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Research about Idaho

Source-linked reports with geographic coverage including Idaho.

At least 1,027 records · Page 57Linked to original sources
USGS1960

Gravity survey in part of the Snake River Plain, Idaho — A preliminary report

During the early summer of 1959, a total of 1,187 gravity stations were occupied on the western part of the Snake River plain in Idaho. An area of 2,000 square miles extending from Glenns Ferry, Idaho, to Caldwell, Idaho, was covered with a station density of one station per two square miles. An additional 1,200 square miles of surrounding area, mainly from Caldwell, Idaho, to the Oregon-Idaho state line, was covered with a density of one station per seven square miles. The mean reproducibility of the observed gravities of these stations was 0.05 milligal, with a maximum discrepancy of 0.2 milligal. Gravity data were reduced to simple Bouguer values using a combined free-air and Bouguer correction of 0.06 milligal per foot. The only anomalies found with closure in excess of 10 milligals are two elongated highs, orientated northwest-southeast, with the northwestern high offset to the northeast by 10 miles. The smaller of these highs extends from Meridian, Idaho, to Nyssa, Oregon, and the larger extends from Swan Falls, Idaho, to Glenns Ferry, Idaho. The maximum value recorded is a simple Bouguer value of -66.5 milligals with respect to the International Ellipsoid. Gradients on the sides of these highs are largest on the northeast sides, reaching six milligals per mile in places. Graticule interpretations of a profile across the southeastern high using a density contrast of 0.3 gm per cubic centimeter indicate an accumulation of lava reaching a thickness of at least 28,000 feet. The Snake River investigation was made for the purpose of searching out, defining, and interpreting gravity anomalies present on the western part of the Snake River lava plain in Idaho. In particular, it was desired to further define gradients associated with the gravity high shown by the regional work of Bonini and Lavin (1957). It was not planned to cover any specific area, but rather to let the observed anomalies determine the course of the field work. The study was undertaken as part of a project on Volcanism and Crustal Deformation, supervised by L. C. Pakiser of the U.S. Geological Survey. Professor Rodgers of the Geophysics Department of the Colorado School of Mines acted as an advisor.

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USGS1958

Preliminary report on ground water in the Bonanza Lake area, Power and Blaine counties, Idaho

The investigation in the Bonanza Lake area of northwestern Power and southeastern Blaine Counties was made to determine the direction of ground-water movement and to ascertain the relation of the regional ground-water body to the Snake River. The surface of the area is nearly flat to gently rolling, and slopes to the west. Lake Channel, an abandoned channel of the Snake River, and a few volcanic cones modify the gentle relief. The climate is semiarid, the annual precipitation ranging from 10 to 15 inches. Most of the area is uncultivated and covered with sagebrush, the predominate vegetation. A significant amount of the area is dry farmed; about 500 to 650 acres is irrigated with ground water pumped from wells or from ponds in Lake Channel. The Bonanza area and vicinity are underlin by windblown deposits of Recent age (not shown on the geologic map); alluvium with admixed windblown material and black basalt, both also of Recent age; undifferentiated Snake River basalt, of Pliocene to Recent age; the American Falls lake beds and Cedar Butte basalt, or Pleistocene age; of the Raft Lake beds and Massacre volcanic and associated rocks, of Pliocene(?) age. The alluvium contains ground water at shallow depth, but because of its limited areal extent it is not an important aquifer, The Snake River basalt is the most important aquifer in the area and yields water to irrigation, domestic, and stock wells. Several springs discharge from the basalt into Lake Walcott. The Cedar Butte basalt is a major aquifer supplying water to a number of stock and domestic wells and to Bonanza Lake. Ground water moves southward and southwestward through the area from the Aberseen-Springfield tract on the northeast and possibly from the downstream end of American Falls Reservoir. Part of the ground water is discharged to the Snake River and Lake Walcott and part moves westward out of the area of the main ground-water body. The amount of ground water can not be determined from the data bow available. Data from dam-site borings and wells suggest the possibility that a part of the ground water in the area may be perched above the regional water table.

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USGS1958

Reconnaissance petrography of the Idaho batholith in Valley County, Idaho

The purpose of this report is to describe the rocks comprising a part of the Idaho batholith in west-central Idaho (see index map, Figure 1). The study is a by-product of an investigation of placer deposits containing radioactive minerals, monazite and euxenite, by the U. S. Geological Survey on behalf of the Division of Raw Materials of the U. S. Atomic Energy Commission (Mackin and Schmidt, 1956). Tracing of the valuable minerals to their source by panning of alluvium and residual soil made it evident that their distribution in the bedrock forms definite patterns roughly paralleling the west border of the batholith. The petrographic study was undertaken to clarify the relationships of the radioactive heavy minerals to the structure of the batholith, and for what light it might shed on the ultimate origin of these minerals.

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USGS1958

Records of springs in the Snake River valley, Jerome and Gooding Counties, Idaho, 1899-1947

Many springs and seeps discharge water from the north wall of the valley of the Snake River between Milner and Bliss, Idaho. These are fed by a large ground-water body lying east and north of the river, beneath the Snake River Plain. Much ground water is pumped on the plain, many irrigation wells having been drilled since 1946. Heavy withdrawal of ground water from wells may alter the discharge rates and regimens of the springs and may affect downstream flow of the river. For that reason, the historic record of discharge from the springs is an important part of the basis on which hydrologic changes can be determined. The records also would facilitate appraisal of the total groundwater resources of the Snake River Plain. This report brings together in a single volume all obtainable records for the period 1899-1947. The report also includes descriptive data and a brief history of work done. The springs occur in a 40-mile reach of the valley of the Snake River between Milner Dam and Bliss. Most are on the north side of the river but a few are on the south. The earliest measurements of record were made by F. S. Shirley and N. S. Dils, of the U. S. Geological Survey, in 1899. The next were by J. D. Stannard for the Idaho State Engineer and by Dils in 1902. Few measurements were made from 1903 to 1916. Somewhat more systematic measurements were made by the Geological Survey and by local agencies in 1917-20, 1923-25, and 1931, and at several intervals thereafter. In 1950 the Geological Survey began continuous, systematic measurements by installing and operating gaging stations on four representative springs and by making yearly direct measurements of all large springs. The recent records are not included in this report; they have been published yearly in a series of reports on stream discharge. The report includes lists of all published sources from which data were compiled, and cites many unpublished sources. The principal workers and agencies that have obtained records are listed also. The quality and accuracy of the compiled records, as might be expected, are not uniform, as the records were collected under varying circumstances, by many individuals, and according to changing or differing standards. The continuity is generally poor. Nevertheless, the compilation represents the base from which further work must start and is an extremely valuable record. It represents about 30 large springs and groups of springs, having discharge rates ranging from a fraction of a cubic foot per second to well over 1,000 cfs. Many smaller springs and seeps never have been measured. The fluctuation indexes for individual springs or groups range from 2 to 41 percent. The fluctuation index is the mean deviation of the discharge rate from the arithmetic mean, expressed as a percentage of the arithmetic mean. Although to some extent the indexes are a measure of the consistency of the record, they also seem to reflect actual differences in range of discharge, and they indicate that springs upstream in the Snake River valley fluctuate through a wider range than do those downstream. The fluctuations are rather slow, which reflects the equalizing influence of the large ground-water reservoir that supplies the springs.

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USGS1957

Ground-water possibilities south of the Snake River between Twin Falls and Pocatello, Idaho

The Snake River Plain and tributary valleys south of the Snake River between Twin Falls and Pocatello, Idaho (here called the South Side area), contain about 180,000 acres of irrigated land, of which 145,000 acres is irrigated with surface water and 35,000 is irrigated wholly or partly with ground water. The area also contains more than 200,000 acres of arable land that is idle or used only for grazing because it lacks irrigation water. Most of the surface-water supply is already used or reserved, and some land now irrigated needs supplemental water. The climate of the area ranges from semiarid on the Snake River Plain to subhumid on higher mountains. The average annual precipitation at lowland stations ranges from about 9 to 12 inches. The principal sources of ground water are extrusive volcanic rocks of silicic to intermediate composition, basalt, and sand and gravel. Ground water occurs commonly under artesian conditions in the silicic to intermediate volcanic rocks and in sand and gravel tongues and lenses in lake beds. Basalt and alluvium commonly contain unconfined water. The area of this report is divided into 13 roughly defined ground-water districts, some of which are further divided into subdistricts. The known geologic and hydrologic factors of each area are summarized and a preliminary appraisal is made of the ground-water resources in relation to land resources and to the regimen of streams. The current state of development, proposed new developments, and ground-water potential of each division are discussed. The Dry Creek district is the most intensively irrigated area in Idaho in which wells furnish the water supply. Ground water occurs under both artesian and water-table conditions. More than 53,000 acre-feet of ground water was pumped in 1954. There are large areas of undeveloped arable land in the district, but pumping in some parts of the district currently is approaching or surpasses the perennial yield of the ground-water reservoirs. The Golden Valley district contains considerable arable land but, owing to the relatively great depth to water and the generally poor yield of wells, the prospects for extensive ground-water development are not promising. In the Oakley district ground water is pumped from alluvium to supplement surface water and to bring new land into production. The ground water will be fully exploited within a few years if the present rate of development by individual landowners continues. The total area of nonirrigated land far exceeds the amount that could be irrigated with indigenous ground water. Both artesian and unconfined water occur in the Burley district. Most existing wells tap unconfined water in the southern part where there are still large tracts of idle arable land. Pumping lifts are rather high. The South Walcott district contains a considerable acreage of arable land and is underlain by excellent aquifers. The effect that heavy pumping would have on the flow of the Raft and Snake Rivers and on seepage from Lake Walcott is Taot well understood. Presumably substantial pumping would be feasible without direct deleterious effects. The Raft River basin, including the Elba and Almo-Yost subbasins, is the largest district in the South Side area. Ground water occurs in both unconfined and artesian aquifers. Possibly as much as 150,000 acres of dry land is irrigable, but the ground-water supply presumably is sufficient to irrigate only a few thousand acres in addition to the approximately 40,000 now irrigated with surface and ground water. Pumping of wells at some locations would deplete the base flow of the Raft River and would be competitive with surface-water use. The United States Bureau of Reclamation has started construction of the Michaud Flats Irrigation Project in the Western Michaud Flats district. The adopted reclamation plan is to irrigate about 10,000 acres, using surface water pumped from American Falls Reservoir and ground water pumped from wells. Ground water in part of the district is tributary to the reservoir. Withdrawals of ground water will be compensated in part by the return of waste water to the reservoir and to the Snake River. The Eastern Michaud Flats district contains more arable land and has better aquifers than the Western Michaud Flats district, but pumping might reduce noticeably the discharge of ground water to the American Falls Reservoir. The Bureau of Indian Affairs plans to develop about 13,600 acres of Indian land with water stored in Palisades and American Falls Reservoirs. Virtually nothing is known about ground-water conditions in the Arbon and Rockland Valleys and in several small areas such as the Basin district, the Albion basin, and along the northern border of the Sublett Range. Preliminary studies have been made in three areas, the Dry Creek, Raft River, and Western. Michaud Flats districts. None has been studied comprehensively. The available data for each district are summarized in tabular form. Further investigations in the area are needed and should include accurate hydrologic mapping. Studies are needed of the sources and amounts of groundwater recharge, of the effects of ground-water withdrawals on the total water supply, and of numerous related problems.

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USGS1957

Ground-water geology of the Bruneau–Grand View area, Owyhee County, Idaho

The Bruneau-Grand View area is part of an artesian basin in northern Owyhee County, Idaho. The area described in this report comprises about 600 square miles, largely of undeveloped public domain, much of which is open, or may be opened, for desert-entry filing. Many irrigation-entry applications to the Federal Government are pending, and information about ground-water geology is needed by local citizens and well drillers, by Federal agencies that have custody of the land, and by local and State agencies that administer water rights. The areal geology and ground-water conditions in the Bruneau-Grand View area seemingly typify several basins in southwestern Idaho, and this study is a step toward definition and analysis of regional problems in ground-water geology and the occurrence and availability of ground water for irrigation or other large-scale uses. Owyhee County is subdivided physiographically into a plateau area, the Owyhee uplift, and the Snake River valley. The Bruneau-Grand View area is largely within the Snake River valley. The climate is arid and irrigation is essential for stable agricultural development. Nearly all usable indigenous surface water in the area is appropriated, including freshet flow in the Bruneau River, which is used for power generation at the C. J. Strike Dam. However, with storage facilities additional land could be irrigated, and some land may be irrigated with Snake River water if suitable reclamation projects are constructed. Sedimentary and igneous rocks exposed in the area range in age from Miocene to Recent. The igneous rocks include silicic and basic intrusive and extrusive bodies, and the sedimentary rocks are compacted stream and lake sediments. The rocks contain economically important artesian aquifers; the principal ones are volcanic rocks in which ground water is imperfectly confined beneath sediments of the Idaho formation, thus forming a leaky artesian system. The altitude of the piezometric surface of the artesian water does not exceed about 2,700 feet above mean sea level. In some areas, where the land surface is below that altitude, the artesian system discharges water through springs and seeps and locally causes waterlogging and development of alkali soil. In chemical quality much of the water is unsuitable for irrigation and domestic use. The water contains a relatively moderate amount of dissolved solids, but the percent sodium and the concentration of fluoride are excessive for some uses. The quality of the water for irrigation ranges from excellent in the southern part of the artesian system to unsuitable in the northern part. All the artesian ground water that was sampled contained excessive amounts of fluoride. There is a substantial supply of undeveloped artesian water in the area, but sustained use of the water for irrigation may not be feasible unless provisions can be made for adequate soil drainage and soil amendment, because of the high percentage of sodium in the water. Detailed hydrologic and geologic study of the area should precede development.

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USGS1956

Geochemistry of sphalerite from the Star Mine, Coeur d'Alene district, Idaho

Forty sphalerite samples from the Star mine, Coeur d'Alene district, Idaho, and 19 sphalerite samples from other Coeur d'Alene mines have been quantitatively analyzed by spectrographic methods for Fe, Cu, Pb, Cd, Ga, Ge, In, Mn, Co, and Hg. The samples from the Star vein were collected over a strike length of 2,000 feet and a vertical distance of 5,300 feet.It is believed that Star mine sphalerite formed in equilibrium with Fe; consequently, following Kullerud's work, the Fe content may be used as a relative temperature scale. Relative Fe temperatures suggest that the lower portions of the Star ore body formed at lower temperatures than the upper portions of the ore body.Distribution of the minor elements in sphalerite is random within the ore body. Also, there is no correlation of Fe with minor elements other than Mn; therefore we believe temperature has had no influence on the distribution of minor elements, except Mn, in this ore body.The principal reason for this seems to be that equilibrium concentrations of the minor elements were not reached. Minor-element concentrations in sphalerite from the Coeur d'Alene district are similar to those in other districts throughout the world; consequently, the writers suggest that in general the minor-element content of sphalerite, other than perhaps Mn, cannot be an indicator of formation temperatures because equilibrium concentrations are rarely, if ever, attained.The average minor-element content in a district is probably that of the ore-forming solutions. Specific minor-element content in sphalerite is random.

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USGS1956

Ground water in the North Side Pumping Division, Minidoka Project, Minidoka County, Idaho

The U. S. Bureau of Reclamation proposes to irrigate about 64, 000 acres, largely in southern Minidoka County north and west of the Snake River, with ground water from 175 wells; 13, 650 additional acres would receive surface water pumped to a high-line canal from Lake Milner. More than 20,000 additional acres nearby is being developed by private capital. Completion of the Federal reclamation project will more than double the irrigated acreage in the North Side Division of the Minidoka Project. The area to be irrigated with ground water is at the south-central edge of the Snake River Plain adjacent to project lands that have been irrigated for many years with Snake River water.

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USGS1956

Preliminary report on the geology and deposits of monazite, thorite, and niobium-bearing rutile of the Mineral Hill district, Lemhi County, Idaho

Deposits of minerals containing niobium (columbium), thorium, and rare earths occur in the Mineral Hill district, 30 miles northwest of Salmon, Lemhi County, Idaho. Monazite, thorite, allanite, and niobium-bearing rutile form deposits in metamorphic limestone layers less than 8 feet thick. The known deposits are small, irregular, and typically located in or near small folds. Minor faults are common. Monazite generally is coarsely crystalline and contains less than one percent thorium. Rutile forms massive lumps up to 3 inches across; it contains between 5 and 10 percent niobium. Rutile occurs in the northwestern half of the district, thorite in the central and southeastern parts. Monazite occurs in all deposits. Allanite is locally abundant and contains several percent thorium. Magnetite and ilmenite are also locally abundant. A major thrust fault trending northwest across the map-area separates moderately folded quartzite and phyllitic rocks of Belt age, on the northeast, from more intensely metamorphosed and folded rocks on the southwest. The more metamorphosed rocks include amphibolite, porphyroblastic feldspar gneiss, quartzite, and limestone, all probably of sedimentary origin, and probably also of Belt (late Precambrian) age. The only rocks of definite igneous origin are rhyolite dikes of probable Tertiary age. The more metamorphosed rocks were formed by metasomatic metamorphism acting on clastic sediments, probably of Belt age, although they may be older than Belt. Metamorphism doubtless was part of the episode of emplacement of the Idaho batholith, but the history of that episode is not well understood. The rare-element deposits show no evidence of fracture-controlled hydrothermal introduction, such as special fracture systems, veining, and gangue material. They may, however, be of hydrothermal type. More likely they are metamorphic segregations or secretions, deposited in favorable stratigraphic and structural positions during regional metamorphism.

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USGS1955

Comments on minor elements in pyrrhotite [Idaho]

The cobalt and nickel content of pyrrhotite from the Highland-Surprise mine, Coeur d'Alene district, Idaho, was determined by spectrographic methods. The Co and Ni values fall within the ranges of values found by other investigators. Comparison of the distribution of Co and Ni in the Highland-Surprise ore shoot with the distribution of these elements in the Silberberges, Germany, and Noranda, Canada, ore shoots suggests that caution must be used in the determination of relative temperature conditions in ore shoots by means of studies of minor elements, principally because it seems likely that equilibrium concentrations are commonly absent.

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