical maps that together with the background information circular (Reiser and others, 1978) comprise the folio on the Chandalar quadrangle, Alaska. The data are plotted on a subdued base map showing the generalized geology, topography, and sample localities. Map symbols showing the ranges of metal values are indicated on the accompanying histograms and all values shown are considered anomalous. An explanation of sampling, preparation, and analytical procedures, and geochemical raw data for all samples are discussed by O'Leary and others (1976). The -80 mesh (177 micrometers) stream-sediment medium was used in this study because, given the rather restrictive time and manpower constraints, this medium combined with panned concentrates was determined to be the most economical and adequate medium in this area of the north-central Brooks Range where clastic sediments are derived from local bedrock. The study area is generally one of high relief with short fast moving streams and broad glacial valleys. All samples were taken from active streams, as close to the center channel as possible. All sediments were considered to be locally derived. Care was taken, when sampling an obviously glaciated terrane, to sample above or upstream from morainal material, wherever possible. Most samples were taken in areas where bedrock was within 30 m of the sample site.

Alaska↗
USGS1978

Geochemical and generalized geologic map showing distribution and abundance of molybdenum, copper, and lead in stream sediments in the Chandalar Quadrangle, Alaska

This geochemical map shows the distribution and abundance of molybdenum (Mo), copper (Cu), and lead (Pb) of -80 mesh (177 micrometers) stream sediment samples in the Chandalar quadrangle, Alaska. The map is a part of a series of geochemical maps that together with the background information circular (Reiser and others, 1978) comprise the folio on the Chandalar quadrangle, Alaska. The data are plotted on a subdued base map showing the generalized geology, topography, and sample localities. Map symbols showing the ranges of metal values are indicated on the accompanying histograms and all values shown are considered anomalous. An explanation of sampling, preparation, analytical procedures and geochemical raw data for all samples are discussed by O'Leary and others (1976). The -80 mesh (177 micrometers) stream sediment medium was used in this study because of the regional setting in the north-central Brooks Range. Given the rather restrictive time and manpower constraints the -80 mesh (177 micrometers) stream sediment combined with panned concentrates was determined to be the most economical and adequate medium in this case where clastic sediments are being derived from local bedrock. The study area is generally one of high relief with short fast-moving streams and broad glacial valleys. All samples were taken from active streams, as close to the center channel as possible. All sediments were considered to be locally derived. Care was taken, when sampling an obviously glaciated terrane, to sample above or upstream from morainal material, wherever possible. Most samples were taken in areas where bedrock was within 30 m of the sample site.

Alaska↗
USGS1978

Geochemical and generalized geologic map showing distribution and abundance of zinc in stream sediments in the Chandalar Quadrangle, Alaska

This geochemical map shows the distribution and abundance of zinc in -80 mesh (177 micrometers) stream sediment samples in the Chandalar quadrangle, Alaska. The map is a part of a series of geochemical maps that together with the background information circular (Reiser and others, 1978) comprise the folio on the Chandalar quadrangle, Alaska. The data are plotted on a subdued base map showing the generalized geology, topography, and sample localities. Map symbols show the metal values that are considered anomalous; these symbols are defined on the accompanying histograms. An explanation of sampling, preparation, analytical procedures and the geochemical raw data for all samples are presented by O'Leary and others (1976). The -80 mesh (177 micrometers) stream sediment medium was used in this study because of the regional setting in the north-central Brooks Range. Given the rather restrictive time and manpower constraints the -80 mesh (177 micrometers) stream sediment combined with panned concentrates was determined to be the most economical and adequate medium in this case where clastic sediments are being derived from local bedrock. The study area is generally one of high relief with short fast-moving streams and broad glacial valleys. All samples were taken from active streams, as close to the center channel as possible. All sediments were considered to be locally derived. Care was taken, when sampling an obviously glaciated terrane, to sample above or upstream from morainal material, wherever possible. Most samples were taken in areas where bedrock was within 30 m of the sample site. Due to poor sensitivity for zinc by spectrographic analysis (200 ppm) all zinc analyses were done by atomic absorption.

Alaska↗
USGS1978

Geochemical and generalized geologic map showing distribution and abundance of barium, arsenic, boron, and vanadium in stream sediments in the Chandalar Quadrangle, Alaska

This geochemical map shows the distribution and abundance of barium (Ba), arsenic (As), boron (B), and vanadium (V) in -80 mesh (177 micrometers) stream sediment samples in the Chandalar quadrangle, Alaska. The map is a part of a series of geochemical maps that together with the background information circular (Reiser and others, 1978) comprise the folio on the Chandalar quadrangle, Alaska. The data are plotted on a subdued base map showing the generalized geology, topography, and sample localities. Map symbols showing the ranges of metal values are indicated on the accompanying histograms and all values shown are considered anomalous. An explanation of sampling, preparation, analytical procedures, and geochemical raw data for all samples are discussed by O'Leary and others (1976). The -80 mesh (177 micrometers) stream sediment medium was used in this study because of the regional setting in the north-central Brooks Range. Given the rather restrictive time and manpower constraints the -80 mesh (177 micrometers) stream sediment combined with panned concentrates was determined to be the most economical and adequate medium in this case where clastic sediments are being derived from local bedrock. The study area is generally one of high relief with short fast-moving streams and broad glacial valleys. All samples were taken from active streams, as close to the center channel as possible. All sediments were considered to be locally derived. Care was taken, when sampling an obviously glaciated terrane, to sample above or upstream from morainal material, wherever possible. Most samples were taken in areas where bedrock was within 30 m of the sample site. Due to the poor sensitivity by spectrographic analysis for arsenic, 200 ppm (parts per million), all arsenic analyses were done by colorimetry.

Alaska↗