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Henry V. Alminas

Publications and source records attributed to Henry V. Alminas.

15 recordsLinked to original sources
USGS1979

Background information to accompany folio of geologic, mineral resource, geochemical, aeromagnetic, and gravity maps of the Hillsboro and San Lorenzo quadrangles, Sierra and Grant Counties, New Mexico, with sections on geochemistry and geophysics

The Hillsboro and San Lorenzo 15-minute quadrangles of southwestern New Mexico have been mapped at a 1:48,000 scale and selected mineralized areas within these quadrangles have been mapped in greater detail. This area of about 550 mi2 (1,424 km2) is within the southern part of the Black Range and includes much of the Mimbres Mountains and parts of the adjoining Black Range Primitive area. The region is highly mineralized with Laramide (75.1 ? 2.5 m.y.) and middle Tertiary (about 32 to 35 m.y.) intrusions providing the source for much of the base- and precious-metal mineralization. The porphyry copper deposit at Copper Flat is a subvolcanic Laramide quartz monzonite stock that was intruded into a thick section (>2,700 ft or >823 m) of Upper Cretaceous andesite. Numerous gold-bearing veins radiate from the central quartz monzonite stock, and locally offset a radial system of quartz latite dikes. Gold-bearing veins, chiefly along the south and east periphery of the stock, have provided the source for both gold lode and placer deposits. The middle Tertiary rhyolitic plugs, stocks, and dikes have intruded a dominantly carbonate section of Paleozoic sediments and bedding replacement deposits of zinc, lead, and copper are closely associated with tactite in the Carpenter (Swartz) mining district. The rich oxidized silver deposits of the Kingston district are largely fault controlled and a metallizing pluton is not present at the surface outcrop. Some of the silver-bearing base-metal veins in the Kingston district contain rhodochrosite, rhodonite, and alabandite and the highly oxidized parts of these veins have been mined for manganese ore. Very minor amounts of tungsten, as scheelite, occur in thin tactite zones along Tank Canyon, at the Silver Queen claims near Kingston, and at the Silver Tail group of mines along Pierce Canyon.

New Mexico↗
USGS1978

RFM (relative fraction magnitude): program explanation and computer program listing

The RFM (relative fraction magnitude) program is proposed as an aid in the estimation of depth to ore-mineral concentration. This estimate is based on the determination of the relative position of the sampled surface plane within the zonational framework of a hydrothermal sulfide mineralization. The program requires analytical data on two sample fractions collected at the same localities. The first of these must selectively concentrate iron and manganese oxides (exclusive of magnetite) and, the other, the sulfides and their oxidized zone derivatives.

Open-File Report↗
USGS1976

Oxalic-acid leaching of rock, soil, and stream-sediment samples as an anomaly-accentuated technique

In many instances total-rock and sieved-soil and stream-sediment samples lack the sensitivity and contrast required for reconnaissance exploration and necessary in the search for blind ore deposits. Heavy-mineral concentrates incorporate the required sensitivity and contrast but are overly expensive for two reasons: time-consuming sample preparation is required to obtain them, and they cannot be easily derived from all bulk-sample types. Trace-metal-content comparisons of the oxalic-acid-leachable portions with heavy-mineral concentrates show that the leachates are equal to the heavy-mineral concentrates in sensitivity and contrast. Simplicity of preparation and the resultant cost savings are additional advantages of this proposed method.

Open-File Report↗
USGS1975

Soil anomalies associated with Cu-Ni mineralization in the South Kawishiwi area, northern Lake County, Minnesota

Geochemical sampling in the contact zone between the Giants Range Granite and the Duluth Gabbro Complex along the South Kawishiwi River indicates the presence of extensive soil anomalies associated with the known Cu-Ni-Co-Ag mineralization in the basal part of the Duluth Gabbro Complex. A close spatial relationship was found between the ore bodies and associated anomalies, despite the fact that the parent material of the sampled soils was glacial overburden that mantles the area to a depth of 0-50 feet. The <74 mesh fraction of B-horizon soils was found to be an effective sample type for geochemical exploration in this area. Trace metals are believed to be held primarily by the clay-size hydrated iron oxides and manganese oxide, which are somewhat enriched in the fine fraction of the B-horizon soils.

Minnesota↗
USGS1972

A geochemical study of the Rio Pantanos area, Department of Antioquia, Colombia preliminary report

Geochemical sampling in the Western Cordillera has delineated an 18 km 2 area anomalous in copper, molybdenum, and silver. Highly anomalous metal contents are found in stream sediment, soil, and outcrop samples collected within this area. The area is underlain by intrusive granodiorite to quartz diorite that has porphyritic and granitoid phases. Most of the outcrop samples contain disseminated pyrite, chalcopyrite, and bornite. A geochemical reconnaissance sampling program in the Western Cordillera, formulated by Andros Jimeno V., Director, Instituto National de Investigaciones Geologico-Mineras (INGEOMINAS), and Earl M. Irving, U. S. Geological Survey (USGS) Chief of Party in Colombia, was carried out from 1969 to 1971 by geologists of the INGEOMINAS office in Medellin. This work was part of a cooperative program of INGEOMINAS and the USGS sponsored by the Government of Colombia and the Agency for International Development, U. S. Department of State. Seventeen generally east-trending traverses were completed across the Western Cordillera. These traverses, generally paralleling major drainages, cross the range at intervals of 10 to 30 km.

Open-File Report↗