USGS Science⌕ Search

SEARCH · USGS Science

Results for “Journal of Geological Research”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources

Metamorphic forsterite and diopside from the ultramafic complex at the Tuolumne River, California

Metamorphic forsterite (Fo=98) and diopside (Wo:En:Fs=48.5:49.5:2.0) have been, formed from serpentinite within intensely sheared zones in the large ultramafic complex at the Tuolumne River near Sonora, Calif. Bladelike grains of forsterite are elongate, parallel to c , and have prominent idiomorphic faces developed in (010). Metamorphic diopside occurs as small grains, free of inclusions, in rocks containing forsterite. The formation of forsterite and forsterite +diopside in serpentinite probably took place by the following reactions: antigorite+magnesite→2 forsterite+ fluid 3 antigorite+calcite→4 forsterite+diopside+fluid Iron derived from the primary olivine and chromite has been oxidized almost entirely to magnetite and may be treated as an indifferent or accessory component. Stratigraphic reconstruction indicates that the total load pressures probably did not exceed 3 kilobars. At these pressures, the reaction should take place between 400° and 500°C with a fluid composition ranging from nearly pure H 2 O to less than 5 mole percent CO 2 . The restriction of forsterite and forsterite-f-diopside to shear zones may be attributed to the presence of carbonate in the rock prior to metamorphism and to the dilution of a CO 2 -bearing fluid phase by water coming from outside the area of the reaction.

California↗

Mercury in oil shale from the mahogany zone of the Green River formation, eastern Utah and western Colorado

Mercury has been reported in concentrations as high as 4 parts per million from oil shale in the Green River Formation near the Federal oil-shale prototype lease-tracts U-a and U-b in eastern Utah. This high concentration of mercury if present throughout a minable zone, would be of concern in commercial oil-shale operations processing large volumes of shale. Using an improved analytical method, surface samples from eastern Utah previously reported to contain high concentrations of mercury were reanalyzed, and an additional 183 drill core samples from the Mahogany zone and adjacent beds were analyzed. The reanalyzed samples averaged slightly more than 0.35 ppm mercury and the drill-core samples averaged 0.37 ppm. The products from a Fischer assay of 100-gram sample of oil shale, found to yield 35 gallons pier ton of oil and 43 ppm of mercury, were analyzed for their mercury content. The spent shale contained only 2 percent of the total mercury in the assay products and the gas fraction contained about 58 percent.

Colorado, Utah↗

Activity-product constants of brucite from 10 degrees to 90 degrees C

The activity-product constant of brucite, K B = [Mg 2+ ][OH - ] 2 (where the brackets denote activities), was determined experimentally at 10°, 25°, 40°, 55°, 70°, and 90°C. The values obtained for -log K B are 10.89±0.16 (10°), 10.88±0.10 (25°), 10.90±0.10 (40°), 10.90±0.10 (55°), 10.99±0.14 (70°), and 11.10±0.14 (90°). Using National Bureau of Standards Technical Note 270 data for the ions, the free energy of formation (Δ G ° t ) at 25° for brucite is 831.486 joules per mole ( 198,730 cal mol -1 ). Using data compiled by R. A. Robie and D. R. Waldbaum in 1968 for the ions, this Δ G ° t is -823,323 J mol -1 (-198,930 cal mol -1 ). Values of log KB are also calculated for the temperature range 0° to 200°C, by using thermochemical data listed by V. B. Parker, D. D. Wagman, and W. H. Evans in 1971 and E. G. King, M. J. Ferrante, and L. B. Pankratz in 1975 and the partial molal heat capacities estimated by C. M. Criss and J. W. Cobble in 1965. The experimental values are similar to the calculated values, especially at lower temperatures.

Journal of Research of the U.S. Geological Survey↗

Petrology of the Precambrian intrusive center at Lake George, southern Front Range, Colorado

The intrusive center at Lake George, at the western margin of the Pikes Peak batholith (1030 m.y.) of central Colorado, contains rocks of both the potassic and sodic differentiation trends recognized in the batholith. Finer grained variants of the Pikes Peak Granite initially formed a texturally zoned stock 8 kilometers in diameter that cut the dominant coarse-grained granite of the batholith. This granite stock (potassic trend) was later intruded by partial ring dikes of quartz syenite to fayalite granite and by a central stock of quartz syenite to syenomonzonite (sodic trend). Xenoliths of alkali gabbro, diorite porphyry, and granodiorite are included within rocks of both differentiation trends. All major rock types of the intrusive center are thought to be derivatives of alkali basaltic magma from the mantle, modified by fractional crystallization and reaction melting of crustal rocks. The geometry of the intrusive center was controlled by ring-dike/cauldron-subsidence mechanisms.

Colorado↗

Removal of fluorine and lithium from hectorite by solutions spanning a wide range of pH

One-gram samples of hectorite were treated with 40 millilitres each of hydrochloric acid (6 N ), acetic acid (4.5 N ), distilled water, natural seawater, sodium chloride (0.6 N ), and sodium hydroxide (2.5 N ) for 10 days in stoppered plastic centrifuge tubes. X-ray diffraction patterns show that the structure was virtually destroyed by the hydrochloric and acetic acids. Analyses of the supernatant liquids were made to determine amounts of the elements removed by the various treatments. All treatments removed at least some SiO 2 , MgO, CaO, Li 2 O, and F. The acids removed most of the lithium and magnesium after 3 days. The fluorine and the magnesium released by the acetic acid began to form sellaite (MgF 2 ). After 5 days, sufficient sellaite was produced to be discernible by X-ray diffraction. The loss of silica from the sample when it was treated with sodium hydroxide amounted to about 10 percent of the total sample.

Journal of Research of the U.S. Geological Survey↗

Effects of dredged channels on trace-metal migration in an estuary

Determination of trace-metal levels in the sediments of the Matagorda Bay system revealed anomalously high mercury values. The distribution of the mercury-rich sediment deposits is the result of the sedimentological regime of the bay system produced by the tidal currents in the dredged channel. According to this model, the oxygenated open gulf water pushed into the bay by tidal currents activates the mercury and reintroduces it into the sediment regime of the bay in an area where the turbidity maximum is most prevalent. Within this region, the absorption sites are at a maximum, tying up the mercury. The mercury-enriched suspended material is then transported and deposited according to the hydraulic regime within the bay system.

Texas↗

Igneous and metamorphic petrology of the southwestern Dana Mountains, Lassiter Coast, Antarctic Peninsula

The southwestern Dana Mountains of the southern Antarctic Peninsula are underlain by the western part of a composite concentrically zoned Upper Cretaceous batholith consisting largely of granodiorite. The granodiorite (felsic phase) was intrusive into older heterogeneous gabbro-diorite (mafic phase) which makes up the margin of the batholith. Flat-lying pegmatite bodies and abundant inclusions, roof pendants, and septa of metasedimentary rocks and gabbrodiorite suggest that the granodiorite lies near the roof of the batholith. Petrography, chemistry, field relations, and radiometric age dates indicate that the batholith is part of the Andean intrusive suite, a suite of calc-alkaline plutonic rocks that crops out extensively throughout the Antarctic Peninsula and Chilean and Patagonian Andes. Textural features, mineralogy, and chemical data indicate that both phases of the batholith in the southwestern Dana Mountains have been contaminated by assimilation of the Latady Formation, an Upper Jurassic sequence of shale, siltstone, and sandstone that underlies large parts of the southern Antarctic Peninsula. Composition of the granodiorite also has been modified by assimilation of lesser amounts of the gabbro-diorite phase. Such contaminated plutonic rocks occur in several places in the northern Antarctic Peninsula; the batholith in the southwestern Dana Mountains represents the southernmost exposures of contaminated igneous rocks known from the Antarctic Peninsula. Hornblende andesite dikes cut both the mafic and felsic phases of the batholith. Chemical data imply that the dikes represent small amounts of mafic material remobilized by intrusion of the granodiorite. During the austral summers of 1969

Antarctic Peninsula, Dana Mountains, Lassiter Coas↗

Implications of the petrochemistry of palladium at Iron Canyon, Lander County, Nevada

Approximately one-half of the 270 samples from the Iron Canyon area, Nevada, analyzed for platinum-group metals, contain measurable amounts of palladium in the 0.001- to 0.02-part per million range with an average of 0.0034 ppm. The rocks include lower Paleozoic sedimentary and volcanic rocks, Tertiary granitic porphyries, and breccia, all of which exhibit various degrees of hydrothermal alteration. Fault-related iron oxides and vein quartz are also present. The area lies astride the outermost fringes of the zone of dispersed alteration visible in outcrops around the middle Tertiary porphyry-copper system at Copper Canyon, Nevada. At Iron Canyon, the palladium concentrations greater than 0.003 ppm seem to be spatially related to the Butte fault zone, a north-striking fault system active during the time of porphyry-type mineralization. Palladium contents vary directly with those of mercury, arsenic, strontium, silver, lanthanum, and boron, as well as with lead, gold, and copper in obviously metallized rocks. This relation probably reflects the mobility of palladium during porphyry-type mineralization. However, our study failed to document conclusively the overall introduction of palladium during mineralization. Among the likely sources of palladium are the lower Paleozoic volcanic rocks or fluids equilibrated with magma (s) associated with the middle Tertiary porphyries.

Nevada↗

Possibility of triggering earthquakes by injection of radioactive wastes in shale at Oak Ridge National Laboratory, Tenn.

Most investigators generally agree that the conditions for producing earthquakes by fluid injection through wells and by reservoir construction are (1) the presence of an underlying rock that is stressed to the verge of fracturing by tectonic stresses and (or) is on the brink of sliding on pre-existing fault planes, (2) the presence of potentially active faults(s), and (3) an increase of pore pressure in the rock caused by fluid injection or seepage from reservoir (s), which is probably the triggering force. The mechanism of disposal of radioactive wastes in shale by grout injection and hydraulic fracturing, which has been used at ORNL (Oak Ridge National Laboratory, Tenn.) is different from injection of fluid. The injected grout is in its liquid phase only during the injection period and, it is to be hoped, is confined in the hydraulically induced bedding-plane fractures. The grout is then allowed to solidify under pressure after termination of the injection, and, after solidification, it becomes an integral part of the shale. Significant characteristics of the disposal method and the site are as follows: (1) Because of the low permeability of shale and high viscosity of the injection grout, pore pressure in the rock, beyond the region of induced fractures, does not increase due to the injections; the injected grout enters newly formed bedding-plane fractures, (2) the injection site is free of local faults and of major interconnected joints and fractures; accordingly, injected grout in its liquid state is expected to be confined principally in the induced nearly horizontal bedding-plane fractures, and (3) due to low tensile strength along shale bedding planes, the energy needed to induce bedding-plane fractures is small; experiments made at ORNL indicate that the energy released during hydraulic fracturing in shale is so small that seismic signals generated by grout injections cannot be differentiated from ambient ground vibrations. In view of the fact 'that an increase of pore pressure in rock (the triggering force) and association with potentially active fault (s) do not occur at the proposed site at ORNL and that the disposal method does not produce an increase in pore pressure, it can reasonably be concluded that neither the method nor the site has the characteristics for triggering earthquakes during and after grout injections.

Tennessee↗

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↗

The quantitative determination of chlorophylls A and B from freshwater algae without interference from degradation products

Chlorophyll was efficiently extracted from freshwater algae with dimethyl sulfoxide. The extract was chromatographed on commercially available thin-layer cellulose sheets, 2 percent methanol and 98 percent petroleum ether being used as the solvent. Chlorophylls a and b , and phaeophytins a and b were cleanly separated from each other and other degradation products. No artifacts were formed. Recoveries of chlorophylls a and b were 98 and 96 percent as measured by spectrophotometry or fluorometry.

Journal of Research of the U.S. Geological Survey↗

Phytoplankton distribution and primary productivity in Donner Lake, California

Donner Lake is an unenriched system in the Lake Tahoe basin of the Sierra Nevada of California. The lake has a surface area of 1.5 square miles (3.9 square kilometres) and a drainage area of 14 mi 2 (36 km 2 ). The maximum depth is about 200 feet (60 metres). Between May and December 1973, the phytoplankton in Donner Lake was represented by 6 classes and at least 25 genera. The dominant green alga was the desmid Cosmarium staurastroides , which comprised about 25 percent of the total phytoplankton collected. The dominant diatom was Asterionella formosa , which comprised about 13 percent of the total phytoplankton. Blue-green algae were represented by Chroococcus sp., but were never abundant and constituted only 1.5 percent of the total organisms sampled. The depth of the euphotic zone from May through September ranged from 35 to 93 feet (11 to 28 metres). Thermal stratification was strong throughout the summer with a maximum temperature difference between the surface and bottom water of 17° Celsius in July. Average phytoplankton concentrations were often greater below the euphotic zone than in the euphotic zone. This pattern of phytoplankton distribution is similar to nearby Lake Tahoe and other oligotrophic lakes. Three primary productivity measurements were made during the study using the carbon-14 method. The primary productivity values were 93, 64, and 56 milligrams of carbon per cubic metre per day for May 17, August 13, and October 16, respectively. The productivity profile in May was shallow and unimodal, whereas the August and October profiles were deeper and biomodal. Dissolved-oxygen concentrations were maximum at the same depths as maximum primary productivity. On the basis of phytoplankton types and their vertical distribution patterns, and upon primary productivity measurements, Donner Lake is considered oligotrophic.

California↗

Pleistocene rhyolite of the Mineral Mountains, Utah: Geothermal and archeological significance

Little-eroded rhyolitic tuffs, flows, and domes extend over about 25 km 2 along the western side of the Mineral Mountains, southwestern Utah, which is along the eastern edge of the Roosevelt KGBA (Known Geothermal Resource Area). Initial eruptions resulted in two low-viscosity lava flows of nonporphyritic rhyolite. These were followed by bedded pumice falls and nonwelded ash flows. The youngest activity produced at least nine viscous domes and small lava flows of rhyolite that contain 1-5 percent phenocrysts of quartz, plagioclase, sodic sanidine, and biotite; distinction between domes and eroded flow segments locally is difficult. Potassium-argon ages indicate that all the rhyolite of the Mineral Mountains was erupted between 0.8 and 0.5 m.y. ago. The rhyolite rests on dissected granite of the Mineral Mountains pluton, the largest intrusion in Utah, which has yielded published K-Ar ages of 9 and 15 m.y. A small older dissected rhyolite dome, about 8 m.y. old, occurs just west of the range front. Whether the young ages of the pluton represent time of intrusion or of later reheating, they, in conjunction with the Pleistocene rhyolite in the Mineral Mountains, do indicate a major late Cenozoic thermal anomaly, the size and age of which is significant to evaluation of the Roosevelt KGRA. The rhyolite is also the only known source of implement-grade obsidian in the southwest between eastern California and northern New Mexico.

Utah↗

The heat capacities of Calorimetry Conference copper and of muscovite KAl2(AlSi3)O10 (OH)2, pyrophyllite Al2Si4O10(OH)2, and illite K3(Al7Mg)(Si14Al2)O40(OH)8 between 15 and 375 K and their standard entropies at 298.15 K

The heat capacities of Calorimetry Conference copper and of muscovite, pyrophyllite, and illite were measured between 15 and 375 K using an adiabatic calorimeter. Tables of the thermodynamic functions C° p .( H° T — H° O ) /T , ( G° T —H° O ) /T , and S° T —S° O are presented for these phases at integral temperatures from 0 to. 370 K. At 298.15 K (25.0°C), S° T —S° O is 33.12±0.06, 287.7±0.6, 239.4±0.4, and 1,104.2±0.6 J/(mol•K) for copper, muscovite, pyrophyllite, and illite, respectively. The operation of a semiautomatic data-acquisition system for calorimetric measurements at low temperatures is also described, together with a description of a miniature calorimeter having a novel closure seal.

Journal of Research of the U.S. Geological Survey↗

Geothermal flux through palagonitized tephra, Surtsey, Iceland: The Surtsey temperature-data-relay experiment via Landsat-1

The net geothermal flux through palagonitized basaltic tephra rims of the Surtur I and Surtur II craters at Surtsey, Iceland, in 1972, is estimated at 780 ±325 μ cal cm -2 s -1 , indicating a decline since 1969 when a flux of 1,500 μ cal cm -2 s -1 was estimated. Heat flux in this range characterizes the postvolcanic environment on Surtsey in which the subaerial palagonitization of basaltic tephra is associated with mass transfer of hydrothermal vapor, either of meteoric or sea-water origin, only a few years after cessation of eruptive activity. The flux estimation is the result of the Surtsey data-relay experiment via Landsat-1 which was carried. out in several phases. Successful field installation and test transmissions demonstrated the feasibility of repetitive long-distance (that is, 4,800-km) data transmission and reception from a volcanic environment in Iceland via the Landsat Data Collection System. Temperature data were transmitted for a 38-day period in November and December 1972. A near-surface vertical gradient of 69.4 °C/m was obtained, suggesting a mixed mechanism of heat transfer, partitioned between conduction and convection. Comparison of four methods for estimating fluxes between 500 and 1,500 μ cal cm -2 s -1 , using temperature data derived from the Data Collection Platform, suggests that, where the only temperature available are from the surface and a depth of 1 m, methods of estimating the net geothermal flux from examination of spectral radiance are superior to methods that assume dominant convection or conduction. A computerized thermal-modeling technique to construct parametric diurnal surface-temperature curves is particularly applicable. Flux-estimation methods that assume dominant convection or conduction are limited by the lack of temperature data at greater depths and lack of knowledge of the exact energy partition.

Surtsey↗

Gravity studies in the Carolina slate belt near the Haile and Brewer mines, north-central South Carolina

The Bouguer gravity map of part of the Carolina slate belt near the Haile and Brewer mines in South Carolina shows anomalies related to rock units. The most conspicuous of the anomalies coincide with coarse-grained granitic plutons. Mathematically calculated models using an iterative three-dimensional solution of the gravity anomalies show that these plutons are steep-sided intrusive bodies that constrict at depth to small pipes or roots. The plutons are emplaced in and are probably largely confined to a unit of volcaniclastic rocks. The volcaniclastic rocks are probably 6,000 m to 10,000 m thick and similar in composition to those exposed in the vicinity of the plutons.

South Carolina↗

Metagraywacke in the Salinian Block, central Coast Ranges, California: And a possible correlative across the San Andreas Fault

The schist of Sierra de Salinas is a monotonously homogeneous biotite quartzofeldspathic schist with minor amounts of quartzite, amphibolite, and marble that forms a northwest-trending outcrop belt that strikes across parts of the Santa Lucia and Gabilan Ranges and is traceable further south in the subsurface to where it is presumably cut off by the San Andreas fault zone. Chemical composition of the schist is similar to that of "average" graywackes. This large and monotonous terrane of metagraywacke is anomalous in the Salinian block, where a great variety of metamorphic rocks is the general rule. The age of the schist is not known, but it has been intruded by granitic rocks of presumably mid-Cretaceous age. Although it contains somewhat greater amounts of admixed quartzite, amphibolite, and marble, the schist of Portal-Bitter Ridge (Pelona Schist?), on the east side of the San Andreas fault and west of Palmdale, is nevertheless modally and chemically similar to the schist (metagraywacke) of Sierra de Salinas, and I suggest that the two terranes are correlative and once were contiguous.

California↗