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At least 73 records · Page 4

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DOE OSTI2021

2019 Groundwater Monitoring Report Project Shoal Area: Subsurface Corrective Action Unit 447

The Project Shoal Area is a site in Nevada where an underground nuclear test was conducted in 1963. It later came to be known as the Shoal, Nevada, Site. Surface contamination at the site has been remediated, but investigation of groundwater contamination resulting from the test is still in the corrective action process. Annual sampling and water-level monitoring are conducted as part of the subsurface corrective action strategy, which has focused on revising the site conceptual model and evaluating the adequacy of the monitoring well network. It has also included enhancements to the monitoring well network to address uncertainties in the groundwater flow direction and the cause of rising water levels in site wells west of the shear zone since the first hydrologic characterization (HC) wells were installed in 1996. Revisions to the site conceptual model and enhancements to the monitoring strategy were provided to Nevada Division of Environmental Protection (NDEP) in the Addendum to: Corrective Action Decision Document/Corrective Action Plan (CADD/CAP) for the Subsurface Corrective Action Unit 447 Shoal, Nevada, Site. NDEP approved the addendum to the CADD/CAP, which included an expanded contaminant boundary and compliance boundary for the site.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2024

2024 Update of Comprehensive Review of Multi-arm Caliper Data for the Big Hill SPR Site

The Big Hill SPR site has a rich data set consisting of multi-arm caliper (MAC) logs collected from the cavern wells. This data set provides insight into the on-going casing deformation at the Big Hill site. This report summarizes the MAC surveys for each well and presents well longevity estimates where possible. Included in the report is an examination of the well twins for each cavern and a discussion on what may or may not be responsible for the different levels of deformation between some of the well twins. The report also takes a systematic view of the MAC data presenting spatial patterns of casing deformation and deformation orientation in an effort to better understand the underlying causes. The conclusions present a hypothesis suggesting the small-scale variations in casing deformation are attributable to similar scale variations in the character of the salt-caprock interface. These variations do not appear directly related to shear zones or faults. In addition, the deformation orientation shows no preferred directionality. This 2024 edition of this report represents an update to the original, 2023 edition. The updates primarily focus on the inclusion of MAC log data run since the December 2021 threshold date for the original report, but some new analyses are also included.

58 GEOSCIENCES↗

NASA NTRS1973

Recognition of the geologic framework of porphyry deposits on ERTS-1 imagery

The author has identified the following significant results. Preliminary analysis of a mosaic composing 20 individual ERTS-1 frames that covers most of Nevada and western Utah reveals both new and old structural features. Three separate provinces, the Basin and Range, the southern extension of the Columbia River Plateau volcanics, and the western edge of the Colorado Plateau are easily distinguishable. A west-northwest cross or transverse structural trend, the Las Vegas Shear zone, is present in the region running from the Sierra Nevada to Lake Mead. The Sevier, Hurricane and Grand Wash faults that define the Wasateh-Jerome structural zone, can be traced further on the ERTS-1 imagery than on existing tectonic maps. By use of a stereo viewer on the side-lap coverage of ERTS-1 imagery, it is possible in some instances to determine the direction of sedimentary beds, enabling anticlines and synclines to be mapped. Other geologic features, faults, direction of throw on faults, recent basalt flow contacts with older rhyolitic tuffs, volcanic cones, and subsidences can also be mapped.

Wilson, J. C.↗

NASA NTRS1973

Utilizing ERTS-A imagery for tectonic analysis through study of Big Horn Mountains region

The author has identified the following significant results. MSS scene 1085-17294 of the Big Horn region has been subjected to detailed structural analysis. Band 7 is particularly good for revealing structural and drainage patterns because of enhance topographic detail and the subdued vegetational contrasts. Considerable stereo coverage through sidelap with adjoining scenes adds to the effectiveness of the study and has been used on both positive transparencies and enlarged prints. Negative prints of Band 7 positive transparencies have proven to be much more useful than positive prints because the higher resolution of the positive transparencies can be maintained. The Bighorn Mountains are crisscrossed by a number of prominent topographic linears, most of which can be correlated with known fault and shear zones in the Precambrian crystalline core. Many of these do not appear to continue into the flanking sedimentary rocks and a few that do (Tensleep, Tongue River lineaments) are very difficult to trace farther out into the basins. The Tongue River lineament, long a source of speculation and uncertainty as to its existence, appears as a very prominent discontinuity in the imagery.

Hoppin, R. A.↗

NASA NTRS1973

Studies of the inner shelf and coastal sedimentation environment of the Beaufort Sea from ERTS-1

The author has identified the following significant results. The particulate transport processes involved in the movement of surficial waters were examined using secchi disc readings, light attenuation coefficients, and particulate weights from filtration. Observations gathered during the summers of 1971 and 1972 indicate a remarkable difference in particulate matter and turbidity between the two years. ERTS-1 imagery during August 1972 showed turbid water along the northern Alaska coast. The uniformity of distribution of the turbid water and the fact that the river discharge is low at this period suggest that the turbidity is related to causes other than river effluent. Studies indicate that wave action is a more significant factor influencing particulate transport than believed heretofore. The boundary between the essentially immobile shorefast ice and the moving pack ice has been plotted from several ERTS-1 images and found to occur fairly consistently along the 20 meter contour. Considering the vast difference in the amount of ice movement shoreward and seaward of this boundary, ice-bottom action should also be different on either side of this boundary and for that matter at the shear zone that develops along the boundary.

Reimnitz, E.↗

NASA NTRS1973

Structural interpretations based on ERTS-1 imagery, Bighorn Region, Wyoming-Montana

Structural analysis is being carried out on bands MSS 5 and 7 of scene 1085-17294. Geologic strucutre is primarily revealed in the topographic relief and drainage. Topographic linears are particularly well developed in the bighorn uplift. Many of these occur along known faults and shear zones in the Precambrian core; several have not been previously mapped. These linears, however, do not continue into the younger rocks of the flanks or do so in a much less marked manner than in the core. Linears are far less abundant in the basin or are manifested only in very subtle tonal contrasts and somewhat straight drainage segments. Some of the linears are aligned along trends previously postulated on the basis of surface mapping to be lineaments. The imagery reveals little or no evidence of strike-slip displacements along these lineaments.

Hoppin, R. A.↗

NASA NTRS1974

Structural lineaments in the southern Sierra Nevada, California

The author has identified the following significant results. Several lineaments observed in ERTS-1 MSS imagery over the southern Sierra Nevada of California have been studied in the field in an attempt to explain their geologic origins and significance. The lineaments are expressed topographically as alignments of linear valleys, elongate ridges, breaks in slope or combinations of these. Natural outcrop exposures along them are characteristically poor. Two lineaments were found to align with foliated metamorphic roof pendants and screens within granitic country rocks. Along other lineaments, the most consistant correlations were found to be alignments of diabase dikes of Cretaceous age, and younger cataclastic shear zones and minor faults. The location of several Pliocene and Pleistocene volcanic centers at or near lineament intersections suggests that the lineaments may represent zones of crustal weakness which have provided conduits for rising magma.

Liggett, M. A.↗

NASA NTRS1980

Report on JANNAF panel on shotgun/relative quickness testing

As the need for more energetic solid propellants continues, a number of problems arises. One of these is the tendency of high energy propellants to transition from burning (deflagration) to detonation in regions where the propellant is present in small particle sizes; e.g., in case bonding areas of a motor after a rapid depressurization causes a shear zone at the bond interface as the stressed propellant and motor case relax at different rates. In an effort to determine the susceptibility of propellants to high strain rate break up (friability), and subsequent DDT, the propulsion community uses the shotgun/relative quickness test as one of a number of screening tests for new propellant formulations. Efforts to standardize test techniques and equipment are described.

Gould, R. A.↗

NASA NTRS1981

Analysis of Jamaican lineaments visible in Seasat-SAR imagery

Three digitally correlated Seasat SAR frames of Jamaica are used to examine the fault-related topography of the island. The major fault-controlled lineaments visible in the imagery are described, and some generalizations are made with respect to the recent tectonics of Jamaica. It is suggested that: (1) the island of Jamaica may represent the original position of a bend or discontinuity in the northern Caribbean Plate boundary; (2) the present tectonic regime may indicate the complex modification of a regional stress field at a discontinuity in an otherwise linear shear zone; (3) the island represents a tectonically maintained mass excess; and (4) the observed rapid uplift along the island's north coast may be related to compression-induced reverse faulting.

Dixon, T. H.↗

NASA NTRS1985

Computer studies of baroclinic flow

Programs necessary for computing the transition curve on the regime diagram for the atmospheric general circulation experiment (AGOE) were completed and used to determine the regime diagram for the rotating annulus and some axisymmetric flows for one possible AGOE configuration. The effect of geometrical constraints on the size of eddies developing from a basic state is being examined. In AGOE, the geometric constraint should be the width of the shear zone or the baroclinic zone. Linear and nonlinear models are to be used to examine both barotropic and baroclinic flows. The results should help explain the scale selection mechanism of baroclinic eddies in the atmosphere experimental models such as AGOE, and the multiple vortex phenomenon in tornadoes.

Gall, R.↗

NASA NTRS1985

Field Measurements of the 1983 Royal Gardens Lava Flows, Kilauea Volcano, and 1984 Mauna Loa Lava Flow, Hawaii

Theoretical models used in the remote determination of lava flow rheology and compositions rely on estimates of such geometric and flow parameters as volume flow rates, levee heights, and channel dimensions, as well as morphologic and structural patterns on the flow surfaces. Quantitative measures of these variables are difficult to obtain, even under optimum conditions. Detailed topographic profiles across several Hawaiian lava flows that were carefully monitored by the U.S. Geological Survey during their emplacement in 1983 were surveyed in order to test various flow emplacement models. Twenty two accurate channel cross sections were constructed by combining these profiles with digitized pre-flow topographic measurements. Levee heights, shear zone widths, and flow depths could then be read directly from the cross sections and input into the models. The profiles were also compared with ones constructed for some Martian lava flows.

Fink, J.↗

NASA NTRS1986

Correlations and contrasts in structural history and style between an Archaean greenstone belt and adjacent gneiss belt, NE Minnesota

An analysis of the deformation along the boundary between the Vermilion Granitic Complex (VGC) and the Vermilion district indicates that the two terranes have seen a similar deformation history since the earliest stages of folding in the area. Despite this common history, variations in structural style occur between the two terranes, such as the relative development of D sub 1 fabrics and D sub 2 shear zones, and these can be attributed to differences in the crustal levels of the two terranes during the deformation. Similarly, the local development of F sub 3 folds in the VGC, but not in the Vermilion district, is interpreted to be a result of later-D sub 2 pluton emplacement which was not significant at the level of exposure of ther Vermilion district.

Bauer, R. L.↗

NASA NTRS1985

Dynamical phenomena in the equatorial middle atmosphere during northern winter 1978-1979

Data from the Limb Infrared Monitor of the Stratosphere (LIMS) on the Nimbus-7 spacecraft were used to calculate the temperature and zonal wind structure of the equatorial stratosphere and lower mesosphere during the period October 25, 1978 to May 28, 1979. Interactions between the descending westerly shear zone of the semiannual oscillation and upward propagating Kelvin waves are described. Inertial instability may be influencing the zonal wind in midwinter.

Leovy, C. B.↗

NASA NTRS1985

Cenozoic extension and magmatism in Arizona

The Basin and Range Province of Arizona was the site of two episodes of Cenozoic extension that can be distinguished on the basis of timing, direction and style of extension, and associated magmatism. The first episode of extension occurred during Oligocene to mid-Miocene time and resulted in the formation of low-angle detachment faults, ductile shear zones (metamorphic core complexes), and regional domains of tilted fault blocks. Evidence for extreme middle Tertiary crustal extension in a NE to SW to SW to ENE to WSW direction has been recognized in various parts of the Basin and Range of Arizona, especially in the Lake Mead area and along the belf of metamorphic core complexes that crosses southern Arizona from Parker to Tucson. New geologic mapping and scrutiny of published geologic maps indicates that significant middle Tertiary extension is more widely distributed than previously thought. The state can be subdivided into regional tilt-block domains in which middle Tertiary rocks dip consistently in one direction. The dip direction in any tilt-block domain is generally toward the breakaway of a low-angle detachment fault that underlies the tilt-block domain; we interpret this an indicating that normal faults in the upper plate of a detechment fault are generally synthetic, rather than antithetic, with respect to the detachment fault.

Reynolds, S. J.↗

NASA NTRS1986

Planetary waves near the mesospheric easterly jet

Analysis of temperatures retrieved from satellite limb radiance measurements of the stratosphere and mesosphere during January-February 1979 reveals 3 prominent waves: wave number 3 with period 2.1 days, wave number 4 with period 1.8 days, and wave number 1 with period approximately 9 days. Each of these has maximum amplitude in the equatorward shear zone of the summer mesospheric easterly jet and propagates westward. Characteristics of the 1.8 day wave number 4 mode indicate that it arises from instability of the jet. The set of three waves may comprise an interacting triad.

Burks, D.↗

NASA NTRS1986

Merging of vortices in the atmosphere of Jupiter - An analysis of Voyager images

The present study of interactions between Jupiter spots, using the Voyager 2 cylindrical projection mosaics, notes that collisions between spots are irreversible, in contrast with solitary wave-type interactions. In 23 of 27 cases, interactions lead to a merging of the two original spots. Interactions of spots with filamentary regions usually lead to a disappearance of the spot; filamentary regions are noted to be the major source of spots. Stable spots do not generate other spots, instead destroying each other by merging. Most spots are anticyclonic, and lie in cyclonic shear zones.

Mac Low, M.-M.↗

NASA NTRS1986

Eddy processes in the general circulation of the Jovian atmospheres

Two fundamentally different views of the general circulation of Jovian atmospheres have emerged. According to one view, the observed jet streams at the cloud tops are controlled by the vorticity transfers of small scale eddies generated by planetary wave instabilities within a shallow atmospheric layer. According to the alternate point of view, the zonal jets are surface manifestations of deep interior convection organized into cylindrical motion with axes parallel to the planetary rotation axis. Both approaches may be considered in the context of the very different roles assumed by the potential vorticity. A possible reconciliation of the two kinds of dynamical systems is considered in which the interior motion is overlaid with a statically stable cappling layer driven by turbulent energy injection from below. A simple model for the eddy driving of quasi-geostrophic dynamics in the capping layer is presented which is consistent with the tentative evidence for up-gradient momentum flux on Jupiter and IRIS observations of thermal contrast correlations with cyclonic and anticyclonic shear zones. Certain synoptic-scale cloud features in Jupiter's atmosphere are interpreted as breaking waves, which may also influence the lateral mixing of tracers such as the ortho-para hydrogen ratio.

Leovy, Conway↗

NASA NTRS1987

Equatorial long-wave characteristics determined from satellite sea surface temperature and in situ data

SST maps and imagery derived from the NOAA 6 satellite AVHRR for June and July 1981 in the eastern tropical Pacific portray the wavelike structure of the cool water along the equator from 93 deg W to 125 deg W. Cusped waves of approximately 1000-km zonal wavelength and 25-day period propagated westward with a phase speed of 40 km/day. The observed meridional extent between the crest and trough of the waves is about 300 km. Details in the imagery show cooler water at the cusps advected north and then east with the north equatorial countercurrent (NECC), consistent with the suggestion of a series of anticyclonic eddies occupying the shear zone between the NECC and the westward flowing south equatorial current. Absolute SST estimates from the AVHRR data agree to within 0.6 C with shipboard data taken along 110 deg W between 5 deg N and 5 deg S. The wavelike structures in the SST maps are also in agreement at the surface with a vertical expendable bathythermograph temperature section made along the equator between 93 deg W and 125 deg W, which shows the phase of the waves tilting westward with increasing depth over the upper 75 m. Such a phase shift, if it extended 100-200 km meridionally in either direction from the equator, would be associated with an equatorward flux of heat. Similar phase shifts appear in temperature time series at depths of 20 and 50 m, from a mooring at 0-deg 33-min N, 110-deg 30-min W. Near-surface currents measured at this and a second mooring on the equator at 109-deg 40-min W indicate a regular pattern of northward advection when wave cusps pass them, followed by southwest flow during the passage of wave troughs, again consistent with an equatorward flux of heat, as well as with earlier theoretical and drift buoy findings.

Pullen, Patricia E.↗