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Sample records for clastic rocks

  1. Clastic rocks associated with the Midcontinent rift system in Iowa

    USGS Publications Warehouse

    Anderson, Raymond R.; McKay, Robert M.

    1997-01-01

    The Middle Proterozoic Midcontinent Rift System (MRS) of North America is a failed rift that formed in response to region-wide stresses about 1,100 Ma. In Iowa, the MRS is buried beneath 2,200?3,500 ft of Paleozoic and Mesozoic sedimentary rocks and Quaternary glaciogenic deposits. An extremely large volume of sediments was deposited within basins associated with the rift at several stages during its development. Although the uplift of a rift-axial horst resulted in the erosional removal of most of these clastic rocks from the central region of the MRS in Iowa, thick sequences are preserved in a series of horst-bounding basins. Recent studies incorporating petrographic analysis, geophysical modeling, and other analytical procedures have led to the establishment of a preliminary stratigraphy for these clastic rocks and interpretations of basin geometries. This information has allowed the refinement of existing theories and history of MRS formation in Iowa. Additionally, drill samples previously interpreted as indicating the existence of early Paleozoic basins overlying the Proterozoic MRS basins were re-examined. Samples previously interpreted as deep-lying Paleozoic rocks are now known to have caved from upper levels of the drillhole and were out of stratigraphic position. No deep Paleozoic basins exist in this area. These investigations led to the development of petrographic parameters useful in differentiating the Proterozoic MRS Red clastics from Paleozoic clastic rocks having similar lithologies.

  2. Clastic sedimentary rocks of the Michipicoten Volcanic-sedimentary belt, Wawa, Ontario

    NASA Technical Reports Server (NTRS)

    Ojakangas, R. W.

    1983-01-01

    The Wawa area, part of the Michipicoten greenstone belt, contains rock assemblages representative of volcanic sedimentary accumulations elsewhere on the shield. Three mafic to felsic metavolcanic sequences and cogenetic granitic rocks range in age from 2749 + or - 2Ma to 2696 + or - 2Ma. Metasedimentary rocks occur between the metavolcanic sequences. The total thickness of the supracrustal rocks may be 10,000 m. Most rocks have been metamorphosed under greenschist conditions. The belt has been studied earlier and is currently being remapped by Sage. The sedimentrologic work has been briefly summarized; two mainfacies associations of clastic sedimentary rocks are present - a Resedimented (Turbidite) Facies Association and a Nonmarine (Alluvial Fan Fluvial) Facies Association.

  3. Evaluation of weathering-resistance classes in clastic rocks on the example of Polish sandstones

    NASA Astrophysics Data System (ADS)

    Labus, Malgorzata

    2008-03-01

    The scope of the paper is an attempt at the identification of the weathering-resistance classes within clastic rocks by means of analysis of capillary pressure saturation curves. The porosimetric parameters corresponding to the cementing character and the grains’ mineralogical content are very important features of stone building materials, because of the weathering processes. The analysed rocks were Polish sandstones and muddy sandstones used for building purposes, collected from different geological units of Poland (i.e. Sudety Mts. Carpathian Mts. and Holy Cross Mts.) The results indicate the usefulness of sandstone materials for building purposes. They could also be used in conservation procedures and for the reconstruction of existing buildings and monuments. Basing on the parameterisation, with the van Genuchten function, of cumulative capillary pressure saturation curves, it was possible to distinguish four groups of the sampled rocks. The lithological features and weathering sustainability within the groups are quite uniform, what allow identifying the weathering resistance classes. Taking into account the complicated nature of all the factors influencing weathering processes, it is supposed that the presented parameterisation could be a useful tool for weathering-resistance classification of clastic rocks. The classification could be useful in building industry and in conservation of historical stone monuments.

  4. Sedimentology of clastic rocks returned from the moon by Apollo 15.

    NASA Technical Reports Server (NTRS)

    Lindsay, J. F.

    1972-01-01

    A petrographic study of eleven samples of clastic rock returned from the moon by Apollo 15 suggests that two lithologies are present. The distinction between the two lithologies is based on the glass content of the rock matrices and the morphology of the detrital particles. Group I rocks have abundant, glass-rich, porous matrices and glass particles with morphologies comparable to those of glass particles in the lunar soil. The group I rocks were probably formed by welding or sintering of surficial soil deposits by impact-generated base surges of limited extent. Group II rocks have an essentially mineralic matrix and have an abundance of rounded mineral grains. Sample 15455 is the only Apollo 15 sample assigned to this group. In its general textural features, sample 15455 is comparable with the group II rocks from the Fra Mauro Formation at the Apollo 14 site. Textural features such as shock modification and rounding of mineral grains suggest that this sample is the product of a large-scale impact-generated base surge which possibly resulted from the Imbrian event.

  5. A generalized Nadai failure criterion for both crystalline and clastic rocks based on true triaxial tests

    NASA Astrophysics Data System (ADS)

    Haimson, Bezalel; Chang, Chandong; Ma, Xiaodong

    2016-04-01

    The UW true triaxial testing system enables the application of independent compressive loads to cuboidal specimens (19×19×38 mm) along three principal directions. We used the apparatus to conduct extensive series of experiments in three crystalline rocks (Westerly granite, KTB amphibolite, and SAFOD granodiorite) and three clastic rocks of different porosities [TCDP siltstone (7%), Coconino sandstone (17%), and Bentheim sandstone (24%)]. For each rock, several magnitudes of σ3 were employed, between 0 MPa and 100-160 MPa, and for every σ3, σ2 was varied from test to test between σ2 = σ3 and σ2=(0.4 to 1.0) σ1.Testing consisted of keeping σ2and σ3constant, and raising σ1to failure (σ1,peak). The results, plotted as σ1,peakvs. σ2for each σ3 used, highlight the undeniable effect of σ2on the compressive failure of rocks. For each level of σ3, the lowest σ2 tested (σ2 = σ3) yielded the data point used for conventional-triaxial failure criterion. However, for the same σ3 and depending on σ2 magnitude, the maximum stress bringing about failure (σ1,peak) may be considerably higher, by as much as 50% in crystalline rocks, or 15% in clastic rocks, over that in a conventional triaxial test. An important consequence is that use of a Mohr-type criterion leads to overly conservative predictions of failure. The true triaxial test results demonstrate that a criterion in terms of all (three principal stresses is necessary to characterize failure. Thus, we propose a 'Generalized Nadai Criterion' (GNC) based on Nadai (1950), i.e. expressed in terms of the two stress invariants at failure (f), τoct,f = βσoct,f, where τoct,f = 1/3[(σ1,peak -σ2)2+(σ2 -σ3)2+(σ3 -σ1,peak)2]0.5 and σoct,f = (σ1,peak + σ2 + σ3)/3, and β is a function that varies from rock to rock. Moreover, the criterion depends also on the relative magnitude of σ2, represented by a parameter b [= (σ2 - σ3)/(σ1,peak - σ3)]. For each octahedral shear stress at failure (

  6. Standardizing texture and facies codes for a process-based classification of clastic sediment and rock

    USGS Publications Warehouse

    Farrell, K.M.; Harris, W.B.; Mallinson, D.J.; Culver, S.J.; Riggs, S.R.; Pierson, J.; ,; Lautier, J.C.

    2012-01-01

    Proposed here is a universally applicable, texturally based classification of clastic sediment that is independent from composition, cementation, and geologic environment, is closely allied to process sedimentology, and applies to all compartments in the source-to-sink system. The classification is contingent on defining the term "clastic" so that it is independent from composition or origin and includes any particles or grains that are subject to erosion, transportation, and deposition. Modifications to Folk's (1980) texturally based classification that include applying new assumptions and defining a broader array of textural fields are proposed to accommodate this. The revised ternary diagrams include additional textural fields that better define poorly sorted and coarse-grained deposits, so that all end members (gravel, sand, and mud size fractions) are included in textural codes. Revised textural fields, or classes, are based on a strict adherence to volumetric estimates of percentages of gravel, sand, and mud size grain populations, which by definition must sum to 100%. The new classification ensures that descriptors are applied consistently to all end members in the ternary diagram (gravel, sand, and mud) according to several rules, and that none of the end members are ignored. These modifications provide bases for standardizing vertical displays of texture in graphic logs, lithofacies codes, and their derivatives- hydrofacies. Hydrofacies codes are nondirectional permeability indicators that predict aquifer or reservoir potential. Folk's (1980) ternary diagram for fine-grained clastic sediments (sand, silt, and clay size fractions) is also revised to preserve consistency with the revised diagram for gravel, sand, and mud. Standardizing texture ensures that the principles of process sedimentology are consistently applied to compositionally variable rock sequences, such as mixed carbonate-siliciclastic ramp settings, and the extreme ends of depositional

  7. Sedimentology of clastic rocks from the Fra Mauro region of the moon.

    NASA Technical Reports Server (NTRS)

    Lindsay, J. F.

    1972-01-01

    A thin-section examination of sixteen clastic rock samples returned by the Apollo 14 mission from the Fra Mauro region of the moon suggests the presence of at least two distinctly different lithologies. Five of the samples (group I) are characterized by an abundant glassy matrix and glass particles and lesser amounts of plagioclase and pyroxene grains, and lithic clasts. The other eleven samples (group II) are relatively fine grained, very poorly sorted, and consist largely of pyroxene, plagioclase, and lithic clasts set in an abundant mineralic matrix. Group I and II lithologies were probably both deposited from impact generated base surges. The differences between them stem not as much from the basic sedimentary processes as from the differences in the magnitude of the events generating the base surges and the resultant difference in available detrital materials.

  8. Hydrogeologic assessment of shallow clastic and carbonate rock aquifers in Hendry and Collier counties, southwestern Florida

    USGS Publications Warehouse

    Brown, C. Erwin; Krulikas, R.K.; Brendle, D.L.

    1996-01-01

    Direct-current electrical resistivity data were collected from 109 vertical electrical sounding sites in Hendry and Collier Counties, southwestern Florida. Selected direct-current electrical resistivity surveys, together with available borehole geologic and geophysical data, were used to determine the approximate areal extent of the shallow clastic aquifers composed of thick sands and carbonate lithologies. Results indicated that a complex pattern of shallow sands, clays, and carbonate lithologies occur throughout the area. Buried channel sands were found as deep as 50 meters below land surface in some places. The channels contain unconsolidated fine- to medium-grained quartz sand interbedded with sandy limestone, shell fragments, and gray-green sandy clay. Both surface and borehole geophysical techniques with lithologic data were necessary to approximately locate and define layers that might behave as confining layers and to locate and define the extent of any buried sand aquifers. The borehole geophysical data were used to analyze the zones of higher resistivity. Direct-current electrical resistivity data indicated the approximate location of certain layer boundaries. The conjunctive use of natural gamma and short- and long-normal resistivity logs was helpful in determining lithologic effects. Geohydrologic sections were prepared to identify potential locations of buried channels and carbonates containing freshwater. Buried channel sands and carbonate rock sections were identified in the subsurface that potentially may contain freshwater supplies.

  9. Using the U-Pb system of calcretes to date the time of sedimentation of clastic sedimentary rocks

    NASA Astrophysics Data System (ADS)

    Wang, Z. S.; Rasbury, E. T.; Hanson, G. N.; Meyers, W. J.

    1998-08-01

    The time of sedimentation of rapidly deposited clastic sedimentary rocks in fluvial environments may be directly dated with an uncertainty of less than three million years using U-Pb dating of pure micritic calcite from calcretes developed in overbank deposits. This conclusion is based on results obtained for calcretes (soil calcite, caliche) formed in the late Triassic New Haven Arkose, Hartford Basin, Connecticut, USA. The paragenesis of calcrete samples from the New Haven Arkose was determined using plane-polarized light and cathodoluminesence petrography, uranium fission track analysis, as well as trace element and stable isotope geochemistry. These calcretes contain an abundance of paleosol microfabrics and diagenetic calcite. The first-generation micritic calcite and second-generation blocky calcite have characteristics consistent with soil calcite. The third generation blocky calcite is a later diagenetic calcite (post-soil calcite). The U-Pb data for pure micritic calcite (first generation) in a horizontal sheet calcrete in sedimentary rocks of Norian age gives a 238U/ 207Pb- 206Pb/ 207Pb isochron age of 211.9 ± 2.1 Ma (2-sigma, and used hereafter for all ages). This age and the stratigraphic position for this sample are in excellent agreement with the ages proposed by Gradstein et al. (1994) for the Norian/Rhaetian boundary of 209.6 ± 4.1 Ma and the Carnian/Norian boundary of 220.7 ± 4.4 Ma. The U-Pb data for two samples of first generation micrite in rhizoliths with about 15% insoluble residues give "ages" of 7 ± 66 Ma and 20 ± 36 Ma. These results suggest that relatively recent events disturbed the U-Pb system of these detrital rich samples, perhaps due to redistribution of U during weathering or during chemical dissolution for analysis. The U-Pb data for a sample of pure third generation blocky calcite cement in a rhizolith yields a 206Pb/ 238U- 207Pb/ 235U isochron age of 81 ± 11 Ma. This age suggests that this sample of third generation blocky

  10. A Multi-technique Approach for Provenance Studies of Mesozoic Clastic Rocks in the Barents Sea

    NASA Astrophysics Data System (ADS)

    Matthews, N. E.; Zimmermann, U.; Støle, L.; Ruud, C.; Mostafa, E.; Andò, S.; Borromeo, L.; Magnaghi, M.; Lapen, T. J.

    2015-12-01

    Sediments of Mesozoic age deposited in the Arctic Hammerfest and Tromsø basins (southern Barents Sea) are the focus of a comprehensive provenance study which forms part of ongoing work by the LoCrA consortium (Lower Cretaceous Basin Studies in the Arctic). Jurassic (Stø, Fuglen, Hekkingen) and Cretaceous (Knurr, Kolje, Kolmule) formations were sampled from seven wells. Analytical methods include petrography, whole-rock geochemistry, heavy mineral (HM) analysis and U-Pb on detrital zircons. HM concentration is <1%, with an ultrastable HM assemblage of zircon, rutile, tourmaline, spinel, apatite, garnet, chloritoid and common authigenic heavy minerals and opaques. Cretaceous sedimentary rocks show geochemical variations that reflect an unrecycled Upper Continental Crust signature, whereas Jurassic detritus tends to show more evidence of recycling with a relatively low input of mafic material. Kolmule Formation whole-rock geochemistry indicates sediment recycling from a major Sc-depleted but intermediate to mafic source and hence suggests input of rift detritus from the syn-depositional opening of the Atlantic Ocean. U-Pb ages for detrital zircons for Cretaceous sandstones show age groups of 200-500 Ma, 1200-1800 Ma, and 2100-2800 Ma, indicating potential source regions in the Urals/Novaya Zemlya, the Caledonides, Grenvillian/Sveconorwegian, and Palaeoproterozoic and Archean sources. Provenance data via geochemistry and HM analysis indicate different sources in the same formation basin-wide, with a significant change in provenance and sediment composition from Jurassic to Cretaceous and between the Knurr and Kolmule formations. These differences in composition need to be compared to detailed single grain studies and may only be explained in terms of basin dynamics, or even on a smaller scale, in terms of facies distributions. If so, this case study raises concerns about the use of single samples for provenance models on a larger scale.

  11. Using the U-Pb system of calcretes to date the time of sedimentation of clastic sedimentary rocks

    SciTech Connect

    Wang, Z.S.; Rasbury, E.T.; Hanson, G.N.; Meyers, W.J.

    1998-08-01

    The time of sedimentation of rapidly deposited clastic sedimentary rocks in fluvial environments may be directly dated with an uncertainty of less than three million years using U-Pb dating of pure micritic calcite from calcretes developed in overbank deposits. This conclusion is based on results obtained for calcretes (soil calcite, caliche) formed in the late Triassic New Haven Arkose, Hartford Basin, Connecticut, USA. The paragenesis of calcrete samples from the New Haven Arkose was determined using plane-polarized light and cathodoluminescence petrography, uranium fission track analysis, as well as trace element and stable isotope geochemistry. These calcretes contain an abundance of paleosol microfabrics and diagenetic calcite. The first-generation micritic calcite and second-generation blocky calcite have characteristics consistent with soil calcite. The third generation blocky calcite is a later diagenetic calcite (post-soil calcite). The U-Pb data for pure micritic calcite (first generation) in a horizontal sheet calcrete in sedimentary rocks of Norian age gives a {sup 238}U/{sup 207}Pb-{sup 206}Pb/{sub 207}Pb isochron age of 211.9 {+-} 2.1 Ma (2-sigma, and used hereafter for all ages). The U-Pb data for two samples of first generation micrite in rhizoliths with about 15% insoluble residues give ages of 7 {+-} 66 Ma and 20 {+-} 36 Ma. These results suggest that relatively recent events disturbed the U-Pb system of these detrital rich samples, perhaps due to redistribution of U during weathering or during chemical dissolution for analysis. The U-Pb data for a sample of pure third generation blocky calcite cement in a rhizolith yields a {sup 206}Pb/{sup 238}U-{sup 207}Pb/{sup 235}U isochron age of 81 {+-} 11 Ma. This age suggests that this sample of third generation blocky calcite precipitated during the late Cretaceous perhaps over an extended period.

  12. Fractured reservoirs in clastic rocks: Differences between a basement-cored structure and a detached fold belt

    SciTech Connect

    Engelder, T.; Gross, M.R.; Younes, A.

    1996-08-01

    The Elk Basin anticline, Wyoming-Montana, has an order of magnitude more structural relief than structures of the Appalachian Plateau, New York. Despite its structural relief the Elk Basin anticline shows very little macroscopic evidence for layer-parallel shortening vs. more than 10% for the subtle Appalachian Plateau folds. Elk Basin anticline is a passive drape fold extending over a tongue of basement punching up into the sedimentary cover. On the other extreme, the detached fold belt of the Appalachian Plateau remained in compression during most, if not all, of the Alleghanian layer-parallel shortening event. The joint pattern in Elk Basin is dominated by fold-parallel sets. The joint pattern in the Appalachian Plateau is dominated by fold-perpendicular sets. These two joint patterns are consistent with states of stress that suppress layer-parallel shortening in the former case and favor it in the latter case. Curvy cross joints are unambiguous records of the change in stress field orientation. Such structures in the clastic rocks of Elk Basin indicate a 10{degrees} to 15{degrees} clockwise reorientation of the stress field during later stages of fold development. The early to synfolding propagation of fold-parallel joints is indicated by their attitude normal to bedding on both limbs of the Elk Basin anticline. Fold-parallel joints are also rotated during strike-slip motion on later, vertical faults cutting subperpendicular to the anticlinal axis. Finally, the fracture spacing index for fold-parallel joints in various formations at Elk Basin is less than for cross fold joints of the Appalachian Plateau.

  13. U-Pb detrital zircon age patterns of Cenozoic clastic sedimentary rocks in Trinidad and its implications

    NASA Astrophysics Data System (ADS)

    Xie, Xiangyang; Mann, Paul

    2014-06-01

    The Cenozoic evolution of northern South America can be simplified as a diachronous, west-to-east change from north-facing passive margin, to active convergence and transcurrent plate margin. As the current eastern end of the Caribbean-South America plate boundary, the Trinidad area records the most recent tectonic regime transition. Documenting the provenance of Cenozoic clastic rocks in Trinidad provides insights into the spatial and temporal relationships between mountain range uplifting, sediment dispersal, and drainage system development along the eastern end of the Caribbean-South American plate boundary. Four Eocene to Pliocene age outcropping sandstone samples were collected from Trinidad and 545 detrital zircon grains were analyzed using the U-Pb LA-ICP-MS method. A total of 404 analyses with less than 10% discordance were used for the final interpretation. Results show that the age distribution of the Eocene to the Early Oligocene samples is very restricted and dominated by Precambrian age grains with age peaks at ~ 1400 Ma, ~ 1800 Ma, and ~ 2000 Ma, typically derived from the Guyana Shield. In contrast, the Late Oligocene and younger samples show much broader and mixed age distribution that includes Mesozoic, Paleozoic, and Precambrian peaks. This age shift was interpreted as arriving of the Great Caribbean Arc and oblique collision between the South America and Caribbean plates. Continuing collision uplifted the Andes belts to the west. The Eastern Cordillera of Colombia, the Merida Andes, and the northern Venezuela coastal ranges then became the second primary sources. Offshore sedimentation switched from the passive margin with multiple small drainage systems to the active convergent and transcurrent plate margin with a single large river-dominated delivery system.

  14. Evidence of Quaternary rock avalanches in the central Apennines: new data and interpretation of the huge clastic deposit of the L'Aquila basin (central Apennines, Italy)

    NASA Astrophysics Data System (ADS)

    Esposito, Carlo; Scarascia Mugnozza, Gabriele; Tallini, Marco; Della Seta, Marta

    2014-05-01

    Active extensional tectonics and widespread seismicity affect the axial zone of the central Apennines (Italy) and led to the formation of several plio-quaternary intermontane basins, whose morpho-evolution was controlled by the coupling of tectonic and climatic inputs. Common features of the Apennines intermontane basins as well as their general morpho-evolution are known. Nonetheless, the complex interaction among regional uplift, local fault displacements and morpho-climatic factors caused differences in the denudational processes of the single intermontane basins. Such a dynamic response left precious records in the landscape, which in some cases testify for the occurrence of huge, catastrophic rock slope failures. Several Quaternary rock avalanches have been identified in central Apennines, which are often associated with Deep Seated Gravitational Slope Deformation (DSGSD) and thus strictly related to the geological-structural setting as well as to the Quaternary morpho-structural evolution of the mountain chain. The L'Aquila basin is one of the intermontane tectonic depression aligned along the Middle Aterno River Valley and was the scene of strong historical earthquakes, among which the last destructive event occurred on April 6, 2009 (Mw 6.3). We present here the evidence that the huge clastic deposit on which the city of L'Aquila was built up is the body of a rock avalanche detached from the southern slope of the Gran Sasso Range. The clastic deposit elongates for 13 km to the SW, from the Assergi Plain to L'Aquila and is characterized by typical morphological features such as hummocky topography, compressional ridges and run-up on the opposite slope. Sedimentological characters of the deposit and grain size analyses on the matrix let us confirm the genetic interpretation, while borehole data and significant cross sections allowed us reconstructing the 3D shape and volume of the clastic body. Finally, morphometric analyses of the Gran Sasso Range southern

  15. Geochemistry of fine-grained clastic rocks in the Mesoproterozoic Kawabulake Group: implications for provenance and the tectonic model of the Eastern Tianshan, Xinjiang, NW China

    NASA Astrophysics Data System (ADS)

    Li, Deng-Feng; Chen, Hua-Yong; Zhang, Li; Fralick, Philip; Hollings, Pete; Mi, Mei; Lu, Wan-Jian; Han, Jin-Sheng; Wang, Cheng-Ming; Fang, Jing

    2017-01-01

    The Mesoproterozoic Kawabulake Group, which is unconformably overlain by the Lower Cambrian Huangshan Formation and conformably overlies the Mesoproterozoic Xingxingxia Group in the Eastern Tianshan area, NW China, is comprised mainly of siltstone, slate, sandstone and phyllite. New geochemical data for the clastic rocks from the Kawabulake Group were investigated to constrain the provenance and weathering history of the source rocks, in order to evaluate the tectonic evolution of the Eastern Tianshan area. Kawabulake Group rocks are compositionally similar to PAAS (average Post-Archean Australian Shale), indicating derivation from a felsic source that is characterized by depletion in some HFSEs such as Nb, Ta and Ti. The Chemical Index of Alteration (CIA) for the sandstone, siltstone and slate samples (CIA = 60 on average) suggests intensely weathered sources. Light REE-enrichment patterns ((La/Yb)CN = 4-20) coupled with negative Eu anomalies (Eu/Eu* between 0.44 and 0.89 with an average of 0.62) are similar to those of PAAS, consistent with cratonic sources. The major and trace element compositions imply a dominantly Precambrian felsic source region with a minor contribution from mafic materials. The Sr-Nd isotopic compositions and the ages of T DM2 ( 3.4, 2.5-1.8, 1.2 and 1.0 Ga) are consistent with the evolutionary history of Kuluketage in the northern Tarim, suggesting that the Tarim Craton was the main source area for the Kawabulake Group.

  16. Spatio-temporal autocorrelation of Neogene-Quaternary volcanic and clastic sedimentary rocks in SW Montana and SE Idaho: Relationship to Cenozoic tectonic and thermally induced extensional events

    NASA Astrophysics Data System (ADS)

    Davarpanah, A.; Babaie, H. A.; Dai, D.

    2013-12-01

    Two systems of full and half grabens have been forming since the mid-Tertiary through tectonic and thermally induced extensional events in SW Montana and neighboring SE Idaho. The earlier mid-Tertiary Basin and Range (BR) tectonic event formed the NW- and NE-striking mountains around the Snake River Plain (SRP) in Idaho and SW Montana, respectively. Since the mid-Tertiary, partially synchronous with the BR event, diachronous bulging and subsidence due to the thermally induced stress field of the Yellowstone hotspot (YHS) has produced the second system of variably-oriented grabens through faulting across the older BR fault blocks. The track of the migration of the YHS is defined by the presence of six prominent volcanic calderas along the SRP which become younger toward the present location of the YHS. Graben basins bounded by both the BR faults and thermally induced cross-faults (CF) systems are now filled with Tertiary-Quaternary clastic sedimentary and volcanic-volcaniclastic rocks. Neogene mafic and felsic lava which erupted along the SRP and clastic sedimentary units (Sixmile Creek Fm., Ts) deposited in both types of graben basins were classified based on their lithology and age, and mapped in ArcGIS 10 as polygon using a combination of MBMG and USGS databases and geological maps at scales of 1:250.000, 1:100,000, and 1:48,000. The spatio-temporal distributions of the lava polygons were then analyzed applying the Global and Local Moran`s I methods to detect any possible spatial or temporal autocorrelation relative to the track of the YHS. The results reveal the spatial autocorrelation of the lithology and age of the Neogene lavas, and suggest a spatio-temporal sequence of eruption of extrusive rocks between Miocene and late Pleistocene along the SRP. The sequence of eruptions, which progressively becomes younger toward the Yellowstone National Park, may track the migration of the YSH. The sub-parallelism of the trend of the SRP with the long axis of the

  17. Critical elements in sediment-hosted deposits (clastic-dominated Zn-Pb-Ag, Mississippi Valley-type Zn-Pb, sedimentary rock-hosted Stratiform Cu, and carbonate-hosted Polymetallic Deposits): A review: Chapter 12

    USGS Publications Warehouse

    Marsh, Erin; Hitzman, Murray W.; Leach, David L.

    2016-01-01

    Some sediment-hosted base metal deposits, specifically the clastic-dominated (CD) Zn-Pb deposits, carbonate-hosted Mississippi Valley-type (MVT) deposits, sedimentary-rock hosted stratiform copper deposits, and carbonate-hosted polymetallic (“Kipushi type”) deposits, are or have been important sources of critical elements including Co, Ga, Ge, and Re. The generally poor data concerning trace element concentrations in these types of sediment-hosted ores suggest that there may be economically important concentrations of critical elements yet to be recognized.

  18. Integrated Nd isotopic and U-Pb detrital zircon systematics of clastic sedimentary rocks from the Slave Province, Canada: evidence for extensive crustal reworking in the early- to mid-Archean

    NASA Astrophysics Data System (ADS)

    Yamashita, Katsuyuki; Creaser, Robert A.; Villeneuve, Mike E.

    2000-01-01

    A combined U-Pb geochronology and Nd isotopic analysis of clastic metasedimentary rocks from the Archean Slave Province, Northwest Territories, Canada is presented. A series of clastic sedimentary rocks with deposition age of ˜3.13 Ga to ˜2.58 Ga was collected from the west-central Slave Province. These samples include conglomerates as well as finer sedimentary rocks such as greywacke, arkose and quartzite. Although it is generally agreed that the Nd model age ( TDM) of clastic sedimentary rocks represents the average sedimentary provenance age, TDM of samples studied here is generally older than the average U-Pb age of detrital zircons extracted from the same sample. Rather, there seems to be a better ˜1:1 relationship between the TDM and U-Pb age of the oldest zircon from each sample. A simple model relationship between U-Pb geochronology and TDM suggests that such correlation is a result of Archean crustal evolution of the Slave Province being dominated by crustal reworking (i.e. intracrustal processes) rather than addition of juvenile materials from the mantle. One exception is the period between ˜3.1 and ˜3.2 Ga, during which period a significant portion of detrital zircons have U-Pb ages exceeding the TDM, indicating a large input of juvenile material and/or decreasing level of crustal reworking. An alternative explanation for the U-Pb vs. TDM trend may be a mixing of older mafic juvenile crust (containing no zircon) and younger felsic juvenile crust. However, the general lack of extensive pre-2.8 Ga mafic crust in the Slave Province makes this scenario unlikely. The results of this study cannot constrain the change in the volume of continental crust at any given period of time, since the addition of juvenile crust may always be counterbalanced by recycling of crustal material back into the mantle. However, a dominance of crustal reworking during the early- to mid-Archean strongly implies that a large part of ancient crust was lost during the younger

  19. Precambrian clastic sedimentation systems

    NASA Astrophysics Data System (ADS)

    Eriksson, P. G.; Condie, K. C.; Tirsgaard, H.; Mueller, W. U.; Altermann, W.; Miall, A. D.; Aspler, L. B.; Catuneanu, O.; Chiarenzelli, J. R.

    1998-09-01

    The unique and evolving nature of the Precambrian geological environment in many ways was responsible for significant differences between Precambrian clastic sedimentary deposits and their Phanerozoic-modern equivalents. Some form of plate tectonics, with rapid microplate collisions and concomitant volcanic activity, is inferred to have led to the formation of greenstone belts. Explosive volcanism promoted common gravity-flow deposits within terrestrial greenstone settings, with braided alluvial, wave/storm-related and tidal coastline sediments also being preserved. Late Archaean accretion of greenstone terranes led to emergence of proto-cratons, where cratonic and rift sedimentary assemblages developed, and these became widespread in the Proterozoic as cratonic plates stabilised. Carbonate deposition was restricted by the paucity of stable Archaean terranes. An Early Precambrian atmosphere characterised by greenhouse gases, including CO 2, in conjunction with a faster rotation of the Earth and reduced albedo, provide a solution to the faint young Sun paradox. As emergent continental crust developed, volcanic additions of CO 2 became balanced by withdrawal due to weathering and a developing Palaeoproterozoic microbial biomass. The reduction in CO 2, and the photosynthetic production of O 2, led to aerobic conditions probably being achieved by about 2 Ga. Oceanic growth was allied to atmospheric development, with approximately 90% of current ocean volume being reached by about 4 Ga. Warm Archaean and warm, moist Palaeoproterozoic palaeoclimates appear to have become more arid after about 2.3 Ga. The 2.4-2.3 Ga Huronian glaciation event was probably related to continental growth, supercontinent assembly and weathering-related CO 2 reduction. Despite many analogous features among both Precambrian and younger sedimentary deposits, there appear to be major differences as well. Two pertinent examples are rare unequivocal aeolian deposits prior to about 1.8 Ga and an

  20. Geochronological and geochemical constraints on the origin of clastic meta-sedimentary rocks associated with the Yuanjiacun BIF from the Lüliang Complex, North China

    NASA Astrophysics Data System (ADS)

    Wang, Changle; Zhang, Lianchang; Dai, Yanpei; Lan, Caiyun

    2015-01-01

    The Lüliang Complex is situated in the central part of the western margin of the Trans-North China Orogen (TNCO) in the North China Craton (NCC), and consists of metamorphic volcanic and sedimentary rocks and granitoid intrusions. The Yuanjiacun Formation metasediments occupy roughly the lowest part of the Lüliang Group and are mainly represented by well-bedded meta-pelites (chlorite schists and sericite-chlorite phyllites), banded iron formations (BIFs) and meta-arenites (sericite schists), which have undergone greenschist-facies metamorphism. The youngest group of detrital zircons from the meta-arenite samples constrains their maximum depositional age at ~ 2350 Ma. In combination with previous geochronological studies on meta-volcanic rocks in the overlying Jinzhouyu Formation, the depositional age of the Yuanjiacun Formation can be constrained between 2350 and 2215 Ma. The metasediments have suffered varying degrees of source weathering, measured using widely employed weathering indices (e.g., CIA, CIW, PIA and Th/U ratios). Source rocks of the low-Al meta-pelites have undergone severe chemical weathering, whereas those of the meta-arenites and high-Al meta-pelites have suffered relatively moderate chemical weathering. Significant secondary K addition is recognized in the A-CN-K diagram for most of the studied samples. Diagnostic geochemical features like the Al2O3/TiO2 values, trace element ratios (e.g., Th/Sc) and REE patterns, suggest that the meta-arenites and high-Al meta-pelites are predominantly derived from felsic igneous sources, whereas the low-Al meta-pelites are sourced mainly from mafic rocks. Coupled with Nd isotopic data, it is proposed that the meta-arenites and high-Al meta-pelites were sedimentary erosion products of the less differential felsic terrain (likely the old upper continental crust). The low-Al meta-pelites, however, have geochemical affinities with both pelite- and BIF-like components, suggesting that they were mixtures of these

  1. Physical and Chemical Effects of Two-Phase Brine/Supercritical-CO2 Fluid Flow on Clastic Rocks: Real-Time Monitoring and NMR Imaging of Flow-Through Core Experiments

    NASA Astrophysics Data System (ADS)

    Shaw, C. A.; Vogt, S.; Maneval, J. E.; Brox, T.; Skidmore, M. L.; Codd, S. L.; Seymour, J. D.

    2010-12-01

    Sandstone core samples were challenged with a supercritical CO2-saturated brine mixture in a laboratory flow-through core reactor system over a range of temperatures and brine strengths. Cores of quartz arenite from the Berea formation were selected to represent ideal ‘clean’ sandstone These laboratory experiments potentially provide an analog for the acidification of pore fluids near the brine/CO2 interface during CO2 flooding of depleted clastic hydrocarbon reservoirs for carbon sequestration. Flow in the reactor was perpendicular to bedding. Initial experiments were run at 50°C and 100°C with brine concentrations of 1g/L and 10g/L (TDS) to test effects of different temperatures and brine compositions. Real-time monitoring of fluid pH and conductivity provided a measure of reaction rates. Introduction of supercritical CO2 into the brine-saturated cores initiated a reduction in pH accompanied by an increase in conductivity. NMR images of fresh cores were compared with images of challenged cores using a protocol for pixel-by-pixel comparison to determine the effects on bulk pore volume and geometry. Two types of imaging experiments were conducted: multi-slice spin echo and 3-D spin echo images. Multi-slice experiments had a slice thickness of 1.5 mm and an in-plane resolution of 0.27 mm x 0.27 mm, and 3-D experiments had a resolution of 0.47 mm x 0.55 mm x 0.55mm. Imaging results reflected the observed changes in the physical and chemical structure post-challenge. Two-dimensional relaxation correlation experiments were also conducted to probe the pore sizes, connectivity and fluid saturation of the rock cores before and after challenging. Chemical analyses and microscopic examination of the challenged cores will provide a better understanding of alteration in the cores and the changes in the volume, geometry and connectivity of pore space.

  2. Distribution of Permo-Carboniferous clastics of Greater Arabian basin

    SciTech Connect

    Al-Laboun, A.A.

    1987-05-01

    Strikingly correlative sequences of sediments composed of sandstones, siltstones, shales, and thin argillaceous carbonate beds are present, practically everywhere, underlying the Late Permian carbonates in the Greater Arabian basin. The Greater Arabian basin as defined here occupies the broad Arabian Shelf that borders the Arabian shield. This basin is composed of several smaller basins. These clastics are exposed as thin bands and scattered small exposures in several localities around the margins of the basin. The Permo-Carboniferous clastics are represented by the Unayzah Formation of Arabia, the Doubayat Group of Syria, the Hazro Formation of southeast Turkey, the Ga'arah Formation of Iraq, the Faraghan Formation of southwest Iran, and the Haushi Group of Oman. A Late Carboniferous-Early Permian age is assigned to these clastics because they contain fossil plants and palynomorphs. These sediments represent time-transgressive fluctuating sea deposits following a phase of regional emergence, erosion, and structural disturbance which preceded the Permian transgression. The basal contact of these clastics is marked by a well-pronounced angular unconformity with various older units, ranging in age from early Carboniferous to late Precambrian. This regional unconformity is probably related to the Hercynian movements. The upper contact is conformable with the Permian carbonates. The porous sandstones of the Permo-Carboniferous sediments are important hydrocarbon exploration targets. These reservoir rocks sometimes overlie mature source rocks and are capped by shales, marls, and tight carbonates. Significant quantities of hydrocarbons are contained in these reservoirs in different parts of the Greater Arabian basin.

  3. Geologic assessment of undiscovered oil and gas resources in the Albian Clastic and Updip Albian Clastic Assessment Units, U.S. Gulf Coast Region

    USGS Publications Warehouse

    Merrill, Matthew D.

    2016-03-11

    U.S. Geological Survey National Oil and Gas Assessments (NOGA) of Albian aged clastic reservoirs in the U.S. Gulf Coast region indicate a relatively low prospectivity for undiscovered hydrocarbon resources due to high levels of past production and exploration. Evaluation of two assessment units (AUs), (1) the Albian Clastic AU 50490125, and (2) the Updip Albian Clastic AU 50490126, were based on a geologic model incorporating consideration of source rock, thermal maturity, migration, events timing, depositional environments, reservoir rock characteristics, and production analyses built on well and field-level production histories. The Albian Clastic AU is a mature conventional hydrocarbon prospect with undiscovered accumulations probably restricted to small faulted and salt-associated structural traps that could be revealed using high resolution subsurface imaging and from targeting structures at increased drilling depths that were unproductive at shallower intervals. Mean undiscovered accumulation volumes from the probabilistic assessment are 37 million barrels of oil (MMBO), 152 billion cubic feet of gas (BCFG), and 4 million barrels of natural gas liquids (MMBNGL). Limited exploration of the Updip Albian Clastic AU reflects a paucity of hydrocarbon discoveries updip of the periphery fault zones in the northern Gulf Coastal region. Restricted migration across fault zones is a major factor behind the small discovered fields and estimation of undiscovered resources in the AU. Mean undiscovered accumulation volumes from the probabilistic assessment are 1 MMBO and 5 BCFG for the Updip Albian Clastic AU.

  4. Rocks.

    ERIC Educational Resources Information Center

    Lee, Alice

    This science unit is designed for limited- and non-English speaking students in a Chinese bilingual education program. The unit covers rock material, classification, characteristics of types of rocks, and rock cycles. It is written in Chinese and simple English. At the end of the unit there is a list of main terms in both English and Chinese, and…

  5. Simulation model of clastic sedimentary processes

    SciTech Connect

    Tetzlaff, D.M.

    1987-01-01

    This dissertation describes SEDSIM, a computer model that simulates erosion, transport, and deposition of clastic sediments by free-surface flow in natural environments. SEDSIM is deterministic and is applicable to sedimentary processes in rivers, deltas, continental shelves, submarine canyons, and turbidite fans. The model is used to perform experiments in clastic sedimentation. Computer experimentation is limited by computing power available, but is free from scaling problems associated with laboratory experiments. SEDSIM responds to information provided to it at the outset of a simulation experiment, including topography, subsurface configuration, physical parameters of fluid and sediment, and characteristics of sediment sources. Extensive computer graphics are incorporated in SEDSIM. The user can display the three-dimensional geometry of simulated deposits in the form of successions of contour maps, perspective diagrams, vector plots of current velocities, and vertical sections of any azimuth orientation. The sections show both sediment age and composition. SEDSIM works realistically with processes involving channel shifting and topographic changes. Example applications include simulation of an ancient submarine canyon carved into a Cretaceous sequence in the National Petroleum Reserve in Alaska, known mainly from seismic sections and a sequence of Tertiary age in the Golden Meadow oil field of Louisiana, known principally from well logs.

  6. Organic geochemistry of Upper Carboniferous bituminous coals and clastic sediments from the Lublin Coal Basin

    NASA Astrophysics Data System (ADS)

    Gola, Marek R.; Karger, Michał; Gazda, Lucjan; Grafka, Oliwia

    2013-09-01

    Bituminous coals and clastic rocks from the Lublin Formation (Pennsylvanian, Westphalian B) were subjected to detailed biomarker and Rock-Eval analyses. The investigation of aliphatic and aromatic fractions and Rock-Eval Tmax suggests that the Carboniferous deposits attained relatively low levels of thermal maturity, at the end of the microbial processes/initial phase of the oil window. Somewhat higher values of maturity in the clastic sediments were caused by postdiagenetic biodegradation of organic matter. The dominance of the odd carbon-numbered n-alkanes in the range n-C25 to n-C31 , high concentrations of moretanes and a predominance of C 28 and C29 steranes are indicative of a terrigenous origin of the organic matter in the study material. This is supported by the presence of eudesmane, bisabolane, dihydro-ar-curcumene and cadalene, found mainly in the coal samples. In addition, tri- and tetracyclic diterpanes, e. g. 16β(H)-kaurane, 16β(H)-phyllocladane, 16α(H)-kaurane and norisopimarane, were identified, suggesting an admixture of conifer ancestors among the deposited higher plants. Parameters Pr/n-C17 and Rdit in the coal samples show deposition of organic matter from peat swamp environments, with the water levels varying from high (water-logged swamp) to very low (ephemeral swamp). Clastic deposits were accumulated in a flood plain environment with local small ponds/lakes. In pond/lake sediments, apart from the dominant terrigenous organic matter, research also revealed a certain quantity of algal matter, indicated, i.a., by the presence of tricyclic triterpanes C28 and C29 and elevated concentrations of steranes. The Paq parameter can prove to be a useful tool in the identification of organic matter, but the processes of organic matter biodegradation observed in clastic rocks most likely influence the value of the parameter, at the same time lowering the interpretation potential of these compounds. The value of Pr/Ph varies from 0.93 to 5.24 and from 3

  7. Clastic dikes of Heart Mountain fault breccia, northwestern Wyoming, and their significance

    USGS Publications Warehouse

    Pierce, W.G.

    1979-01-01

    Structural features in northwestern Wyoming indicate that the Heart Mountain fault movement was an extremely rapid, cataclysmic event that created a large volume of carbonate fault breccia derived entirely from the lower part of the upper plate. After fault movement had ceased, much of the carbonate fault breccia, here called calcibreccia, lay loose on the resulting surface of tectonic denudation. Before this unconsolidated calcibreccia could be removed by erosion, it was buried beneath a cover of Tertiary volcanic rocks: the Wapiti Formation, composed of volcanic breccia, poorly sorted volcanic breccia mudflows, and lava flows, and clearly shown in many places by inter lensing and intermixing of the calcibreccia with basal volcanic rocks. As the weight of volcanic overburden increased, the unstable water-saturated calcibreccia became mobile and semifluid and was injected upward as dikes into the overlying volcanic rocks and to a lesser extent into rocks of the upper plate. In some places the lowermost part of the volcanic overburden appears to have flowed with the calcibreccia to form dike like bodies of mixed volcanic rock and calcibreccia. One calcibreccia dike even contains carbonized wood, presumably incorporated into unconsolidated calcibreccia on the surface of tectonic denudation and covered by volcanic rocks before moving upward with the dike. Angular xenoliths of Precambrian rocks, enclosed in another calcibreccia dike and in an adjoining dikelike mass of volcanic rock as well, are believed to have been torn from the walls of a vent and incorporated into the basal part of the Wapiti Formation overlying the clastic carbonate rock on the fault surface. Subsequently, some of these xenoliths were incorporated into the calcibreccia during the process of dike intrusion. Throughout the Heart Mountain fault area, the basal part of the upper-plate blocks or masses are brecciated, irrespective of the size of the blocks, more intensely at the base and in places

  8. Pre-lithification tectonic foliation development in a clastic sedimentary sequence

    NASA Astrophysics Data System (ADS)

    Meere, Patrick; Mulchrone, Kieran; McCarthy, David; Timmermann, Martin; Dewey, John

    2016-04-01

    The current view regarding the timing of regionally developed penetrative tectonic fabrics in sedimentary rocks is that their development postdates lithification of those rocks. In this case fabric development is achieved by a number of deformation mechanisms including grain rigid body rotation, crystal-plastic deformation and pressure solution (wet diffusion). The latter is believed to be the primary mechanism responsible for shortening and the domainal structure of cleavage development commonly observed in low grade metamorphic rocks. In this study we combine field observations with strain analysis and modelling to fully characterise considerable (>50%) mid-Devonian Acadian crustal shortening in a Devonian clastic sedimentary sequence from south west Ireland. Despite these high levels of shortening and associated penetrative tectonic fabric there is a marked absence of the expected domainal cleavage structure and intra-clast deformation, which are expected with this level of deformation. In contrast to the expected deformation processes associated with conventional cleavage development, fabrics in these rocks are a product of translation, rigid body rotation and repacking of extra-formational clasts during deformation of an un-lithified clastic sedimentary sequence.

  9. Model for the incorporation of plant detritus within clastic accumulating interdistributary bays

    SciTech Connect

    Gastaldo, R.A.; McCarroll, S.M.; Douglass, D.P.

    1985-01-01

    Plant-bearing clastic lithologies interpreted as interdistributary bay deposits are reported from rocks Devonian to Holocene in age. Often, these strata preserve accumulations of discrete, laterally continuous leaf beds or coaly horizons. Investigations within two modern inter-distributary bays in the lower delta plain of the Mobile Delta, Alabama have provided insight into the phytotaphonomic processes responsible for the generation of carbonaceous lithologies, coaly horizons and laterally continuous leaf beds. Delvan and Chacalooche Bays lie adjacent to the Tensaw River distributary channel and differ in the mode of clastic and plant detrital accumulation. Delvan Bay, lying west of the distributary channel, is accumulating detritus solely by overbank deposition. Chacaloochee Bay, lying east of the channel, presently is accumulating detritus by active crevasse-splay activity. Plant detritus is accumulating as transported assemblages in both bays, but the mode of preservation differs. In Delvan Bay, the organic component is highly degraded and incorporated within the clastic component resulting in a carbonaceous silt. Little identifiable plant detritus can be recovered. On the other hand, the organic component in Chacaloochee Bay is accumulating in locally restricted allochthonous peat deposits up to 2 m in thickness, and discrete leaf beds generated by flooding events. In addition, autochthonous plant accumulations occur on subaerially and aerially exposed portions of the crevasse. The resultant distribution of plant remains is a complicated array of transported and non-transported organics.

  10. Provenance of the Walash-Naopurdan back-arc-arc clastic sequences in the Iraqi Zagros Suture Zone

    NASA Astrophysics Data System (ADS)

    Ali, Sarmad A.; Sleabi, Rajaa S.; Talabani, Mohammad J. A.; Jones, Brian G.

    2017-01-01

    Marine clastic rocks occurring in the Walash and Naopurdan Groups in the Hasanbag and Qalander areas, Kurdistan region, Iraqi Zagros Suture Zone, are lithic arenites with high proportions of volcanic rock fragments. Geochemical classification of the Eocene Walash and Oligocene Naopurdan clastic rocks indicates that they were mainly derived from associated sub-alkaline basalt and andesitic basalt in back-arc and island arc tectonic settings. Major and trace element geochemical data reveal that the Naopurdan samples are chemically less mature than the Walash samples and both were subjected to moderate weathering. The seaway in the southern Neotethys Ocean was shallow during both Eocene and Oligocene permitting mixing of sediment from the volcanic arcs with sediment derived from the Arabian continental margin. The Walash and Naopurdan clastic rocks enhance an earlier tectonic model of the Zagros Suture Zone with their deposition occurring during the Eocene Walash calc-alkaline back-arc magmatism and Early Oligocene Naopurdan island arc magmatism in the final stages of intra-oceanic subduction before the Miocene closure and obduction of the Neotethys basin.

  11. Belize model, a carbonate-clastic shelf buildup

    SciTech Connect

    Shepard, W.

    1987-05-01

    Belize, a small Central American country located on the Caribbean Sea south of the Yucatan Peninsula, offers an excellent modern analog of a mixed carbonate/clastic shelf buildup. Its 175-mi long reef tract, second longest in the world, restricts a shallow shelf depobasin into which terrigenous clastics source from the Maya Mountains to the west and carbonates dominate from the east. Mixed lithologies occur along strandlines, in submarine channels, and in lagoons and river-delta fronts, which are scattered throughout the depobasin. Energy sources from both land and sea influence sedimentation. Heavy summer rains flood the basin with arkosic and quartzose clastics, and periodic sea storms and hurricanes drive carbonate particles from the reef tract landward into the basin. Modern environments include the reef tract, carbonate tidal flats, shallow shelf patch reefs, lagoons, cayes, mainland coast deltas, estuaries, lagoons, and beach/bar barriers. Modern sediments include reef metazoans, algae, coralline algae, lime mud, quartz, and feldspathic sand and clay. The setting for the model has been influenced by Tertiary tectonics and Pleistocene sea level changes. Karstification occurred during the past 10,000 years, partly controlling topography and resulting Holocene sediment patterns. Facies patterns of the Belize Holocene are compared to the Jurassic of Montana. The Middle Jurassic Piper Formation exhibits a nearly 100-mi long carbonate barrier/buildup restricting a clastic-dominated shelf. Other ancient mixed carbonate/clastic terranes may fit this model as well.

  12. Rocks of the Columbia Hills

    USGS Publications Warehouse

    Squyres, S. W.; Arvidson, R. E.; Blaney, D.L.; Clark, B. C.; Crumpler, L.; Farrand, W. H.; Gorevan, S.; Herkenhoff, K. E.; Hurowitz, J.; Kusack, A.; McSween, H.Y.; Ming, D. W.; Morris, R.V.; Ruff, S.W.; Wang, A.; Yen, A.

    2006-01-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic or impact in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in Martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present. Copyright 2006 by the American Geophysical Union.

  13. Rocks of the Columbia Hills

    NASA Astrophysics Data System (ADS)

    Squyres, Steven W.; Arvidson, Raymond E.; Blaney, Diana L.; Clark, Benton C.; Crumpler, Larry; Farrand, William H.; Gorevan, Stephen; Herkenhoff, Kenneth E.; Hurowitz, Joel; Kusack, Alastair; McSween, Harry Y.; Ming, Douglas W.; Morris, Richard V.; Ruff, Steven W.; Wang, Alian; Yen, Albert

    2006-02-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic or impact in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in Martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present.

  14. Sequence stratigraphy simulations of carbonate, clastics, and mixed basin margins

    SciTech Connect

    Kendall, C.G.St.C.; Moore, P.; Birdwell, B.A.; Rouchie, L.; Cannon, R. ); Biswas, G. ); Bezdek, J. )

    1991-03-01

    Clastics, carbonates, and their mixtures have different depositional and post-depositional behavior that produces the different margin characteristics seen in seismic sequences. Carbonates undergo early cementation while maintaining higher angles of repose, while clays and sands accumulate at lower-angle slopes whose inclination is proportional to the grain size and post-depositional cohesive behavior. In higher energy regimes, waves or currents winnow less cohesive finer material that is transported downdip to from slope sediments rimming the basin. Simulations of mixed carbonate-clastic sediment accumulation, tectonism, and eustasy for settings in the Permian basin of west Texas and New Mexico show that sharp differentiation of clastics from carbonates is a product of higher angles of repose that carbonates maintain and the higher rates of clastic input at lowstands in sea level. In contrast, simulation of mixed grain-size margins like the Exmouth Plateau of Western Australia, the Baltimore Canyon, and the Gulf Coast Tertiary indicate that muds are winnowed preferentially from shelf-margin crests but accumulate on slopes, while sands accumulate on higher energy shelves. When they bypass at lowstands in sea level, they accumulate in the near slope basin but not on the slope. Simulation of pure carbonate systems like that of the Bahamian platform suggests that progradation is greatest in areas of low wave and current energy while backstepping and cliffed margins occur in high energy settings. The ability to accurately simulate mixed carbonate-clastic slopes is a key to development of exploration and production models of these systems.

  15. Elastic and Electrical Properties Evaluation of Low Resistivity Pays in Malay Basin Clastics Reservoirs

    NASA Astrophysics Data System (ADS)

    Almanna Lubis, Luluan; Ghosh, Deva P.; Hermana, Maman

    2016-07-01

    The elastic and electrical properties of low resistivity pays clastics reservoirs in Malay Basin are strongly dependent on the complex nature of the clay content, either dispersed or laminated/layered. Estimating the hydrocarbon pore volume from conventional electrical log, i.e. resistivity log, is quite a challenge. The low elastic impedance contrast also found as one of the challenge thus create a problem to map the distribution of the low resistivity reservoirs. In this paper, we evaluate the electrical properties and elastic rock properties to discriminate the pay from the adjacent cap rock or shale. Forward modeling of well log responses including electrical properties are applied to analyze the nature of the possible pays on laminated reservoir rocks. In the implementation of rock properties analysis, several conventional elastic properties are comparatively analyzed for the sensitivity and feasibility analysis on each elastic parameters. Finally, we discussed the advantages of each elastic parameters in detail. In addition, cross-plots of elastic and electrical properties attributes help us in the clear separation of anomalous zone and lithologic properties of sand and shale facies over conventional elastic parameter crossplots attributes. The possible relationship on electrical and elastic properties are discussed for further studies.

  16. Challenges modeling clastic eruptions: applications to the Lusi mud eruption, East Java, Indonesia.

    NASA Astrophysics Data System (ADS)

    Collignon, Marine; Schmid, Daniel; Mazzini, Adriano

    2016-04-01

    Clastic eruptions involve brecciation and transport of the hosting rocks by ascent fluids (gas and/or liquids), resulting in a mixture of rock clasts and fluids (i.e. mud breccia). This kind of eruptions is often associated with geological features such as mud volcanoes, hydrothermal vents or more generically with piercement structures. Over the past decades, several numerical models, often based on those used in volcanology, have been employed to better understand the behavior of such clastics systems. However, modeling multiphase flow is challenging, and therefore most of the models are considering only one phase flow. Many chemical, mechanical and physical aspects remain still poorly understood. In particular, the rheology of the fluid is one of the most important aspects, but also the most difficult to characterize. Experimental flow curves can be obtained on the finest fraction, but coarser particles (> 1mm) are usually neglected. While these experimental measurements usually work well on magma, they are much more difficult to perform when clay minerals are involved. As an initial step, we use analytical and simplified numerical models (flow in a pipe) to better understand the flow dynamics within a main conduit connected to an overpressured reservoir. The 2D numerical model solves the stokes equations, discretized on a finite element mesh. The solid phase is treated as rigid particles in suspension in the liquid. The gaseous phase (methane and carbon dioxide) is treated in an analytical manner using the equations of state of the H2O-CO2 and H2O-CH4 systems. Here, we present an overview of the state-of-the-art in modeling clastic eruptions as well as the limitations and challenges of such numerical models. We also discuss the challenges associated to the specific case of Lusi. In particular the difficulty to characterize the mud properties and the technical challenges associated with the acquisition of new data and development of more sophisticated models

  17. Mississippian clastic-to-carbonate transition in the northeastern Brooks Range, Alaska: Depositional cycles of the Endicott and Lisburne Groups

    SciTech Connect

    Lepain, D.L.; Crowden, R.K.; Watts, K.F. )

    1990-05-01

    The Ellesmerian sequence in northeastern Alaska consists of a thick succession of Mississippian to Lower Cretaceous platform carbonate and terrigenous clastic rocks. At the base of the Ellesmerian sequence, clastic rocks of the Endicott Group are the lower part of a major transgressive sequence that passes gradationally upward into carbonates of the Lisburne Group. In the Endicott Group, the basal Kekiktuk Conglomerate was deposited in fluvial and marginal marine environments. A broad suite of tidally influenced, shallow-marine environments are recorded in the overlying Kayak Shale. The transition into carbonate platform rocks of the Lisburne Group is recorded in a series of depositional cycles developed within the upper half of the Kayak Shale. In the lower beds of the transition, the depositional cycles are multiple upward-thickening and upward-coarsening successions composed of (1) organic-rich siltstone containing flaser-bedded and lenticular-bedded fine-grained sandstone, (2) fine-grained, ripple-laminated quartzarenite, and (3) an intensely bioturbated horizon of medium- to coarse-grained quartzarenite that contains scattered brachiopods, bryozoa, and crinoids. Each cycle is terminated by a sharp transgressive surface that consists of a thin shale drape. Near the top of the Kayak Shale, the coarse-grained horizons become increasingly replaced by wackestone, grainstone, and coralline boundstone. Despite the lithologic change, the vertical upward-thickening and upward-coarsening cycles continue in the basal limestone of the Lisburne Group. Repeated upward-shallowing episodes, followed by coastal onlap, are likely mechanisms for this cyclicity and suggests a genetic relation between both the clastic and carbonate depositional cycles.

  18. Clastic depositional styles and reservoir potential of Mediterranean basins

    SciTech Connect

    Bouma, A.H. )

    1990-05-01

    A variety of tectonic styles and activities throughout the late Mesozoic and younger epochs influenced sediment transport to the Mediterranean basins and, consequently, the approach needed to finding reservoir-type clastics. The style of the present-day basins varies from west to east, with large basinal depressions and continental rises in the western province, more elongate shapes in the central area, and numerous small basins and trenches in the eastern Mediterranean. In general terms, all these basins contain a similar fill: a deep-water sequence older than late Miocene, overlain by upper Miocene evaporites, and topped by Pliocene-Quaternary clastics. The exact type of fill depends on several factors, including proximity to the sediment source, climatic conditions, subsidence and tectonic activity, and tectono-eustatic or glacio-eustatic oscillations. Investigations on many of the clastic reservoirs in Mediterranean basins should emphasize submarine fans. The modern Mediterranean Sea contains several mid-sized fans (Rhone, Ebro, Valencia, and Nile fans) and many small ones (e.g., Crati Fan). There are several well-studied Tertiary subsurface and outcropping turbidite systems. The concept of deep-water marine sands, and many of the initial studies, began with some of the now classic outcrops in Italy, France, and Spain. A well-integrated study of both modern and ancient turbidite series is needed to construct basic exploration models for the Mediterranean region. 9 figs., 1 tab.

  19. Martian sediments and sedimentary rocks

    NASA Technical Reports Server (NTRS)

    Markun, C. D.

    1988-01-01

    Martian sediments and sedimentary rocks, clastic and nonclastic, should represent a high priority target in any future return-sample mission. The discovery of such materials and their subsequent analysis in terrestrial laboratories, would greatly increase the understanding of the Martian paleoclimate. The formation of Martian clastic sedimentary rocks, under either present, low-pressure, xeric conditions or a postulated, high-pressure, hydric environment, depends upon the existence of a supply of particles, various cementing agents and depositional basins. A very high resolution (mm-cm range) photographic reconnaissance of these areas would produce a quantum jump in the understanding of Martian geological history. Sampling would be confined to more horizontal (recent) surfaces. Exploration techniques are suggested for various hypothetical Martian sedimentary rocks.

  20. Mineralogy and geochemistry of pseudogley soils and recent alluvial clastic sediments in the Ngog-Lituba region, Southern Cameroon: An implication to their genesis

    NASA Astrophysics Data System (ADS)

    Ndjigui, Paul-Désiré; Ebah Abeng, Sandrine Appolonie; Ekomane, Emile; Nzeukou, Aubin Nzeugang; Ngo Mandeng, Francine Sidonie; Matoy Lindjeck, Marthe

    2015-08-01

    Mineralogical and geochemical investigations have been done on the hydromorphic clays (pseudogley soils and recent alluvial clastic sediments) in the Sanaga Maritime region (Southern Cameroon). Pseudogley soils are developed on gneisses from the Yaoundé Group. They have a dark brown to greyish brown color, with silty clay texture. Their mineral assemblage is made up of kaolinite, goethite, quartz, smectite, rutile, muscovite-illite and feldspars. The alluvial clastic sediments are characterized by variable colors (purple yellow, greenish, dark brown and purple brown) and sandy clay to clay texture. The mineral assemblage of alluvial clays is similar to that of pseudogley soils. SEM observations confirm the presence of kaolinite, smectite, quartz and muscovite-illite. Infrared data show that kaolinite is more orderly in pseudogley than in the alluvial clastic sediments. The Ngog-Lituba gneisses have moderate contents in SiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, K2O and several trace elements including REE. High element depletion is noticed in the pseudogley soils except Cr, V, Zr, Pb and REE. However, the alluvial clays are marked by a strong mobilization of LILE (Na, K, Ba, Rb and Sr) and REE, relative to the parent rock and pseudogley soils. The chondrite-normalized REE patterns are homogenous and parallel with Ce-anomalies. The (La/Yb)N shows that the REE fractionation increase from the parent rock to the alluvial clastic sediments. The mineralogical and geochemical features show that the clastic river sediments are derived from the erosion of the neighboring pseudogley materials before hydraulic sorting.

  1. Emplacement of the Jurassic Mirdita ophiolites (southern Albania): evidence from associated clastic and carbonate sediments

    NASA Astrophysics Data System (ADS)

    Robertson, Alastair H. F.; Ionescu, Corina; Hoeck, Volker; Koller, Friedrich; Onuzi, Kujtim; Bucur, Ioan I.; Ghega, Dashamir

    2012-09-01

    Sedimentology can shed light on the emplacement of oceanic lithosphere (i.e. ophiolites) onto continental crust and post-emplacement settings. An example chosen here is the well-exposed Jurassic Mirdita ophiolite in southern Albania. Successions studied in five different ophiolitic massifs (Voskopoja, Luniku, Shpati, Rehove and Morava) document variable depositional processes and palaeoenvironments in the light of evidence from comparable settings elsewhere (e.g. N Albania; N Greece). Ophiolitic extrusive rocks (pillow basalts and lava breccias) locally retain an intact cover of oceanic radiolarian chert (in the Shpati massif). Elsewhere, ophiolite-derived clastics typically overlie basaltic extrusives or ultramafic rocks directly. The oldest dated sediments are calpionellid- and ammonite-bearing pelagic carbonates of latest (?) Jurassic-Berrasian age. Similar calpionellid limestones elsewhere (N Albania; N Greece) post-date the regional ophiolite emplacement. At one locality in S Albania (Voskopoja), calpionellid limestones are gradationally underlain by thick ophiolite-derived breccias (containing both ultramafic and mafic clasts) that were derived by mass wasting of subaqueous fault scarps during or soon after the latest stages of ophiolite emplacement. An intercalation of serpentinite-rich debris flows at this locality is indicative of mobilisation of hydrated oceanic ultramafic rocks. Some of the ophiolite-derived conglomerates (e.g. Shpati massif) include well-rounded serpentinite and basalt clasts suggestive of a high-energy, shallow-water origin. The Berriasian pelagic limestones (at Voskopoja) experienced reworking and slumping probably related to shallowing and a switch to neritic deposition. Mixed ophiolite-derived clastic and neritic carbonate sediments accumulated later, during the Early Cretaceous (mainly Barremian-Aptian) in variable deltaic, lagoonal and shallow-marine settings. These sediments were influenced by local tectonics or eustatic sea

  2. The Rocks of the Columbia Hills

    NASA Technical Reports Server (NTRS)

    Squyres, Steven W.; Arvidson, Raymond E.; Blaney, Diana L.; Clark, Benton C.; Crumpler, Larry; Farrand, William H.; Gorevan, Stephen; Herkenhoff, Kenneth; Hurowitz, Joel; Kusack, Alastair; McSween, Harry Y.; Ming, Douglas W.; Morris, Richard V.; Ruff, Steven W.; Wang, Alian; Yen, Albert

    2006-01-01

    The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly-sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously-altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly-sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands, and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks, and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present.

  3. Clastic Pipes: Proxies of High Water Tables and Strong Ground Motion, Jurassic Carmel Formation, Southern Utah

    NASA Astrophysics Data System (ADS)

    Wheatley, David; Chan, Marjorie

    2015-04-01

    Multiple soft sediment deformation features from bed-scale to basin-scale are well preserved within the Jurassic Carmel Formation of Southern Utah. Field mapping reveals thousands of small-scale clastic injectite pipes (10 cm to 10 m diameter, up to 20 m tall) in extremely high densities (up to 500+ pipes per 0.075 square kilometers). The pipes weather out in positive relief from the surrounding host strata of massive sandstone (sabkha) and crossbedded sands with minor conglomerate and shale (fluvial) deposits. The host rock shows both brittle and ductile deformation. Reverse, normal, and antithetical faulting is common with increased frequency, including ring faults, surrounding the pipes. The pipes formed from liquefaction and subsequent fluidization induced by strong ground motion. Down-dropped, graben blocks and ring faults surrounding pipes indicate initial sediment volume increase during pipe emplacement followed by sediment volume decrease during dewatering. Complex crosscutting relationships indicate several injection events where some pipe events reached the surface as sand blows. Multiple ash layers provide excellent stratigraphic and temporal constraints for the pipe system with the host strata deposited between 166 and 164 Ma. Common volcanic fragments and rounded volcanic cobbles occur within sandstone and conglomerate beds, and pipes. Isolated volcanic clasts in massive sandstone indicate explosive volcanic events that could have been the exogenic trigger for earthquakes. The distribution of pipes are roughly parallel to the Middle Jurassic paleoshoreline located in marginal environments between the shallow epicontinental Sundance Sea and continental dryland. At the vertical stratigraphic facies change from dominantly fluvial sediments to dominantly massive sabkha sediments, there is a 1-2 m-thick floodplain mudstone that was a likely seal for underlying, overpressurized sediments. The combination of loose porous sediment at a critical depth of water

  4. Paleomagnetism of clastic dikes along the Front Range, Colorado

    NASA Astrophysics Data System (ADS)

    Dulin, S. A.; Elmore, R. D.

    2011-12-01

    Numerous clastic dikes occur within the Proterozoic basement along nearly 75km of the Front Range of Colorado. These dikes are composed predominately of well-rounded, non-metamorphosed quartz and are red in color due to the abundance of authigenic hematite. The Cambrian Sawatch sandstone is assumed by most studies to be the source of dike sediments due to its similar composition. Despite over a century of study, the origins, age, and emplacement mechanisms of these dikes remain enigmatic. A preliminary paleomagnetic study of the clastic dikes using standard demagnetization techniques indicates the presence of a complex multicomponent magnetization with at least three components. An easterly and moderately steep component residing in hematite was resolved from several dikes and corresponds to an early Cambrian pole position when compared to the apparent polar wander path of North America. An east-southeasterly and shallow magnetization, also residing in hematite, yields a pole of early Paleozoic age. The third component is northwesterly and steep down and is Mesozoic or Cenozoic in age. These results are similar to a previous paleomagnetic study (Kost, MS thesis, Univ. Colorado) in 1984 of different dikes which found poorly defined early and late Paleozoic, as well as Mesozoic-Cenozoic components. Many researchers suggest emplacement occurred during faulting that was associated with either the Ancestral Rockies uplift of the late Paleozoic or the Laramide orogeny of the late Mesozoic/early Cenozoic. The presence of magnetizations of Cambrian age, with subsequent younger remagnetizations, indicates that the emplacement of many of the dikes preceded both of these tectonic events.

  5. Late Mississippian (Chesterian) carbonate to carbonate-clastic cycles in the eastern Illinois Basin

    SciTech Connect

    Smith, L.B.; Read, J.F. )

    1994-03-01

    Late Mississippian (Chesterian) rocks of the eastern Illinois Basin in Kentucky and Indiana show depositional cycles (3--20 meters thick) composed of a range of facies deposited during the transition from carbonate-dominated deposition of the Middle Mississippian to the predominantly siliciclastic regime of the Pennsylvanian. Within the basal Ste. Genevieve Formation (30--70 meters thick) there are five predominantly carbonate cycles. Cycle bases vary from thin calcareous sandstone near the northern clastic source to ooid-quartz dolomitic pelletal grainstone and mudstone further south. Massive cross-bedded and channeled ooid-skeletal grainstones represent the cycle tops and are commonly capped by caliche and subaerial breccia, particularly where there was no subsequent siliciclastic deposition. The cycles are interpreted to be driven by fourth-order (400 k.y.) glacio-eustatic sea-level fluctuations based on coincidence of the calculated cycle period with the long-term eccentricity signal, the Late Mississippian onset of Gondwana glaciation and cycle correlation over more than 100 kilometers. The breccia and caliche formed during lowstands, the siliciclastics, eolianites and dolomitic pelletal grainstones are transgressive facies and the ooid-skeletal grainstones represent sea-level highstands.

  6. Progressive chemical modification of clastic sediments with burial

    NASA Astrophysics Data System (ADS)

    Curtis, C. D.

    1987-03-01

    The porosity of clastic sediments at deposition varies very approximately between about 45% (sands) and 85% (muds). With burial, consolidation takes place as pore water is progressively eliminated. It would be misleading, however, to attribute alterations in sediment bulk properties to physical processes alone. Very significant mineralogical changes occur and these start soon after burial, especially in mudrocks. Striking heterogeneities such as thin, laterally continuous cemented horizons or discrete concretions are commonly introduced. These shallow burial processes are predominently the result of microbial activity. Thermodynamically unstable mixtures of organic matter and various oxidants [dissolved oxygen, sulphate, nitrate, particulate Fe(III) and Mn(IV)] provide both substrate and energy source for a variety of different microbial ecosystems. Mineralogical consequences include both leaching and the precipitation of carbonate, sulphide, phosphate and silica cements. The type and extent of mineral modification depends strongly on depositional environment variables such as rate of sedimentation and water composition. At greater depths, large scale modification of detrital clay minerals (particularly the smectite-I/S-illite transformation) takes place. Recent work of various kinds, however, has demonstrated that these changes may not be solid state transformations: clay mineral dissolution, transport and precipitation occur much more widely than was formerly supposed. In sandstones, authigenic precipitation of clay minerals from pore solution is much more obviouis. Systematic patterns of precipitation, alteration and replacement have been documented in many sedimentary basins. Porosity and permeability are reduced by cementation and, sometimes, enhanced by mineral dissolution. Whereas the general nature of these chemical reactions is fairly well understood, it is not yet possible to predict with certainty the scale or distribution of mineralogical consequences

  7. Back to sender: tectonic accretion and recycling of Baltica-derived Devonian clastic sediments in the Rheno-Hercynian Variscides

    NASA Astrophysics Data System (ADS)

    Franke, Wolfgang; Dulce, Joachim-Christian

    2017-01-01

    Sedimentary petrography and zircon ICP-MS laser ablation ages from synorogenic clastic sediments in the Rheno-Hercynian Belt of Germany (Rheinisches Schiefergebirge, Harz) reveal basal tectonic accretion followed by exhumation and recycling of Baltica-derived Devonian shelf sediments. The recycled sediment volume demands a substantial palinspastic addition to the passive, northern margin of the Rheno-Hercynian basin. Detrital zircon ages from the Late Carboniferous foreland basin and their possible source rocks in the South Portuguese Zone permit the same interpretation. This suggests that synorogenic sedimentation in Portugal is related, like in Germany, to the closure of the Devonian-Carboniferous Rheno-Hercynian basin and not to the closure of the Ordovician-Silurian Rheic Ocean.

  8. Predicting carbonate mineral precipitation/dissolution events during progressive diagenesis of clastic rocks

    SciTech Connect

    Surdam, R.C.; MacGowan, D.B.; Dunn, T.L. ); Moraes, M. )

    1991-03-01

    There is an observable, regular progression of early and late carbonate cements that is separated by carbonate mineral dissolution in many sandstones during progressive burial and diagenesis. The distribution of early cements is a function of incipient hydration of framework grains, sulfate reduction, and bacterial methanogenesis. These early cements typically precipitate from the sediment water interace to burial depths corresponding to about 80C. The distribution of late carbonate cements is a function of the relationship of organic acid anions, aluminosilicate reactions and CO{sub 2} in formation waters. Elevated PCO{sub 2} in a fluid where the pH is buffered by organic acid anions or aluminosilicates results in precipitation of a late carbonate cement (typically ferroan); these late carbonate cements generally form over the temperature interval of 100-130C. The late and early carbonate cement events are separated in time by a period of carbonate mineral dissolution or nonprecipitation. This dissolution is related to the increase in concentration of carboxylic acid anions resulting from the thermocatalytic cracking of oxygen-bearing functional groups from kerogen and/or redox reactions involving kerogen. Examples of the importance of early carbonate cementation/decementation to hydrocarbon reservoirs include the Campos basin of Brazil and the U.S. Gulf Coast. An example of late carbonate cementation/decementation includes the Norphlet Formation. This observed sequence of cementation and decementation can be modeled, and the modeling results can be used to predict enhanced porosity in the subsurface.

  9. Gamma ray spectrometry logs as a hydrocarbon indicator for clastic reservoir rocks in Egypt.

    PubMed

    Al-Alfy, I M; Nabih, M A; Eysa, E A

    2013-03-01

    Petroleum oil is an important source for the energy in the world. The Gulf of Suez, Nile Delta and South Valley are important regions for studying hydrocarbon potential in Egypt. A thorium normalization technique was applied on the sandstone reservoirs in the three regions to determine the hydrocarbon potentialities zones using the three spectrometric radioactive gamma ray-logs (eU, eTh and K% logs). The conventional well logs (gamma-ray, deep resistivity, shallow resistivity, neutron, density and sonic logs) are analyzed to determine the net pay zones in these wells. Indices derived from thorium normalized spectral logs indicate the hydrocarbon zones in petroleum reservoirs. The results of this technique in the three regions (Gulf of Suez, Nile Delta and South Valley) are in agreement with the results of the conventional well log analyses by ratios of 82%, 78% and 71% respectively.

  10. Cementitious Mixtures for Sealing Evaporite and Clastic Rocks in a Radioactive-Waste Repository.

    DTIC Science & Technology

    1985-09-01

    on other materials (Struble, Skalny, and Mindess 1980; Barnes, Diamond, and Dolch 1978). Images of chloride distribution show concentrations of...Waste Management, US Department of Energy, Washington, DC. Struble, L., Skalny, L., and Mindess , S. 1980. Cement and Concrete Research, Vol 10, pp

  11. Calcareous nannofossils and clastic sediments at the Cretaceous-Tertiary boundary, northeastern Mexico

    NASA Astrophysics Data System (ADS)

    Pospichal, James J.

    1996-03-01

    A quantitative analysis of calcareous nannofossil assemblages on the Cretaceous-Tertiary (K-T) boundary of the Mimbral and Mulato outcrops of northeast Mexico indicates that the sections are biostratigraphically complete across the boundary and that there is a prominent spherule-bearing clastic unit located precisely at the K-T boundary. The sections consist of uppermost Maastrichtian (Micula prinsii Zone) marly limestones of the Mendez Formation and marlstones of the lower Paleocene (Zone NP1) Velasco Formation separated by a distinct, 1 3-m-thick sandstone unit that has a basal spherule-bearing layer. The origin of this clastic unit and the time of deposition relative to the K-T mass extinctions have been the subjects of much controversy. Some workers attribute this unit to rapid tsunami-induced deposition triggered by the nearby Chicxulub impact, and others consider it a turbidite deposited at some time prior to the K-T mass extinctions. Cretaceous nannofossils abruptly decrease in abundance at the base of the spherule bed and only rare to few reworked specimens are present in the clastic unit and in the basal Velasco Formation. Survivors and Tertiary species are common above the clastic unit. Cretaceous nannoplankton show no evidence of recovery after deposition of the clastic unit, which indicates that extinctions probably occurred correlative with the deposition of the clastic unit and in association with the Chicxulub impact.

  12. A conceptual review of regional-scale controls on the composition of clastic sediment and the co-evolution of continental blocks and their sedimentary cover.

    PubMed

    Cox, R; Lowe, D R

    1995-01-02

    Both sediment recycling and first-cycle input influence the composition of clastic material in sedimentary systems. This paper examines conceptually the roles played by these processes in governing the composition of clastic sediment on a regional scale by outlining the expected effects on sediment composition of protracted sediment recycling and of continuous first-cycle input on a maturing continental block. Generally speaking, long-term recycling tends to enrich sediments in the most chemically and mechanically stable components: quartz in the sand and silt size fractions, and illite among the clay minerals. Sandstones trend towards pure quartz arenites, and mudrocks become more potassic and aluminous. The average grain size of clastic sediment decreases by a combination of progressive attrition of sand grains and ongoing breakdown of primary silicate minerals to finer-grained clay minerals and oxides. Sandstones derived by continuous first-cycle input from an evolving continental crustal source also become increasingly rich in quartz, but in addition become more feldspathic as the proportion of granitic material in the upper continental crust increases during crustal stabilization. Associated mudrocks also become richer in potassium and aluminum, but will have higher K2O/Al2O3 ratios than recycled muds. The average grain size of the sediment may increase with time as the proportion of sand-prone granitic source rocks increases at the expense of more mud-prone volcanic sources. In general, except in instances where chemical weathering is extreme, first-cycle sediments lack the compositional maturity of recycled detritus, and are characterized by the presence of a variety of primary silicate minerals. Sedimentary systems are not usually completely dominated by either recycling or first-cycle detritus. Generally, however, sedimentary systems associated with the earliest phases of formation and accretion of continental crust are characterized by first-cycle input

  13. Simulating transport and deposition of clastic sediments in an elongate basin using the SIMSAFADIM-CLASTIC program: The Camarasa artificial lake case study (NE Spain)

    NASA Astrophysics Data System (ADS)

    Gratacós, O.; Bitzer, K.; Casamor, J. L.; Cabrera, L.; Calafat, A.; Canals, M.; Roca, E.

    2009-12-01

    Predicting facies distribution and the stratigraphic architecture of sedimentary basins by process-oriented numerical models is nowadays an essential tool in geologic studies. They constitute a new approach to predict the geologic heterogeneity and the spatial distribution of the diverse facies generated in a depositional system jointly with the distribution of the physical, chemical, and petrophysical characteristics of the sedimentary deposits in a quantitative way. SIMSAFADIM-CLASTIC is a 3D process-based, forward numerical model for the simulation of clastic sediment transport and sedimentation in aquatic systems. It simulates the physical process of clastic transport using the advective, diffusive, and dispersive terms of the transport equation and clastic sediment deposition as a result of a variety of processes. The capabilities of SIMSAFADIM-CLASTIC have been confirmed through the application of the program to a large deep elongated artificial lake, the Camarasa reservoir in the Noguera Pallaresa River, NE of Spain. Simulation results yield sedimentation rates ranging from 0.04 to 0.09 cm·yr - 1 close to the dam, and from 1.73 to 1.63 cm·yr - 1 in the upper reservoir section. The sample experiment results match well with the observed transport pattern linked to the flow system in Camarasa's reservoir near-bottom water layer, which transports more than 50% of the sediment that is supplied to the reservoir. Opening and closure of turbine gates and the basin geometry are the main controlling factors on the fluid flow and depositional pattern in the reservoir, with a more diversified pattern obtained when an open boundary is defined. However, the resulting model also shows some limitations of the program as it does consider a stratified water column that is consistently observed in the reservoir. Refined modeling exercises of the type described in this paper are of potential application to predict and quantify sedimentation patterns allowing the

  14. Influence of Clastic Dikes on Vertical Migration of Contaminants at the Hanford Site

    SciTech Connect

    Murray, Christopher J.; Ward, Andy L.; Wilson, John

    2007-11-20

    Clastic dikes are subvertical sedimentary features that cut through horizontally layered sediments, and they are common at the Hanford Site. Because of their cross-cutting relationship with the surrounding matrix, they have been proposed as potential fast paths from former contaminant discharge sites at the surface to the water table. However, little was known of the detailed hydrogeologic properties of the dikes and detailed modeling of flow and transport through the dikes had not been performed. We excavated a 2 m wide clastic dike at the Hanford Site and characterized it using an air minipermeameter, infrared imagery, and grain size analyses. Field injection experiments were also used to characterize the system. The resulting data were used to prepare a detailed numerical model of the clastic dike and surrounding matrix for a portion of the excavation. Unsaturated flow and transport through the system were modeled for several recharge rates. The highly heterogeneous nature of the system led to complex behavior, with the relative flux rates in the matrix and clastic dike being highly dependent on the recharge rates that were imposed on the system. The study suggests that the potential role of clastic dikes in vertical transport at the Hanford Site would depend on the leakage rate, and that areas of contaminant deposition formed at high flow rates might become isolated at low flow rates, and vice-versa. The results may also help explain the occurrence of complex breakthrough patterns of contaminants at the water table.

  15. Granitic rocks and metasediments in Archean crust, Rainy Lake area, Ontario: ND isotope evidence for mantle-like SM/ND sources

    NASA Technical Reports Server (NTRS)

    Shirey, S. B.; Hanson, G. N.

    1983-01-01

    Granitoids, felsic volcanic rocks and clastic metasediments are typical rocks in Archean granite-greenstone belts that could have formed from preexisting continentasl crust. The petrogenesis of such rocks is assessed to determine the relative roles of new crust formation or old crust formation or old crust recycling in the formation of granite-greenstone belts.

  16. A mixed clastic-carbonate lake margin succession from Triassic of East Greenland

    NASA Astrophysics Data System (ADS)

    Andrews, Steven

    2016-04-01

    Lake margin deposits are being increasingly studied, but this is often focussed on either clastic or carbonate/microbial dominated end members. This study examines the interaction of clastic and carbonate system from a dynamic lake margin. The Late Triassic Edderfugledal Member outcrops between 71° and 72° 40' N in East Greenland. Throughout the Late Triassic, lacustrine conditions predominated and deposition occurred in the largely closed, underfilled Jameson Land Basin which lay at approximately 30° to 40° north in Northern Pangea. Regular fluctuations in lake level, interpreted as a response to cyclic, orbitally forced climatic variance, resulted in a highly mobile lake shore zone. The response and interaction of both clastic and carbonate components of the shore zone environment to these fluctuations in lake level are documented in this study. The studied, ≈ 10 m thick, section which has been traced for over 4 km, lies within the transition between the carbonate dominated Sporfjeld Beds and the overlying Pingel Dal Beds which contain an increased clastic content. During the deposition of the Edderfugledal Member, arid conditions prevailed leading to more ephemeral lacustrine developments and low sediment input. Extensive post depositional disruption occurred with there being evidence for desiccation, pedogenic processes and evaporite precipitation. These effects increase towards the lake margins where exposure was most regular and most prolonged. Up section, increasingly humid conditions led to the formation of longer lived lacustrine developments and increased clastic sediment input. During the transgressive phases of individual climatically driven cycles, sediment input was pushed back to the lake margin allowing extensive microbialite development. Ooidal shoals developed in shallow water beyond the extend of clastic input. The lakeward migration of the ooidal shoals and the progradation of clastic systems eventually stifle the microbialites prior to

  17. Clastic-hosted stratiform, vein/breccia and disseminated Zn-Pb-Ag deposits of the northwestern Brooks Range, AK: Are they different expressions of dewatering of the same source basin

    SciTech Connect

    Schmidt, J.M. ); Werdon, M.B. . Dept. of Geology)

    1993-04-01

    Sphalerite and galena, with significant silver occur in 3 distinct types of mineralization hosted in Upper Devonian and Carboniferous clastic rocks of the northwestern Brooks Range. The best known are Zn-Pb-Ag massive sulfide deposits with variable pyrite, barite, and hydrothermal silifica hosted in Mississippian (to Pennsylvanian ) black siliceous shale and chert, and similar to shale-hosted Pb-Zn massive sulfide deposits worldwide. Zn-Pb-Ag breccias and veins are hosted in Upper Devonian to Lower Mississippian fine-grained quartzites and siltstone which stratigraphically underlie the massive sulfide-hosting units. The breccia-vein and disseminated occurrences are co-extensive with the rocks that host massive sulfide deposits, and with the western part of the Endicott Group clastic basin. Pb isotopic ratios of galena from all the deposits are remarkably uniform, and suggest a single Pb source. The authors genetic model suggests that all types are the result of dewatering of a single clastic source basin. Different mineralization styles are probably due to variable depths of emplacement (at or below the seafloor), thermal variations related to extensional thinning of the crust, and hydrologic flow out of the basin controlled by extensional thinning of the crust, and hydrologic flow out of the basin controlled by extensional faulting and permeability variations in local stratigraphy. The most likely sources for Zn and Pb are clay minerals within the lowermost (Hunt Fork Shale) portions of the western Endicott Group.

  18. 70193-Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zonde at Hanford

    SciTech Connect

    Christopher J Murray; Anderson L. Ward; John L. Wilson

    2004-04-07

    The purpose of this study was to examine the hypothesis that clastic dikes could form a preferential flow path through the vadose zone to the water table at the Hanford Site. Clastic dikes are subvertical structures that form within sedimentary sequences after deposition and cut across the original sedimentary layers. They are common throughout the Hanford Site, often occurring in organized polygonal networks. In the initial phase of the project, we analyzed the large-scale geometry of the clastic dikes and developed an algorithm for simulating their spatial distribution. This result will be useful in providing maps of the potential distribution of clastic dikes in areas where they are not exposed at the surface (e.g., where covered by windblown sand or construction of facilities like tank farms at the surface). In addition to the study of the large-scale distribution of the dikes, a major focus of the project was on field, laboratory, and modeling studies of the hydrogeological properties of the clastic dikes and the effect that they have on transport of water through the vadose zone. These studies were performed at two field locations at the Hanford Site. We performed an extensive series of field and laboratory measurements of a large number of samples from the clastic dikes, linked with infrared (IR) and visual imagery of the clastic dikes and surrounding matrix. We developed a series of correlations from the sample data that allowed us to estimate the unsaturated hydraulic conductivity of the dike and matrix at an extremely high resolution (approximately 1 mm). The resulting grids, each of which measured several meters on a side and included nearly four million grid nodes, were used to study the distribution of moisture between the clastic dike and surrounding matrix, as well as the relative velocities that moisture would have through the clastic dike and matrix for a number of different recharge scenarios. Results show the development of complex flow networks

  19. Clastic metasediments of the Early Proterozoic Broken Hill Group, New South Wales, Australia: Geochemistry, provenance, and metallogenic significance

    USGS Publications Warehouse

    Slack, J.F.; Stevens, B.P.J.

    1994-01-01

    Whole-rock analyses of samples of pelite, psammite, and psammopelite from the Early Proterozoic Broken Hill Group (Willyama Supergroup) in the Broken Hill Block, New South Wales, Australia, reveal distinctive geochemical signatures. Major-element data show high Al2O3 and K2O, low MgO and Na2O, and relatively high Fe2O3T MgO ratios, compared to average Early Proterozoic clastic metasediments. High field strength elements (HFSE) are especially abundant, including Nb (most 15-27 ppm), Ta (most 1.0-2.2 ppm), Th (17-36 ppm), Hf (4-15 ppm), and Zr (most 170-400 ppm); Y (33-74 ppm) is also high. Concentrations of ferromagnesian elements are generally low (Sc = < 20 ppm, Ni = ??? 62 ppm, Co = <26 ppm; Cr = most < 100 ppm). Data for rare earth elements (REEs) show high abundances of light REEs (LaCN = 116-250 ?? chondrite; LaCN = 437 in one sample), high LaCN YbCN ratios (5.6-13.9), and large negative Eu anomalies ( Eu Eu* = 0.32-0.57). The geochemical data indicate derivation of the metasedimentary rocks of the Broken Hill Group by the erosion mainly of felsic igneous (or meta-igneous) rocks. High concentrations of HFSE, Y, and REEs in the metasediments suggest a provenance dominanted by anorogenic granites and(or) rhyolites, including those with A-type chemistry. Likely sources of the metasediments were the rhyolitic to rhyodacitic protoliths of local quartz + feldspar ?? biotite ?? garnet gneisses (e.g., Potosi-type gneiss) that occur within the lower part of the Willyama Supergroup, or chemically similar basement rocks in the region; alternative sources may have included Early Proterozoic anorogenic granites and(or) rhyolites in the Mount Isa and(or) Pine Creek Blocks of northern Australia, or in the Gawler craton of South Australia. Metallogenic considerations suggest that the metasediments of the Broken Hill Block formed enriched source rocks during the generation of pegmatite-hosted deposits and concentrations of La, Ce, Nb, Ta, Th, and Sn in the region. Li, Be, B, W

  20. Cretaceous source rocks in Pakistan

    SciTech Connect

    Kari, I.B. )

    1993-02-01

    Pakistan is located at the converging boundaries of the Indian, Arabian, and Eurasian plates. Evolution of this tectonic setting has provided an array of environmental habitats for deposition of petroleum source rocks and development of structural forms. The potential Cretaceous source rocks in Central and South Indus Basin are spread over an area of about 300,000 km[sup 2]. With 2% cutoff on Total Organic Carbon, the average source rock thickness is 30-50 m, which is estimated to have generated more than 200 billion bbl of oil equivalent. To date, production of more than 30,000 bbl of oil and about 1200 million ft[sup 3] of gas per day can be directly attributed to Cretaceous source. This basin was an area of extensional tectonics during the Lower to Middle Cretaceous associated with slightly restricted circulation of the sea waters at the north-western margin of Indian Plate. Lower Cretaceous source rocks (Sembar Formation) were deposited while the basin was opening up and anoxia was prevailing. Similarly Middle to Upper Cretaceous clastics were deposited in setting favorable for preservation of organic matter. The time and depth of burial of the Cretaceous source material and optimum thermal regime have provided the requisite maturation level for generation of hydrocarbons in the basin. Central Indus basin is characterized by Cretaceous source rocks mature for gas generation. However, in South Indus Basin Cretaceous source rocks lie within the oil window in some parts and have gone past it in others.

  1. Clastic dikes of the Hatrurim basin (western flank of the Dead Sea) as natural analogues of alkaline concretes: Mineralogy, solution chemistry, and durability

    NASA Astrophysics Data System (ADS)

    Sokol, E. V.; Gaskova, O. L.; Kozmenko, O. A.; Kokh, S. N.; Vapnik, E. A.; Novikova, S. A.; Nigmatulina, E. N.

    2014-11-01

    This study shows that the mineral assemblages from clastic dikes in areas adjacent to the Dead Sea graben may be considered as natural analogues of alkaline concretes. The main infilling material of the clastic dikes is composed of well-sorted and well-rounded quartz sand. The cement of these hard rocks contains hydroxylapophyllite, tacharanite, calcium silicate hydrates, opal, calcite, and zeolite-like phases, which is indicative of a similarity of the natural cementation processes and industrial alkaline concrete production from quartz sands and industrial alkaline cements. The quartz grains exhibit a variety of reaction textures reflecting the interaction with alkaline solutions (opal and calcium hydrosilicate overgrowths; full replacement with apophyllite or thomsonite + apophyllite). The physicochemical analysis and reconstruction of the chemical composition of peralkaline Ca, Na, and K solutions that formed these assemblages reveal that the solutions evolved toward a more stable composition of zeolite-like phases, which are more resistant to long-term chemical weathering and atmospheric corrosion. The 40Ar/39Ar age of 6.2 ± 0.7 Ma obtained for apophyllite provides conclusive evidence for the high corrosion resistance of the assemblages consisting of apophyllite and zeolite-like phases.

  2. Upper Strawn (Desmoinesian) carbonte and clastic depositional environments, southeastern King County, Texas

    SciTech Connect

    Boring, T.H. )

    1990-02-01

    The Pennsylvanian upper Strawn Group of southeastern King County, Texas, provides a unique setting to study interactions between coeval carbonate and clastic deposition during the Desmoinesian. One of the most perplexing problems is the relationship of massive Pennsylvanian platform carbonates to shallow-water terrigenous clastic sediments. Within the study area, carbonate facies were deposited along the northern edge of the Knox-Baylor trough on the Spur platform, and terrigenous clastics were carried toward the Midland basin through the Knox-Baylor trough. Based on the analysis of subsurface cores, five carbonate lithofacies and four clastic lithofacies were recognized in southeastern King County, Texas. The distribution and geometry of these lithofacies are related to variations in the rate of subsidence in the Knox-Baylor trough, Pennsylvanian tectonics, deltaic progradation, avulsion, and compaction. The platform carbonates within the northern region of southeastern King County record environments within the carbonate platform complex, including middle platform, outer platform, algal mound, and platform margin. The quartzarenitic sandstones within the southern region of southeastern King County occur in a variety of complex depositional geometries, including distributary-bar fingers, lobate deltas, and offshore bars. Cores of these sandstones represent mainly the uppermost portion of the various sandstone bodies. The upper Strawn Group provides an attractive area for exploration geology. Both carbonates and clastics provide excellent reservoirs from a depth of approximately 5,000-6,000 ft. Total production within the area is over 100 million bbl of oil since the early 1940s. Multiple pay zones within a 600-ft interval also provide an added incentive for exploration. Areas within and around the Knox-Baylor trough deserve a detailed study due to these relatively shallow, unexplored, multiple pay zones.

  3. Modeling and inversion of elastic wave velocities and electrical conductivity in clastic formations with structural and dispersed shales

    NASA Astrophysics Data System (ADS)

    Aquino-López, A.; Mousatov, A.; Markov, M.; Kazatchenko, E.

    2015-05-01

    This paper presents a new approach for simulating P- and S-wave velocities, and electrical conductivity in shaly-sand rocks and determining the shale spatial distribution (dispersed and/or structural shales). In this approach, we used the effective medium method and hierarchical model for clastic formations. We treat shaly-sand formations as porous natural-composite materials containing: solid grains (such as quartz, feldspars and structural shale) and pores completely filled with a mixture of hydrocarbon, water and dispersed shale. For calculating the effective elastic properties and electrical conductivity of this composite, we have applied the multi-component self-consistent effective media approximation (EMA) method. We simulate the elastic velocities and electrical conductivity for clastic formations in two steps. Firstly, we calculate the effective properties of mixture (combination of water, hydrocarbon and dispersed shale) filling the pores. Then we find the effective elastic and electrical conductivity properties of formation constituted of solid grains (quartz and structural shale) and pores with the effective properties determined in the previous step. We considered that all components are represented by ellipsoids. The aspect ratios (shapes) of grains and pores; are defined as a porosity function obtained for the model of clean sand formations. Modeling results have demonstrated that the shapes of both shale components (dispersed and structural) weakly affect the effective elastic velocities and electrical conductivity of shaly-sand formation and can be approximated by flatted ellipsoids. The model proposed has been used to determine the volumes of dispersed and structural shales for two sets of published experimental data obtained from the cores. For determining the shale distribution, we have performed the joint inversion of the following physical properties: P-, S-wave velocities, total porosity, and total shale volume. Additionally, we have

  4. Unusual occurrence of some sedimentary structures and their significance in Jurassic transgressive clastic successions of Northern Ethiopia

    NASA Astrophysics Data System (ADS)

    Dubey, N.; Bheemalingeswara, K.

    2009-04-01

    Mesozoic sedimentary successions produced by marine transgression and regression of sea in northeastern part of Africa are well preserved in Mekelle basin of Ethiopia. Here, a typical second order sequence is well developed and preserved overlying the Precambrian basement rocks or patchy Palaeozoic sedimentary successions. Initiation of Mesozoic sedimentation in Mekelle basin has started with deposition of Adigrat Sandstone Formation (ASF). It is a retrogradational succession of siliciclastics in coastline/beach environment due to transgression of sea from southeast. ASF is followed by Antallo Limestone Formation (ALF)- an aggradational succession of carbonates in tidal flat environment; Agula Shale/Mudstone Formation (AMF); and Upper/Ambaradom Sandstone Formation (USF)- a progradational succession formed during regression in ascending order (Dubey et al., 2007). AMF is deposited in a lagoonal evaporatic environment whereas USF in a fluvial coastal margin. ASF is an aggregate of cyclically stacked two lithologies ASF1 and ASF2 produced by sea-level rise and fall of a lower order mini-cycle. ASF1 is a thick, multistoried, pink to red, friable, medium to fine grained, cross-bedded sandstone deposited in a high energy environment. ASF2 is a thin, hard and maroon colored iron-rich mudstone (ironstones) deposited in a low energy environment. ASF1 has resulted during regressive phase of the mini-cycle when rate of sedimentation was extremely high due to abundant coarser clastic supply from land to the coastal area. On the other hand, ASF2 has resulted during transgressive phase of the mini-cycle which restricted the supply of the coarser clastic to the coastal area and deposited the muddy ferruginous sediments in low energy offshore part of the basin where sedimentation rate was very low. Apart from these two major lithologies, there are also few other minor lithologies like fine-grained white sandstone, carbonate (as bands), claystone and mudstone present in ASF. ASF is

  5. Chemical composition of sawdust from lunar rock 12013 and comparison of a Java tektite with the rock.

    NASA Technical Reports Server (NTRS)

    Showalter, D. L.; Wakita, H.; Schmitt, R. A.; Gillum, D. E.; Ehmann, W. D.; Smith, R. H.

    1972-01-01

    Abundances of 11 major and minor elements and 11 trace elements have been determined by instrumental neutron activation analysis of two Apollo 12013 rock fragments, a sample of rock 12013,17 sawdust, and a Java tektite (J2). Although the abundances of major elements in tektite J2 are similar to those of rock 12013, comparison of the minor and trace elements shows that no fragment of sawdust or rock 12013 that has been analyzed to date is chemically similar to tektite glass. Rock sawdust is representative of ?whole rock' composition only if the amount of contamination from the sawing process is known. After appropriate correction for saw wire contamination, analyses of sawdust yield fairly accurate averaged elemental compositions of complex clastic lunar and other rocks.

  6. Subsurface geology of Tertiary rocks of northeastern district of Western Desert, Egypt

    SciTech Connect

    Elzarka, M.H.; Radwan, I.A.

    1983-03-01

    The lithofacies analysis of the Tertiary rocks reveals two ancient subbasins at the north and southeast of the northeastern district, Western Desert. The lithofacies of the Paleocene and early and middle Eocene sections are mainly calcareous. Shale predominates in the late Eocene rocks. The Paleocene rocks seem to have accumulated in a lagoonal environment of epineritic depths. The Paleocene rocks of the northern subbasin indicate accumulation on an unstable shelf. The Paleocene environmental conditions seem to have prevailed during the early and middle Eocene. During the late Eocene, rocks of shallow-water and current-agitated environments accumulated. The lower clastic layers of the Oligocene, having a sand/shale ratio less than one, indicate a clastic shoreline environment-lagoonal subenvironment. The Oligocene clastics are overlain by a basaltic sheet at the eastern part of the district. The middle Miocene lithofacies indicate rock accumulation in a contemporaneously subsiding basin under lagoonal or delta-front conditions at the southern part of the district. Marine stagnant-bottom-water conditions prevailed during the accumulation of the middle Miocene rocks at the norther parts. The Pliocene rocks seem to have accumulated in lagoons, where the inflow exceeded evaporation and alternating periods of exposure and flooding by either fresh or saline water of poor circulation prevailed. The tectonic instability of the district was initiated by volcancity during the late Oligocene.

  7. Talking Rocks.

    ERIC Educational Resources Information Center

    Rice, Dale; Corley, Brenda

    1987-01-01

    Discusses some of the ways that rocks can be used to enhance children's creativity and their interest in science. Suggests the creation of a dramatic production involving rocks. Includes basic information on sedimentary, igneous, and metamorphic rocks. (TW)

  8. Upper Strawn (Desmoinesian) carbonate and clastic depositional environments, SE King County, TX

    SciTech Connect

    Boring, T.H. )

    1990-05-01

    The Pennsylvanian upper Strawn Group of southeast King County, Texas, provides a unique setting to study interactions between coeval carbonate and clastic deposition during the Desmoinesian. One of the most perplexing problems is the relationship of massive Pennsylvanian platform carbonates to shallow-water marine and deltaic sediments. Within the study area carbonate facies were deposited along the northern edge of the Knox-Baylor trough on the Spur platform, and terrigenous clastics were carried toward the Midland basin through the Knox-Baylor trough. Based on the analysis of subsurface cores, five carbonate lithofacies and four clastic lithofacies were recognized in southeast King County, Texas. The distribution and geometry of these lithofacies are related to variations in the rate of subsidence in the Knox-Baylor trough, Pennsylvanian tectonics, deltaic progradation, avulsion and compaction. The platform carbonates within the northern region record environments within the carbonate platform complex, including middle platform, outer platform, algal mound, and platform margin. The quartzarenitic sandstones within the southern region occur in a variety of complex depositional geometries, including distributary bar fingers, lobate deltas, and offshore bars. The upper Strawn Group provides an attractive area for exploration geology. Both carbonates and clastics provide excellent reservoirs from a depth of approximately 5,000 to 6,000 ft. Total production since the early 1940s, within the area is over 100,000,000 bbl of oil. Multiple pay zones within a 600-ft interval also provide an added incentive for exploration. Areas within and around the Knox-Baylor trough deserve additional study due to these relatively shallow, unexplored, multiple pay zones.

  9. Neoproterozoic to Early Cambrian clastics sedimentation and stratigraphy in the Central and Southern Appalachians: An overview

    SciTech Connect

    Schwab, F.L. . Dept. of Geology)

    1993-03-01

    A clear understanding of paleogeography, tectonics, and sedimentary framework now exists for Neoproterozoic to Early Cambrian clastics in the Central and Southern Appalachians. It is based on well-constrained data on mineralogy, texture, and sedimentary structures and less precise information on age and regional variations in lithology and thickness. From 900 m.y. ago until 600 m.y. ago, tension along the eastern edge of North America produced a series of NE-SW basins (grabens and aulacogens ). These rift-related basins filled with thick, coarse, arkosic clastics (Mechum River Fm., Mt. Rogers Volc. Gp., Grandfather Mtn. Fm., portions of the Ocoee Series) mimicking the setting that later typified the Triassic of eastern North America. Coeval sequences exposed along the southeastern edge of the Blue Ridge in Va. and N.C. (Fauquier Fm., Lynchburg Gp., Ashe Fm.) define the hinge zone of a developing continental margin. Farther south in Tenn., Ga., and Ala., the picture is less clear. In latest Precambrian and Early Cambrian time, a passive Atlantic-type'' margin existed. This consisted of paired continental shelf and continental slope-rise areas (shallow water deposits of the Chilhowee Gp. and overlying muds and carbonates to the northwest; deep water clastics of the Evington Gp. and Alligator Back Fm. to the southeast). The cohesiveness of this framework argues against these tectonostratigraphic belts being considered terranes.

  10. Source rock potential of middle cretaceous rocks in Southwestern Montana

    USGS Publications Warehouse

    Dyman, T.S.; Palacas, J.G.; Tysdal, R.G.; Perry, W.J.; Pawlewicz, M.J.

    1996-01-01

    The middle Cretaceous in southwestern Montana is composed of a marine and nonmarine succession of predominantly clastic rocks that were deposited along the western margin of the Western Interior Seaway. In places, middle Cretaceous rocks contain appreciable total organic carbon (TOC), such as 5.59% for the Mowry Shale and 8.11% for the Frontier Formation in the Madison Range. Most samples, however, exhibit less than 1.0% TOC. The genetic or hydrocarbon potential (S1+S2) of all the samples analyzed, except one, yield less than 1 mg HC/g rock, strongly indicating poor potential for generating commercial amounts of hydrocarbons. Out of 51 samples analyzed, only one (a Thermopolis Shale sample from the Snowcrest Range) showed a moderate petroleum potential of 3.1 mg HC/g rock. Most of the middle Cretaceous samples are thermally immature to marginally mature, with vitrinite reflectance ranging from about 0.4 to 0.6% Ro. Maturity is high in the Pioneer Mountains, where vitrinite reflectance averages 3.4% Ro, and at Big Sky Montana, where vitrinite reflectance averages 2.5% Ro. At both localities, high Ro values are due to local heat sources, such as the Pioneer batholith in the Pioneer Mountains.

  11. Source rock potential of middle Cretaceous rocks in southwestern Montana

    SciTech Connect

    Dyman, T.S.; Palacas, J.G.; Tysdal, R.G.; Perry, W.J. Jr.; Pawlewicz, M.J.

    1996-08-01

    The middle Cretaceous in southwestern Montana is composed of a marine and nonmarine succession of predominantly clastic rocks that were deposited along the western margin of the Western Interior Seaway. In places, middle Cretaceous rocks contain appreciable total organic carbon (TOC), such as 5.59% for the Mowry Shale and 8.11% for the Frontier Formation in the Madison Range. Most samples, however, exhibit less than 1.0% TOC. The genetic or hydrocarbon potential (S{sub 1}+S{sub 2}) of all the samples analyzed, except one, yield less than 1 mg HC/g rock, strongly indicating poor potential for generating commercial amounts of hydrocarbons. Out of 51 samples analyzed, only one (a Thermopolis Shale sample from the Snowcrest Range) showed a moderate petroleum potential of 3.1 mg HC/g rock. Most of the middle Cretaceous samples are thermally immature to marginally mature, with vitrinite reflectance ranging from about 0.4 to 0.6% R{sub o}. Maturity is high in the Pioneer Mountains, where vitrinite reflectance averages 3.4% R{sub o}, and at Big Sky, Montana, where vitrinite reflectance averages 2.5% R{sub o}. At both localities, high R{sub o} values are due to local heat sources, such as the Pioneer batholith in the Pioneer Mountains.

  12. Remote sensing of some sedimentary rocks.

    NASA Technical Reports Server (NTRS)

    Brennan, P. A.; Lintz, J., Jr.

    1971-01-01

    Sedimentary rocks including varying sized clastics and carbonates were overflown by aircraft between 1966 and 1971 producing data in the ultraviolet to microwave regions of the electromagnetic spectrum. This paper reports that multispectral analysis increases the ease and rapidity of discrimination of rock types having subtle differences in physical characteristics, but fails to enhance and may degrade distinctions where physical characteristics are significantly different. Brief resumes of color and color IR photographic data are presented. Thermal infrared is found to be useful in the mapping of rock units, but limitations such as moisture variation, soil cover, and vegetation may exceed in one formation the distinction between differing lithologies. A brief review of previously published SLAR data is included for completeness. Remote sensing techniques should reduce field geological effort by as much as 50%.

  13. Chromian spinels from Apollo 14 rocks.

    NASA Technical Reports Server (NTRS)

    Steele, I. M.

    1972-01-01

    Results of electron microprobe analysis of 13 pink, isotropic, high-relief grains from Apollo 14 elastic rock 14063,14 and a lithic fragment from the 1 to 2 mm fines, 14002,7, identifying them as spinel minerals dominated by the spinel component MgAl2O4 associated with a moderate content of chromite and hercynite. The spinel is thought to have crystallized from a magma high in aluminum and low in iron, with possible crystal separation, followed by incorporation in clastic rocks by impacts. Many bulk compositions of the elastic fragments fall near the field of primary spinel in the model system An-Fo-SiO2. Experimental syntheses of Apollo 14 rocks are needed to test the suggested primary origin.

  14. Late Wisconsinan sub-glacial clastic intrusive sheets along Lake Erie bluffs, at Bradtville, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Dreimanis, Aleksis; Rappol, Martin

    1997-07-01

    Numerous clastic intrusive sheets, a few decimetres to more than 16 m long, 1-120 cm thick, and extending one to more than 25 m laterally, occur along a 350 m long section of the late Wisconsinan Catfish Creek Drift in the Lake Erie bluffs at Bradtville, southwestern Ontario. Most of them are downglacier-dipping dikes, the largest one terminating in the underlying middle Wisconsinan Tyrconnell Formation. Most dikes strike NNE-SSW, at right angles to the local direction of glacier movement during the deposition of Catfish Creek Drift. The tops of some of them are truncated or displaced downglacier by shearing. The main concentration of clastic intrusive sheets is on the upglacier side of a glaciotectonically folded anticline of Tyrconnell Formation clays and silts underlying the Catfish Creek Drift. The host sediments are Catfish Creek till, gravel, sand and silt, and Tyrconnell Formation silt and clay. Most intrusive sheets, particularly the small to medium ones, consist of massive to crudely laminated sand and silt, intruded from below by a dewatering process. The largest dike reflects in its composition mainly the adjoining or higher-lying host-sediment materials, and its main part was formed by downward infilling, or by gravity flows into an open fracture. The large dike is flanked by small laminated silty sand sheets and several small apophyses, some of them injected downward and sideways, others upward by dewatering. The clastic intrusive sheets were formed under a moving glacier, the Erie lobe, probably both at the beginning and towards the end of the deposition of Catfish Creek till. Their location and position was predetermined by glaciotectonically induced listric planar structures and zones of weakness, mainly tension fractures, that strike transverse to glacier movement and dip downglacier and also by confinement of pore-water in a permeable sediment wedge between the less pervious Tyrconnell Formation and massive Catfish Creek basal till.

  15. Experimental Determination of Clay Mineral Reactions in Clastic Reservoir Rock Resulting from the Injection of Supercritical CO2

    NASA Astrophysics Data System (ADS)

    Mangini, S. A.; Shaw, C. A.; Skidmore, M. L.

    2013-12-01

    The Cretaceous Frontier Formation of the Powder River Basin, WY has been considered as a potential reservoir for storing anthropogenic CO2. The reservoir zones are composed of fine-grained quartz and potassium feldspar rich sandstones, cemented with clay minerals (kaolinite and interlayered illite and montmorillonite). The purpose of these experiments is to determine whether susceptible minerals such as illite, montmorillonite, and potassium feldspar undergo in-situ 'weathering' reactions when exposed to the high concentrations of carbonic acid generated by the dissolution of supercritical CO2 in formation water. The transformation of these minerals has the potential to: 1.) open up pore space through dissolution; 2.) reduce pore space and/or close pore throats by precipitating new minerals, or 3.) cause little change if the reactions take place slowly. Core samples of the Frontier Formation were obtained from the USGS Core Repository in Denver, CO and their physical and mineralogical properties analyzed. Porosity and permeability of the cores have been determined by helium porosimetry and gas permeability testing. Pore space distribution was analyzed by CT scan. Mineralogy was determined by thin section analysis, X-Ray diffraction, and Scanning Electron Microscopy. Ongoing experiments will expose the cores to CO2 saturated brine in a flow-through reactor at conditions similar to those found in the subsurface (100oC and 15MPa). Changes to the chemical composition of the brine will be determined by withdrawing samples at regular intervals during the experiment and analyzing their contents with ion chromatography and colorimetry. The physical and mineralogical properties of the cores will be analyzed after each experiment and compared to the initial conditions. We will report on the results of these experiments.

  16. Clastic injection dynamics during ice front oscillations: A case example from Sólheimajökull (Iceland)

    NASA Astrophysics Data System (ADS)

    Ravier, Edouard; Buoncristiani, Jean-François; Menzies, John; Guiraud, Michel; Portier, Eric

    2015-06-01

    Soft-sediment deformation structures are being increasingly used as a tool for reconstructing palaeoenvironments and porewater pressure conditions in glacial settings. However, the potential of hydrofractures and clastic injections in the reconstruction of ice dynamics remains poorly constrained. This paper presents the results of a detailed study of a clastic injection network outcropping in the Sólheimajökull forefield (South Iceland). Sedimentological descriptions are combined with microscopic to macroscopic analyses of clastic injection geometries, sediment-fills, and cross-cutting relationships. The 250 m long and 20 m high exposure observed along the east flank of the proglacial braid plain displays alternating glaciofluvial sediments and subglacial tills, illustrating oscillations of the ice margins. These sediments are cross-cut by a dense network of injection composed of dykes propagating upward or downward, sills, and stepped sills. These clastic injections result from processes of hydrofracturing and the sediment-fills in these hydrofractures are generally laminated with an increase of grain-size towards the centre of the injections. These fracture-fill characteristics suggest multiple injection phases within the hydrofractures and an increase of porewater pressure over time. Five main generations of clastic injections showing different senses of propagation and dip directions are determined and are interpreted as forming in different environments. Per descensum clastic dykes dipping down ice demonstrate subglacial hydrofracturing underneath flowing-ice, while sills and per ascensum clastic dykes form in submarginal to marginal environments due to the decrease of ice overburden pressure. The integration of these results with the sedimentological characteristics allows the Holocene ice front oscillations of the Sólheimajökull to be reconstructed. This study demonstrates the importance of hydrofracture systems and their sediment-fills in the

  17. The paleomagnetism of clastic and precipitate deposits in limestone and dolomite caves

    SciTech Connect

    Latham, A.G. ); Ford, D.C. )

    1991-03-01

    Clastic sediments and calcite precipitates (stalagmites, flowstones, etc.) are abundant in modern limestone caves and normally are the dominant infillings in buried (paleokarst) caves. Clastic sediment fillings are chiefly of fluviatile or local breakdown origin, but lacustrine, colluvial, eolian, and glacial deposits are known. Paleomagnetism has been studied in the fluviatile and lacustrine types: (1) reversal stratigraphy aids dating of geomorphic and paleoclimatic events in the late Pliocene/Pleistocene; (2) fine magnetostratigraphy has yielded estimates of the westward drift. Calcite precipitates (speleothems) may display natural remanent magnetism of either depositional (DRM) or chemical (CRM) origin. NRMs of modern speleothems are primary, not diagenetic; CRMs are invariably associated with the degradation of surface organic matter. (1) Coarse reversal stratigraphy dates geomorphic, etc., events and erosion rates. (2) Fine stratigraphy combined with {sup 230}Th:{sup 234}U dating gives high precision estimates of secular variation, westward drift, and rate of change of geomagnetic anomalies in upper Pleistocene and Holocene deposits. Magnetostratigraphy of paleokarst speleothem fillings associated with hydrocarbons in Ordovician limestones suggest a Permian age for the karstification. Potential applications of magnetostratigraphy to paleokarst deposits of many different scales are considerable.

  18. GPR Imaging of Clastic Dikes at the Hanford Site, Hanford, Washington

    SciTech Connect

    Clement, William P.; Murray, Christopher J.

    2007-12-08

    We use ground penetrating radar (GPR) data to help determine the spatial distribution and the subsurface geometry of clastic injection dikes at the Hanford site. This information will help to improve the understanding of the hydrological role of these ubiquitous clastic dikes at the Han¬ford Site. We collected 100 MHz ground penetrating radar (GPR) 3D surface reflection data at two sites, the S-16 Pond and the Army Loop Road sites, and 2D reflection data along a 6.9 km lin¬ear transect near the Army Loop Road site. The dikes are distinguished in the GPR data by a strongly attenuated zone, disruptions in the continuity of reflections, and diffractions where reflections are disrupted. In general, the data quality is better at the Army Loop Road and Traverse sites than at the S-16 Pond site, probably due to the presence of cobbles at the S-16 Pond site. A high-moisture, fine-grained unit probably causes the strong reflections at the Army Loop Road site and the Traverse survey site. The signal penetration varies between 5 to 12 m below the land surface.

  19. Rock Finding

    ERIC Educational Resources Information Center

    Rommel-Esham, Katie; Constable, Susan D.

    2006-01-01

    In this article, the authors discuss a literature-based activity that helps students discover the importance of making detailed observations. In an inspiring children's classic book, "Everybody Needs a Rock" by Byrd Baylor (1974), the author invites readers to go "rock finding," laying out 10 rules for finding a "perfect" rock. In this way, the…

  20. Rock Art

    ERIC Educational Resources Information Center

    Henn, Cynthia A.

    2004-01-01

    There are many interpretations for the symbols that are seen in rock art, but no decoding key has ever been discovered. This article describes one classroom's experiences with a lesson on rock art--making their rock art and developing their own personal symbols. This lesson allowed for creativity, while giving an opportunity for integration…

  1. Collecting Rocks.

    ERIC Educational Resources Information Center

    Barker, Rachel M.

    One of a series of general interest publications on science topics, the booklet provides those interested in rock collecting with a nontechnical introduction to the subject. Following a section examining the nature and formation of igneous, sedimentary, and metamorphic rocks, the booklet gives suggestions for starting a rock collection and using…

  2. Science Rocks!

    ERIC Educational Resources Information Center

    Prestwich, Dorothy; Sumrall, Joseph; Chessin, Debby A.

    2010-01-01

    It all began one Monday morning. Raymond could not wait to come to large group. In his hand, he held a chunk of white granite he had found. "Look at my beautiful rock!" he cried. The rock was passed around and examined by each student. "I wonder how rocks are made?" wondered one student. "Where do they come from?"…

  3. Effects of heterogeneity and friction on the deformation and strength of rock

    SciTech Connect

    Nihei, K.T.; Myer, L.R.; Liu, Z.; Cook, N.G.W.; Kemeny, J.M.

    1994-03-01

    Experimental observations of the evolution of damage in rocks during compressive loading indicate that macroscopic failure occurs predominantly by extensile crack growth parallel or subparallel to the maximum principal stress. Extensile microcracks initiate at grain boundaries and open pores by a variety of micromechanical processes which may include grain bending, Brazilian type fracture and grain boundary sliding. Microstructural heterogeneity in grain size, strength and shape determines the magnitude of the local tensile stresses which produce extensile microcracking and the stability with which these microcracks coalesce to form macrocracks. Friction at grain boundaries and between the surfaces of microcracks reduces the strain energy available for extensile crack growth and increases the stability of microcrack growth. In clastic rocks, frictional forces may improve the conditions for extensile microcrack growth by constraining the amount of sliding and rotation of individual grains. Micromechanical models are used to investigate the effects of heterogeneity and friction on the deformation and strength of crystalline and clastic rocks.

  4. 'Escher' Rock

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks

    [figure removed for brevity, see original site] Figure 1

    This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters.

    The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water.

    Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend.

    These data were taken by the rover's alpha particle X-ray spectrometer.

  5. Clastic Breccias at the Slates Islands Complex Impact Structure, Northern Lake Superior

    NASA Technical Reports Server (NTRS)

    Dressler, B. O.; Sharpton, V. L.; Schnieders, B.; Scott, J.

    1996-01-01

    About 150 impact craters are known on Earth and each year several structures are added to this number. The general geology of the Slate Islands archipelago has been described by Sage (1991) and a short summary based on Sage's work is given in Dressler et al. (1995). The reader is referred to these publications for information on the bedrock geology of the island group. Early studies on the Slate Islands impact structure include: Halls and Grieve (1976), Grieve and Robertson (1976) and Stesky and Halls (1983). In this report, we provide a summary of the impact process as presently understood. We also present some of the results of our laboratory investigations conducted in 1995 and 1996. We describe in some detail the various clastic breccias encountered on the islands during our 1994 and 1995 field work and relate them to the various phases of the impact process. A more encompassing treatise on the breccias has been submitted for publication. (Dressler and Sharpton 1996).

  6. 'Earhart' Rock

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock informally named 'Earhart' on the lower slopes of 'Endurance Crater.' The rock was named after the pilot Amelia Earhart. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe fractures in Earhart could have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Rover team members do not have plans to investigate Earhart in detail because it is located across potentially hazardous sandy terrain. This image was taken on sol 219 (Sept. 4) by the rover's panoramic camera, using its 750-, 530- and 430-nanometer filters.

  7. Insights on frictional processes in sheared clastic marine sediments using ultrasonic nondestructive testing

    NASA Astrophysics Data System (ADS)

    Knuth, M. W.; Tobin, H. J.; Marone, C.; Ikari, M.

    2010-12-01

    We investigate changes in the elastic properties of deforming core materials recovered from the Nankai Trough Accretionary Prism along the IODP NanTroSEIZE transect. We shear clastic marine sediments while simultaneously making ultrasonic velocity measurements across the deforming layers. Examining the resulting changes in elastic moduli at the laboratory scale allows us to identify characteristic “fingerprints” of deformation style during direct-shear experiments, which may then be compared with measurements conducted at the field scale to infer how deformation is localized within the accretionary prism. Identifying relationships between hold time and attenuation may also shed light on fault healing mechanisms taking place immediately following a rupture. Together the effects of sliding rate and hold time on elastic moduli provide us with new ways of constraining the mechanical behavior of large plat-boundary settings throughout the seismic cycle. We tested intact core material, remolded layers, and disaggregated granular powders derived from a range of depths from IODP sites C0007 and C0004 penetrating the frontal thrust and a large out-of-sequence thrust in the outer prism, respectively. Samples were deformed in a double-direct shear configuration, varying first the strain rate and then subjecting the gouge layer to a series of slides and holds of increasing duration. Elastic wave propagation depends on micromechanical interactions and gouge layer strength, so as the shear zone evolves changes in elastic wavespeed provide a means to interrogate strain materials non-destructively, providing insight into frictional processes and mechanics as that deformation is taking place. Our results suggest that there are characteristic changes in P and S-wave velocity and attenuation for marine clastic to hemipelagic sediments as a function of sliding rate and hold time. Ultimately, examining variation in elastic moduli during a simulated seismic cycle may provide insight

  8. Sedimentation and tectonic implications of Cambrian-Ordovician clastics, Renville county, North Dakota

    SciTech Connect

    Mescher, P.K.; Pol, J.C.

    1985-02-01

    Cambrian-Ordovician clastics of the Deadwood Formation were studied in detail from Newporte field in Renville County, North Dakota. This small Cambrian-Ordovician oil pool was extensively cored, often to the Precambrian basement, allowing close examination of clastic deposition influenced by local basement tectonics. In Renville County, the basal unit consists of a well-rounded, fine to medium-grained glauconitic quartz sandstone. Paleohighs appear to have had a pronounced effect on Deadwood sedimentation. Sands, from quiet water settings, show poor to moderate sorting, are commonly finely laminated, and/or show traces of minor small-scale cross-bedding. In places, bedding planes are highly disrupted, suggesting intervals of intense bioturbation (Skolithos). Sands associated with paleohighs are clean, well sorted, and commonly friable. Their association with basement structure is suggestive of beach-barrier-bar sequences related to irregularly upthrown basement blocks. In one example, this clean basal sand is associated with an upthrown basement block and is sharply truncated by the pre-Winnipeg (early Ordovician) unconformity. The first unit above the basal sandstone in structurally lower wells is an anomalous conglomerate unit. Large angular basement clasts up to cobble size were viewed in core. This unit grades upward into a fine sand sequence and distally grades into a marine sand. It terminates abruptly in upthrown wells and indicates rapid fault movement and offset during middle Deadwood deposition, with development of localized fanglomerate sequences associated with fault scarps. Immediately capping this sequence is a dark-gray marine shale that thins depositionally toward paleohighs.

  9. Rock flows

    NASA Technical Reports Server (NTRS)

    Matveyev, S. N.

    1986-01-01

    Rock flows are defined as forms of spontaneous mass movements, commonly found in mountainous countries, which have been studied very little. The article considers formations known as rock rivers, rock flows, boulder flows, boulder stria, gravel flows, rock seas, and rubble seas. It describes their genesis as seen from their morphological characteristics and presents a classification of these forms. This classification is based on the difference in the genesis of the rubbly matter and characterizes these forms of mass movement according to their source, drainage, and deposit areas.

  10. Art Rocks with Rock Art!

    ERIC Educational Resources Information Center

    Bickett, Marianne

    2011-01-01

    This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

  11. Pore Type Classification on Carbonate Reservoir in Offshore Sarawak using Rock Physics Model and Rock Digital Images

    NASA Astrophysics Data System (ADS)

    Lubis, L. A.; Harith, Z. Z. T.

    2014-03-01

    It has been recognized that carbonate reservoirs are one of the biggest sources of hydrocarbon. Clearly, the evaluation of these reservoirs is important and critical. For rigorous reservoir characterization and performance prediction from geophysical measurements, the exact interpretation of geophysical response of different carbonate pore types is crucial. Yet, the characterization of carbonate reservoir rocks is difficult due to their complex pore systems. The significant diagenesis process and complex depositional environment makes pore systems in carbonates far more complicated than in clastics. Therefore, it is difficult to establish rock physics model for carbonate rock type. In this paper, we evaluate the possible rock physics model of 20 core plugs of a Miocene carbonate platform in Central Luconia, Sarawak. The published laboratory data of this area were used as an input to create the carbonate rock physics models. The elastic properties were analyzed to examine the validity of an existing analytical carbonate rock physics model. We integrate the Xu-Payne Differential Effective Medium (DEM) Model and the elastic modulus which was simulated from a digital carbonate rock image using Finite Element Modeling. The results of this integration matched well for the separation of carbonate pore types and sonic P-wave velocity obtained from laboratory measurement. Thus, the results of this study show that the integration of rock digital image and theoretical rock physics might improve the elastic properties prediction and useful for more advance geophysical techniques (e.g. Seismic Inversion) of carbonate reservoir in Sarawak.

  12. A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases in Western Europe

    NASA Astrophysics Data System (ADS)

    Simonneau, Anaëlle; Chapron, Emmanuel; Galop, Didier; Tachikawa, Kazuyo; Magny, Michel; Bard, Edouard

    2014-05-01

    The origin of both extreme flood events in Lake Ledro (southern Italian Alps) and coarse sandy layers in two disconnected lakes from the Bassies valley (Lakes Majeur and Sigriou, northern Pyrenees) have been related to the impact of snowmelt processes enhancing erosion of mountainous drainage basins (1, 2) throughout the Holocene. Because of increasing human impact on catchment erosion processes since the mid-Holocene in these western European mountain ranges, this study compares these well-dated lacustrine sequences in order to further document the influence of westerlies and of the North Atlantic Oscillation on clastic supply in contrasted lake basins. The integrative approaches performed on each site allow us to show that organic and minerogenic markers, such as non-pollen microsfossils, Rock-Eval pyrolysis or X-ray microfluorescence, are powerful tools to identify clastic sediment source areas. At Ledro, we therefore demonstrated that over the Late Holocene snowmelt-induced flood events essentially remobilized high altitude pasture areas whereas afterwards the flood events affected former forested areas from lower altitude1. In the Pyrenees, the southern slopes of lakes Majeur and Sigriou are characterized by two narrow canyons whose drainage basins are disconnected, relatively small and limited to the high altitude part of the valley of Bassiès. Our results demonstrated that the mid-late Holocene period was regularly interrupted by coarse sandy layers affecting both lakes Majeur and Sigriou and reflecting the high sensitivity of the two active canyons to intense rainfall or snowmelt periods². While extreme flood deposits in Lake Ledro during the Bronze Age period may result from the combination of both climate and human activities, contemporaneous extreme flood events in Ledro and coarse sandy layers in the Bassiès lakes, dated to AD 1710, AD1530, AD1360, AD940, AD570 and 1850, 1050, 1410, 1850, 2690, 4190, 4800 cal BP, testify of regional hydrological

  13. Opportunity Rocks!

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This high-resolution image captured by the Mars Exploration Rover Opportunity's panoramic camera shows in superb detail a portion of the puzzling rock outcropping that scientists are eagerly planning to investigate. Presently, Opportunity is on its lander facing northeast; the outcropping lies to the northwest. These layered rocks measure only 10 centimeters (4 inches) tall and are thought to be either volcanic ash deposits or sediments carried by water or wind. The small rock in the center is about the size of a golf ball.

  14. Terby's Rocks

    NASA Technical Reports Server (NTRS)

    2006-01-01

    27 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows some of the light-toned, layered, sedimentary rock outcrops in northern Terby Crater. Terby is located along the north edge of Hellas Planitia. The sedimentary rocks might have been deposited in a greater, Hellas-filling sea -- or not. Today, the rocks are partly covered by dark-toned sediment and debris.

    Location near: 27.2oS, 285.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  15. Finding a way to optimize drilling depths in clastic aquifers for geothermal energy

    NASA Astrophysics Data System (ADS)

    van Putten, M.; van Wees, J. D. A. M.; Pluymaekers, M. P. D.; Kramers, L.

    2012-04-01

    Clastic aquifers generally are marked by decreasing porosity and associated permeability with depth. Uncertainties in porosity of a few percentages can result in an order of magnitude change in permeability. Further, temperature increases with depth and is marked by an uncertainty of about 10-20%. Monte Carlo performance calculations, adopting variable temperature and porosity distributions, along with other natural uncertainties and engineering options for drilling, show that performance in doublet power and levelized costs of energy (LCOE in EUR/GJ) is most sensitive to changes in the temperature gradient and the porosity. As the temperature increases with depth while the porosity decreases with depth, these relationships show a trade-off in performance, such that a theoretical optimal depth can be found for a specific temperature gradient and porosity-depth curve, and associated porosity-permeability relationship. The optimal drilling depth is at the depth level where the LCOE are minimal. In mature oil and gas basin areas, such as the Netherlands, it is possible to obtain relationships of porosity and underlying permeability as a function of depth. Therefore, the applicability for establishing and using an optimal depth has been tested for a clastic aquifer in the Rotliegend stratigraphic group in the Netherlands. This aquifer has high geothermal potential and is subject to many exploration activities. Temperature gradient and porosity-depth trends (and underlying uncertainties) for this aquifer have been adopted from the national geothermal information system ThermoGIS (www.thermogis.nl). For the performance calculation of doublet power and LCOE an in-house techno-economical performance assessment (TEPA) tool called DoubletCalc has been used. The results show that optimal depth corresponds to a pronounced and sharp minimum in LCOE. Its depth depends strongly on the actual porosity-depth relationship and ranges between 1.5 and 3 km. Remarkably, variations in

  16. Rock Garden

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This false color composite image of the Rock Garden shows the rocks 'Shark' and 'Half Dome' at upper left and middle, respectively. Between these two large rocks is a smaller rock (about 0.20 m wide, 0.10 m high, and 6.33 m from the Lander) that was observed close-up with the Sojourner rover (see PIA00989).

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  17. Origin of bentonites and clastic sediments of the Paleocene Basilika Formation, Svalbard

    NASA Astrophysics Data System (ADS)

    Elling, Felix; Spiegel, Cornelia; Estrada, Solveig; Davis, Donald; Reinhardt, Lutz; Henjes-Kunst, Friedhelm; Allroggen, Niklas; Dohrmann, Reiner; Piepjohn, Karsten; Lisker, Frank

    2016-07-01

    The Paleocene was a time of transition for the Arctic, with magmatic activity of the High Arctic Large Igneous Province giving way to magmatism of the North Atlantic Large Igneous Province in connection to plate tectonic changes in the Arctic and North Atlantic. In this study we investigate the Paleocene magmatic record and sediment pathways of the Basilika Formation exposed in the Central Tertiary Basin of Svalbard. By means of geochemistry, Sm-Nd isotopic signatures and zircon U-Pb geochronology we investigate the characteristics of several bentonite layers contained in the Basilika Formation, as well as the provenance of the intercalated clastic sediments. Our data show that the volcanic ash layers of the Basilika Formation, which were diagenetically altered to bentonites, originate from alkaline continental-rift magmatism such as the last, explosive stages of the High Arctic Large Igneous Province in North Greenland and the Canadian Arctic. The volcanic ash layers were deposited on Svalbard in a flat shelf environment with dominant sediment supply from the east. Dating of detrital zircons suggests that the detritus was derived from Siberian sources, primarily from the Verkhoyansk Fold-and-Thrust Belt, which would require transport over ~3000 km across the Arctic.

  18. Clastic pipe characteristics and distributions throughout the Colorado Plateau: Implications for paleoenvironment and paleoseismic controls

    NASA Astrophysics Data System (ADS)

    Wheatley, D. F.; Chan, M. A.; Sprinkel, D. A.

    2016-10-01

    Clastic pipes occur throughout much of the Phanerozoic strata of the Colorado Plateau and provide a unique opportunity to test the validly of various deformation and triggering mechanism hypotheses in the context of their tectono-stratigraphic and paleoenvironmental settings. Pipes dominantly occur in Jurassic strata and preferentially in eolian (especially interdune), sabkha, and fluvial deposits because these sediments contained interbedded fine-grained and water-saturated, high-porosity, coarse-grained facies. The greatest geographic concentrations of pipes occur in three trends: (1) a northeast trend from the Lake Powell to Moab areas of southern and southeastern Utah, (2) an east-west trend in northern Arizona within and north of the Grand Canyon, and (3) a west-northwest-east-southeast trend along Interstate 40 west of Albuquerque, New Mexico. Many pipes formed due to liquefaction and fluidization and were potentially triggered by seismic activity originating from basement-cored uplifts within the Colorado Plateau, although other trigger mechanisms cannot be completely eliminated. Some breccia pipes within northern Arizona that are rooted in karst are the exception to this interpretation. Pipes possess unique depositional and triggering requirements and thus provide an excellent opportunity to understand the interplay of sedimentology and tectonics within continental systems.

  19. Clastic diversion by fold salients and blind thrust ridges in coal-swamp development

    SciTech Connect

    Wise, D.U. ); Belt, E.S. ); Lyons, P.C. )

    1991-05-01

    Abrupt shifts from single widespread coal swamps to coarse siliciclastic alluvial channel deposits occur in at least five coal beds and zones within the Pennsylvania Allegheny Formation. One of these, the Upper Freeport coal zone, was deposited over and area at least 200 {times} 200 km with a spacing of alluvial channels one-half to possibly one-fifth that of the immediately overlying coarse clastics. All these shifts occured next to the rising Appalachian orogen, far from the eustatic effects of a marine shoreline. Recent models relating coal-swamp formation to isostatic warping of orogenic forelands by tectonic loads surely apply to this environment, but they seem to need an additional, more delicate mechanism to produce such abrupt but widespread switches in grain size and drainage spacing. The authors propose that irregularities in the advancing front folds and blind thrusts caused temporary geomorphic diversions into the recessed areas and allowed a widespread coal swamp to form in the sedimentary shadow of the salients, a shadowing process that is occurring today in the central Zagros Mountains of Iraq and Iran.

  20. Organic facies and systems tracts: Implications for source rock preservation and prediction

    SciTech Connect

    Kosters, E.C.; Vanderzwaan, F.J.; Gijsbert, J. )

    1993-09-01

    Sequence stratigraphy is concerned with making predictions about reservoirs ahead of the drill, however, little attention has been paid to the configuration of organic-rich facies of source rock quality. We suggest that preservation of source rock type facies in clastic systems is mutually exclusive and time successive. The main database is a collection of cores and other samples through the Holocene Rhone delta. The early Holocene Transgressive Systems Tract (TST) contains five levels of channelization. The most significant peat bed is located immediately landward of the shoreline of maximum transgression (SMT). The Highstand Systems Tract (HST) consists of two parasequences, containing mostly laterally continuous strandplain complexes without peat. In addition to sufficient accommodation space, an important control on formation of fresh-water peats and organic-rich shelf muds is availability of river-induced nutrients. Peat quality, however, is best without riverine clastics. In a delta plain, a balance between these two controls may be reached when river-fed nutrients are trapped there indirectly. The potential for such a condition arises in a TST setting. On the shelf, eutrophication of marine habitats is also controlled by river-fed nutrients, but excess river clastics are detrimental to marine source rock quality. A balance between these two controls may be reached in HST settings where fine-grained riverine clastics are forced onto the shelf rather than in the delta plain. In this case, nutrient supply to the shelf results in large quantities of marine biomass. This biomass becomes sufficiently concentrated due to moderate fine-grained riverine sedimentation which guarantees burial and preservation. Thus, varying river-water and nutrient supply in TST and HST settings seems to control large-scale preservation patterns of both continental and marine organics. This hypothesis suggests further potential for using sequence stratigraphy for source rock occurrence.

  1. Tektite-bearing, deep-water clastic unit at the Cretaceous-Tertiary boundary in northeastern Mexico

    NASA Technical Reports Server (NTRS)

    Smit, J.; Montanari, A.; Swinburne, N. H.; Alvarez, W.; Hildebrand, A. R.; Margolis, S. V.; Claeys, P.; Lowrie, W.; Asaro, F.

    1992-01-01

    The hypothesis of Cretaceous-Tertiary (K-T) boundary impact on Yucatan, Mexico, predicts that nearby sites should show evidence of proximal impact ejecta and disturbance by giant waves. An outcrop along the Arroyo el Mimbral in northeastern Mexico contains a layered clastic unit up to 3 m thick that interrupts a biostratigraphically complete pelagic-marl sequence deposited at more than 400 m water depth. The marls were found to be unsuitable for determining magnetostratigraphy, but foraminiferal biostratigraphy places the clastic unit precisely at the K-T boundary. We interpret this clastic unit as the deposit of a megawave or tsunami produced by an extraterrestrial impact. The clastic unit comprises three main subunits. (1) The basal "spherule bed" contains glass in the form of tektites and microtektites, glass spherules replaced by chlorite-smectite and calcite, and quartz grains showing probable shock features. This bed is interpreted as a channelized deposit of proximal ejecta. (2) A set of lenticular, massive, graded "laminated beds" contains intraclasts and abundant plant debris, and may be the result of megawave backwash that carried coarse debris from shallow parts of the continental margin into deeper water. (3) At the top, several thin "ripple beds" composed of fine sand are separated by clay drapes; they are interpreted as deposits of oscillating currents, perhaps a seiche. An iridium anomaly (921 +/- 23 pg/g) is observed at the top of the ripple beds. Our observations at the Mimbral locality support the hypothesis of a K-T impact on nearby Yucatan.

  2. Tektite-bearing, deep-water clastic unit at the Cretaceous-Tertiary boundary in northeastern Mexico.

    PubMed

    Smit, J; Montanari, A; Swinburne, N H; Alvarez, W; Hildebrand, A R; Margolis, S V; Claeys, P; Lowrie, W; Asaro, F

    1992-02-01

    The hypothesis of Cretaceous-Tertiary (K-T) boundary impact on Yucatán, Mexico, predicts that nearby sites should show evidence of proximal impact ejecta and disturbance by giant waves. An outcrop along the Arroyo el Mimbral in northeastern Mexico contains a layered clastic unit up to 3 m thick that interrupts a biostratigraphically complete pelagic-marl sequence deposited at more than 400 m water depth. The marls were found to be unsuitable for determining magnetostratigraphy, but foraminiferal biostratigraphy places the clastic unit precisely at the K-T boundary. We interpret this clastic unit as the deposit of a megawave or tsunami produced by an extraterrestrial impact. The clastic unit comprises three main subunits. (1) The basal "spherule bed" contains glass in the form of tektites and microtektites, glass spherules replaced by chlorite-smectite and calcite, and quartz grains showing probable shock features. This bed is interpreted as a channelized deposit of proximal ejecta. (2) A set of lenticular, massive, graded "laminated beds" contains intraclasts and abundant plant debris, and may be the result of megawave backwash that carried coarse debris from shallow parts of the continental margin into deeper water. (3) At the top, several thin "ripple beds" composed of fine sand are separated by clay drapes; they are interpreted as deposits of oscillating currents, perhaps a seiche. An iridium anomaly (921 +/- 23 pg/g) is observed at the top of the ripple beds. Our observations at the Mimbral locality support the hypothesis of a K-T impact on nearby Yucatán.

  3. Igneous rocks of the West Sakhalin Terrane of Sakhalin Island

    NASA Astrophysics Data System (ADS)

    Grannik, V. M.

    2016-10-01

    It has been determined that the Rozhdestvenka Formation of the West Sakhalin Terrane composed of Late Mesozoic igneous rocks is a fragment of the accretionary prism of the Rebun-Kabato-Moneron-Samarga island-arc system. Volcanic eruptions, as well as destruction of the Rebun-Kabato-Moneron-Samarga island-arc and the East Sikhote-Alin volcano plutonic marginal continental belt, were the sources of pyroclastic and clastic material entering the sedimentary basin, where the Pobedinsk and Krasnoyarka suites of the West Sakhalin Terrane were formed.

  4. 'Wopmay' Rock

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This approximate true-color image taken by NASA's Mars Exploration Rover Opportunity shows an unusual, lumpy rock informally named 'Wopmay' on the lower slopes of 'Endurance Crater.' The rock was named after the Canadian bush pilot Wilfrid Reid 'Wop' May. Like 'Escher' and other rocks dotting the bottom of Endurance, scientists believe the lumps in Wopmay may be related to cracking and alteration processes, possibly caused by exposure to water. The area between intersecting sets of cracks eroded in a way that created the lumpy appearance. Rover team members plan to drive Opportunity over to Wopmay for a closer look in coming sols. This image was taken by the rover's panoramic camera on sol 248 (Oct. 4, 2004), using its 750-, 530- and 480-nanometer filters.

  5. High resolution sequence stratigraphy of Miocene deep-water clastic outcrops, Taranaki coast, New Zealand

    SciTech Connect

    King, P.R.; Browne, G.H.; Slatt, R.M.

    1995-08-01

    Approximately 700m of deep water clastic deposits of Mt. Messenger Formation are superbly exposed along the Taranaki coast of North Island, New Zealand. Biostratigraphy indicates the interval was deposited during the time span 10.5-9.2m.y. in water depths grading upward from lower bathyal to middle-upper bathyal. This interval is considered part of a 3rd order depositional sequence deposited under conditions of fluctuating relative sea-level, concomitant with high sedimentation rates. Several 4th order depositional sequences, reflecting successive sea-level falls, are recognized within the interval. Sequence boundaries display a range of erosive morphologies from metre-wide canyons to scours several hundred metres across. All components of a generic lowstand systems tract--basin floor fan, channel-levee complex and progading complex--are present in logical and temporal order. They are repetitive through the interval, with the relatively shallower-water components becoming more prevalent upward. Basin floor fan lithologies are mainly m-thick, massive and convolute-bedded sandstones that alternate with cm- and dm-thick massive, horizontally-stratified and ripple-laminated sandstones and bioturbated mudstones. Channel-levee deposits consist of interleaving packages of thin-bedded, climbing-rippled and parallel-laminated sandstones and millstones; infrequent channels are filled with sandstones and mudstones, and sometimes lined with conglomerate. Thin beds of parallel to convoluted mudstone comprise prograding complex deposits. Similar lowstand systems tracts can be recognized and correlated on subsurface seismic reflection profiles and wireline logs. Such correlation has been aided by a continuous outcrop gamma-ray fog obtained over most of the measured interval. In the adjacent Taranaki peninsula, basin floor fan and channel-levee deposits comprise hydrocarbon reservoir intervals. Outcrop and subsurface reservior sandstones exhibit similar permeabilities.

  6. Classic Rock

    ERIC Educational Resources Information Center

    Beem, Edgar Allen

    2004-01-01

    While "early college" programs designed for high-school-age students are beginning to proliferate nationwide, a small New England school has been successfully educating teens for nearly four decades. In this article, the author features Simon's Rock, a small liberal arts college located in the Great Barrington, Massachusetts, that has…

  7. Poohbear Rock

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image, taken by Sojourner's front right camera, was taken when the rover was next to Poohbear (rock at left) and Piglet (not seen) as it looked out toward Mermaid Dune. The textures differ from the foreground soil containing a sorted mix of small rocks, fines and clods, from the area a bit ahead of the rover where the surface is covered with a bright drift material. Soil experiments where the rover wheels dug in the soil revealed that the cloudy material exists underneath the drift.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  8. White Rock

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 19 April 2002) The Science 'White Rock' is the unofficial name for this unusual landform which was first observed during the Mariner 9 mission in the early 1970's. As later analysis of additional data sets would show, White Rock is neither white nor dense rock. Its apparent brightness arises from the fact that the material surrounding it is so dark. Images from the Mars Global Surveyor MOC camera revealed dark sand dunes surrounding White Rock and on the floor of the troughs within it. Some of these dunes are just apparent in the THEMIS image. Although there was speculation that the material composing White Rock could be salts from an ancient dry lakebed, spectral data from the MGS TES instrument did not support this claim. Instead, the White Rock deposit may be the erosional remnant of a previously more continuous occurrence of air fall sediments, either volcanic ash or windblown dust. The THEMIS image offers new evidence for the idea that the original deposit covered a larger area. Approximately 10 kilometers to the southeast of the main deposit are some tiny knobs of similarly bright material preserved on the floor of a small crater. Given that the eolian erosion of the main White Rock deposit has produced isolated knobs at its edges, it is reasonable to suspect that the more distant outliers are the remnants of a once continuous deposit that stretched at least to this location. The fact that so little remains of the larger deposit suggests that the material is very easily eroded and simply blows away. The Story Fingers of hard, white rock seem to jut out like icy daggers across a moody Martian surface, but appearances can be deceiving. These bright, jagged features are neither white, nor icy, nor even hard and rocky! So what are they, and why are they so different from the surrounding terrain? Scientists know that you can't always trust what your eyes see alone. You have to use other kinds of science instruments to measure things that our eyes can

  9. Bed-form climb models to analyze geometry and preservation potential of clastic facies and erosional surfaces

    SciTech Connect

    Larue, D.K.; Martinez, P.A.

    1989-01-01

    Based on a combination of Walther's Law of Facies and bed-form climb theory, the authors propose a model that explains how erosion surfaces and vertical sequences of clastic strata are preserved where deposition occurs in channelized or locally erosional environments including fluvial and submarine-channel deposits, barred beaches, and transgressive coastlines. the model considers both lateral and vertical migration of a scour surface and its associated depositional products. As in studies of bed-form climb, they recognize subcritical, critical, and supercritical climb of scour surfaces relative to adjacent depositional forms. 12 figures.

  10. Evidence of clastic evaporites in the canyons of the Levant basin (Israel): implications for the Messinian salinity crisis

    NASA Astrophysics Data System (ADS)

    Lugli, Stefano; Schreiber, B. Charlotte; Gvirtzman, Zohar; Manzi, Vinicio; Roveri, Marco

    2013-04-01

    The recognition of widespread and thick evaporite deposits below the floor of the Mediterranean Sea has boosted a long standing controversy concerning their depositional setting (shallow versus deep) and their correlation with the onshore sequences. Until a new scientific campaign might be launched to cross those deposits, the discussion is still open to speculation. Many Messinian evaporitic deposits have been interpreted as primary precipitates in very shallow-water or coastal environments, thus favouring the idea of a desiccated Mediterranean basin (Hsu et al., 1973). Recent studies have questioned this interpretation (Hardie and Lowenstein, 2004) and widespread, thick, clastic evaporite facies have been identified in the Mediterranean (Manzi et al., 2005). These clastic deposits are not compatible with a desiccation model as they were clearly emplaced by fully subaqueous, deep-water processes, ranging from submarine slides, to high- and low-density gravity flows. One of the most relevant areas for the understanding of the salinity crisis is the Levant basin where the Messinian evaporites partially fill some of the erosional features (canyons) considered to have formed as a consequence of significant drawdown related to the desiccation of the Mediterranean Sea (up to - 850 m, Druckman et al., 1995). Our complete revisitation of the available cores from onshore Israel cutting through the sedimentary filling of the Messinian canyons (Afiq 1, Ashdod 2, Be'eri Sh1, Be'eri Sh4, Jaffa 1 and Talme-Yaffe 3) revealed exclusively clastic sulfate facies. This is the first direct evidence that the Lower Evaporite Unit offshore Israel may actually consist of deep-water resedimented evaporites that were originally deposited on the margin of the Levant Basin. References Druckman Y., Buchbinder B., Martinotti G.M., Tov R.S., Aharon P., 1995. The buried Afiq Canyon (eastern Mediterranean, Israel): a case study of a Tertiary submarine canyon exposed in Late Messinian times

  11. Influence of substrate rocks on Fe-Mn crust composition

    USGS Publications Warehouse

    Hein, J.R.; Morgan, C.L.

    1999-01-01

    Principal Component and other statistical analyses of chemical and mineralogical data of Fe-Mn oxyhydroxide crusts and their underlying rock substrates in the central Pacific indicate that substrate rocks do not influence crust composition. Two ridges near Johnston Atoll were dredged repetitively and up to seven substrate rock types were recovered from small areas of similar water depths. Crusts were analyzed mineralogically and chemically for 24 elements, and substrates were analyzed mineralogically and chemically for the 10 major oxides. Compositions of crusts on phosphatized substrates are distinctly different from crusts on substrates containing no phosphorite. However, that relationship only indicates that the episodes of phosphatization that mineralized the substrate rocks also mineralized the crusts that grew on them. A two-fold increase in copper contents in crusts that grew on phosphatized clastic substrate rocks, relative to crusts on other substrate rock types, is also associated with phosphatization and must have resulted from chemical reorganization during diagenesis. Phosphatized crusts show increases in Sr, Zn, Ca, Ba, Cu, Ce, V, and Mo contents and decreases in Fe, Si, and As contents relative to non-phosphatized crusts. Our statistical results support previous studies which show that crust compositions reflect predominantly direct precipitation from seawater (hydrogenetic), and to lesser extents reflect detrital input and diagenetic replacement of parts of the older crust generation by carbonate fluorapatite.

  12. Stratigraphic analysis of the carboniferous rocks of the Central Appalachian Basin

    SciTech Connect

    Chesnut, D.R. Jr.

    1988-01-01

    A series of seven cross sections was constructed across part of the Central Appalachian Basin in Kentucky, Tennessee, Virginia, West Virginia, and Ohio. Information used to make these sections included well logs, coal-company core descriptions, measured sections, and mapped surface geology. Newly discovered surface and subsurface structural features such as faults, folds, and flexures, are described. A new, unofficial lithostratigraphic nomenclature was introduced to illustrate the stratigraphic framework, and a regional unconformity was interpreted to occur between the Pennsylvanian Pocahontas Formation and the Pennsylvanian New River Formation. The cross sections reveal that sequential truncation of formations below the unconformity occurs t the northwest in the basin. A regional unconformity and biostratigraphic evidence indicate that the Carboniferous rocks were deposited in a series of several small-scale environmental continua. Pennsylvanian rocks overlying the regional unconformity sequentially overlap the underlying rocks to the northwest in the basin. Belts of quartzose sandstones (Lee Formation) within the overlying rocks, are oriented northeast-southwest. Succeeding sandstone belts onlap the unconformity to the northwest within the basin. A fluvial origin is suggested for the quartzose, conglomeratic sands of the Lee Formation. The source for these sands may have been reworked sediments derived from the Old Red Sandstone continent to the northwest in Canada. The remaining Pennsylvanian coal-bearing clastic rocks (Breathitt Group) were deposited as clastic wedges derived from the east and southeast on coastal lowlands.

  13. Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    6 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcrops of sedimentary rocks in a crater located just north of the Sinus Meridiani region. Perhaps the crater was once the site of a martian lake.

    Location near: 2.9oN, 359.0oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  14. Routing of terrigenous clastics to oceanic basins in the southern Gulf of California, inherited from features of the pre-spreading protogulf

    NASA Astrophysics Data System (ADS)

    Lonsdale, P.; Kluesner, J. W.

    2010-12-01

    The southern protogulf was a Miocene belt of continental rupture bounded on the northeast by the Sierra Madre Occidental (SMO) volcanic plateau, and on the southeast by the Main Gulf Escarpment of the Baja California (BC) rift shoulder. Since no later than 8-9Ma, before the depression became a deep inlet of the Pacific, the southern protogulf has hosted the principal shear zone between the Pacific and North American plates. As BC gradually acquired Pacific-plate motion, its vector wrt North America rotated and made the shear zone transtensional, leading to the development of several types of pull-apart basins. Some of them, at right steps between en echelon faults, evolved into the oceanic basins that are now the principal Gulf depocenters. Recent geophysical mapping and geologic sampling in the southern Gulf has clarified the location, structures, and composition of the oceanic/continental crustal boundary, and the mechanisms and routes by which terrigenous clastics reach the intracontinental and oceanic basins.Longitudinal (northwest-southeast) thermohaline and tidal currents transport significant volumes of hemipelagic sediment across the floors of gulf basins, but most of the coarser terrigenous clastics arrive there in density flows, primarily turbidity currents that have built channeled deep-sea fans at the mouths of canyons in the continental slopes. Mapped patterns of submarine canyons, channels and fans confirm that turbidity-current transport has primarily been from the northeast margin, which has permanent mainland rivers with large catchments in the SMO. Most of the arid BC peninsula, with ephemeral-stream drainage directed toward the Pacific, contributes little terrigenous input to the deep-water gulf basins, except in the far south: more than a third of the elevated Cabo Block drains into the gulf, building a large fan on the northwest side of Alarcon Basin. The canyons feeding this fan, cut through crystalline rock and probably subaerial in origin

  15. Rock mechanics. Second edition

    SciTech Connect

    Jumikis, A.R.

    1983-01-01

    Rock Mechanics, 2nd Edition deals with rock as an engineering construction material-a material with which, upon which, and within which civil engineers build structures. It thus pertains to hydraulic structures engineering; to highway, railway, canal, foundation, and tunnel engineering; and to all kinds of rock earthworks and to substructures in rock. Major changes in this new edition include: rock classification, rock types and description, rock testing equipment, rock properties, stability effects of discontinuity and gouge, grouting, gunite and shotcrete, and Lugeon's water test. This new edition also covers rock bolting and prestressing, pressure-grouted soil anchors, and rock slope stabilization.

  16. Comparative palynology of clastics and lignites from the Manning Formation, Jackson Group, Upper Eocene, Grimes County, TX

    SciTech Connect

    Gennett, J.A.

    1996-09-01

    The 3500 lignite seam at the Gibbons Creek Mine in Grimes County, TX was sampled for pollen and spores at 10 cm intervals. The majority of samples are dominated (to 60%) by Momipites from the Juglandaceae (walnut family), as is typical of Jackson Group sediments. Other palynomorph taxa vary systematically, with a peak of pollen of the freshwater tree Nyssa (blackgum) and associated Rboipites angustus (to 17%) occurring at the base. Higher in the seam, increase (to 55%) of Cupuliferoipollenites (a chestnut-like grain) and Cyrillaceae-pollenites? ventosus (to 7%) percentages may indicate a higher salinity environment. A Chrysophyllum (satin leaf) peak (to 25%) near the top of the seam suggests relatively shallow fresh-water conditions. Core samples from an interval above the lignites represent a transgressive-regressive cycle in inner shelf clastics. These samples were taken at 40 cm or greater intervals and reveal the regional pollen flora. Although minor changes occur, palynomorph spectra are for the most part homogenous. The dominant grain is again Momipites coryloides, but in general percentages are lower (to 35%). Cupuliferoipollenites (to 17%), Chrysophyllum (to 5%), and Rhoipites angustus (to 3%) are not less important, but do not peak as they do in the lignite spectra. Palm leaf megafossils; in one sample suggest a clastic wetland; in this sample palm pollen (mostly Arecipites, representing the modern saw palmetto) reaches 73%. Another sample contains high (26%) percentages of the fern spore Lygodiumsporites adriennis. High percentages of these two taxa do not occur in the lignite samples.

  17. Rock Driller

    NASA Technical Reports Server (NTRS)

    Peterson, Thomas M.

    2001-01-01

    The next series of planetary exploration missions require a method of extracting rock and soil core samples. Therefore a prototype ultrasonic core driller (UTCD) was developed to meet the constraints of Small Bodies Exploration and Mars Sample Return Missions. The constraints in the design are size, weight, power, and axial loading. The ultrasonic transducer requires a relatively low axial load, which is one of the reasons this technology was chosen. The ultrasonic generator breadboard section can be contained within the 5x5x3 limits and weighs less than two pounds. Based on results attained the objectives for the first phase were achieved. A number of transducer probes were made and tested. One version only drills, and the other will actually provide a small core from a rock. Because of a more efficient transducer/probe, it will run at very low power (less than 5 Watts) and still drill/core. The prototype generator was built to allow for variation of all the performance-effecting elements of the transducer/probe/end effector, i.e., pulse, duty cycle, frequency, etc. The heart of the circuitry is what will be converted to a surface mounted board for the next phase, after all the parameters have been optimized and the microprocessor feedback can be installed.

  18. Stratigraphy of Slick Rock district and vicinity, San Miguel and Dolores Counties, Colorado

    USGS Publications Warehouse

    Shawe, Daniel R.; Simmons, George C.; Archbold, Norbert L.

    1968-01-01

    The Slick Rock district covers about 570 square miles in western San Miguel and Dolores Counties, in southwestern Colorado. It is at the south edge of the salt-anticline region of southwestern Colorado and southeastern Utah and of the Uravan mineral belt.Deposition of Paleozoic sedimentary rocks in the district and vicinity was principally controlled by development of the Paradox Basin, and of Mesozoic rocks by development of a depositional basin farther west. The Paleozoic rocks generally are thickest at the northeast side of the Paradox Basin in a northwest- trending trough which seems to be a wide graben in Precambrian igneous and metamorphic basement rocks; Mesozoic rocks generally thicken westward and southwestward from the district.Sedimentary rocks rest on a Precambrian basement consisting of a variety of rocks, including granite and amphibolite. The surface of the Precambrian rocks is irregular and generally more than 2,000 feet below sea level and 7,000-11,000 feet below the ground surface. In the northern part of the district the Precambrian surface plunges abruptly northeastward into the trough occupying the northeast side of the Paradox Basin, and in the southern part it sags in a narrow northeasterly oriented trough. Deepening of both troughs, or crustal deformation in their vicinity, influenced sedimentation during much of late Paleozoic and Mesozoic time.The maximum total thickness of sedimentary rocks underlying the district is 13,000 feet, and prior to extensive erosion in the late Tertiary and the Quaternary it may have been as much as about 18,000 feet. The lower 5,000 feet or more of the sequence of sedimentary rocks consists of arenaceous strata of early Paleozoic age overlain by dominantly marine carbonate rocks and evaporite beds interbedded with lesser amounts of clastic sediments of late Paleozoic age. Overlying these rocks is about 4,500 feet of terrestrial clastic sediments, dominantly sandstone with lesser amounts of shale, mudstone

  19. Compilation of Mineral Resource Data for Mississippi Valley-Type and Clastic-Dominated Sediment-Hosted Lead-Zinc Deposits

    USGS Publications Warehouse

    Taylor, Ryan D.; Leach, David L.; Bradley, Dwight C.; Pisarevsky, Sergei A.

    2009-01-01

    This report contains a global compilation of the mineral resource data for sediment-hosted lead-zinc (SH Pb-Zn) deposits. Sediment-hosted lead-zinc deposits are historically the most significant sources of lead and zinc, and are mined throughout the world. The most important SH Pb-Zn deposits are hosted in clastic-dominated sedimentary rock sequences (CD Pb-Zn) that are traditionally called sedimentary exhalative (SEDEX) deposits, and those in carbonate-dominated sequences that are known as Mississippi Valley-type (MVT) Pb-Zn deposits. In this report, we do not include sandstone-Pb, sandstone-hosted Pb, or Pb-Zn vein districts such as those in Freiberg, Germany, or Coeur d'Alene, Idaho, because these deposits probably represent different deposit types (Leach and others, 2005). We do not include fracture-controlled deposits in which fluorite is dominant and barite typically abundant (for example, Central Kentucky; Hansonburg, N. Mex.) or the stratabound fluorite-rich, but also lead- and zinc-bearing deposits, such as those in southern Illinois, which are considered a genetic variant of carbonate-hosted Pb-Zn deposits (Leach and Sangster, 1993). This report updates the Pb, Zn, copper (Cu), and silver (Ag) grade and tonnage data in Leach and others (2005), which itself was based on efforts in the Canadian Geological Survey World Minerals Geoscience Database Project (contributions of D.F. Sangster to Sinclair and others, 1999). New geological or geochronological data, classifications of the tectonic environment in which the deposits formed, and key references to the geology of the deposits are presented in our report. Data for 121 CD deposits, 113 MVT deposits, and 6 unclassified deposits that were previously classified as either SEDEX or MVT in the Leach and others (2005) compilation, are given in appendix table A1. In some cases, mineral resource data were available only for total district resources, but not for individual mines within the district. For these

  20. Lunar Rocks

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The second manned lunar landing mission, Apollo 12 launched from launch pad 39-A at Kennedy Space Center in Florida on November 14, 1969 via a Saturn V launch vehicle. The Saturn V vehicle was developed by the Marshall Space Flight Center (MSFC) under the direction of Dr. Wernher von Braun. Aboard Apollo 12 was a crew of three astronauts: Alan L. Bean, pilot of the Lunar Module (LM), Intrepid; Richard Gordon, pilot of the Command Module (CM), Yankee Clipper; and Spacecraft Commander Charles Conrad. The LM, Intrepid, landed astronauts Conrad and Bean on the lunar surface in what's known as the Ocean of Storms while astronaut Richard Gordon piloted the CM, Yankee Clipper, in a parking orbit around the Moon. Lunar soil activities included the deployment of the Apollo Lunar Surface Experiments Package (ALSEP), finding the unmanned Surveyor 3 that landed on the Moon on April 19, 1967, and collecting 75 pounds (34 kilograms) of rock samples, some of which can be seen in this photograph. Apollo 12 safely returned to Earth on November 24, 1969.

  1. Breccia 66055 and related clastic materials from the Descartes region, Apollo 16

    NASA Technical Reports Server (NTRS)

    Fruchter, J. S.; Kridelbaugh, S. J.; Robyn, M. A.; Goles, G. G.

    1974-01-01

    Trace and major element contents obtained by instrumental neutron activation are reported for a number of Apollo 16 soil samples and miscellaneous breccia fragments. In addition, data obtained by instrumental neutron activation and electron microprobe techniques along with petrographic descriptions are presented for selected subsamples of breccia 66055. The compositions of our soil samples can be modeled by mixtures of various amounts of anorthosite, anorthositic gabbro and low-K Fra Mauro basalt components. These mixtures are typical of those found in a number of petrographic surveys of the fines. Breccia 66055 is a complex regolith breccia which consists of at least four distinct types of microbreccias. No systematic relation with respect to stratigraphic age among the various microbreccia types was observed. Compositionally and texturally, the clasts which compose breccia 66055 are similar to a number of previously reported rock types from the Apollo 16 area. The entire breccia appears to have undergone a complex history of thermal metamorphism. We conclude from the study of these samples that the Cayley Formation is probably homogeneous in its gross compositional and petrographic aspects.

  2. The combined effects of eustasy, tectonism, and clastic influx on the development of Pennsylvanian cyclic carbonates, southern Sangre de Cristo Mountains, New Mexico

    SciTech Connect

    Gong Shouyeh; Humphrey, J.D. )

    1991-03-01

    Pennsylvania cyclothems are well documented on stable continental shelves and the cyclicity has generally been attributed to glacio-eustasy. As a contrast, Atokan-Desmoinesian cyclic carbonates of the southern Sangre de Cristo Mountains developed in a tectonically active foreland basin, formed by thrusting along the Picuris-Pecos fault during early Pennsylvanian time. Strata exposed in two sections (Dalton Bluff, 260 m; Johnson Mesa, 340 m) are characterized by (1) shallowing-upward cycles, (2) cycles of variable thickness (5-20 m), (3) incomplete cycles, (4) cycles interrupted by terrigenous clastic input, and (5) noncyclic intervals. Allocyclic mechanisms alone cannot fully explain these observations; the authors herein propose that a complex interplay among eustasy, tectonism, and clastic sediment supply were responsible for the observed cycles. Lithofacies analysis indicates that location within the foreland basin played a significant role in cycle attributes. In the deeper portions of the basin (e.g., Dalton Bluff), an idealized cycle, from base to top consists of (1) shale/marl facies, (2) brachiopod wackestone facies, (3) phylloid algal facies, and (4) marine clastic facies. No evidence for subaerial exposure of cycle caps is noted. In contrast, in shallow portions of the basin near the forebulge (e.g., Johnson Mesa) the marine clastic facies is substituted by crinoidal grainstone/packstone facies that is capped by subaerial exposure surface. Each of the two cycles displays an overall grand (lower order) shallowing-upward cycle. This grand cycle developed as sediments infilled the initially starved foreland basin.

  3. Classification Scheme for Diverse Sedimentary and Igneous Rocks Encountered by MSL in Gale Crater

    NASA Technical Reports Server (NTRS)

    Schmidt, M. E.; Mangold, N.; Fisk, M.; Forni, O.; McLennan, S.; Ming, D. W.; Sumner, D.; Sautter, V.; Williams, A. J.; Gellert, R.

    2015-01-01

    The Curiosity Rover landed in a lithologically and geochemically diverse region of Mars. We present a recommended rock classification framework based on terrestrial schemes, and adapted for the imaging and analytical capabilities of MSL as well as for rock types distinctive to Mars (e.g., high Fe sediments). After interpreting rock origin from textures, i.e., sedimentary (clastic, bedded), igneous (porphyritic, glassy), or unknown, the overall classification procedure (Fig 1) involves: (1) the characterization of rock type according to grain size and texture; (2) the assignment of geochemical modifiers according to Figs 3 and 4; and if applicable, in depth study of (3) mineralogy and (4) geologic/stratigraphic context. Sedimentary rock types are assigned by measuring grains in the best available resolution image (Table 1) and classifying according to the coarsest resolvable grains as conglomerate/breccia, (coarse, medium, or fine) sandstone, silt-stone, or mudstone. If grains are not resolvable in MAHLI images, grains in the rock are assumed to be silt sized or smaller than surface dust particles. Rocks with low color contrast contrast between grains (e.g., Dismal Lakes, sol 304) are classified according to minimum size of apparent grains from surface roughness or shadows outlining apparent grains. Igneous rocks are described as intrusive or extrusive depending on crystal size and fabric. Igneous textures may be described as granular, porphyritic, phaneritic, aphyric, or glassy depending on crystal size. Further descriptors may include terms such as vesicular or cumulate textures.

  4. Rollerjaw Rock Crusher

    NASA Technical Reports Server (NTRS)

    Peters, Gregory; Brown, Kyle; Fuerstenau, Stephen

    2009-01-01

    The rollerjaw rock crusher melds the concepts of jaw crushing and roll crushing long employed in the mining and rock-crushing industries. Rollerjaw rock crushers have been proposed for inclusion in geological exploration missions on Mars, where they would be used to pulverize rock samples into powders in the tens of micrometer particle size range required for analysis by scientific instruments.

  5. Accelerated Weathering of Rocks.

    DTIC Science & Technology

    1977-08-01

    Dry tests en polished specimens with alternating heating and co- oling actions; ii) Wet tests in destilled water, with alternating...Rock-type Dry tests KxlO2 Wet tests KxlO2 Sound rock SR 3.64 8.31 Medium altered rock MAR 4.96 31.58 Very altered rock VAR 8.89 116.20 TABLE X...Sound rock SR Medium altered rock Very altered rock" KAR VAR ’ Reflectivity R (%) dry test wet test dry test wet test dry test wet

  6. Petrogenesis of lunar rocks: Rb-Sr constraints and lack of H2O

    NASA Technical Reports Server (NTRS)

    Albee, A. L.; Gancarz, A. J.

    1974-01-01

    Rb and Sr isotopic data and other chemical data indicate major lunar differentiation at about 4.6 AE and very limited subsequent differentiation. The constraints of limited differentiation post 4.6 AE and the apparent lack of H2O on the moon, when applied to the derivation and petrogenesis of lunar samples, suggest the following: (1) soil samples, breccias, metaclastic rocks, and feldspathic basalts represent mixtures of repeatedly-modified clastic material, which was ultimately derived from materials formed during the about 4.6 AE differentiation; and (2) mare basalts crystallized from melts which formed by partial melting and, which developed without equilibration between the melt and crystalline residuum.

  7. Transport of marked pebbles in short periods of time on a coarse clastic beach (Marina di Pisa, Italy)

    NASA Astrophysics Data System (ADS)

    Bertoni, D.; Ciavola, P.; Grottoli, E.; Sarti, G.

    2012-04-01

    Transport of coarse sediments on coarse clastic beaches still presents aspects that are not fully understood. For instance, there is a generally perceived notion that during fair-weather periods coarse grains hardly move, if not at all. The aim of this experiment is to prove that sediments such as pebbles are subject to significant shift in very short lapses of time and under low energy waves. An artificial coarse clastic beach at Marina di Pisa (Tuscany, Italy) was chosen as study site: Barbarossa beach is 110 m long and is bounded by two groynes. The mean grain size is about 40-to-50 mm. About 80 pebbles were marked by means of the RFID technology, which enables to univocally identify the tracers. The marked pebbles were released along cross-shore transects (one pebble each on the fair-weather berm, on the beachface and on the step crest) on the morning of September 15th, and two recovery campaigns were carried out after 6 and 24 hours from the injection. No particular wave activity was recorded during the time frame of the experiment. After the first recovery campaign, which was performed 6 hours later than the injection, about 94% of the pebbles were detected. After the second recovery campaign, 24 hours later, the recovery rate decreased to 89%. Considering that the technique provides for detection of tracers within 50 cm, the resulting loss of pebbles after so brief spans of time is remarkable. The lack of detection of few tracers implies that the transport rate that they experienced is not negligible. The highest rate of losses was recorded on the beachface, the zone that is subjected the most to waves even under calm conditions. Pebble movement is also confirmed by the fact that tracers detected after the first recovery campaign were not detected once again after the second recovery campaign, and vice versa. The results of the experiment are useful to better define the transport of coarse sediments, verifying that pebbles have to be expected be moving even

  8. Sedimentation and basin-fill history of the Neogene clastic succession exposed in the southeastern fold belt of the Bengal Basin, Bangladesh: a high-resolution sequence stratigraphic approach

    NASA Astrophysics Data System (ADS)

    Royhan Gani, M.; Mustafa Alam, M.

    2003-02-01

    The Tertiary basin-fill history of the Bengal Basin suffers from oversimplification. The interpretation of the sedimentary history of the basin should be consistent with the evolution of its three geo-tectonic provinces, namely, western, northeastern and eastern. Each province has its own basin generation and sediment-fill history related mainly to the Indo-Burmese and subordinately to the Indo-Tibetan plate convergence. This paper is mainly concerned with facies and facies sequence analysis of the Neogene clastic succession within the subduction-related active margin setting (oblique convergence) in the southeastern fold belt of the Bengal Basin. Detailed fieldwork was carried out in the Sitapahar anticline of the Rangamati area and the Mirinja anticline of the Lama area. The study shows that the exposed Neogene succession represents an overall basinward progradation from deep marine through shallow marine to continental-fluvial environments. Based on regionally correlatable erosion surfaces the entire succession (3000+ m thick) has been grouped into three composite sequences C, B and A, from oldest to youngest. Composite sequence C begins with deep-water base-of-slope clastics overlain by thick slope mud that passes upward into shallow marine and nearshore clastics. Composite sequence B characteristically depicts tide-dominated open-marine to coastal depositional systems with evidence of cyclic marine regression and transgression. Repetitive occurrence of incised channel, tidal inlet, tidal ridge/shoal, tidal flat and other tidal deposits is separated by shelfal mudstone. Most of the sandbodies contain a full spectrum of tide-generated structures (e.g. herringbone cross-bedding, bundle structure, mud couplet, bipolar cross-lamination with reactivation surfaces, 'tidal' bedding). Storm activities appear to have played a subordinate role in the mid and inner shelf region. Rizocorallium, Rosselia, Planolites and Zoophycos are the dominant ichnofacies within the

  9. Molecular orbital calculations of proton transfer involving amines as models for the clastic binding of opiates with their receptor

    SciTech Connect

    Bennett, L.K.; Beamer, R.L.

    1986-08-01

    Semi-empirical (CNDO) molecular orbital calculations, based on a previously reported ammonia-amine model system, were performed on an extended series of methyl-, ethyl-, and propylamines as models for the analgesic receptor. Methyl-, dimethyl-, and trimethylamines were chosen to represent the opiate molecules. Interatomic distances were varied within normally expected biological values. The results for the larger systems are similar to more elaborate calculations previously reported using smaller molecules. At internuclear distances of greater than 0.275 nm, the potential energy curves had two minima. At 0.2731 nm, the optimized N-N distance, the depth of the minima in the potential energy curve were not as great. Energy differences as well as population differences suggest deviation from the currently stated clastic binding theories mechanism for the analgesic response of the tertiary amines. The dimethylamine energy profile and population data indicate that the hypothesis of N-demethylated opiate as the active molecule needs further consideration and investigation. Investigation of larger systems is also indicated to develop increasingly realistic models for the analgesic response.

  10. Sedimentological and palaeoenvironmental studies on the clastic sequence of Gebel El-Zeit area, gulf of Suez, Egypt

    NASA Astrophysics Data System (ADS)

    Abdel-Wahab, Antar; Allam, A.; Kholief, M.; Salem, A.

    1992-01-01

    The present work deals with the sedimentological and palaeoenvironmental studies of the Palaeozoic clastic sequence (Cambrian?) of the Gebel El-Zeit area. The sandstones which build up the major part of this sequence are fine to coarse grained moderately to well sorted, mostly of unimodal patterns, strongly fine skewed to near symmetrical and vary from meso- to very lepto-kurtic. The grain-size parameters and their bivariate relations do not give an exact environment of deposition nevertheless, most of them have a fluviatile origin. So, the application of some of the bivariate relations to ancient sediments, which microscopically show mild or no cementation, is still valid if coupled with other parameters, such as sedimentary structures, palaeocurrent analysis and other confirmed data. The palaeocurrent analysis indicates that these sandstones came from two completely different sources. A marine transgression from the north northeast produced the Araba Formation, whereas the Naqus Formation has been interpreted as fluvial. The source is situated to the south southwest. The streams were probably very erratic and intermittent.

  11. Crestal unconformities as indicators of clastic stratigraphic traps: genetic relation of Berlin field and Elk City structure, deep Anadarko basin

    SciTech Connect

    Lyday, J.R.

    1988-02-01

    The Berlin fan-delta gas reservoir in the deep Anardarko basin was deposited during the late Atokan (Pennsylvanian) as a response to the initial uplift and erosion of the Elk City structure. During the late Atokan pulse of the episodic Pennsylvanian orogeny in the south-central US, abrupt epeirogenic uplift and brittle deformation created an interregional unconformity on positive areas around foreland and cratonic basins. The Elk City structure within the deep Anadarko basin originated as a distinct, subaerially exposed upthrust-block during the late Atokan tectonic event. A crestal unconformity developed on the emergent upthrust block concurrent with its uplift. Terrigenous, detrital Atoka dolomite, originally sourced from the Arbuckle dolomite (Cambrian-Ordovician) of the Amarillo-Wichita uplift, was eroded from the upthrust block and recycled northward as the Berlin fan-delta. Today, the Berlin recrystallized, recycled detrital dolomite fan-delta is a large 41 mi/sup 2/ overpressured gas reservoir with 242-362 bcf reserves at 15,000 ft. The Berlin field is genetically related to the late Atokan crestal unconformity of the Elk City structure, and is an example of the association of crestal unconformities and clastic stratigraphic traps. Such stratigraphic traps originated in marine environments proximal to active structures that have become subaerially exposed. With adequate seals and favorable structural position, detrital deposits recycled from local uplifts can form significant stratigraphic traps. Such stratigraphic traps can occur in compressional, extensional, and diapiric regions.

  12. 3-D seismic evidence of the effects of carbonate karst collapse on overlying clastic stratigraphy and reservoir compartmentalization

    SciTech Connect

    Hardage, B.A.; Carr, D.L.; Simmons, J.L. Jr.; Jons, R.A.; Lancaster, D.E.; Elphick, R.Y.; Pendleton, V.M.

    1996-09-01

    A multidisciplinary team, composed of stratigraphers, petrophysicists, reservoir engineers, and geophysicists, studied a portion of Boonsville gas field in the Fort Worth Basin of north-central Texas to determine how modern techniques can be combined to understand the mechanisms by which fluvio-deltaic depositional processes create reservoir compartmentalization in a low- to moderate-accommodation basin. An extensive database involving well logs, cores, production, and pressure data from more than 200 wells, 26 mi{sup 2} of 3-D seismic data, vertical seismic profiles, and checkshots was assembled to support this investigation. The authors found the most important geologic influence on stratigraphy and reservoir compartmentalization in this basin to be the existence of numerous karst collapse chimneys over the area covered. These near-vertical karst collapses originated in, or near, the deep Ordovician-age Ellenburger carbonate section and created vertical chimneys extending as high as 2,500 ft above their point of origin, causing significant disruptions in the overlying clastic strata.

  13. Classification scheme for sedimentary and igneous rocks in Gale crater, Mars

    NASA Astrophysics Data System (ADS)

    Mangold, N.; Schmidt, M. E.; Fisk, M. R.; Forni, O.; McLennan, S. M.; Ming, D. W.; Sautter, V.; Sumner, D.; Williams, A. J.; Clegg, S. M.; Cousin, A.; Gasnault, O.; Gellert, R.; Grotzinger, J. P.; Wiens, R. C.

    2017-03-01

    Rocks analyzed by the Curiosity rover in Gale crater include a variety of clastic sedimentary rocks and igneous float rocks transported by fluvial and impact processes. To facilitate the discussion of the range of lithologies, we present in this article a petrological classification framework adapting terrestrial classification schemes to Mars compositions (such as Fe abundances typically higher than for comparable lithologies on Earth), to specific Curiosity observations (such as common alkali-rich rocks), and to the capabilities of the rover instruments. Mineralogy was acquired only locally for a few drilled rocks, and so it does not suffice as a systematic classification tool, in contrast to classical terrestrial rock classification. The core of this classification involves (1) the characterization of rock texture as sedimentary, igneous or undefined according to grain/crystal sizes and shapes using imaging from the ChemCam Remote Micro-Imager (RMI), Mars Hand Lens Imager (MAHLI) and Mastcam instruments, and (2) the assignment of geochemical modifiers based on the abundances of Fe, Si, alkali, and S determined by the Alpha Particle X-ray Spectrometer (APXS) and ChemCam instruments. The aims are to help understand Gale crater geology by highlighting the various categories of rocks analyzed by the rover. Several implications are proposed from the cross-comparisons of rocks of various texture and composition, for instance between in place outcrops and float rocks. All outcrops analyzed by the rover are sedimentary; no igneous outcrops have been observed. However, some igneous rocks are clasts in conglomerates, suggesting that part of them are derived from the crater rim. The compositions of in-place sedimentary rocks contrast significantly with the compositions of igneous float rocks. While some of the differences between sedimentary rocks and igneous floats may be related to physical sorting and diagenesis of the sediments, some of the sedimentary rocks (e

  14. Geotechnical Descriptions of Rock and Rock Masses.

    DTIC Science & Technology

    1985-04-01

    user of the field log can relate to the general class of rock being described. For example, the rock name " syenite " might be qualified by adding "the...FELDSPAR PRE-S---- Coarne Texture Granite Syenite Qts ononite Honzonite Cabbro Peridotite (Platonic or to Qtx Diorite to Diorite Pyroxenite intrusive

  15. Rocks in Our Pockets

    ERIC Educational Resources Information Center

    Plummer, Donna; Kuhlman, Wilma

    2005-01-01

    To introduce students to rocks and their characteristics, teacher can begin rock units with the activities described in this article. Students need the ability to make simple observations using their senses and simple tools.

  16. Rocks and Minerals.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Provides background information on rocks and minerals, including the unique characteristics of each. Teaching activities on rock-hunting and identification, mineral configurations, mystery minerals, and growing crystals are provided. Reproducible worksheets are included for two of the activities. (TW)

  17. Theory of wing rock

    NASA Technical Reports Server (NTRS)

    Hsu, C.-H.; Lan, C. E.

    1985-01-01

    Wing rock is one type of lateral-directional instabilities at high angles of attack. To predict wing rock characteristics and to design airplanes to avoid wing rock, parameters affecting wing rock characteristics must be known. A new nonlinear aerodynamic model is developed to investigate the main aerodynamic nonlinearities causing wing rock. In the present theory, the Beecham-Titchener asymptotic method is used to derive expressions for the limit-cycle amplitude and frequency of wing rock from nonlinear flight dynamics equations. The resulting expressions are capable of explaining the existence of wing rock for all types of aircraft. Wing rock is developed by negative or weakly positive roll damping, and sustained by nonlinear aerodynamic roll damping. Good agreement between theoretical and experimental results is obtained.

  18. The Rock Cycle

    ERIC Educational Resources Information Center

    Singh, Raman J.; Bushee, Jonathan

    1977-01-01

    Presents a rock cycle diagram suitable for use at the secondary or introductory college levels which separates rocks formed on and below the surface, includes organic materials, and separates products from processes. (SL)

  19. Principles of rock deformation

    SciTech Connect

    Nicolas, A.

    1987-01-01

    This text focuses on the recent achievements in the analysis of rock deformation. It gives an analytical presentation of the essential structures in terms of kinetic and dynamic interpretation. The physical properties underlying the interpretation of rock structures are exposed in simple terms. Emphasized in the book are: the role of fluids in rock fracturing; the kinematic analysis of magnetic flow structures; the application of crystalline plasticity to the kinematic and dynamic analysis of the large deformation imprinted in many metamorphic rocks.

  20. Grain-size distribution of volcaniclastic rocks 2: Characterizing grain size and hydraulic sorting

    NASA Astrophysics Data System (ADS)

    Jutzeler, Martin; McPhie, Jocelyn; Allen, Sharon R.; Proussevitch, A. A.

    2015-08-01

    Quantification of the grain size distribution of sediments allows interpretation of processes of transport and deposition. Jutzeler et al. (2012) developed a technique to determine grain size distribution of consolidated clastic rocks using functional stereology, allowing direct comparison between unconsolidated sediments and rocks. Here, we develop this technique to characterize hydraulic sorting and infer transport and deposition processes. We compare computed grain size and sorting of volcaniclastic rocks with field-based characteristics of volcaniclastic facies for which transport and depositional mechanisms have been inferred. We studied pumice-rich, subaqueous facies of volcaniclastic rocks from the Oligocene Ohanapecosh Formation (Ancestral Cascades, Washington, USA), Pliocene Dogashima Formation (Izu Peninsula, Honshu, Japan), Miocene Manukau Subgroup (Northland, New Zealand) and the Quaternary Sierra La Primavera caldera (Jalisco State, Mexico). These sequences differ in bed thickness, grading and abundance of matrix. We propose to evaluate grain size and sorting of volcaniclastic deposits by values of their modes, matrix proportion (< 2 mm; F-1) and D16, instead of median diameter (D50) and standard deviation parameters. F-1 and D16 can be uniformly used to characterize and compare sieving and functional stereology data. Volcaniclastic deposits typically consist of mixtures of particles that vary greatly in density and porosity. Hydraulic sorting ratios can be used to test whether mixed clast populations of pumice and dense clasts are hydraulically sorted with each other, considering various types of transport underwater. Evaluation of this ratio for our samples shows that most studied volcaniclastic facies are deposited by settling from density currents, and that basal dense clast breccias are emplaced by shear rolling. These hydraulic sorting ratios can be applied to any type of clastic rocks, and indifferently on consolidated and unconsolidated samples.

  1. 68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: STRESS SHEET, SHEET 4; MAY, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  2. My Pet Rock

    ERIC Educational Resources Information Center

    Lark, Adam; Kramp, Robyne; Nurnberger-Haag, Julie

    2008-01-01

    Many teachers and students have experienced the classic pet rock experiment in conjunction with a geology unit. A teacher has students bring in a "pet" rock found outside of school, and the students run geologic tests on the rock. The tests include determining relative hardness using Mohs scale, checking for magnetization, and assessing luster.…

  3. Geology, mineralogy, and chemistry of sediment-hosted clastic massive sulfides in shallow cores, Middle Valley, northern Juan de Fuca Ridge

    SciTech Connect

    Goodfellow, W.D.; Franklin, J.M. )

    1993-12-01

    Middle Valley is a sediment-covered rift near the northern end of Juan de Fuca Ridge. Hydrothermal fluids are presently being discharged at two vent fields about 3 km apart, Bent Hill and the area of active venting. The hydrothermally active chimneys at both Bent Hill and the area of active venting consist of anhydrite and Mg-rich silicates with minor pyrite, Cu-Fe sulfide, sphalerite, and galena. Hydrothermal discharge in these areas appears to be focused along extensional faults. At the Bent Hill massive sulfide deposit, clastic sulfide layers are interbedded with hydrothermally altered and unaltered hemipelagic and turbiditic sediment along the flanks of the sulfide mound. Sulfide textures and mineralogy suggest that the Bent Hill sulfide mound formed by the build-up and collapse of sulfide chimneys, the resedimentation of sulfide debris and the formation of clastic sulfide layers, and the infilling and replacement of clastic sulfides by hydrothermal fluids near vents. Sulfur isotope values that are consistently more positive than basaltic sulfur support the addition of seawater sulfur. Pb isotope values for the Bent Hill deposit that are transitional between midocean ridge basalt (MORB) and Middle Valley sediments indicate that the sulfides probably formed from fluids which originated in the oceanic crust but which have been modified by reaction with lower temperature (<274 C) fluids generated in the sedimentary pile, similar to those now venting in Middle Valley.

  4. ADVANCED OIL RECOVERY TECHNOLOGIES FOR IMPROVED RECOVERY FROM SLOPE BASIN CLASTIC RESERVOIRS, NASH DRAW BRUSHY CANYON POOL, EDDY COUNTY, NM

    SciTech Connect

    Mark B. Murphy

    2001-10-31

    The Nash Draw Brushy Canyon Pool (NDP) in southeast New Mexico is one of the nine projects selected in 1995 by the U.S. Department of Energy (DOE) for participation in the Class III Reservoir Field Demonstration Program. The goals of the DOE cost-shared Class Program are to: (1) extend economic production, (2) increase ultimate recovery, and (3) broaden information exchange and technology application. Reservoirs in the Class III Program are focused on slope basin and deep-basin clastic depositional types. Production at the NDP is from the Brushy Canyon formation, a low-permeability turbidite reservoir in the Delaware Mountain Group of Permian, Guadalupian age. A major challenge in this marginal-quality reservoir is to distinguish oil-productive pay intervals from water-saturated non-pay intervals. Because initial reservoir pressure is only slightly above bubble-point pressure, rapid oil decline rates and high gas/oil ratios are typically observed in the first year of primary production. Limited surface access, caused by the proximity of underground potash mining and surface playa lakes, prohibits development with conventional drilling. Reservoir characterization results obtained to date at the NDP show that a proposed pilot injection area appears to be compartmentalized. Because reservoir discontinuities will reduce effectiveness of a pressure maintenance project, the pilot area will be reconsidered in a more continuous part of the reservoir if such areas have sufficient reservoir pressure. Most importantly, the advanced characterization results are being used to design extended reach/horizontal wells to tap into predicted ''sweet spots'' that are inaccessible with conventional vertical wells. The activity at the NDP during the past year has included the completion of the NDP Well No.36 deviated/horizontal well and the completion of additional zones in three wells, the design of the NDP No.33 directional/horizontal well, The planning and regulatory approval for the

  5. Tectonic framework of petroliferous rocks in Alaska: hydrocarbons

    USGS Publications Warehouse

    Grantz, Arthur; Kirschner, C.E.

    1976-01-01

    Alaska, which contains about 28% of the land and continental shelf of the United States, is estimated by the U.S. Geological Survey to contain about one third of the nation's undiscovered oil and about one sixth of its undiscovered natural gas. The Survey estimates that fields discovered in Alaska through 1972 ultimately may produce about 26 billion bbl of oil and 68 Tcf of natural gas. In northern Alaska, Paleozoic and Mesozoic shelf and slope carbonate and clastic rocks of the Brooks Range orogen were thrust relatively northward over the depressed south margin of the Paleozoic and Mesozoic Arctic platform. A foredeep, the Colville geosyncline, developed across the depressed margin of the platform in earliest Cretaceous time. Detritus from the Brooks Range filled the foredeep and prograded northward to fill the Cretaceous and Tertiary North Chukchi and Umiat-Camden basins and form the progradational Beaufort shelf. The largest petroleum reserves (Prudhoe Bay and associated fields) and the best prospects for additional large discoveries in Alaska lie in the areally extensive upper Paleozoic to Tertiary carbonate and clastic rocks of northern Alaska. In southern Alaska, a series of arc-trench systems developed on oceanic rocks during Jurassic and Cretaceous time. Between these arcs and the metamorphic (continental) terranes of east-central and northern Alaska, large back-arc and arc-trench gap basins received thick volcanic and detrital deposits. These deposits were extensively, and commonly intensely, deformed and disrupted by mid-Jurassic to Tertiary plutonism, Laramide oroclinal bending, wrench faulting, and arc-related compression. This deformation, coupled with low porosity (in part produced by diagenetic mobilization of labile constituents), has left these rocks with only modest, local prospects for petroleum. Laramide events compressed and consolidated ("continentalized") the late Mesozoic back-arc basin deposits and welded them to the older continental

  6. Alteration of immature sedimentary rocks on Earth and Mars. Recording Aqueous and Surface-atmosphere Processes

    SciTech Connect

    Cannon, Kenneth M.; Mustard, John F.; Salvatore, Mark R.

    2015-03-05

    The rock alteration and rind formation in analog environments like Antarctica may provide clues to rock alteration and therefore paleoclimates on Mars. Clastic sedimentary rocks derived from basaltic sources have been studied in situ by martian rovers and are likely abundant on the surface of Mars. Moreover, how such rock types undergo alteration when exposed to different environmental conditions is poorly understood compared with alteration of intact basaltic flows. Here we characterize alteration in the chemically immature Carapace Sandstone from Antarctica, a terrestrial analog for martian sedimentary rocks. We employ a variety of measurements similar to those used on previous and current Mars missions. Laboratory techniques included bulk chemistry, powder X-ray diffraction (XRD), hyperspectral imaging and X-ray absorption spectroscopy. Through these methods we find that primary basaltic material in the Carapace Sandstone is pervasively altered to hydrated clay minerals and palagonite as a result of water–rock interaction. A thick orange rind is forming in current Antarctic conditions, superimposing this previous aqueous alteration signature. The rind exhibits a higher reflectance at visible-near infrared wavelengths than the rock interior, with an enhanced ferric absorption edge likely due to an increase in Fe3+ of existing phases or the formation of minor iron (oxy)hydroxides. This alteration sequence in the Carapace Sandstone results from decreased water–rock interaction over time, and weathering in a cold, dry environment, mimicking a similar transition early in martian history. This transition may be recorded in sedimentary rocks on Mars through a similar superimposition mechanism, capturing past climate changes at the hand sample scale. These results also suggest that basalt-derived sediments could have sourced significant volumes of hydrated minerals on early Mars due to their greater permeability compared with intact igneous rocks.

  7. Alteration of immature sedimentary rocks on Earth and Mars: Recording aqueous and surface-atmosphere processes

    NASA Astrophysics Data System (ADS)

    Cannon, Kevin M.; Mustard, John F.; Salvatore, Mark R.

    2015-05-01

    Rock alteration and rind formation in analog environments like Antarctica may provide clues to rock alteration and therefore paleoclimates on Mars. Clastic sedimentary rocks derived from basaltic sources have been studied in situ by martian rovers and are likely abundant on the surface of Mars. However, how such rock types undergo alteration when exposed to different environmental conditions is poorly understood compared with alteration of intact basaltic flows. Here we characterize alteration in the chemically immature Carapace Sandstone from Antarctica, a terrestrial analog for martian sedimentary rocks. We employ a variety of measurements similar to those used on previous and current Mars missions. Laboratory techniques included bulk chemistry, powder X-ray diffraction (XRD), hyperspectral imaging and X-ray absorption spectroscopy. Through these methods we find that primary basaltic material in the Carapace Sandstone is pervasively altered to hydrated clay minerals and palagonite as a result of water-rock interaction. A thick orange rind is forming in current Antarctic conditions, superimposing this previous aqueous alteration signature. The rind exhibits a higher reflectance at visible-near infrared wavelengths than the rock interior, with an enhanced ferric absorption edge likely due to an increase in Fe3+ of existing phases or the formation of minor iron (oxy)hydroxides. This alteration sequence in the Carapace Sandstone results from decreased water-rock interaction over time, and weathering in a cold, dry environment, mimicking a similar transition early in martian history. This transition may be recorded in sedimentary rocks on Mars through a similar superimposition mechanism, capturing past climate changes at the hand sample scale. Our results also suggest that basalt-derived sediments could have sourced significant volumes of hydrated minerals on early Mars due to their greater permeability compared with intact igneous rocks.

  8. Pressure-velocity relations in reservoir rocks: Modified MacBeth's equation

    NASA Astrophysics Data System (ADS)

    Grana, Dario

    2016-09-01

    The knowledge of the saturation and pressure effects on elastic properties is a key factor in reservoir monitoring. The relation between saturation changes and velocity variations is well known in rock physics and at seismic frequency it can be satisfactorily described by Gassmann's equations. The pressure effect still requires deeper investigations in order to be included in rock physics models for 4D studies. Theoretical models of velocity-pressure relations often do not match lab measurements, or contain empirical constants or theoretical parameters that are difficult to calibrate or do not have a precise physical meaning. In this work, I present a new model to describe the pressure sensitivity of elastic moduli for clastic rocks. The proposed model is an extension of MacBeth's relations. These equations are then integrated within a complete rock physics model to describe the relation between rock properties (porosity and clay content), dynamic attributes (saturation and pressure) and elastic properties. The proposed model is calibrated with laboratory measurements of dry samples over a wide range of pressure variations and then applied to well data to simulate different production scenarios. The complete rock physics model can then be used in time-lapse inversion to predict the distribution of dynamic property changes in the reservoir within an inversion workflow for reservoir monitoring.

  9. The potassic sedimentary rocks in Gale Crater, Mars, as seen by ChemCam Onboard Curiosity

    USGS Publications Warehouse

    Le Deit, Laetitia; Mangold, Nicolas; Forni, Olivier; Cousin, Agnes; Lasue, Jeremie; Schröder, Susanne; Wiens, Roger C.; Sumner, Dawn Y.; Fabre, Cecile; Stack, Katherine M.; Anderson, Ryan; Blaney, Diana L.; Clegg, Samuel M.; Dromart, Gilles; Fisk, Martin; Gasnault, Olivier; Grotzinger, John P.; Gupta, Sanjeev; Lanza, Nina; Le Mouélic, Stephane; Maurice, Sylvestre; McLennan, Scott M.; Meslin, Pierre-Yves; Nachon, Marion; Newsom, Horton E.; Payre, Valerie; Rapin, William; Rice, Melissa; Sautter, Violaine; Treiman, Alan H.

    2016-01-01

    The Mars Science Laboratory rover Curiosity encountered potassium-rich clastic sedimentary rocks at two sites in Gale Crater, the waypoints Cooperstown and Kimberley. These rocks include several distinct meters thick sedimentary outcrops ranging from fine sandstone to conglomerate, interpreted to record an ancient fluvial or fluvio-deltaic depositional system. From ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) chemical analyses, this suite of sedimentary rocks has an overall mean K2O abundance that is more than 5 times higher than that of the average Martian crust. The combined analysis of ChemCam data with stratigraphic and geographic locations reveals that the mean K2O abundance increases upward through the stratigraphic section. Chemical analyses across each unit can be represented as mixtures of several distinct chemical components, i.e., mineral phases, including K-bearing minerals, mafic silicates, Fe-oxides, and Fe-hydroxide/oxyhydroxides. Possible K-bearing minerals include alkali feldspar (including anorthoclase and sanidine) and K-bearing phyllosilicate such as illite. Mixtures of different source rocks, including a potassium-rich rock located on the rim and walls of Gale Crater, are the likely origin of observed chemical variations within each unit. Physical sorting may have also played a role in the enrichment in K in the Kimberley formation. The occurrence of these potassic sedimentary rocks provides additional evidence for the chemical diversity of the crust exposed at Gale Crater.

  10. Chemical, multispectral, and textural constraints on the composition and origin of rocks at the Mars Pathfinder landing site

    USGS Publications Warehouse

    McSween, H.Y.; Murchie, S.L.; Crisp, J.A.; Bridges, N.T.; Anderson, R.C.; Bell, J.F.; Britt, D.T.; Brückner, J.; Dreibus, G.; Economou, T.; Ghosh, A.; Golombek, M.P.; Greenwood, J.P.; Johnson, J. R.; Moore, H.J.; Morris, R.V.; Parker, T.J.; Rieder, R.; Singer, R.; Wänke, H.

    1999-01-01

    Rocks at the Mars Pathfinder site are probably locally derived. Textures on rock surfaces may indicate volcanic, sedimentary, or impact-generated rocks, but aeolian abration and dust coatings prevent unambiguous interpretation. Multispectral imaging has resolved four spectral classes of rocks: gray and red, which occur on different surfaces of the same rocks; pink, which is probably soil crusts; and maroon, which occurs as large boulders, mostly in the far field. Rocks are assigned to two spectral trends based on the position of peak reflectance: the primary spectral trend contains gray, red, and pink rocks; maroon rocks constitute the secondary spectral trend. The spatial pattern of spectral variations observed is oriented along the prevailing wind direction. The primary spectral trend arises from thin ferric coatings of aeolian dust on darker rocks. The secondary spectral trend is apparently due to coating by a different mineral, probably maghemite or ferrihydrite. A chronology based on rock spectra suggests that rounded maroon boulders constitute the oldest petrologic unit (a flood deposit), succeeded by smaller cobbles possibly deposited by impact, and followed by aeolian erosion and deposition. Nearly linear chemical trends in alpha proton X-ray spectrometer rock compositions are interpreted as mixing lines between rock and adhering dust, a conclusion supported by a correlation between sulfur abundance and red/blue spectral ratio. Extrapolations of regression lines to zero sulfur give the composition of a presumed igneous rock. The chemistry and normative mineralogy of the sulfur-free rock resemble common terrestrial volcanic rocks, and its classification corresponds to andesite. Igneous rocks of this composition may occur with clastic sedimentary rocks or impact melts and breccias. However, the spectral mottling expected on conglomerates or breccias is not observed in any APXS-analyzed rocks. Interpretation of the rocks as andesites is complicated by absence

  11. Origin and significance of tourmaline-rich rocks in the Broken Hill district, Australia

    USGS Publications Warehouse

    Slack, J.F.; Palmer, M.R.; Stevens, B.P.J.; Barnes, R.G.

    1993-01-01

    Tourmaline-rich rocks are widespread minor lithologies within the Early Proterozoic Willyama supergroup. Most of the tourmaline-rich rocks are within the Broken Hill Group that hosts the main Pb-Zn-Ag ores. Electron microprobe analyses of tourmalines intergrown with Fe sulfides at the Globe mine show Mg-rich compositions relative to tourmalines in sulfide-free assemblages from the same area, suggesting early (premetamorphic) introduction of boron and Mg enrichment of tourmaline by sulfide-silicate reactions during metamorphism. Combined field and geochemical data indicate that the district tourmalinites represent normal clastic sediments that were metasomatically altered by boron-rich hydrothermal fluids at or below the sediment-water interface. The geochemical data imply relative immobility of Al, Ti, Cr, and heavy REE during hydrothermal alteration and later metamorphism. -from Authors

  12. Joint Geophysical and Hydrologic Constraints on Shallow Groundwater Flow Systems in Clastic Salt Marshes of the South Atlantic Bight

    NASA Astrophysics Data System (ADS)

    Ruppel, C.; Fulton, P.; Schultz, G. M.; Castillo, L.; Bartlett, J.; Sibley, S.

    2005-12-01

    Salt marsh systems play a critical role in buffering upland coastal areas from the influence of open saltwater bodies and in filtering contaminants that originate offshore or are flushed from uplands. For these reasons, it is important to understand the salt marsh hydrologic cycle, especially the interaction of groundwater and surface water across low-lying coastal fringes and the changes in physical, chemical, and ecological parameters across salinity gradients extending from upland to tidal creek to open water. For the past 5 years, we have conducted hydrogeophysical surveys (inductive EM and DC resistivity) and collected limited, coincident groundwater hydrologic data in clastic salt marshes throughout the South Atlantic Bight (SAB), stretching from South Carolina on the north to the Georgia-Florida border on the south. All of the marshes are dominated by Spartina and Juncus grasses and are cut by tidally-influenced creeks, but both the lithology and age of the marshes vary widely. For example, one highly homogeneous marsh study site has formed only within the past century, while most sites have existed for thousands of years and have laterally and vertically heterogeneous lithology. Geophysical images of the marsh subsurface and coincident monitoring of groundwater temperature, water level, and/or chemistry consistently show that marshes in the mixed energy environment of the middle part of the SAB (GCE LTER) tend to be dominated by submarsh discharge of freshwater to adjacent tidal creeks. In the South Carolina part of the SAB, we have greater evidence for seepage, particularly through biologically-created macropore networks and permeable sediment bodies that intersect tidal creeks. It is possible though that the South Carolina results are not so much 'universal' as reflective of local lithology. In a very young marsh near the Florida border, geophysical imaging implies a mixture of seepage and submarsh flow, and hydrologic data provide unequivocal proof that

  13. Periglacial complexes in Utopia Planitia: rimless, tiered depressions, (clastically) sorted and unsorted polygonised terrain and an ice-rich mantle

    NASA Astrophysics Data System (ADS)

    Soare, Richard; Conway, Susan; Gallagher, Colman; Dohm, James; Clifford, Stephen M.; Williams, Jean-pierre

    2016-10-01

    We report the spatial and possible genetic-relationship at the mid-latitudes of Utopia Planitia (45-500N 115-1200E), Mars, of: (a) metre to decametre deep, rimless, tiered depressions; terrain that exhibits (b) (clastically) sorted and (c) unsorted (small-sized) polygons; and, (d) a very youthful, ice-rich mantle. We show that these individual landscape features are separated stratigraphically, this being presented to the Mars community for the first time, and suggest that the stratigraphical separation of these features could be the result of boundary conditions and formation processes that have varied much more widely than has been thought hitherto. In cold-climate and non-glacial regions such as the Yamal Peninsula of eastern Russia and the Tuktoyaktuk Coastlands of northern Canada, landscape assemblages comprised of similar features are referenced as "ice complexes" and are indicative of periglacialism on two fronts: first, the presence of "ice-rich" permafrost or permafrost comprised of "excess ice", i.e. "permafrost" whose pore space is exceeded by the "water ice" within that body of sediment; and, second, antecedently or currently active freeze-thaw cycling, minimally, to the full depth of the "ice-complex" depressions. In the Dry Valleys of the Antarctic, where the atmospheric aridity and cold-temperatures approach those of Mars, ice-vapour diffusion and adsorption cycles are cited as the means by which the near-surface, permafrost, i.e. ≤1m deep, has become ice-cemented. However, the metre to decametre depths of the "ice-complex" depressions on Earth and the morphologically-similar ones on Mars lie beyond the vertical reach of the Antarctic diffusion and adsorption cycles, both empirically and theoretically. By deduction, this points to the freeze-thaw cycling of water to depth, fostered either by exogenic or endogenic means, perhaps playing a more important role in the formation of the possible Martian "ice complexes" than might be expected were

  14. Caledonian Deformation in Polydeformed Pre-Mississippian Rocks of the Northeast Brooks Range, Alaska

    NASA Astrophysics Data System (ADS)

    Johnson, B. G.; Toro, J.; Benowitz, J.

    2013-12-01

    In the northeastern Brooks Range of Alaska there are polydeformed metasedimentary and metavolcanic rocks exposed below a major pre-Mississippian unconformity. Elsewhere in northern Alaska it has been challenging to correlate the tectonic fabrics of these early Paleozoic to Neoproterozoic rocks to the different orogenic events of the Arctic because of the strong overprint of Mesozoic and Tertiary Brookian deformation. However, our recent field investigations along the Kongakut and Aichiklik rivers of ANWR have identified an older (pre-Brookian) structural event based on the orientation of penetrative cleavage planes and a contrast in folding style to Brookian structures. Many of the cleavage planes are north dipping and orientated parallel to the axial planes of south-vergent folds. Although metamorphic grade is generally low, in localized areas the cleavage planes contain white micas, whose petrologic and isotopic characteristics indicate that they crystallized during fabric formation. 40Ar/39Ar dating of the white micas yield a metamorphic age of ~400 Ma (Early Devonian). This is evidence for a south-directed structural event which is contemporaneous with Caledonian deformation in East Greenland and Svalbard. Stratigraphicaly, the basement consists of a diverse package of highly deformed marine clastic sediments, and a thick section of basaltic to andesitic flows and volcaniclastic rocks, the Whale Mountain volcanics, which have a sharp southern contact but grade northward and upwards into the clastic rocks. All units are metamorphosed to lower greenschist facies. We are currently investigating the age and geochemical characteristics of the Whale Mountain volcanics to determine their tectonic affinity and role in the assemblage of the North Slope block of Northern Alaska.

  15. Friction of rocks

    USGS Publications Warehouse

    Byerlee, J.

    1978-01-01

    Experimental results in the published literature show that at low normal stress the shear stress required to slide one rock over another varies widely between experiments. This is because at low stress rock friction is strongly dependent on surface roughness. At high normal stress that effect is diminished and the friction is nearly independent of rock type. If the sliding surfaces are separated by gouge composed of Montmorillonite or vermiculite the friction can be very low. ?? 1978 Birkha??user Verlag.

  16. Opaque rock fragments

    SciTech Connect

    Abhijit, B.; Molinaroli, E.; Olsen, J.

    1987-05-01

    The authors describe a new, rare, but petrogenetically significant variety of rock fragments from Holocene detrital sediments. Approximately 50% of the opaque heavy mineral concentrates from Holocene siliciclastic sands are polymineralic-Fe-Ti oxide particles, i.e., they are opaque rock fragments. About 40% to 70% of these rock fragments show intergrowth of hm + il, mt + il, and mt + hm +/- il. Modal analysis of 23,282 opaque particles in 117 polished thin sections of granitic and metamorphic parent rocks and their daughter sands from semi-arid and humid climates show the following relative abundances. The data show that opaque rock fragments are more common in sands from igneous source rocks and that hm + il fragments are more durable. They assume that equilibrium conditions existed in parent rocks during the growth of these paired minerals, and that the Ti/Fe ratio did not change during oxidation of mt to hm. Geothermometric determinations using electron probe microanalysis of opaque rock fragments in sand samples from Lake Erie and the Adriatic Sea suggest that these rock fragments may have equilibrated at approximately 900/sup 0/ and 525/sup 0/C, respectively.

  17. Bounce Rock Dimple

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This panoramic camera image shows the hole drilled by the Mars Exploration Rover Opportunity's rock abrasion tool into the rock dubbed 'Bounce' on Sol 65 of the rover's journey. The tool drilled about 7 millimeters (0.3 inches) into the rock and generated small piles of 'tailings' or rock dust around the central hole, which is about 4.5 centimeters (1.7 inches) across. The image from sol 66 of the mission was acquired using the panoramic camera's 430 nanometer filter.

  18. Failure of cap-rock seals as determined from mechanical stratigraphy, stress history, and tensile-failure analysis of exhumed analogs

    DOE PAGES

    Petrie, E. S.; Evans, J. P.; Bauer, S. J.

    2014-11-01

    In this study, the sedimentologic and tectonic histories of clastic cap rocks and their inherent mechanical properties control the nature of permeable fractures within them. The migration of fluid through mm- to cm-scale fracture networks can result in focused fluid flow allowing hydrocarbon production from unconventional reservoirs or compromising the seal integrity of fluid traps. To understand the nature and distribution of subsurface fluid-flow pathways through fracture networks in cap-rock seals we examine four exhumed Paleozoic and Mesozoic seal analogs in Utah. We combine these outcrop analyses with subsidence analysis, paleoloading histories, and rock-strength testing data in modified Mohr–Coulomb–Griffith analysesmore » to evaluate the effects of differential stress and rock type on fracture mode.« less

  19. Failure of cap-rock seals as determined from mechanical stratigraphy, stress history, and tensile-failure analysis of exhumed analogs

    SciTech Connect

    Petrie, E. S.; Evans, J. P.; Bauer, S. J.

    2014-11-01

    In this study, the sedimentologic and tectonic histories of clastic cap rocks and their inherent mechanical properties control the nature of permeable fractures within them. The migration of fluid through mm- to cm-scale fracture networks can result in focused fluid flow allowing hydrocarbon production from unconventional reservoirs or compromising the seal integrity of fluid traps. To understand the nature and distribution of subsurface fluid-flow pathways through fracture networks in cap-rock seals we examine four exhumed Paleozoic and Mesozoic seal analogs in Utah. We combine these outcrop analyses with subsidence analysis, paleoloading histories, and rock-strength testing data in modified Mohr–Coulomb–Griffith analyses to evaluate the effects of differential stress and rock type on fracture mode.

  20. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin), Class III

    SciTech Connect

    Dutton, Shirley P.; Flanders, William A.

    2001-11-04

    The objective of this Class III project was demonstrate that reservoir characterization and enhanced oil recovery (EOR) by CO2 flood can increase production from slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico. Phase 1 of the project, reservoir characterization, focused on Geraldine Ford and East Ford fields, which are Delaware Mountain Group fields that produce from the upper Bell Canyon Formation (Ramsey sandstone). The demonstration phase of the project was a CO2 flood conducted in East Ford field, which is operated by Orla Petco, Inc., as the East Ford unit.

  1. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin), Class III

    SciTech Connect

    Dutton, Shirley P.; Flanders, William A.; Mendez, Daniel L.

    2001-05-08

    The objective of this Class 3 project was demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstone's of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost effective way to recover oil more economically through geologically based field development. This project was focused on East Ford field, a Delaware Mountain Group field that produced from the upper Bell Canyon Formation (Ramsey sandstone). The field, discovered in 9160, is operated by Oral Petco, Inc., as the East Ford unit. A CO2 flood was being conducted in the unit, and this flood is the Phase 2 demonstration for the project.

  2. Postcambrian stratified rocks of the northern part of the Baikal-Vitim fold area

    NASA Astrophysics Data System (ADS)

    Buldygerov, V. V.; Krainov, M. A.

    2012-09-01

    The Ordovician stratified rocks previously referred to Riphean or Vendian are widespread in the northern part of the Baikal-Vitim fold area. They include volcanosedimentary rocks which accumulated in continental riftlike troughs after Vendian-Cambrian platform regime and were accompanied by subvolcanic bodies. The coarse-clastic facies, frequently olistostromes with olistoplaques, are abundant in the marginal parts of the troughs. The sandy-silty-clay rocks dominate in the centre. The volcanic rocks represent the contrast rhyolite-basaltic series and compose paleovolcanoes of the central type, locally, complicated by calderas. Tuffaceous material is nearly almost present in synchronous sedimentary rocks. In the Ordovician, the northern part of the Baikal-Vitim fold area was an uplift of island arc type complicated by the riftlike troughs. It occupied the central part of the Baikal-Vitim arc. The location of the troughs was subjected to its structural plan. They were formed successively after the Riphean-Vendian Baikal-Muya volcano-plutonic belt. The uplift existed within a shallow basin occupying nearly the entire Siberian Platform and Baikal-Vitim fold area. The data obtained confirm that marine sedimentary basin with islands sometimes existed within the Baikal-Vitim fold area and was a part of the basin occupying the adjacent part of the Siberian Platform. The effect of pulsating plume in the northern part of the Baikal-Vitim fold area periodically, including Ordovician, led to the origination of the uplift and to renewal of tectonic and volcano-plutonic activity.

  3. Rock Bites into 'Bounce'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This panoramic camera image from the Mars Exploration Rover Opportunity features the 6.44 millimeter (0.25 inch) deep hole ground into the rock dubbed 'Bounce' by the rover's rock abrasion tool. The tool took 2 hours and 15 minutes to grind the hole on sol 66 of the rover's journey. A combination of limited solar power and the rock's jagged texture led the rock abrasion tool team to set very aggressive grinding parameters to ensure that the end result was a full circle, suitable for a thorough read from the rover's spectrometers.

    Bounce's markedly different appearance (when compared to the rocks that were previously examined in the Eagle Crater outcrop) made it a natural target for rover research. In order to achieve an ideal position from which to grind into the rock, Opportunity moved in very close with its right wheel next to Bounce. In this image, the panoramic camera on the rover's mast is looking down, catching the tip of the solar panel which partially blocks the full circle ground by the rock abrasion tool.

    The outer ring consists of the cuttings from the rock, pushed out by the brushes on the grinding instrument. The dark impression at the top of the outer circle was caused by the instrument's contact mechanism which serves to stabilize it while grinding.

  4. Welcome to Rock Day

    ERIC Educational Resources Information Center

    Varelas, Maria; Benhart, Jeaneen

    2004-01-01

    At the beginning of the school year, the authors, a first-grade teacher and a teacher educator, worked together to "spice up" the first-grade science curriculum. The teacher had taught the unit Rocks, Sand, and Soil several times, conducting hands-on explorations and using books to help students learn about properties of rocks, but she felt the…

  5. Session: Hard Rock Penetration

    SciTech Connect

    Tennyson, George P. Jr.; Dunn, James C.; Drumheller, Douglas S.; Glowka, David A.; Lysne, Peter

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hard Rock Penetration - Summary'' by George P. Tennyson, Jr.; ''Overview - Hard Rock Penetration'' by James C. Dunn; ''An Overview of Acoustic Telemetry'' by Douglas S. Drumheller; ''Lost Circulation Technology Development Status'' by David A. Glowka; ''Downhole Memory-Logging Tools'' by Peter Lysne.

  6. Rock Cycle Roulette.

    ERIC Educational Resources Information Center

    Schmidt, Stan M.; Palmer, Courtney

    2000-01-01

    Introduces an activity on the rock cycle. Sets 11 stages representing the transitions of an earth material in the rock cycle. Builds six-sided die for each station, and students move to the stations depending on the rolling side of the die. Evaluates students by discussing several questions in the classroom. Provides instructional information for…

  7. Layered Rocks in Crater

    NASA Technical Reports Server (NTRS)

    2004-01-01

    19 June 2004 Exposures of layered, sedimentary rock are common on Mars. From the rock outcrops examined by the Mars Exploration Rover, Opportunity, in Meridiani Planum to the sequence in Gale Crater's central mound that is twice the thickness of of the sedimentary rocks exposed by Arizona's Grand Canyon, Mars presents a world of sediment to study. This unusual example, imaged by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), shows eroded layer outcrops in a crater in Terra Tyrrhena near 15.4oS, 270.5oW. Sedimentary rocks provide a record of past climates and events. Perhaps someday the story told by the rocks in this image will be known via careful field work. The image covers an area about 3 km (1.9 mi) wide and is illuminated by sunlight from the left.

  8. Exploring the techno-economic feasibility of mine rock waste utilisation in road works: The case of a mining deposit in Ghana.

    PubMed

    Agyeman, Stephen; Ampadu, Samuel I K

    2016-02-01

    Mine rock waste, which is the rock material removed in order to access and mine ore, is free from gold processing chemical contaminants but presents a significant environmental challenge owing to the large volumes involved. One way of mitigating the environmental and safety challenges posed by the large volume of mine rock waste stockpiled in mining communities is to find uses of this material as a substitute for rock aggregates in construction. This article reports on a study conducted to evaluate the engineering properties of such a mine deposit to determine its suitability for use as road pavement material. Samples of mine rock waste, derived from the granitic and granodioritic intrusive units overlying the gold-bearing metavolcanic rock and volcano-clastic sediments of a gold mining area in Ghana, were obtained from three mine rock waste disposal facilities and subjected to a battery of laboratory tests to determine their physical, mechanical, geotechnical, geometrical and durability properties. The overall conclusion was that the mine rock waste met all the requirements of the Ghana Ministry of Transportation specification for use as aggregates for crushed rock subbase, base and surface dressing chippings for road pavements. The recommendation is to process it into the required sizes for the various applications.

  9. Our World: The Rock Cycle

    NASA Video Gallery

    Find out how rocks brought to Earth by the Apollo astronauts have helped NASA learn more about the rock cycle. Compare igneous, sedimentary and metamorphic rocks found on Earth to three types of ro...

  10. Application of advanced reservoir characterization, simulation and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, West Texas (Delaware Basin). Annual report

    SciTech Connect

    Dutton, S.P.; Asquith, G.B.; Barton, M.D.; Cole, A.G.; Gogas, J.; Malik, M.A.; Clift, S.J.; Guzman, J.I.

    1997-11-01

    The objective of this project is to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover a higher percentage of the original oil in place through strategic placement of infill wells and geologically based field development. This project involves reservoir characterization of two Late Permian slope and basin clastic reservoirs in the Delaware Basin, West Texas, followed by a field demonstration in one of the fields. The fields being investigated are Geraldine Ford and Ford West fields in Reeves and Culberson Counties, Texas. Project objectives are divided into two major phases, reservoir characterization and implementation. The objectives of the reservoir characterization phase of the project were to provide a detailed understanding of the architecture and heterogeneity of the two fields, the Ford Geraldine unit and Ford West field. Reservoir characterization utilized 3-D seismic data, high-resolution sequence stratigraphy, subsurface field studies, outcrop characterization, and other techniques. Once reservoir characterized was completed, a pilot area of approximately 1 mi{sup 2} at the northern end of the Ford Geraldine unit was chosen for reservoir simulation. This report summarizes the results of the second year of reservoir characterization.

  11. Zinc Enrichments in the Rocks of Gale Crater, Mars Measured by MSL-APXS Reflect Both High Zn in Jake_M Rocks and the Concentration of Zn in Sedimentary Cements

    NASA Astrophysics Data System (ADS)

    Berger, J. A.; Schmidt, M. E.; Gellert, R.; Fisk, M. R.

    2014-12-01

    Zinc enrichments have been discovered by Curiosity's alpha-particle X-ray spectrometer (APXS) in Gale Crater, Mars. Mugearitic Jake_M class rocks have 80-925 ppm Zn (Zn error in APXS accuracy ~16%), which is higher than shergottites (49-90 ppm) [Meyer, 2012] and abraded Adirondack rocks in Gusev Crater (75-117 ppm) [Gellert et al., 2006], but similar to Irvine and Barnhill class rocks in Gusev (230-422 ppm) [Ming et al., 2008]. The source of Jake_M was enriched in Zn, possibly by partial melting of metasomatized mantle [Stolper et al., 2013; Schmidt et al., 2014]. Relative to Jake_M, most clastic rocks encountered in Gale (sols 0-687) are moderately enriched in Zn (500-1900 ppm). Surface alteration is unlikely to cause elevated Zn because soils have lower Zn (310 to 380 ppm). Excluding soils, veins, very dusty rocks, and high-Ni John Klein rocks, Zn correlates with Fe, Mn, Cr, and Ni (r = 0.83, 0.68, 0.72, and 0.67, respectively). The positive relationships suggest that Zn is mobilized with these metals, possibly precipitating in oxide sedimentary cements with Fe-oxides and/or in the Fe-rich amorphous component. In this subset of rocks, Zn does not correlate with Cl, Br, or S; widespread Zn-halogen salts and Zn-sulfides are unlikely. Notable exceptions are the float rocks Et_Then and Secure, which have high FeO (25-27 wt%) but low Zn (~230-490 ppm) and are interpreted to reflect a distinct cementation or rock coating episode. Two Gale targets <1 m apart at the Kimberly outcrop are highly enriched in Zn, demonstrating the localized nature of Zn enrichments: Windjana drill fines (3430-4680 ppm Zn) have high K2O (3.6 wt%), FeO (~26 wt%), MnO (~0.56 wt%), and Ni (~380 ppm); Stephen (~8150 ppm Zn), interpreted to have a MnO-rich (~4.5 wt%) coating, also has high Ni (~1285 ppm), Cl (~3.2 wt%), and Br (~1850 ppm). An igneous origin of the Zn enrichments in Jake M class rocks is likely, and hydrothermal and/or diagenetic processes probably concentrated Zn in the clastic

  12. Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008

    USGS Publications Warehouse

    Chapman, Melinda J.; Cravotta, Charles A.; Szabo, Zoltan; Lindsay, Bruce D.

    2013-01-01

    , arsenic, manganese, and zinc were detected in one or more water samples at concentrations greater than established human health-based criteria. Arsenic concentrations typically were less than 1 microgram per liter (µg/L) in most groundwater samples; however, concentrations of arsenic greater than 1 µg/L frequently were detected in groundwater from clastic lacustrine sedimentary rocks of the Early Mesozoic basin aquifers and from metamorphosed clastic sedimentary rocks of the Piedmont and Blue Ridge crystalline rock aquifers. Groundwater from these rock units had elevated pH compared to other rock units evaluated in this study. Of the nine samples for which arsenic concentration was greater than 10 µg/L, six were classified as oxic and three as anoxic, and seven had pH of 7.2 or greater. Manganese concentrations typically were less than 10 µg/L in most samples; however, 8.3 percent of samples from the Piedmont and Blue Ridge crystalline-rock aquifers and 3.0 percent of samples from the Early Mesozoic basin siliciclastic rock aquifers had manganese concentrations greater than the 300-µg/L health-based screening level. The positive correlation of manganese with iron and ammonia and the negative correlation of manganese with dissolved oxygen and nitrate are consistent with the reductive dissolution of manganese oxides in the aquifer. Zinc concentrations typically were less than 10 µg/L in the groundwater samples considered in the study, but 0.4 percent and 5.5 percent of the samples had concentrations greater than the health-based screening level of 2,000 µg/L and one-tenth of the health-based screening level, respectively. The mean rank concentration of zinc in groundwater from the quartz-rich sedimentary rock lithologic group was greater than that for other lithologic groups even after eliminating samples collected from wells constructed with galvanized casing. Approximately 90 percent of 275 groundwater samples had radon-222 concentrations that were greater than the

  13. Space Weathering of Rocks

    NASA Technical Reports Server (NTRS)

    Noble, Sarah

    2011-01-01

    Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. On the Moon, rocks make up only a very small percentage of the exposed surface and areas where rocks are exposed, like central peaks, are often among the least space weathered regions we find in remote sensing data. However, our studies of weathered Ap 17 rocks 76015 and 76237 show that significant amounts of weathering products can build up on rock surfaces. Because rocks have much longer surface lifetimes than an individual soil grain, and thus record a longer history of exposure, we can study these products to gain a deeper perspective on the weathering process and better assess the relative impo!1ance of various weathering components on the Moon. In contrast to the lunar case, on small asteroids, like Itokowa, rocks make up a large fraction of the exposed surface. Results from the Hayabusa spacecraft at Itokowa suggest that while the low gravity does not allow for the development of a mature regolith, weathering patinas can and do develop on rock surfaces, in fact, the rocky surfaces were seen to be darker and appear spectrally more weathered than regions with finer materials. To explore how weathering of asteroidal rocks may differ from lunar, a set of ordinary chondrite meteorites (H, L, and LL) which have been subjected to artificial space weathering by nanopulse laser were examined by TEM. NpFe(sup 0) bearing glasses were ubiquitous in both the naturally-weathered lunar and the artificially-weathered meteorite samples.

  14. Rock Garden Mosaic

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image mosaic of part of the 'Rock Garden' was taken by the Sojourner rover's left front camera on Sol 71 (September 14). The rock 'Shark' is at left center and 'Half Dome' is at right. Fine-scale textures on the rocks are clearly seen. Broken crust-like material is visible at bottom center.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  15. Dirty Rotten Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This false-color image taken by the panoramic camera on the Mars Exploration Rover Spirit shows a collection of rocks (upper right) at Gusev Crater that have captured the attention of scientists for their resemblance to rotting loaves of bread. The insides of the rocks appear to have been eroded, while their outer rinds remain more intact. These outer rinds are reminiscent of those found on rocks at Meridiani Planum's 'Eagle Crater.' This image was captured on sol 158 (June 13, 2004).

  16. Zapping Rocks on Mars

    ScienceCinema

    Wiens, Roger

    2016-07-12

    Better understanding Mars means better understanding its geology. That’s why, sitting atop NASA’s Curiosity rover, is ChemCam, an instrument built by Los Alamos National Laboratory that shoots lasers at Martian rocks and analyzes the data. After nearly 1,500 rock zaps, ChemCam has uncovered some surprising facts about the Red Planet, including the discovery of igneous rocks. Soon, a new Los Alamos-built instrument—the SuperCam—will ride aboard the Mars 2020 rover and bring with it enhanced capabilities to unlock new secrets about the planet.

  17. Zapping Rocks on Mars

    SciTech Connect

    Wiens, Roger

    2016-05-16

    Better understanding Mars means better understanding its geology. That’s why, sitting atop NASA’s Curiosity rover, is ChemCam, an instrument built by Los Alamos National Laboratory that shoots lasers at Martian rocks and analyzes the data. After nearly 1,500 rock zaps, ChemCam has uncovered some surprising facts about the Red Planet, including the discovery of igneous rocks. Soon, a new Los Alamos-built instrument—the SuperCam—will ride aboard the Mars 2020 rover and bring with it enhanced capabilities to unlock new secrets about the planet.

  18. Detached rock evaluation device

    DOEpatents

    Hanson, David R.

    1986-01-01

    A rock detachment evaluation device (10) having an energy transducer unit 1) for sensing vibrations imparted to a subject rock (172) for converting the sensed vibrations into electrical signals, a low band pass filter unit (12) for receiving the electrical signal and transmitting only a low frequency segment thereof, a high band pass filter unit (13) for receiving the electrical signals and for transmitting only a high frequency segment thereof, a comparison unit (14) for receiving the low frequency and high frequency signals and for determining the difference in power between the signals, and a display unit (16) for displaying indicia of the difference, which provides a quantitative measure of rock detachment.

  19. Weird 'Endurance' Rock Ahead

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken by the Mars Exploration Rover Opportunity shows a bizarre, lumpy rock dubbed 'Wopmay' on the inner slopes of 'Endurance Crater.' Scientists say the rock's unusual texture is unlike any others observed so far at Meridiani Planum. Wopmay measures approximately 1 meter (3.3 feet) across. The image was taken by the rover's panoramic camera on sol 195 (Aug. 11, 2004). Opportunity will likely travel to this or a similar rock in coming sols for a closer look at the alien surface.

  20. A model for Iapetan rifting of Laurentia based on Neoproterozoic dikes and related rocks

    USGS Publications Warehouse

    Burton, William C.; Southworth, Scott

    2010-01-01

    Geologic evidence of the Neoproterozoic rifting of Laurentia during breakup of Rodinia is recorded in basement massifs of the cratonic margin by dike swarms, volcanic and plutonic rocks, and rift-related clastic sedimentary sequences. The spatial and temporal distribution of these geologic features varies both within and between the massifs but preserves evidence concerning the timing and nature of rifting. The most salient features include: (1) a rift-related magmatic event recorded in the French Broad massif and the southern and central Shenandoah massif that is distinctly older than that recorded in the northern Shenandoah massif and northward; (2) felsic volcanic centers at the north ends of both French Broad and Shenandoah massifs accompanied by dike swarms; (3) differences in volume between massifs of cover-sequence volcanic rocks and rift-related clastic rocks; and (4) WNW orientation of the Grenville dike swarm in contrast to the predominately NE orientation of other Neoproterozoic dikes. Previously proposed rifting mechanisms to explain these features include rift-transform and plume–triple-junction systems. The rift-transform system best explains features 1, 2, and 3, listed here, and we propose that it represents the dominant rifting mechanism for most of the Laurentian margin. To explain feature 4, as well as magmatic ages and geochemical trends in the Northern Appalachians, we propose that a plume–triple-junction system evolved into the rift-transform system. A ca. 600 Ma mantle plume centered east of the Sutton Mountains generated the radial dike swarm of the Adirondack massif and the Grenville dike swarm, and a collocated triple junction generated the northern part of the rift-transform system. An eastern branch of this system produced the Long Range dike swarm in Newfoundland, and a subsequent western branch produced the ca. 554 Ma Tibbit Hill volcanics and the ca. 550 Ma rift-related magmatism of Newfoundland.

  1. Scattering from Rock and Rock Outcrops

    DTIC Science & Technology

    2015-09-30

    distribution, bulk properties), (2) Acquiring and analyzing acoustic and environmental data collected during field tests in areas of known rock...resulted in good agreement between models and data. Figure 7 Scattering strength results from glacially plucked surface. The shape of the curves is...fact provide very similar fits to the SAS input data. Further analysis has shown that these estimate are only separated because their confidence

  2. Scattering from Rock and Rock Outcrops

    DTIC Science & Technology

    2014-09-30

    display a currently valid OMB control number. 1. REPORT DATE 30 SEP 2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND...outcrops are intended to address many of the open questions which exist for scattering from these types of surfaces and include increasing our basic...understanding of: 1) geoacoustic characteristics of rock relevant to scattering, 2) scattering strength versus grazing angle, and 3

  3. Tithonium Chasma's Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-565, 5 December 2003

    Exposures of light-toned, layered, sedimentary rocks are common in the deep troughs of the Valles Marineris system. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example from western Tithonium Chasma. The banding seen here is an eroded expression of layered rock. Sedimentary rocks can be composed of (1) the detritus of older, eroded and weathered rocks, (2) grains produced by explosive volcanism (tephra, also known as volcanic ash), or (3) minerals that were chemically precipitated out of a body of liquid such as water. These outcrops are located near 4.8oS, 89.7oW. The image covers an area 3 km (1.9 mi) wide and is illuminated from the lower left.

  4. Broken Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    18 May 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows broken-up blocks of sedimentary rock in western Candor Chasma. There are several locations in western Candor that exhibit this pattern of broken rock. The manner in which these landforms were created is unknown; it is possible that there was a landslide or a meteoritic impact that broke up the materials. One attribute that is known: in some of these cases, it seems that the rock was broken and then buried by later sedimentary rocks, before later being exhumed so that they can be seen from orbit today.

    Location near: 6.9oS, 75.5oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Winter

  5. Ancient Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-469, 31 August 2003

    The terraced area in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image is an outcropping of ancient, sedimentary rock. It occurs in a crater in western Arabia Terra near 10.8oN, 4.5oW. Sedimentary rocks provide a record of past environments on Mars. Field work will likely be required to begin to get a good understanding of the nature of the record these rocks contain. Their generally uniform thickness and repeated character suggests that deposition of fine sediment in this crater was episodic, if not cyclic. These rocks might be indicators of an ancient lake, or they might have been deposited from grains settling out of an earlier, thicker, martian atmosphere. This image covers an area 3 km (1.9 mi) across and is illuminated from the lower left.

  6. Writing Rock Music Reviews.

    ERIC Educational Resources Information Center

    Brown, Donal

    1980-01-01

    Suggests ways student reviewers of rock music groups can write better reviews. Among the suggestions made are that reviewers occasionally discuss the audience or what makes a particular group unique, support general comment with detail, and avoid ecstatic adjectives. (TJ)

  7. Rock in Its Elements

    ERIC Educational Resources Information Center

    MacCluskey, Thomas

    1969-01-01

    A discussion of the following musical elements of rock: rhythm, melody, harmony, and form. A impromptu analysis made at a session of the Youth Music Symposium, July 25, 1969. Remarks transcribed from tape. (Author/AP)

  8. Terby's Layered Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    14 March 2004 Layered rock outcrops are common all across Mars, and the Mars rover, Opportunity, has recently investigated some layered rocks in Meridiani Planum. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows layered sedimentary rocks in northern Terby Crater, located just north of the giant Hellas Basin near 27.5oS, 285.8oW. Hundreds of layers are exposed in a deposit several kilometers thick within Terby. A history of events that shaped the northern Hellas region is recorded in these rocks, just waiting for a person or robot to investigate. The picture covers an area 3 km (1.9 mi) across. Sunlight illuminates the scene from the left.

  9. Focus on the Rock.

    ERIC Educational Resources Information Center

    Shewell, John

    1994-01-01

    Describes historical accounts of the manipulation and importance of the Earth and its mineral resources. A foldout, "Out of the Rock," provides a collection of activities and information that helps make integration of the aforementioned concepts easy. (ZWH)

  10. Rock Outcrop Spectra

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The color image on the lower left shows a rock outcrop at Meridiani Planum, Mars. This image was taken by the panoramic camera on the Mars Exploration Rover Opportunity, looking north, and was acquired on the 4th sol, or martian day, of the rover's mission (Jan. 27, 2004). The yellow box outlines an area detailed in the top left image, which is a monochrome (single filter) image from the rover's panoramic camera. The top image uses solid colors to show several regions on or near the rock outcrop from which spectra were extracted: the dark soil above the outcrop (yellow), the distant horizon surface (aqua), a bright rock in the outcrop (green), a darker rock in the outcrop (red), and a small dark cobblestone (blue). Spectra from these regions are shown in the plot to the right.

  11. East Candor Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    24 September 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a thick, massive outcrop of light-toned rock exposed within eastern Candor Chasma, part of the vast Valles Marineris trough system. Dark, windblown sand has banked against the lower outcrop slopes. Outcrops such as this in the Valles Marineris chasms have been known since Mariner 9 images were obtained in 1972. However, the debate as to whether these represent sedimentary or igneous rocks has not been settled within the Mars science community. In either case, they have the physical properties of sedimentary rock (that is, they are formed of fine-grained materials), but some igneous rocks made up of volcanic ash may also exhibit these properties. This image is located near 7.8oS, 65.3oW, and covers an area approximately 3 km (1.9 mi) across. The scene is illuminated by sunlight from the lower left.

  12. Our World: Lunar Rock

    NASA Video Gallery

    Learn about NASA'€™s Lunar Sample Laboratory Facility at Johnson Space Center in Houston, Texas. See how NASA protects these precious moon rocks brought to Earth by the Apollo astronauts. Explore t...

  13. Fractal Geometry of Rocks

    SciTech Connect

    Radlinski, A.P.; Radlinska, E.Z.; Agamalian, M.; Wignall, G.D.; Lindner, P.; Randl, O.G.

    1999-04-01

    The analysis of small- and ultra-small-angle neutron scattering data for sedimentary rocks shows that the pore-rock fabric interface is a surface fractal (D{sub s}=2.82) over 3 orders of magnitude of the length scale and 10 orders of magnitude in intensity. The fractal dimension and scatterer size obtained from scanning electron microscopy image processing are consistent with neutron scattering data. {copyright} {ital 1999} {ital The American Physical Society}

  14. Rock and soil mechanics

    SciTech Connect

    Derski, W.; Izbicki, R.; Kisiel, I.; Mroz, Z.

    1988-01-01

    Although theoretical in character, this book provides a useful source of information for those dealing with practical problems relating to rock and soil mechanics - a discipline which, in the view of the authors, attempts to apply the theory of continuum to the mechanical investigation of rock and soil media. The book is in two separate parts. The first part, embodying the first three chapters, is devoted to a description of the media of interest. Chapter 1 introduces the main argument and discusses the essence of the discipline and its links with other branches of science which are concerned, on the one hand, with technical mechanics and, on the other, with the properties, origins, and formation of rock and soil strata under natural field conditions. Chapter 2 describes mechanical models of bodies useful for the purpose of the discourse and defines the concept of the limit shear resistance of soils and rocks. Chapter 3 gives the actual properties of soils and rocks determined from experiments in laboratories and in situ. Several tests used in geotechnical engineering are described and interconnections between the physical state of rocks and soils and their rheological parameters are considered.

  15. Weathering of rock 'Ginger'

    NASA Technical Reports Server (NTRS)

    1997-01-01

    One of the more unusual rocks at the site is Ginger, located southeast of the lander. Parts of it have the reddest color of any material in view, whereas its rounded lobes are gray and relatively unweathered. These color differences are brought out in the inset, enhanced at the upper right. In the false color image at the lower right, the shape of the visible-wavelength spectrum (related to the abundance of weathered ferric iron minerals) is indicated by the hue of the rocks. Blue indicates relatively unweathered rocks. Typical soils and drift, which are heavily weathered, are shown in green and flesh tones. The very red color in the creases in the rock surface correspond to a crust of ferric minerals. The origin of the rock is uncertain; the ferric crust may have grown underneath the rock, or it may cement pebbles together into a conglomerate. Ginger will be a target of future super-resolution studies to better constrain its origin.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  16. Paleontology and sedimentology of upper clastic member of Wanakah Formation, Chama basin, New Mexico: Lacustrine paleoenvironmental implications

    SciTech Connect

    Good, S.J.; Ridgley, J.L. )

    1989-09-01

    Lacustrine strata of the upper part of the Jurassic Wanakah Formation were restricted to the Chama basin of north-central New Mexico by mid-Jurassic tectonic activity in the Brazos and Nacimiento uplifts and along the Gallina-Archuleta anticlinorium. Lateral and vertical facies of the upper Wanakah exposed around the southern margin of the Chama basin indicate that the deeper part of the lake was north of the outcrop belt. The upper 3-5 m of the Wanakah consists of thin-bedded rippled sandstone, interbedded mudstone, and limestone containing trace fossils and freshwater mollusks characteristic of marginal lacustrine facies. Taphonomic studies of mollusks in the Wanakah Formation have been combined with application of ecophenotypic variation documented in extant unionid bivalves to produce paleoenvironmental interpretations of these lacustrine rocks.

  17. The potassic sedimentary rocks in Gale Crater, Mars, as seen by ChemCam on board Curiosity

    NASA Astrophysics Data System (ADS)

    Le Deit, L.; Mangold, N.; Forni, O.; Cousin, A.; Lasue, J.; Schröder, S.; Wiens, R. C.; Sumner, D.; Fabre, C.; Stack, K. M.; Anderson, R. B.; Blaney, D.; Clegg, S.; Dromart, G.; Fisk, M.; Gasnault, O.; Grotzinger, J. P.; Gupta, S.; Lanza, N.; Le Mouélic, S.; Maurice, S.; McLennan, S. M.; Meslin, P.-Y.; Nachon, M.; Newsom, H.; Payré, V.; Rapin, W.; Rice, M.; Sautter, V.; Treiman, A. H.

    2016-05-01

    The Mars Science Laboratory rover Curiosity encountered potassium-rich clastic sedimentary rocks at two sites in Gale Crater, the waypoints Cooperstown and Kimberley. These rocks include several distinct meters thick sedimentary outcrops ranging from fine sandstone to conglomerate, interpreted to record an ancient fluvial or fluvio-deltaic depositional system. From ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) chemical analyses, this suite of sedimentary rocks has an overall mean K2O abundance that is more than 5 times higher than that of the average Martian crust. The combined analysis of ChemCam data with stratigraphic and geographic locations reveals that the mean K2O abundance increases upward through the stratigraphic section. Chemical analyses across each unit can be represented as mixtures of several distinct chemical components, i.e., mineral phases, including K-bearing minerals, mafic silicates, Fe-oxides, and Fe-hydroxide/oxyhydroxides. Possible K-bearing minerals include alkali feldspar (including anorthoclase and sanidine) and K-bearing phyllosilicate such as illite. Mixtures of different source rocks, including a potassium-rich rock located on the rim and walls of Gale Crater, are the likely origin of observed chemical variations within each unit. Physical sorting may have also played a role in the enrichment in K in the Kimberley formation. The occurrence of these potassic sedimentary rocks provides additional evidence for the chemical diversity of the crust exposed at Gale Crater.

  18. Geochemical relationships of petroleum in Mesozoic reservoirs to carbonate source rocks of Jurassic Smackover Formation, southwestern Alabama

    SciTech Connect

    Claypool, G.E.; Mancini, E.A.

    1989-07-01

    Algal carbonate mudstones of the Jurassic Smackover Formation are the main source rocks for oil and condensate in Mesozoic reservoir rocks in southwestern Alabama. This interpretation is based on geochemical analyses of oils, condensates, and organic matter in selected samples of shale (Norphlet Formation, Haynesville Formation, Trinity Group, Tuscaloosa Group) and carbonate (Smackover Formation) rocks. Potential and probable oil source rocks are present in the Tuscaloosa Group and Smackover Formation, respectively. Extractable organic matter from Smackover carbonates has molecular and isotopic similarities to Jurassic oil. Although the Jurassic oils and condensates in southwestern Alabama have genetic similarities, they show significant compositional variations due to differences in thermal maturity and organic facies/lithofacies. Organic facies reflect different depositional conditions for source rocks in the various basins. The Mississippi Interior Salt basin was characterized by more continuous marine to hypersaline conditions, whereas the Manila and Conecuh embayments periodically had lower salnity and greater input of clastic debris and terrestrial organic matter. Petroleum and organic matter in Jurassic rocks of southwestern Alabama show a range of thermal transformations. The gas content of hydrocarbons in reservoirs increases with increasing depth and temperature. In some reservoirs where the temperature is above 266/degrees/F(130/degrees/C), gas-condensate is enriched in isotopically heavy sulfur, apparently derived from thermochemical reduction of Jurassic evaporite sulfate. This process also resulted in increase H/sub 2/S and CO in the gas, and depletion of saturated hydrocarbons in the condensate liquids.

  19. Advanced Oil Recovery Technologies for Improved Recovery from Slope Basin Clastic Reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, NM

    SciTech Connect

    Mark B. Murphy

    2005-09-30

    The Nash Draw Brushy Canyon Pool in Eddy County New Mexico was a cost-shared field demonstration project in the U.S. Department of Energy Class III Program. A major goal of the Class III Program was to stimulate the use of advanced technologies to increase ultimate recovery from slope-basin clastic reservoirs. Advanced characterization techniques were used at the Nash Draw Pool (NDP) project to develop reservoir management strategies for optimizing oil recovery from this Delaware reservoir. The objective of the project was to demonstrate that a development program, which was based on advanced reservoir management methods, could significantly improve oil recovery at the NDP. Initial goals were (1) to demonstrate that an advanced development drilling and pressure maintenance program can significantly improve oil recovery compared to existing technology applications and (2) to transfer these advanced methodologies to other oil and gas producers. Analysis, interpretation, and integration of recently acquired geological, geophysical, and engineering data revealed that the initial reservoir characterization was too simplistic to capture the critical features of this complex formation. Contrary to the initial characterization, a new reservoir description evolved that provided sufficient detail regarding the complexity of the Brushy Canyon interval at Nash Draw. This new reservoir description was used as a risk reduction tool to identify 'sweet spots' for a development drilling program as well as to evaluate pressure maintenance strategies. The reservoir characterization, geological modeling, 3-D seismic interpretation, and simulation studies have provided a detailed model of the Brushy Canyon zones. This model was used to predict the success of different reservoir management scenarios and to aid in determining the most favorable combination of targeted drilling, pressure maintenance, well stimulation, and well spacing to improve recovery from this reservoir. An Advanced

  20. Environmental controls on photosynthetic microbial mat distribution and morphogenesis on a 3.42 Ga clastic-starved platform.

    PubMed

    Tice, Michael M

    2009-12-01

    Three morphotypes of microbial mats are preserved in rocks deposited in shallow-water facies of the 3.42 Ga Buck Reef chert (BRC). Morphotype alpha consists of fine anastomosing and bifurcating carbonaceous laminations, which loosely drape underlying detrital grains or form silica-filled lenses. Morphotype beta consists of meshes of fine carbonaceous strands intergrown with detrital grains and dark laminations, which loosely drape coarse detrital grains. Morphotype gamma consists of fine, even carbonaceous laminations that tightly drape underlying detrital grains. Preservation of nearly uncompacted mat morphologies and detrital grains deposited during mat growth within a well-characterized sedimentary unit makes quantitative correlation between morphology and paleoenvironment possible. All mats are preserved in the shallowest-water interval of those rocks deposited below normal wave base and above storm wave base. This interval is bounded below by a transgressive lag formed during regional flooding and above by a small condensed section that marks a local relative sea-level maximum. Restriction of all mat morphotypes to the shallowest interval of the storm-active layer in the BRC ocean reinforces previous interpretations that these mats were constructed primarily by photosynthetic organisms. Morphotypes alpha and beta dominate the lower half of this interval and grew during deposition of relatively coarse detrital carbonaceous grains, while morphotype gamma dominates the upper half and grew during deposition of fine detrital carbonaceous grains. The observed mat distribution suggests that either light intensity or, more likely, small variations in ambient current energy acted as a first-order control on mat morphotype distribution. These results demonstrate significant environmental control on biological morphogenetic processes independent of influences from siliciclastic sedimentation.

  1. Miocene reef and nonreef carbonate rocks in Japan

    SciTech Connect

    Konishi, K.

    1988-01-01

    Japan's main islands experienced temperature climates throughout the Neogene with a tropical invasion around 16 Ma (early middle Miocene). This climatic warming, accompanied by a eustatic sea level rise, caused the unusual occurrence of reef facies, mangrove deposits, and lateritic beds in Japan. In cooler climates both before and after reef growth, sediments rich in bryozoan and algal material were widespread. Reef rocks emplaced as penecontemporaneous olistoliths in deep-water clastics at the Pacific coast of central Honshu are characterized by a wide lithologic spectrum, ranging from grainstone to bindstone. These rocks include rudstone and floatstone, which are rich in coralline algae (encrusting forms such as Lithophyllum and Mesophyllum and articulate forms such as Amphiroa) and codiacean algae (Halimeda) with hermatypic corals and large benthic formainifera (e.g., Nephrolepidina and Miogypsina) being less common. Two types of dolomite occur: (1) limpid dolomite with O/sup 18/ = -5.77 and with bipyramidal quartz and (2) microcrystalline dolomite with O/sup 18/ = 2.00 and with length-slow chalcedony. While microcrystalline dolomite tends to predominate in muddy matrix material, limpid dolomite appears to fill pores, some of which are moldic. Younger nonreef carbonate rocks, as occur on the Noto Peninsula of central Honshu, are commonly cross-bedded, contain Bryozoa, mollusks, small foraminifera, and echinoids, and are locally dolomitized. These dolomites are ascribed to a mixed-water origin. A different type of nonreef, yet reservoir-forming, dolostone occurs in the late middle Miocene of northeast Honshu and is interpreted to have formed as a transformation from bathyal opal.

  2. Geochemical characterisation, provenance, source and depositional environment of ‘Roches Argilo-Talqueuses’ (RAT) and Mines Subgroups sedimentary rocks in the Neoproterozoic Katangan Belt (Congo): Lithostratigraphic implications

    NASA Astrophysics Data System (ADS)

    Kampunzu, A. B.; Cailteux, J. L. H.; Moine, B.; Loris, H. N. B. T.

    2005-07-01

    The chemical characteristics of sedimentary rocks provide important clues to their provenance and depositional environments. Chemical analyses of 192 samples of Katangan sedimentary rocks from Kolwezi, Kambove-Kabolela and Luiswishi in the central African Copperbelt (Katanga, Congo) are used to constrain (1) the source and depositional environment of RAT and Mines Subgroup sedimentary rocks and (2) the geochemical relations between the rocks from these units and the debate on the lithostratigraphic position of the RAT Subgroup within the Katangan sedimentary succession. The geochemical data indicate that RAT, D. Strat., RSF and RSC are extremely poor in alkalis and very rich in MgO. SD are richer in alkalis, especially K 2O. Geochemical characteristics of RAT and Mines Subgroups sedimentary rocks indicate deposition under an evaporitic environment that evolved from oxidizing (Red RAT) to reducing (Grey RAT and Mines Subgroup) conditions. There is no chemical difference between RAT and fine-grained clastic rocks from the lower part of the Mines Subgroup. The geochemical data preclude the genetic model that RAT are syn-orogenic sedimentary rocks originating from Mines Group rocks by erosion and gravity-induced fragmentation in front of advancing nappes.

  3. [Enrichment and release of uranium during weathering of sedimentary rocks in Wujiang catchments].

    PubMed

    Song, Zhao-Liang; Liu, Cong-Qiang; Han, Gui-Lin; Wang, Zhong-Liang; Yang, Cheng; Liu, Zhan-Min

    2006-11-01

    Thirteen weathering profiles of typical rocks such as limestone, dolomitic limestone, dolomite, sillcalite, black shale and purple sandrock from Wujiang catchments were selected for discussing enrichment and release behavior of uranium (U) during rock weathering, and studying its impact on riverine U distribution in the catchments during weathering of these rocks with methods of correlation analysis and mass balance calculation. The purpose of this study is to improve our understanding on biogechemical cycling of U and set a basis for catchment protection against U pollution. The results show that the enrichment extent of U in soils from the Wujiang catchments is usually higher than that of upper continental crust (UCC), China soil (CS) and world soil (WS). The ability of enrichment and release of U is partly controlled by content of U in bedrocks, contents and adsorption ability of clay minerals and Fe-oxides/hydroxides in weathering profiles. Our study also reveals that release of U mainly from weathering of limestone and partly from weathering of dolomite and clastic rocks exerts an important control on riverine U distribution.

  4. Annual and Longer Sedimentary Rhythms of the Organic Rock Record of Titan's Circumpolar Seas and Lakes

    NASA Astrophysics Data System (ADS)

    Kargel, J. S.; Tan, S. P.; Marion, G. M.; Jennings, D. E.; Mastrogiuseppe, M.; Adidharma, H.

    2014-12-01

    Seasonality and phase equilibrium in Titan's lakes and seas will result in predictable sedimentary processes, deposits, and landforms. Calculated using CRYOCHEM, liquids on Titan should exhibit a counter-intuitive behavior where density increases with temperature but decreases with pressure, unless the temperature falls below 89.6 K. For warmer temperatures, the surface liquid of seas should flow toward the hottest spot; return flow may occur beneath the surface. Methane-rich liquid flowing southward from one interconnected northern sea to another will evaporate methane and concentrate ethane and other heavy hydrocarbons. In the north polar and circumpolar regions, a south-flowing river entering a sea from cold northerly uplands will inject a buoyant plume of low-density methane-rich liquid into the sea, unless the liquid at the inlet is heavily charged with dense solid phases or unless the lake is colder than 89.6 K. Generally north of (colder than) the seasonally shifting 89.6K transition (possible during the winter precisely when river discharges are high), a different behavior exists, whereby cold and methane-rich liquid forms denser liquids and flows across the bottom of the sea—possibly forming sub-sea channels as observed at Ligeia Mare. If the river carries clastic sediment denser than the methane liquid, the solids will undergo Stokes settling of the coarser fractions during periods of high river discharge, leaving the finest clastic fraction to undergo slow pelagic sedimentation throughout the year. From late spring to late summer, methane undergoes net evaporation from the sea, and solid organics that were saturated during the winter are likely to precipitate once warm weather starts. Hence, varves in Titan's seas are apt to consist of annual cycles of (1) winter: coarse clastics, (2) all dry season: fine-grained clastics, and (3) summer: evaporites. As Titan undergoes 'Milankovic' type variations in rotational obliquity and Saturn's orbital

  5. Pollack Crater's White Rock

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image of White Rock in Pollack crater was taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on February 3, 2007 at 1750 UTC (12:50 p.m. EST), near 8 degrees south latitude, 25 degrees east longitude. The CRISM image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 40 meters (132 feet) across. The region covered is roughly 20 kilometers (12 miles) long and 10 kilometers (6 miles) wide at its narrowest point.

    First imaged by the Mariner 9 spacecraft in 1972, the enigmatic group of wind-eroded ridges known as White Rock has been the subject of many subsequent investigations. White Rock is located on the floor of Pollack Crater in the Sinus Sabaeus region of Mars. It measures some 15 by 18 kilometers (9 by 11 miles) and was named for its light-colored appearance. In contrast-enhanced images, the feature's higher albedo or reflectivity compared with the darker material on the floor of the crater makes it appear white. In reality, White Rock has a dull, reddish color more akin to Martian dust. This higher albedo as well as its location in a topographic low suggested to some researchers that White Rock may be an eroded remnant of an ancient lake deposit. As water in a desert lake on Earth evaporates, it leaves behind white-colored salts that it leached or dissolved out of the surrounding terrain. These salt deposits may include carbonates, sulfates, and chlorides.

    In 2001, the Thermal Emission Spectrometer (TES) on NASA's Mars Global Surveyor measured White Rock and found no obvious signature of carbonates or sulfates, or any other indication that White Rock holds evaporite minerals. Instead, it found Martian dust.

    CRISM's challenge was to obtain greater detail of White Rock's mineralogical composition and how it formed. The instrument operates at a different wavelength range than TES, giving it greater sensitivity to carbonate, sulfate and phyllosilicate (clay-like) minerals. It also

  6. Application of advanced reservoir characterization, simulation, and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, West Texas (Delaware Basin), Class III

    SciTech Connect

    Dutton, Shirley P.; Flanders, William A.; Zirczy, Helena H.

    2000-05-24

    The objective of this Class 3 project was to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost effective way to recover a higher percentage of the original oil in place through strategic placement of infill wells and geologically based field development. Phase 1 of the project, reservoir characterization, was completed this year, and Phase 2 began. The project is focused on East Ford field, a representative Delaware Mountain Group field that produces from the upper Bell Canyon Formation (Ramsey sandstone). The field, discovered in 1960, is operated by Oral Petco, Inc., as the East Ford unit. A CO{sub 2} flood is being conducted in the unit, and this flood is the Phase 2 demonstration for the project.

  7. Ganges Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    24 May 2004 Mariner 9 images acquired in 1972 first revealed a large, light-toned, layered mound in Ganges Chasma, part of the vast Valles Marineris trough system. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a higher-resolution view of these rocks than was achieved by Mariner 9 or Viking, and higher than can be obtained by Mars Odyssey or Mars Express. The image, with a resolution of about 3.7 meters (12 feet) per pixel, shows eroded layered rock outcrops in Ganges Chasma. These rocks record a history of events that occurred either in Ganges Chasma, or in the rocks brought to the surface by the opening of Ganges Chasma. Either way, the story they might tell could be as fascinating and unprecedented as the story told by sedimentary rocks investigated this year in Meridiani Planum by the Opportunity Mars Exploration Rover ... no one knows. The image is located near 7.3oS, 48.8oW, and covers an area about 3 km (1.9 mi) across. The picture is illuminated by sunlight from the upper left.

  8. High resolution variability in the Quaternary Indian monsoon inferred from records of clastic input and paleo-production recovered during IODP Expedition 355

    NASA Astrophysics Data System (ADS)

    Hahn, Annette; Lyle, Mitchell; Kulhanek, Denise; Ando, Sergio; Clift, Peter

    2016-04-01

    The sediment cores obtained from the Indus fan at Site U1457 during Expedition 355 of the International Ocean Discovery Program (IODP) contain a ca. 100m spliced section covering the past ca. 1Ma. We aim to make use of this unique long, mostly continuous climate archive to unravel the millennial scale atmospheric and oceanic processes linked to changes in the Indian monsoon climate over the Quaternary glacial-interglacial cycles. Our aim is to fill this gap using fast, cost-efficient methods (Fourier Transform Infrared Spectroscopy [FTIRS] and X-ray Fluorescence [XRF] scanning) which allow us to study this sequence at a millennial scale resolution (2-3cm sampling interval). An important methodological aspect of this study is developing FTIRS as a method for the simultaneous estimation of the sediment total inorganic carbon and organic carbon content by using the specific fingerprint absorption spectra of minerals (e.g. calcite) and organic sediment components. The resulting paleo-production proxies give indications of oceanic circulation patterns and serve as a direct comparison to the XRF scanning data. Initial results show that variability in paleo-production is accompanied by changes in the quantity and composition of clastic input to the site. Phases of increased deposition of terrigenous material are enriched in K, Al, Fe and Si. Both changes in the weathering and erosion focus areas affect the mineralogy and elemental composition of the clastic input as grain size and mineralogical changes are reflected in the ratios of lighter to heavier elements. Furthermore, trace element compositions (Zn, Cu, Mn) give indications of diagenetic processes and contribute to the understanding of the depositional environment. The resulting datasets will lead to a more comprehensive understanding of the interplay of the local atmospheric and oceanic circulation processes over glacial-interglacial cycles; an essential prerequisite for regional predictions of global climate

  9. Facies analysis of Late Proterozoic through Lower Cambrian rocks of the Death Valley regional ground-water system and surrounding areas, Nevada and California

    SciTech Connect

    Sweetkind, D.S.; White, D.K.

    2002-03-15

    Late Proterozoic through Lower Cambrian rocks in the southern Great Basin form a westward-thickening wedge of predominantly clastic deposits that record deposition on the early western shelf edge of western North America (Stewart and Poole, 1974; Poole and others, 1992). Regional analyses of geologic controls on ground-water flow in the southern Great Basin typically combined lithostratigraphic units into more general hydrogeologic units that have considerable lateral extent and distinct hydrologic properties. The Late Proterozoic through Lower Cambrian rocks have been treated as a single hydrogeologic unit, named the lower clastic aquitard (Winograd and Thordarson, 1975) or the quartzite confining unit (Laczniak and others, 1996), that serves as the hydrologic basement to the flow system. Although accurate in a general sense, this classification ignores well-established facies relations within these rocks that might increase bedrock permeability and locally influence ground-water flow . This report presents a facies analysis of Late Proterozoic through Lower Cambrian rocks (hereafter called the study interval) in the Death Valley regional ground-water flow system - that portion of the southern Great Basin that includes Death Valley, the Nevada Test Site, and the potential high-level nuclear waste underground repository at Yucca Mountain (fig. 1). The region discussed in this report, hereafter called the study area, covers approximately 100,000 km2 (lat 35 degrees-38 degrees 15'N., long 115 degrees-118 degrees W.). The purpose of this analysis is to provide a general documentation of facies transitions within the Late Proterozoic through Lower Cambrian rocks in order to provide an estimate of material properties (via rock type, grain size, and bedding characteristics) for specific hydrogeologic units to be included in a regional ground-water flow model.

  10. The cretaceous source rocks in the Zagros Foothills of Iran: An example of a large size intracratonic basin

    SciTech Connect

    Bordenave, M.L. ); Huc, A.Y. )

    1993-02-01

    The Zagros orogenic belt of Iran is one of the world most prolific petroleum producing area. However, most of the oil production is originated from a relatively small area, the 60,000 km[sup 2] wide Dezful Embayment which contains approximately 12% of the proven oil global reserves. The distribution of the oil and gas fields results from the area extent of six identified source rock layers, their thermal history and reservoir, cap rock and trap availability. In this paper, the emphasis is three of the layers of Cretaceous sources rocks. The Garau facies was deposited during the Neocomian to Albian interval over Lurestan, Northeast Khuzestan and extends over the extreme northeast part of Fars, the Kazhdumi source rock which deposited over the Dezful Embayment, and eventually the Senonian Gurpi Formation which has marginal source rock characteristics in limited areas of Khuzestan and Northern Fars. The deposition environment of these source rock layers corresponds to semipermanent depressions, included in an overall shallow water intracratonic basin communicating with the South Tethys Ocean. These depressions became anoxic when climatic oceanographical and geological conditions were adequate, i.e., humid climate, high stand water, influxes of fine grained clastics and the existence of sills separating the depression from the open sea. Distribution maps of these source rock layers resulting from extensive field work and well control are also given. The maturation history of source rocks is reconstructed from a set of isopachs. It was found that the main contributor to the oil reserves is the Kazhdumi source rock which is associated with excellent calcareous reservoirs.

  11. Faulted Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    27 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows some of the layered, sedimentary rock outcrops that occur in a crater located at 8oN, 7oW, in western Arabia Terra. Dark layers and dark sand have enhanced the contrast of this scene. In the upper half of the image, one can see numerous lines that off-set the layers. These lines are faults along which the rocks have broken and moved. The regularity of layer thickness and erosional expression are taken as evidence that the crater in which these rocks occur might once have been a lake. The image covers an area about 1.9 km (1.2 mi) wide. Sunlight illuminates the scene from the lower left.

  12. Sedimentary Rock Layers

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-348, 2 May 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image acquired in March 2003 shows dozens of repeated layers of sedimentary rock in a western Arabia Terra crater at 8oN, 7oW. Wind has sculpted the layered forms into hills somewhat elongated toward the lower left (southwest). The dark patches at the bottom (south) end of the image are drifts of windblown sand. These sedimentary rocks might indicate that the crater was once the site of a lake--or they may result from deposition by wind in a completely dry, desert environment. Either way, these rocks have something important to say about the geologic history of Mars. The area shown is about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left.

  13. Ladon Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    6 June 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, layered, sedimentary rocks exposed by the fluids that carved the Ladon Valles system in the Erythraeum region of Mars. These rocks are so ancient that their sediments were deposited, cemented to form rock, and then eroded by the water (or other liquid) that carved Ladon Valles, so far back in Martian history that such liquids could still flow on the planet's surface.

    Location near: 20.8oS, 30.0oW Image width: 3 km (1.9 mi Illumination from: upper left Season: Southern Spring

  14. Gale Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-439, 1 August 2003

    Gale Crater, located in the Aeolis region near 5.5oS, 222oW, contains a mound of layered sedimentary rock that stands higher than the rim of the crater. This giant mound suggests that the entire crater was not only once filled with sediment, it was also buried beneath sediment. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows some of the eroded remains of the sedimentary rock that once filled Gale Crater. The layers form terraces; wind has eroded the material to form the tapered, pointed yardang ridges seen here. The small circular feature in the lower right quarter of the picture is a mesa that was once a small meteor impact crater that was filled, buried, then exhumed from within the sedimentary rock layers exposed here. This image is illuminated from the left.

  15. Rock Deformation Meeting

    NASA Astrophysics Data System (ADS)

    Green, Harry

    The Third Rock Deformation Colloquium was held December 4, 1989, at the AGU Fall Meeting in San Francisco. Steve Kirby of the U.S. Geological Survey, Menlo Park, Calif., reported on actions taken by the rock deformation steering committee. Brian Wernicke of Harvard University, Cambridge, Mass., talked on the structural geology of the Great Basin.The steering committee voted for “Committee on Deformation of Earth Materials” as the name for the AGU technical committee on rock deformation, Kirby said. Considerable discussion has occurred in the steering committee over our relationship to the AGU Mineral Physics Committee. Indeed, Kirby will become chairman of that committee in 1990, underlining the overlap of the two groups. It was agreed that we will pursue closer association with Mineral Physics.

  16. Eos Chaos Rocks

    NASA Technical Reports Server (NTRS)

    2006-01-01

    11 January 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, layered rock outcrops in Eos Chaos, located near the east end of the Valles Marineris trough system. The outcrops occur in the form of a distinct, circular butte (upper half of image) and a high slope (lower half of image). The rocks might be sedimentary rocks, similar to those found elsewhere exposed in the Valles Marineris system and the chaotic terrain to the east of the region.

    Location near: 12.9oS, 49.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Southern Summer

  17. Digital carbonate rock physics

    NASA Astrophysics Data System (ADS)

    Saenger, Erik H.; Vialle, Stephanie; Lebedev, Maxim; Uribe, David; Osorno, Maria; Duda, Mandy; Steeb, Holger

    2016-08-01

    Modern estimation of rock properties combines imaging with advanced numerical simulations, an approach known as digital rock physics (DRP). In this paper we suggest a specific segmentation procedure of X-ray micro-computed tomography data with two different resolutions in the µm range for two sets of carbonate rock samples. These carbonates were already characterized in detail in a previous laboratory study which we complement with nanoindentation experiments (for local elastic properties). In a first step a non-local mean filter is applied to the raw image data. We then apply different thresholds to identify pores and solid phases. Because of a non-neglectable amount of unresolved microporosity (micritic phase) we also define intermediate threshold values for distinct phases. Based on this segmentation we determine porosity-dependent values for effective P- and S-wave velocities as well as for the intrinsic permeability. For effective velocities we confirm an observed two-phase trend reported in another study using a different carbonate data set. As an upscaling approach we use this two-phase trend as an effective medium approach to estimate the porosity-dependent elastic properties of the micritic phase for the low-resolution images. The porosity measured in the laboratory is then used to predict the effective rock properties from the observed trends for a comparison with experimental data. The two-phase trend can be regarded as an upper bound for elastic properties; the use of the two-phase trend for low-resolution images led to a good estimate for a lower bound of effective elastic properties. Anisotropy is observed for some of the considered subvolumes, but seems to be insignificant for the analysed rocks at the DRP scale. Because of the complexity of carbonates we suggest using DRP as a complementary tool for rock characterization in addition to classical experimental methods.

  18. Sedimentary Rocks and Dunes

    NASA Technical Reports Server (NTRS)

    2004-01-01

    25 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows buttes composed of light-toned, sedimentary rock exposed by erosion within a crater occurring immediately west of Schiaparelli Basin near 4.0oS, 347.9oW. Surrounding these buttes is a field of dark sand dunes and lighter-toned, very large windblown ripples. The sedimentary rocks might indicate that the crater interior was once the site of a lake. The image covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left.

  19. Sedimentary Rock Remnants

    NASA Technical Reports Server (NTRS)

    2005-01-01

    29 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows knobs of remnant, wind-eroded, layered sedimentary rock that once completely covered the floor of a crater located west of the Sinus Meridiani region of Mars. Sedimentary rock outcrops are common throughout the Sinus Meridiani region and its surrounding cratered terrain.

    Location near: 2.2oN, 7.9oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Autumn

  20. Sedimentary Rock Layers

    NASA Technical Reports Server (NTRS)

    2004-01-01

    27 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows layers of sedimentary rock in a crater in western Arabia Terra. Layered rock records the history of a place, but an orbiter image alone cannot tell the entire story. These materials record some past episodes of deposition of fine-grained material in an impact crater that is much larger than the image shown here. The picture is located near 3.4oN, 358.7oW, and covers an area 3 km (1.9 mi.) wide. Sunlight illuminates the scene from the lower left.

  1. Opportunity Rocks Again!

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This high-resolution image captured by the Mars Exploration Rover Opportunity's panoramic camera highlights a portion of the puzzling rock outcropping that scientists eagerly wait to investigate. Presently, Opportunity is on its lander facing northeast; the outcropping lies to the northwest. These layered rocks measure only 10 centimeters (4 inches) tall and are thought to be either volcanic ash deposits or sediments carried by water or wind. Data from the panoramic camera's near-infrared, blue and green filters were combined to create this approximate true color image.

  2. Diverse Rock Named Squash

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image from the Sojourner rover's right front camera was taken on Sol 27. The Pathfinder lander is seen at middle left. The large rock at right, nicknamed 'Squash', exhibits a diversity of textures. It looks very similar to a conglomerate, a type of rock found on Earth that forms from sedimentary processes.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and managed the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  3. Theory of wing rock

    NASA Technical Reports Server (NTRS)

    Hsu, C. H.; Lan, C. E.

    1984-01-01

    A theory is developed for predicting wing rock characteristics. From available data, it can be concluded that wing rock is triggered by flow asymmetries, developed by negative or weakly positive roll damping, and sustained by nonlinear aerodynamic roll damping. A new nonlinear aerodynamic model that includes all essential aerodynamic nonlinearities is developed. The Beecham-Titchener method is applied to obtain approximate analytic solutions for the amplitude and frequency of the limit cycle based on the three degree-of-freedom equations of motion. An iterative scheme is developed to calculate the average aerodynamic derivatives and dynamic characteristics at limit cycle conditions. Good agreement between theoretical and experimental results is obtained.

  4. Rock Outcrops near Hellas

    NASA Technical Reports Server (NTRS)

    2004-01-01

    7 October 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows light-toned, layered rock outcrops in a pitted and eroded region just northeast of Hellas Planitia. The light-toned materials are most likely sedimentary rocks deposited early in martian history (but long after the Hellas Basin formed by a giant asteroid or comet impact). The scene also includes a plethora of large dark-toned, windblown ripples. The image is located near 27.2oS, 280.7oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

  5. Layered Rocks In Melas

    NASA Technical Reports Server (NTRS)

    2004-01-01

    20 June 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), image shows exposures of finely-bedded sedimentary rocks in western Melas Chasma, part of the vast Valles Marineris trough system. Rocks similar to these occur in neighboring west Candor Chasma, as well. The picture is located near 9.1oS, 74.5oW, and covers an area about 3 km (1.9 mi) wide. The scene is illuminated by sunlight from the left/upper left.

  6. Geology and depositional environments of the Guadalupian rocks of the northern Del Norte Mountains, West Texas

    USGS Publications Warehouse

    Rudine, S.F.; Wardlaw, B.R.; Rohr, D.M.; Grant, R.E.

    2000-01-01

    The Guadalupian rocks of the northern Del Norte Mountains were deposited in a foreland basin between land of the Marathon orogen and a carbonate shoal established on the geanticline separating the foreland basin from the Delaware basin. Deposition was alternately influenced by coarse clastic input from the orogen and carbonate shoal, which interrupted shallow basinal siltstone depletion. Relatively deeper-water deposition is characterized by carbonate input from the shoal, and relatively shallow-water deposition is characterized by sandstone input from the orogen. Deposition was in five general transgressive-regressive packages that include (1) the Road Canyon Formation and the first siltstone member and first sandstone member of the Word Formation, (2) the second siltstone member, Appel Ranch Member, and limy sandy siltstone member of the Word Formation, (3) the Vidrio Formation, (4) the lower and part of the middle members of the Altuda Formation, and (5) part of the middle and upper members of the Altuda Formation.

  7. Petrogenesis of lunar rocks: Rb-Sr constraints and lack of H2O

    NASA Technical Reports Server (NTRS)

    Albee, A. L.; Gancarz, A. J.

    1977-01-01

    Rb and Sr isotopic data and other chemical data indicate major lunar differentiation at about 4.6 AE (AE = 10 to the 9th power years) and very limited subsequent differentiation. The constraints of limited differentiation after 4.6 AE and the apparent lack of H2O on the moon, when applied to the derivation and petrogenesis of lunar samples, suggest the following: (1) soil samples, breccias, metaclastic rocks, and feldspathic basalts represent mixtures of repeatedly modified clastic material, which was utimately derived from materials formed during the 4.6 AE differentiation; and (2) mare basalts crystallized from melts which formed by partial melting, and which developed without equilibrium between the melt and crystalline residuum.

  8. Sedimentation, zoning of reservoir rocks in W. Siberian basin oil fields

    SciTech Connect

    Kliger, J.A. )

    1994-02-07

    A line pattern of well cluster spacing was chosen in western Siberia because of taiga, marshes, etc., on the surface. The zoning of the oil pools within productive Upper Jurassic J[sub 3] intervals is complicated. This is why until the early 1990s almost each third well drilled in the Shaimsky region on the western edge of the West Siberian basin came up dry. The results of development drilling would be much better if one used some sedimentological relationships of zoning of the reservoir rocks within the oil fields. These natural phenomena are: Paleobasin bathymetry; Distances from the sources of the clastic material; and Proximity of the area of deposition. Using the diagram in this article, one can avoid drilling toward areas where the sandstone pinch out, area of argillization of sand-stones, or where the probability of their absence is high.

  9. Fault Rock Variation as a Function of Host Rock Lithology

    NASA Astrophysics Data System (ADS)

    Fagereng, A.; Diener, J.

    2013-12-01

    Fault rocks contain an integrated record of the slip history of a fault, and thereby reflect the deformation processes associated with fault slip. Within the Aus Granulite Terrane, Namibia, a number of Jurassic to Cretaceous age strike-slip faults cross-cut Precambrian high grade metamorphic rocks. These strike-slip faults were active at subgreenschist conditions and occur in a variety of host rock lithologies. Where the host rock contains significant amounts of hydrous minerals, representing granulites that have undergone retrogressive metamorphism, the fault rock is dominated by hydrothermal breccias. In anhydrous, foliated rocks interlayered with minor layers containing hydrous phyllosilicates, the fault rock is a cataclasite partially cemented by jasper and quartz. Where the host rock is an isotropic granitic rock the fault rock is predominantly a fine grained black fault rock. Cataclasites and breccias show evidence for multiple deformation events, whereas the fine grained black fault rocks appear to only record a single slip increment. The strike-slip faults observed all formed in the same general orientation and at a similar time, and it is unlikely that regional stress, strain rate, pressure and temperature varied between the different faults. We therefore conclude that the type of fault rock here depended on the host rock lithology, and that lithology alone accounts for why some faults developed a hydrothermal breccia, some cataclasite, and some a fine grained black fault rock. Consequently, based on the assumption that fault rocks reflect specific slip styles, lithology was also the main control on different fault slip styles in this area at the time of strike-slip fault activity. Whereas fine grained black fault rock is inferred to represent high stress events, hydrothermal breccia is rather related to events involving fluid pressure in excess of the least stress. Jasper-bearing cataclasites may represent faults that experienced dynamic weakening as seen

  10. Depositional environments and diagenetic features of a Cretaceous clastic sequence, Fox Hills Sandstone of Northern Great Plains Province

    SciTech Connect

    Wilde, E.M.

    1986-08-01

    The Fox Hills Sandstone, youngest formation of the Montana Group, is a geographically extensive, thin unit that is composed primarily of silty sandstone and shale. This formation records the final withdrawal of the Upper Cretaceous epicontinental sea from the Western Interior of the US. It extends from central Canada southward through Montana, the Dakotas, Wyoming, and Colorado. This typical shoreline sequence is exposed along the flanks of the Cedar Creek anticline, which trends southeastward from eastern Montana into North and South Dakota. The upper Fox Hills consists of stacked, upward-fining, trough to planar cross-bedded sandstone bodies. These sequences grade laterally and vertically into interbedded clay and silt units containing root casts and are interpreted as deposits of a braided-stream system. A matrix mineral assemblage of chlorite, montmorillonite, calcite, and minor dolomite is characteristic of distributary channels and river mouth-bar facies. The lower Fox Hills consists of either irregularly stacked upward-coarsening, trough cross-bedded sand sequences or massive sand bodies separated by erosional surfaces. Outcrops locally contain the trace fossil Ophiomorpha or limestone concretions containing marine to brackish-water fossils, and have been interpreted as deposits of a rapidly advancing shoreline and strand plain. In the matrix, illite, kaolinite, and montmorillonite with minor calcite characterize beach, subtidal, and crevasse-splay environments. Diagenetic features include quartz overgrowths, clay alterations of potassium feldspar and rock fragments, and authigenic clay rims. Petrographic evidence indicates multiple source areas for these sediments and the primary influence of depositional environments on clay formation.

  11. Quantitative compositional analysis of sedimentary materials using thermal emission spectroscopy: 1. Application to sedimentary rocks

    NASA Astrophysics Data System (ADS)

    Thorpe, Michael T.; Rogers, A. Deanne; Bristow, Thomas F.; Pan, Cong

    2015-11-01

    Thermal emission spectroscopy is used to determine the mineralogy of sandstone and mudstone rocks as part of an investigation of linear spectral mixing between sedimentary constituent phases. With widespread occurrences of sedimentary rocks on the surface of Mars, critical examination of the accuracy associated with quantitative models of mineral abundances derived from thermal emission spectra of sedimentary materials is necessary. Although thermal emission spectroscopy has been previously proven to be a viable technique to obtain quantitative mineralogy from igneous and metamorphic materials, sedimentary rocks, with natural variation of composition, compaction, and grain size, have yet to be examined. In this work, we present an analysis of the thermal emission spectral (~270-1650 cm-1) characteristics of a suite of 13 sandstones and 14 mudstones. X-ray diffraction and traditional point counting procedures were all evaluated in comparison with thermal emission spectroscopy. Results from this work are consistent with previous thermal emission spectroscopy studies and indicate that bulk rock mineral abundances can be estimated within 11.2% for detrital grains (i.e., quartz and feldspars) and 14.8% for all other mineral phases present in both sandstones and mudstones, in comparison to common in situ techniques used for determining bulk rock composition. Clay-sized to fine silt-sized grained phase identification is less accurate, with differences from the known ranging from ~5 to 24% on average. Nevertheless, linear least squares modeling of thermal emission spectra is an advantageous technique for determining abundances of detrital grains and sedimentary matrix and for providing a rapid classification of clastic rocks.

  12. Origin of lacustrine rocks of Wilkins Peak Member, Wyoming

    SciTech Connect

    Sullivan, R.

    1985-06-01

    Wilkins Peak Member of the Green River Formation, with its interbeds of trona, oil shale, and dolomitic mudstone, contrasts markedly with the predominantly oilshale and calcitic mudstone sequences of the remainder of the succession. Much discussion has centered on the origin of these lacustrine rocks. A perennial meromictic (stratified) lake model has been replaced in recent years by a playa-lake model. The subsurface stratigraphy, however, was not well known when the models were developed. Paleogeographic reconstruction indicates that the region was subjected to variations in hydrographic conditions mainly in response to climatic fluctuations. During humid subtropical periods, widespread during the deposition of the Tipton Shale Member and Laney Member, the lakes were predominantly open meromictic systems with rivers entering the basin from the north. These environmental conditions were modified during deposition of the Wilkins Peak Member as the climate became more arid, and along the southern margin of the basin, shallow, saline-alkaline playa lakes formed in response to these changes. The widespread occurrence in the subsurface of fluvial clastic sequences of the Wasatch Formation associated with the Wilkins Peak Member would indicate that the playa lakes were frequently flooded and freshened by southern drainage systems. Therefore, the lakes were continuously undergoing modifications under the influence of climatic and possibly tectonic processes.

  13. Bounce Rock Close-Up

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This high-resolution panoramic camera blue filter image of the rock dubbed 'Bounce' was obtained up close, just before the rover placed its instruments on the rock for detailed study. The rock has a number of shiny surfaces and textures on it, some of which are unlike those seen in the Eagle Crater rock outcrop. Also, the rock was apparently moved or shaken when it was hit with the airbags, as can be seen by the gap and cracks in the soil around the rock. This image from sol 65 of the rover's journey was acquired using the panoramic camera's 430 nanometer filter.

  14. Origin of crude oil in eastern Gulf Coast: Upper Jurassic, Upper Cretaceous, and lower Tertiary source rocks

    SciTech Connect

    Sassen, R.

    1988-02-01

    Analysis of rock and crude oil samples suggests that three source rocks have given rise to most crude oil in reservoirs of the eastern Gulf Coast. Carbonate source rocks of the Jurassic Smackover Formation are characterized by algal-derived kerogen preserved in an anoxic and hypersaline environment, resulting in crude oils with distinct compositions. Migration commenced during the Cretaceous, explaining the emplacement of Smackover-derived crude oil in Jurassic and in some Cretaceous reservoirs. Upper Cretaceous clastic and carbonate source rocks are also present. Much crude oil in Upper Cretaceous reservoirs has been derived from organic-rich marine shales of the Tuscaloosa Formation. These shales are characterized by algal and higher plant kerogen, resulting in distinct crude oil compositions. Migration commenced during the Tertiary, but was mostly focused to Upper Cretaceous reservoirs. Lower Tertiary shales, including those of the Wilcox Formation, are quite organic-rich and include downdip marine facies characterized by both algal and higher plant kerogen. Crude oils in lower Tertiary reservoirs are dissimilar to crude oils from deeper and older source rocks. Migration from lower Tertiary shales commenced during the late Tertiary and charged Tertiary reservoirs. Although most crude oil in the eastern Gulf Coast has been emplaced by short-range migration, often with a strong vertical component, some long-range lateral migration (> 100 km) has occurred along lower Tertiary sands. The framework of crude oil generation and migration onshore has important implications with respect to origin of crude oil in the Gulf of Mexico.

  15. Reducing Rock Climbing Risks.

    ERIC Educational Resources Information Center

    Attarian, Aram

    1998-01-01

    Provides checklists that can be used as risk-management tools to evaluate rock-climbing programs: developing goals, policies, and procedures; inspecting the climbing environment; maintaining and inspecting equipment; protecting participants; and managing staff (hiring, training, retraining, and evaluating) and campers (experience level, needs, and…

  16. Slippery Rock University

    ERIC Educational Resources Information Center

    Arnhold, Robert W.

    2008-01-01

    Slippery Rock University (SRU), located in western Pennsylvania, is one of 14 state-owned institutions of higher education in Pennsylvania. The university has a rich tradition of providing professional preparation programs in special education, therapeutic recreation, physical education, and physical therapy for individuals with disabilities.…

  17. ROUGH ROCK DEMONSTRATION SCHOOL.

    ERIC Educational Resources Information Center

    FORBES, JACK

    THE ROUGH ROCK DEMONSTRATION SCHOOL IS LOCATED IN NORTHEASTERN ARIZONA, WHERE THE NAVAJO LANGUAGE IS UNIVERSALLY SPOKEN BY THE NAVAJO PEOPLE. IT IS LOCATED ON A NAVAJO RESERVATION AND WAS DESIGNED AS A BIA EXPERIMENTAL SCHOOL TO SERVE 200 ELEMENTARY PUPILS, MOST OF WHOM ARE IN THE BOARDING SCHOOL SITUATION. AN OBJECTIVE OF THE SCHOOL IS TO GAIN…

  18. The River Rock School.

    ERIC Educational Resources Information Center

    Gereaux, Teresa Thomas

    1999-01-01

    In the early 1920s, the small Appalachian community of Damascus, Virginia, used private subscriptions and volunteer labor to build a 15-classroom school made of rocks from a nearby river and chestnut wood from nearby forests. The school building's history, uses for various community activities, and current condition are described. (SV)

  19. Rocking and Rolling Rattlebacks

    ERIC Educational Resources Information Center

    Cross, Rod

    2013-01-01

    A rattleback is a well-known physics toy that has a preferred direction of rotation. If it is spun about a vertical axis in the "wrong" direction, it will slow down, start rocking from end to end, and then spin in the opposite (i.e. preferred) direction. Many articles have been written about rattlebacks. Some are highly mathematical and…

  20. 'Scarecrow' Climbs Rocks

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Scarecrow, a mobility-testing model for NASA's Mars Science Laboratory, easily traverses large rocks in the Mars Yard testing area at NASA's Jet Propulsion Laboratory.

    The Mars Science Laboratory rover is in development for launch in 2009. JPL, a division of the California Institute of Technology, Pasadena, manages the mission for the NASA Science Mission Directorate, Washington.

  1. Teaching the Rock Cycle with Ease.

    ERIC Educational Resources Information Center

    Bereki, Debra

    2000-01-01

    Describes a hands-on lesson for teaching high school students the concept of the rock cycle using sedimentary, metamorphic, and igneous rocks. Students use a rock cycle diagram to identify pairs of rocks. From the rock cycle, students explain on paper how their first rock became the second rock and vice versa. (PVD)

  2. Elastic Rock Heterogeneity Controls Brittle Rock Failure during Hydraulic Fracturing

    NASA Astrophysics Data System (ADS)

    Langenbruch, C.; Shapiro, S. A.

    2014-12-01

    For interpretation and inversion of microseismic data it is important to understand, which properties of the reservoir rock control the occurrence probability of brittle rock failure and associated seismicity during hydraulic stimulation. This is especially important, when inverting for key properties like permeability and fracture conductivity. Although it became accepted that seismic events are triggered by fluid flow and the resulting perturbation of the stress field in the reservoir rock, the magnitude of stress perturbations, capable of triggering failure in rocks, can be highly variable. The controlling physical mechanism of this variability is still under discussion. We compare the occurrence of microseismic events at the Cotton Valley gas field to elastic rock heterogeneity, obtained from measurements along the treatment wells. The heterogeneity is characterized by scale invariant fluctuations of elastic properties. We observe that the elastic heterogeneity of the rock formation controls the occurrence of brittle failure. In particular, we find that the density of events is increasing with the Brittleness Index (BI) of the rock, which is defined as a combination of Young's modulus and Poisson's ratio. We evaluate the physical meaning of the BI. By applying geomechanical investigations we characterize the influence of fluctuating elastic properties in rocks on the probability of brittle rock failure. Our analysis is based on the computation of stress fluctuations caused by elastic heterogeneity of rocks. We find that elastic rock heterogeneity causes stress fluctuations of significant magnitude. Moreover, the stress changes necessary to open and reactivate fractures in rocks are strongly related to fluctuations of elastic moduli. Our analysis gives a physical explanation to the observed relation between elastic heterogeneity of the rock formation and the occurrence of brittle failure during hydraulic reservoir stimulations. A crucial factor for understanding

  3. The Edwardsburg Formation and related rocks, Windermere Supergroup, central Idaho, USA

    USGS Publications Warehouse

    Lund, Karen; Aleinikoff, John N.; Evans, Karl V.

    2011-01-01

    In central Idaho, Neoproterozoic stratified rocks are engulfed by the Late Cretaceous Idaho batholith and by Eocene volcanic and plutonic rocks of the Challis event. Studied sections in the Gospel Peaks and Big Creek areas of west-central Idaho are in roof pendants of the Idaho batholith. A drill core section studied from near Challis, east-central Idaho, lies beneath the Challis Volcanic Group and is not exposed at the surface. Metamorphic and deformational overprinting, as well as widespread dismembering by the younger igneous rocks, conceals many primary details. Despite this, these rocks provide important links for regional correlations and have produced critical geochronological data for two Neoproterozoic glacial periods in the North American Cordillera. At the base of the section, the more than 700-m-thick Edwardsburg Formation (Fm.) contains interlayered diamictite and volcanic rocks. There are two diamictite-bearing members in the Edwardsburg Fm. that are closely related in time. Each of the diamictites is associated with intermediate composition tuff or flow rocks and the diamictites are separated by mafic volcanic rocks. SHRIMP U–Pb dating indicates that the lower diamictite is about 685±7 Ma, whereas the upper diamictite is 684±4 Ma. The diamictite units are part of a cycle of rocks from coarse clastic, to fine clastic, to carbonate rocks that, by correlation to better preserved sections, are thought to record an older Cryogenian glacial to interglacial period in the northern US Cordillera. The more than 75-m-thick diamictite of Daugherty Gulch is dated at 664±6 Ma. This unit is preserved only in drill core and the palaeoenvironmental interpretation and local stratigraphic relations are non-unique. Thus, the date for this diamictite may provide a date for a newly recognized glaciogenic horizon or may be a minimum age for the diamictite in the Edwardsburg Fm. The c. 1000-m-thick Moores Lake Fm. is an amphibolite facies diamictite in which glacial

  4. Chapter 39 The Edwardsburg Formation and related rocks, Windermere Supergroup, central Idaho, USA

    USGS Publications Warehouse

    Lund, Karen; Evans, Karl V.; Alienikoff, John N.

    2011-01-01

    In central Idaho, Neoproterozoic stratified rocks are engulfed by the Late Cretaceous Idaho batholith and by Eocene volcanic and plutonic rocks of the Challis event. Studied sections in the Gospel Peaks and Big Creek areas of west-central Idaho are in roof pendants of the Idaho batholith. A drill core section studied from near Challis, east-central Idaho, lies beneath the Challis Volcanic Group and is not exposed at the surface. Metamorphic and deformational overprinting, as well as widespread dismembering by the younger igneous rocks, conceals many primary details. Despite this, these rocks provide important links for regional correlations and have produced critical geochronological data for two Neoproterozoic glacial periods in the North American Cordillera. At the base of the section, the more than 700-m-thick Edwardsburg Formation (Fm.) contains interlayered diamictite and volcanic rocks. There are two diamictite-bearing members in the Edwardsburg Fm. that are closely related in time. Each of the diamictites is associated with intermediate composition tuff or flow rocks and the diamictites are separated by mafic volcanic rocks. SHRIMP U–Pb dating indicates that the lower diamictite is about 685±7 Ma, whereas the upper diamictite is 684±4 Ma. The diamictite units are part of a cycle of rocks from coarse clastic, to fine clastic, to carbonate rocks that, by correlation to better preserved sections, are thought to record an older Cryogenian glacial to interglacial period in the northern US Cordillera. The more than 75-m-thick diamictite of Daugherty Gulch is dated at 664±6 Ma. This unit is preserved only in drill core and the palaeoenvironmental interpretation and local stratigraphic relations are non-unique. Thus, the date for this diamictite may provide a date for a newly recognized glaciogenic horizon or may be a minimum age for the diamictite in the Edwardsburg Fm. The c. 1000-m-thick Moores Lake Fm. is an amphibolite facies diamictite in which glacial

  5. Variety and complexity in the mound of sedimentary rock in Gale Crater, Mars

    NASA Astrophysics Data System (ADS)

    Edgett, K. S.; Malin, M. C.

    2011-12-01

    NASA's Mars Science Laboratory rover, Curiosity, will be used to explore a portion of the lower stratigraphic record of the northwest side of a mound of layered rock ˜5 km thick in the 155 km-diameter Gale Crater. The rock materials are of a sedimentary origin, though the proportions of clastic sediment, tephra, and chemical precipitates are presently unknown. The mound is usually described as having lower and upper units separated by an erosional unconformity. However, some investigators recognize that it is considerably more complex. The stratigraphy displays vertical and lateral complexity; multiple erosional unconformities; filled, buried, interbedded, and exhumed or partly exhumed impact craters; evidence for deposition along the base of the mound followed by retreat of less-resistant rocks and abandonment of erosion-resistant materials shed from the mound; lithified sediments deposited at the mouths of streams that cut mound rock; inversion of intra-canyon stream channel sediment; and widening of canyons. On the northeast side of the mound there are landslide deposits, shed from the mound, that contain large blocks (10s to 100s of m) of layered rock in various orientations. The mound's highest feature does not exhibit layering and has been interpreted by some as being Gale's impact-generated central peak. However, its highest elevation exceeds that of most of the crater rim, an observation inconsistent with central peaks (where they occur at all) in martian craters of diameters similar to Gale. The layered materials that occur highest in the mound are also at elevations that exceed most of the crater rim; these exhibit repeated stratal packages that drape previously-eroded mound topography; they produce boulders as they erode, attesting to their lithified nature and requiring that a lithification process occurred in materials located ≥ 5 km above the deepest part of Gale. The lower mound strata, including the Curiosity field site, are diverse materials

  6. Microwave assisted hard rock cutting

    DOEpatents

    Lindroth, David P.; Morrell, Roger J.; Blair, James R.

    1991-01-01

    An apparatus for the sequential fracturing and cutting of subsurface volume of hard rock (102) in the strata (101) of a mining environment (100) by subjecting the volume of rock to a beam (25) of microwave energy to fracture the subsurface volume of rock by differential expansion; and , then bringing the cutting edge (52) of a piece of conventional mining machinery (50) into contact with the fractured rock (102).

  7. Geologic map of Paleozoic rocks in the Calico Hills, Nevada Test Site, southern Nevada

    SciTech Connect

    Cole, J.C.; Cashman, P.H.

    1998-11-01

    The Calico Hills area in the southwestern part of the Nevada Test Site, Nye County, Nevada, exposes a core of pre-Tertiary rocks surrounded by middle Miocene volcanic strata. This map portrays the very complex relationships among the pre-Tertiary stratigraphic units of the region. The Devonian and Mississippian rocks of the Calico Hills are distinct from age-equivalent carbonate-shelf or submarine-fan strata in other parts of the Nevada Test Site. The Calico Hills strata are interpreted to have been deposited beyond the continental shelf edge from alternating silicic and carbonate clastic sources. Structures of the Calico Hills area record the compounded effects of: (1) eastward-directed, foreland-vergent thrusting; (2) younger folds, kink zones, and thrusts formed by hinterland-vergent deformation toward northwesterly and northerly directions; and (3) low-angle normal faults that displaced blocks of Middle Paleozoic carbonate strata across the contractionally deformed terrane. All of these structures are older than any of the middle Miocene volcanic rocks that were erupted across the Calico Hills.

  8. Grain-size distribution of volcaniclastic rocks 1: A new technique based on functional stereology

    NASA Astrophysics Data System (ADS)

    Jutzeler, M.; Proussevitch, A. A.; Allen, S. R.

    2012-09-01

    The power of explosive volcanic eruptions is reflected in the grain size distribution and dispersal of their pyroclastic deposits. Grain size also forms part of lithofacies characteristics that are necessary to determine transport and depositional mechanisms responsible for producing pyroclastic deposits. However, the common process of welding and rock lithification prevents quantification of grain size by traditional sieving methods for deposits in the rock record. Here we show that functional stereology can be used to obtain actual 3D volume fractions of clast populations from 2D cross-sectional images. Tests made on artificially consolidated rocks demonstrate successful correlations with traditional sieving method. We show that the true grain size distribution is finer grained than its representation on a random 2D section. Our method allows the original size of vesicular pumice clasts to be estimated from their compacted shapes. We anticipate that the original grain-size distribution of welded ignimbrites can also be characterized by this method. Our method using functional stereology can be universally applied to any type of consolidated, weakly to non-deformed clastic material, regardless of grain size or age and therefore has a wide application in geology.

  9. Source terrains and diagenetic imprints of Cretaceous marine rocks of the Cordillera Oriental, Colombia

    SciTech Connect

    Segall, M.P.; Allen, R.B. ); Rubiano, J.; Sarmiento, L. )

    1993-02-01

    Cretaceous marine rocks of the western Cordillera Oriental of Colombia are exposed in stratigraphic sections which reveal multiple source terrains and variable diagenetic histories that were imposed by later thrusting XRD and petrographic analyses indicate that earliest Cretaceous rocks were derived from a nearly plutonic source (Triassic-Jurassic Ibague Batholith of the Cordillera Central) which provided feldspathic lithic fragments and clay-sized illite. High smectite concentrations in the overlying Hauterivian-Barremian strata reflect contemporaneous volcanism, possibly in the Cordillera Central. This signal decreased upsection to the upper Aptian, where detrital clays (kaolinite, chlorite, feldspar, amphibole) indicate a shift to a cratonic source, probably the Guayana Shield. Cratonic detrital input continues into the Turonian-Coniacian and is accompanies by high concentrations of smectite representing another period of volcanic activity. Later tectonic activity divided the area into two regions, each with unique diagenetic signatures. Three primary clastic sources are inferred for the section east of the thrust belt, however, the mineral assemblage is masked by later diagenesis. Sediments within the thrust belt show greater variability in the relative abundance of mineral assemblages and more poorly crystallized illite than occurs to the east of the thrust section. The preservation of much of the original mineralogic components within the thrust section indicates that these sediments have experienced only limited diagenetic overprinting as a result of a relatively short burial history. These contrasting signatures have important implications for hydrocarbon maturation within Cretaceous source rocks in a structurally complex region.

  10. Plutonic rocks of Jurassic age in the Alaska-Aleutian Range batholith: chemical variation and polarity.

    USGS Publications Warehouse

    Reed, B.I.; Miesch, A.T.; Lanphere, M.A.

    1983-01-01

    Plutonic rocks of Jurassic age exposed on the Pacific side of this batholith form a compositionally continuous calc-alkaline suite that ranges from hornblende gabbro to quartz monzonite. Tonalite and quartz diorite are the dominant rock types. Trend-surface analysis of 102 samples indicates that the direction of slope of the trend is approximately normal to the Jurassic magmatic arc. K2O and SiO2 increase towards the E-SE and the other oxides towards the W-NW. If the chemical trends reflect the approximate geometry of a palaeo-subduction zone, the polarity of the Jurassic magmatic arc is to the NW, i.e. subduction was directed towards the SE. Thus the palaeo-subduction zone is on the opposite side of the arc from the position that has generally been assumed, indicating that the Jurassic plutonic rocks were not generated in response to classical Andean-type convergent plate margins. The magmatic arc may have been formed in an intra-ocean environment and subsequently has been rafted northwards and accreted to this part of the N Pacific rim during the late Mesozoic. Middle and Upper Jurassic clastics underlying Cook Inlet to the SE and derived from the magmatic arc are classified as back-arc deposits, rather than as an arc-trench gap sequence.-L.C.H.

  11. Astronaut Charles Duke stands at rock adjacent to 'House Rock'

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Astronaut Charles M. Duke Jr., Apollo 16 lunar module pilot, stands at a rock adjacent (south) to the huge 'House Rock' (barely out of view at right edge). Note shadow at extreme right center where the two moon-exploring crewmen of the mission sampled what they referred to as the 'eastwest split of House Rock' or the open space between this rock and 'House Rock'. Duke has a sample bag in his hand, and a lunar surface rake leans against the large boulder.

  12. Influence of climate on deep-water clastic sedimentation: application of a modern model, Peru-Chile Trough, to an ancient system, Ouachita Trough

    USGS Publications Warehouse

    Edgar, N. Terence; Cecil, C. Blaine

    2003-01-01

    Traditionally, an abrupt and massive influx of siliciclastic sediments into an area of deposition has been attributed to tectonic uplift without consideration of the influence of climate or climatic change on rates of weathering, erosion, transportation, and deposition. With few exceptions, fluvial sediment transport is minimal in both extremely arid climates and in perhumid (everwet) climates. Maximum sediment transport occurs in climates characterized by strongly seasonal rainfall, where the effect of vegetation on erosion is minimal. The Peru–Chile trench and Andes Mountain system (P–CT/AMS) of the eastern Pacific Ocean clearly illustrates the effects of climate on rates of weathering, erosion, transport, and deep-sea sedimentation. Terrigenous sediment is virtually absent in the arid belt north of lat. 30° S in the P–CT, but in the belt of seasonal rainfall south of lat. 30° S terrigenous sediment is abundant. Spatial variations in the amount and seasonality of annual precipitation are now generally accepted as the cause for this difference. The spatial variation in sediment supply to the P–CT appears to be an excellent modern analogue for the temporal variation in sediment supply to certain ancient systems, such as the Ouachita Trough in the southern United States. By comparison, during the Ordovician through the early Mississippian, sediment was deposited at very slow rates as the Ouachita Trough moved northward through the southern hemisphere dry belt (lat. 10° S to lat. 30° S). The deposystem approached the tropical humid zone during the Mississippian, coincident with increased coarse clastic sedimentation. By the Middle Pennsylvanian (Atokan), the provenance area and the deposystem moved well into the tropical humid zone, and as much as 8,500 m of mineralogically mature (but texturally immature) quartz sand was introduced and deposited. This increase in clastic sediment deposition traditionally has been attributed solely to tectonic activity

  13. Unboxing Space Rocks

    ScienceCinema

    Bruck Syal, Megan

    2016-07-12

    The box was inconspicuous, but Lawrence Livermore National Laboratory (LLNL) postdoctoral researcher Megan Bruck Syal immediately knew its contents: two meteorites around the size of walnuts. They formed about 4.6 billion years ago and survived a history of violent collisions in the asteroid belt before being bumped into a near-Earth-object orbit by gravitational interactions with the planets. After finally raining down on Earth, these rocks were scavenged in Antarctica by researchers, sorted and classified at NASA Johnson Space Center, then mailed first-class to Bruck Syal. Now that these space rocks are in Bruck Syal’s hands, they are mere months away from fulfilling their destiny. They are to be vaporized by a high-powered laser, and the data they yield on asteroid deflection could one day save the planet.

  14. Soil and rock 'Yogi'

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Several possible targets of study for rover Sojourner's Alpha Proton X-Ray Spectrometer (APXS) instrument are seen in this image, taken by the Imager for Mars Pathfinder (IMP) on Sol 2. The smaller rock at left has been dubbed 'Barnacle Bill,' while the larger rock at right, approximately 3-4 meters from the lander, is now nicknamed 'Yogi.' Barnacle Bill is scheduled to be the first object of study for the APXS. Portions of a petal and deflated airbag are also visible at lower right.

    Mars Pathfinder was developed and managed by the Jet Propulsion Laboratory (JPL) for the National Aeronautics and Space Administration. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  15. Gale Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    15 April 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcroppings of layered, sedimentary rock in eastern Gale Crater. North-central Gale Crater is the site of a mound that is more than several kilometers thick and largely composed of sedimentary rocks that record a complex history of deposition and erosion. At one time, Gale Crater might have been completely filled and buried beneath the martian surface.

    Location near: 4.9oS, 221.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Winter

  16. Schiaparelli's Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    9 October 2004 Schiaparelli Basin is a large, 470 kilometer (292 miles) impact crater located east of Sinus Meridiani. The basin might once have been the site of a large lake--that is, if the sedimentary rocks exposed on its northwestern floor were deposited in water. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a 1.5 meter per pixel (5 ft per pixel) view of some of the light-toned, finely-bedded sedimentary rocks in northwestern Schiaparelli. The image is located near 1.0oS, 346.0oW, and covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left.

  17. Sedimentary Rock Outcrops

    NASA Technical Reports Server (NTRS)

    2004-01-01

    16 August 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded layered rock outcrops in a crater north of Meridiani Planum near 2.7oN, 359.1oW. The dozens and dozens of sedimentary rock layers of repeated thickness and similar physical properties at this location suggest that they may have been deposited in a lacustrine (lake) setting. The crater in which these layers occur may once have been completely filled and buried, as is the case for many craters in the Sinus Meridiani region. This image covers an area about 3 km (1.9 mi) across; sunlight illuminates the scene from the left.

  18. Sedimentary Rock Near Coprates

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-420, 13 July 2003

    This mosaic of two Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) narrow angle camera images, one from 2001, the other from 2003, shows light-toned, layered, sedimentary rock outcrops exposed on the floor of a trough that parallels Coprates Chasma in the Valles Marineris system. Layered rocks form the pages from which the history of a place can be read. It may be many years before the story is read, but or now at least we know where one of the books of martian history is found. This picture is located near 15.2oS, 60.1oW. Sunlight illuminates the scene from the left.

  19. Unboxing Space Rocks

    SciTech Connect

    Bruck Syal, Megan

    2016-05-09

    The box was inconspicuous, but Lawrence Livermore National Laboratory (LLNL) postdoctoral researcher Megan Bruck Syal immediately knew its contents: two meteorites around the size of walnuts. They formed about 4.6 billion years ago and survived a history of violent collisions in the asteroid belt before being bumped into a near-Earth-object orbit by gravitational interactions with the planets. After finally raining down on Earth, these rocks were scavenged in Antarctica by researchers, sorted and classified at NASA Johnson Space Center, then mailed first-class to Bruck Syal. Now that these space rocks are in Bruck Syal’s hands, they are mere months away from fulfilling their destiny. They are to be vaporized by a high-powered laser, and the data they yield on asteroid deflection could one day save the planet.

  20. Terby Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    27 December 2003 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows layered sedimentary rock outcrops in Terby Crater, located near 27.7oS, 285.4oW. The layered sediments in Terby are several kilometers thick, attesting to a long history of deposition in this ancient basin. The picture covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the upper left.

  1. Iani Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2005-01-01

    23 February 2005 This Mars Global Surveyor (MGS) Orbiter Camera (MOC) image shows light-toned sedimentary rocks exposed by erosion in the Iani Chaos region of Mars.

    Location near: 4.2oS, 18.7oW Image width: 1 km (0.6 mi) Illumination from: upper left Season: Southern Winter

  2. Melas Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    17 July 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows layered, sedimentary rock outcrops in southwestern Melas Chasma, one of the troughs of the vast Valles Marineris system. Sunlight illuminates this scene from the upper left; it is located near 9.8oS, 76.0oW, and covers an area about 3 km (1.9 mi) wide.

  3. DYNAMIC PROPERTIES OF ROCKS.

    DTIC Science & Technology

    common crustal rocks: polycrystalline and single crystal quartz (40-450 kbar), anorthosite (to 620 kbar), microcline (to 580 kbar) olivine (to 780 kbar...shock-induced transitions to high pressure polymorphic forms occur. Release adiabats of polycrystalline quartz and anorthosite descending from various... anorthosite descending from shock states above 120 kbar are quite steep, indicating irreversible transformation to denser materials believed to be high

  4. Eroded Sedimentary Rock

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-372, 26 May 2003

    This high resolution Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded, layered sedimentary rock exposures in an unnamed western Arabia Terra crater at 8oN, 7oW. The dark material is windblown sand; much of the erosion of these layers may have also been caused by wind. Sunlight illuminates the scene from the left.

  5. Soil Rock Analyzer

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A redesigned version of a soil/rock analyzer developed by Martin Marietta under a Langley Research Center contract is being marketed by Aurora Tech, Inc. Known as the Aurora ATX-100, it has self-contained power, an oscilloscope, a liquid crystal readout, and a multichannel spectrum analyzer. It measures energy emissions to determine what elements in what percentages a sample contains. It is lightweight and may be used for mineral exploration, pollution monitoring, etc.

  6. Rock pushing and sampling under rocks on Mars

    USGS Publications Warehouse

    Moore, H.J.; Liebes, S.; Crouch, D.S.; Clark, L.V.

    1978-01-01

    Viking Lander 2 acquired samples on Mars from beneath two rocks, where living organisms and organic molecules would be protected from ultraviolet radiation. Selection of rocks to be moved was based on scientific and engineering considerations, including rock size, rock shape, burial depth, and location in a sample field. Rock locations and topography were established using the computerized interactive video-stereophotogrammetric system and plotted on vertical profiles and in plan view. Sampler commands were developed and tested on Earth using a full-size lander and surface mock-up. The use of power by the sampler motor correlates with rock movements, which were by plowing, skidding, and rolling. Provenance of the samples was determined by measurements and interpretation of pictures and positions of the sampler arm. Analytical results demonstrate that the samples were, in fact, from beneath the rocks. Results from the Gas Chromatograph-Mass Spectrometer of the Molecular Analysis experiment and the Gas Exchange instrument of the Biology experiment indicate that more adsorbed(?) water occurs in samples under rocks than in samples exposed to the sun. This is consistent with terrestrial arid environments, where more moisture occurs in near-surface soil un- der rocks than in surrounding soil because the net heat flow is toward the soil beneath the rock and the rock cap inhibits evaporation. Inorganic analyses show that samples of soil from under the rocks have significantly less iron than soil exposed to the sun. The scientific significance of analyses of samples under the rocks is only partly evaluated, but some facts are clear. Detectable quantities of martian organic molecules were not found in the sample from under a rock by the Molecular Analysis experiment. The Biology experiments did not find definitive evidence for Earth-like living organisms in their sample. Significant amounts of adsorbed water may be present in the martian regolith. The response of the soil

  7. Salty Martian Rock

    NASA Technical Reports Server (NTRS)

    2004-01-01

    These plots, or spectra, show that a rock dubbed 'McKittrick' near the Mars Exploration Rover Opportunity's landing site at Meridiani Planum, Mars, has higher concentrations of sulfur and bromine than a nearby patch of soil nicknamed 'Tarmac.' These data were taken by Opportunity's alpha particle X-ray spectrometer, which produces a spectrum, or fingerprint, of chemicals in martian rocks and soil. The instrument contains a radioisotope, curium-244, that bombards a designated area with alpha particles and X-rays, causing a cascade of reflective fluorescent X-rays. The energies of these fluorescent X-rays are unique to each atom in the periodic table, allowing scientists to determine a target's chemical composition.

    Both 'Tarmac' and 'McKittrick' are located within the small crater where Opportunity landed. The full spectra are expressed as X-ray intensity (logarithmic scale) versus energy. When comparing two spectra, the relative intensities at a given energy are proportional to the elemental concentrations, however these proportionality factors can be complex. To be precise, scientists extensively calibrate the instrument using well-analyzed geochemical standards.

    Both the alpha particle X-ray spectrometer and the rock abrasion tool are located on the rover's instrument deployment device, or arm.

  8. Drawing rocks at primary school: a tool for emerging misconceptions and promoting conceptual change

    NASA Astrophysics Data System (ADS)

    Benciolini, L.; Muscio, G.

    2012-04-01

    Drawing rocks at primary school: a tool for emerging misconceptions and promoting conceptual change Luca Benciolini Dipartimento di Fisica, Chimica e Ambiente, Università di Udine (Italy) and Giuseppe Muscio Museo Friulano di Storia Naturale (Udine, Italy) In order to investigate spontaneous ideas of children about rock samples, the Museo Friulano di Storia Naturale in collaboration with the Università di Udine submitted six classrooms of fifth and fourth grade-students to a specific test. One hundred thirty-three students without a specific background in Earth Sciences were asked to give a) a written description of a rock sample; b) a drawing of the sample; c) a written short story about the sample. The selected thirty-five samples in the opinion of the researchers contain 255 geologically relevant self-evident characters such as fossils, clastic textures, planar discontinuities and so on. Childs spontaneously described 209 geological characters. Forty-seven fifth-grade students (group A) have been previously followed specific training in multisensory description of objects and observed the 90% of the geologically relevant characters. Group B (forty-three fifth-grade) and group C (forty-three fourth-grade) on the contrary, without any previous instructions discovered the 77%. In order to follow childs building their knowledge through experience we found that the main problem was the lack of consistency between written and drawing description. Heterogeneities as evident as a magmatic contact have been correctly represented by the drawing but it has not been worth of any attention in the written description. On the contrary, written description may sometimes contain careful description of the clastic sedimentary process but these criteria are applied for example to a travertine, without any relations with observed characters. Descriptions and drawing of rock outcrops performed by university students demonstrate the persistence of this attitude. Thus, groups B and

  9. Ophiolite Tectonics, Rock Magnetism and Palaeomagnetism, Cyprus

    NASA Astrophysics Data System (ADS)

    Borradaile, G. J.; Lagroix, F.; Hamilton, T. D.; Trebilcock, D.-A.

    2010-06-01

    Magnetic properties of minerals may be sensitive indicators of provenance. Remanence-bearing minerals (RBM) such as iron-titanium oxides, and matrix-forming minerals such as paramagnetic phyllosilicate or diamagnetic calcite yield different clues to provenance, strain history and tectonics, and are essential supplements for the full interpretation of palaeomagnetic data. Moreover, mineral magnetic properties provide magnetic-petrofabric indicators of tectonic strain, determine the suitability of sites for palaeomagnetism, and permit the restoration of palaeomagnetic vectors in some strained rocks. In the Cretaceous Troodos ophiolite (~88 Ma) magnetic properties are dictated by the relative importance of mafic silicates and largely primary, ophiolite-derived RBM. In its cover of deformed pelagic sedimentary rock, magnetic properties are dictated by the balance of clastic RBM versus matrix calcite and in some cases clay. The two larger Cretaceous ophiolite outcrops (Troodos & Akamas) share a common orientation of their plutonic flow fabrics, determined by magnetic methods. The dike complex shows fabrics indicating plume-like feeders spaced along and perpendicular to the spreading axis, with longevities >0.5 Ma. South of the ophiolite, its Cretaceous-Miocene limestone cover possesses ubiquitous tectonic petrofabrics inferred from anisotropy of magnetic susceptibility (AMS) and anisotropy of anhysteretic remanent susceptibility (AARM). Its foliation and maximum extension dip and plunge gently northward, sub-parallel to a common but previously unreported North-dipping stylolitic cleavage. In well-known localized areas, there are S-vergent thrusts and overturned folds. The S-vergent deformation fabrics are due to Late Miocene (pre-Messinian ~8 Ma) deformation. The structures are geometrically consistent with overthrusting of the Cretaceous Troodos-Akamas ophiolite, and its sedimentary cover, onto the underlying Triassic Mamonia terrane. The northern limit of pre

  10. Sedimentology of granite boulder conglomerates and associated clastics in the onshore section of the late Mesozoic Pletmos Basin (Western Cape, South Africa)

    NASA Astrophysics Data System (ADS)

    Bordy, Emese M.; America, Travis

    2016-07-01

    Along the southern margin of South Africa, intermountain rift successions, which comprise unusually large, rounded granite boulders and other coarse clastics, reveal an important geological history about the mid-Mesozoic extensional tectonics that lead to the break-up of Gondwana. These strata, mapped as part of the Mid to Upper Jurassic Enon Formation, allow the assessment of the nature, intensity and mode of sediment transport in onshore section of the Pletmos Basin, which is one of the late Mesozoic basins in southern Africa. Based on sedimentary facies analysis, palaeocurrent measurements and semi-quantitative palaeohydraulic calculations, the results suggest that the abundant coarse sediment was deposited by debris-flows and stream-flow floods on a proximal alluvial fan with high gradient alluvial channels. The floods were intense with mean flow velocity of ˜6 m3/s and peak discharge of ˜450 m3/s. While the role of climate in the sedimentation dynamics remains unknown, syn-sedimentary rift tectonics were likely significant and caused, north of the major boundary fault, the unroofing and denudation of the uplifted mountainous source areas, including the Late Ediacaran-Cambrian Maalgaten Granite Suite and the Siluro-Ordovician Table Mountain Group (Cape Supergroup).

  11. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin)

    SciTech Connect

    Dutton, S.P.; Flanders, W.A.; Guzman, J.I.; Zirczy, H.

    1999-06-08

    The objective of this Class III project is to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover a higher percentage of the original oil in place through geologically based field development. This year the project focused on reservoir characterization of the East Ford unit, a representative Delaware Mountain Group field that produces from the upper Bell Canyon Formation (Ramsey Sandstone). The field, discovered in 1960, is operated by Orla Petco, Inc., as the East Ford unit; it contained an estimated 19.8 million barrels (MMbbl) of original oil in place. Petrophysical characterization of the East Ford unit was accomplished by integrating core and log data and quantifying petrophysical properties from wireline logs. Most methods of petrophysical analysis that had been developed during an earlier study of the Ford Geraldine unit were successfully transferred to the East Ford unit. The approach that was used to interpret water saturation from resistivity logs, however, had to be modified because in some East Ford wells the log-calculated water saturation was too high and inconsistent with observations made during the actual production. Log-porosity to core-porosity transforms and core-porosity to core-permeability transforms were derived from the East Ford reservoir. The petrophysical data were used to map porosity, permeability, net pay, water saturation, mobil-oil saturation, and other reservoir properties.

  12. Three classes of Martian rocks

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In this portion of the 360-degree color gallery pan, looking to the northeast, the colors have been exaggerated to highlight the differences between rocks and soils. Visible are the downwind sides of rocks, not exposed to wind scouring like Barnacle Bill (which faces upwind). There is a close correspondence between the shapes and colors of the rocks. Three general classes of rocks are recognized: large rounded rocks with weathered coatings, small gray angular rocks lacking weathered coatings, and flat white rocks. The large rounded rocks in the distance, marked by the red arrows, are comparable to Yogi. Spectral properties show that these rocks have a highly weathered coating in addition to a distinctive shape. A second population of smaller, angular rocks (blue arrows) in the foreground have unweathered surfaces even on the downwind side, except where covered on their tops by drift. These are comparable to Barnacle Bill. They may have been emplaced at the site relatively recently, perhaps as ejecta from an impact crater, so they have not had time to weather as extensively as the larger older rocks. The third kind of rock (white arrows) is white and flat, and includes Scooby Doo in the foreground and a large deposit in the background called Baker's Bank. The age of the white rock relative to the other two classes is still being debated. One representative rock of each class (Yogi, Barnacle Bill, and Scooby Doo) has been measured by the rover.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  13. Grinding into Soft, Powdery Rock

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This hole in a rock dubbed 'Clovis' is the deepest hole drilled so far in any rock on Mars. NASA's Mars Exploration Rover Spirit captured this view with its microscopic imager on martian sol 217 (Aug. 12, 2004) after drilling 8.9 millimeters (0.35 inch) into the rock with its rock abrasion tool. The view is a mosaic of four frames taken by the microscopic imager. The hole is 4.5 centimeters (1.8 inches) in diameter. Clovis is key to a developing story about environmental change on Mars, not only because it is among the softest rocks encountered so far in Gusev Crater, but also because it contains mineral alterations that extend relatively deep beneath its surface. In fact, as evidenced by its fairly crumbly texture, it is possibly the most highly altered volcanic rock ever studied on Mars.

    Scientific analysis shows that the rock contains higher levels of the elements sulfur, chlorine, and bromine than are normally encountered in basaltic rocks, such as a rock dubbed 'Humphrey' that Spirit encountered two months after arriving on Mars. Humphrey showed elevated levels of sulfur, chlorine, and bromine only in the outermost 2 millimeters (less than 0.1 inch) of its surface. Clovis shows elevated levels of the same elements along with the associated softness of the rock within a borehole that is 4 times as deep. Scientists hope to compare Clovis to other, less-altered rocks in the vicinity to assess what sort of water-based processes altered the rock. Hypotheses include transport of sulfur, chlorine, and bromine in water vapor in volcanic gases; hydrothermal circulation (flow of volcanically heated water through rock); or saturation in a briny soup containing the same elements.

    In this image, very fine-grained material from the rock has clumped together by electrostatic attraction and fallen into the borehole. NASA/JPL/Cornell/USGS

  14. Uinta Arch Project: investigations of uranium potential in Precambrian X and older metasedimentary rocks in the Unita and Wasatch ranges, Utah and Colorado

    SciTech Connect

    Graff, P.J.; Sears, J.W.; Holden, G.S.

    1980-06-01

    This study is part of the United States Department of Energy's National Uranium Resource Evaluation Program to understand the geologic setting, amount, and availability of uranium resources within the boundaries of the United States. The systematic study of Precambrian quartz-pebble conglomerates and areas that may contain such conglomerates is an integral part of DOE's resource evaluation program, because deposits of world-wide importance occur in such terrains in Canada and South Africa, and because terrains similar to those producing uranium from quartz-pebble conglomerates exist elsewhere in the United States. Because of the ready availability of Tertiary sandstone and Colorado Plateau-type uranium deposits, large areas of Precambrian rocks in the US have not been fully assessed for uranium potential. Thus, the Uinta Arch Project was undertaken to assess the favorability of Precambrian metasedimentary rocks in northern Utah for deposits of uranium in Precambrian quartz-pebble conglomerates. Rocks of interest to this study are the thick, clastic sequences within the Uinta Arch that are considered to be of Early Proterozoic age. The Uinta Arch area is known to contain rocks which generally fit the lithologic characteristics that are understood to limit the occurrence of Precambrian fossil placers. However, detailed geology of these rocks and their exact fit to the model described for uraniferous conglomerates was not known. The primary goal of the Uinta Arch Project was to determine how well these Precambrian rocks resemble known deposits and to describe the favorability of placer uranium deposits.

  15. Rock Pore Structure as Main Reason of Rock Deterioration

    NASA Astrophysics Data System (ADS)

    Ondrášik, Martin; Kopecký, Miloslav

    2014-03-01

    Crashed or dimensional rocks have been used as natural construction material, decoration stone or as material for artistic sculptures. Especially old historical towns not only in Slovakia have had experiences with use of stones for construction purposes for centuries. The whole buildings were made from dimensional stone, like sandstone, limestone or rhyolite. Pavements were made especially from basalt, andesite, rhyolite or granite. Also the most common modern construction material - concrete includes large amounts of crashed rock, especially limestone, dolostone and andesite. However, rock as any other material if exposed to exogenous processes starts to deteriorate. Especially mechanical weathering can be very intensive if rock with unsuitable rock properties is used. For long it had been believed that repeated freezing and thawing in relation to high absorption is the main reason of the rock deterioration. In Slovakia for many years the high water absorption was set as exclusion criterion for use of rocks and stones in building industry. Only after 1989 the absorption was accepted as merely informational rock property and not exclusion. The reason of the change was not the understanding of the relationship between the porosity and rock deterioration, but more or less good experiences with some high porous rocks used in constructions exposed to severe weather conditions and proving a lack of relationship between rock freeze-thaw resistivity and water absorption. Results of the recent worldwide research suggest that understanding a resistivity of rocks against deterioration is hidden not in the absorption but in the structure of rock pores in relation to thermodynamic properties of pore water and tensile strength of rocks and rock minerals. Also this article presents some results of research on rock deterioration and pore structure performed on 88 rock samples. The results divide the rocks tested into two groups - group N in which the pore water does not freeze

  16. Evolution of Sedimentary Rocks

    NASA Astrophysics Data System (ADS)

    Veizer, J.; MacKenzie, F. T.

    2003-12-01

    For almost a century, it has been recognized that the present-day thickness and areal extent of Phanerozoic sedimentary strata increase progressively with decreasing geologic age. This pattern has been interpreted either as reflecting an increase in the rate of sedimentation toward the present (Barrell, 1917; Schuchert, 1931; Ronov, 1976) or as resulting from better preservation of the younger part of the geologic record ( Gilluly, 1949; Gregor, 1968; Garrels and Mackenzie, 1971a; Veizer and Jansen, 1979, 1985).Study of the rocks themselves led to similarly opposing conclusions. The observed secular (=age) variations in relative proportions of lithological types and in chemistry of sedimentary rocks (Daly, 1909; Vinogradov et al., 1952; Nanz, 1953; Engel, 1963; Strakhov, 1964, 1969; Ronov, 1964, 1982) were mostly given an evolutionary interpretation. An opposing, uniformitarian, approach was proposed by Garrels and Mackenzie (1971a). For most isotopes, the consensus favors deviations from the present-day steady state as the likely cause of secular trends.This chapter attempts to show that recycling and evolution are not opposing, but complementary, concepts. It will concentrate on the lithological and chemical attributes of sediments, but not deal with the evolution of sedimentary mineral deposits (Veizer et al., 1989) and of life ( Sepkoski, 1989), both well amenable to the outlined conceptual treatment. The chapter relies heavily on Veizer (1988a) for the sections dealing with general recycling concepts, on Veizer (2003) for the discussion of isotopic evolution of seawater, and on Morse and Mackenzie (1990) and Mackenzie and Morse (1992) for discussion of carbonate rock recycling and environmental attributes.

  17. Melas Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    28 August 2004 Light-toned, layered, sedimentary rock outcrops are common within the vast martian Valles Marineris trough system. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a recent example from southern Melas Chasma at 1.5 m/pixel (5 ft/pixel) resolution. The image is located near 11.3oS, 73.9oW, and covers an area about 1.8 km (1.1 mi) across. Sunlight illuminates the scene from the upper left.

  18. Sedimentary Rocks in Melas

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This Mars Global Surveyor (MGS) Orbiter Camera (MOC) image shows a butte and several other landforms eroded into light-toned, layered, sedimentary rock in southern Melas Chasma. Melas is part of the vast Valles Marineris trough system.

    Location near: 11.8oS, 74.6oW Image width: 3.0 km (1.9 mi) Illumination from: lower left Season: Southern Spring

  19. Sedimentary Rocks in Ganges

    NASA Technical Reports Server (NTRS)

    2004-01-01

    13 November 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows portions of two massifs composed of light-toned, sedimentary rock in Ganges Chasma, part of the Valles Marineris trough system. On the steeper slopes in this vista, dry talus shed from the outcrop has formed a series of dark fans. Surrounded by dark, windblown sand, these landforms are located near 8.6oS, 46.8oW. The image covers an area approximately 3 km (1.9 mi) across and sunlight illuminates the scene from the upper left.

  20. Sedimentary Rock in Candor

    NASA Technical Reports Server (NTRS)

    2005-01-01

    11 February 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows dozens of light- and a few dark-toned sedimentary rock layers exposed by faulting and erosion in western Candor Chasma, part of the vast Valles Marineris trough system.

    Location near: 6.5oS, 77.0oW Image width: 3.0 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

  1. From stones to rocks

    NASA Astrophysics Data System (ADS)

    Mortier, Marie-Astrid; Jean-Leroux, Kathleen; Cirio, Raymond

    2013-04-01

    With the Aquila earthquake in 2009, earthquake prediction is more and more necessary nowadays, and people are waiting for even more accurate data. Earthquake accuracy has increased in recent times mainly thanks to the understanding of how oceanic expansion works and significant development of numerical seismic prediction models. Despite the improvements, the location and the magnitude can't be as accurate as citizen and authorities would like. The basis of anticipating earthquakes requires the understanding of: - The composition of the earth, - The structure of the earth, - The relations and movements between the different parts of the surface of the earth. In order to answer these questions, the Alps are an interesting field for students. This study combines natural curiosity about understanding the predictable part of natural hazard in geology and scientific skills on site: observing and drawing landscape, choosing and reading a representative core drilling, replacing the facts chronologically and considering the age, the length of time and the strength needed. This experience requires students to have an approach of time and space radically different than the one they can consider in a classroom. It also limits their imagination, in a positive way, because they realize that prediction is based on real data and some of former theories have become present paradigms thanks to geologists. On each location the analyzed data include landscape, core drilling and the relation established between them by students. The data is used by the students to understand the meaning, so that the history of the formation of the rocks tells by the rocks can be explained. Until this year, the CBGA's perspective regarding the study of the Alps ground allowed students to build the story of the creation and disappearance of the ocean, which was a concept required by French educational authorities. But not long ago, the authorities changed their scientific expectations. To meet the

  2. Isotope geochemistry of mercury in source rocks, mineral deposits and spring deposits of the California Coast Ranges, USA

    USGS Publications Warehouse

    Smith, C.N.; Kesler, S.E.; Blum, J.D.; Rytuba, J.J.

    2008-01-01

    We present here the first study of the isotopic composition of mercury in rocks, ore deposits, and active spring deposits from the California Coast Ranges, a part of Earth's crust with unusually extensive evidence of mercury mobility and enrichment. The Franciscan Complex and Great Valley Sequence, which form the bedrock in the California Coast Ranges, are intruded and overlain by Tertiary volcanic rocks including the Clear Lake Volcanic Sequence. These rocks contain two types of mercury deposits, hot-spring deposits that form at shallow depths (< 300??m) and silica-carbonate deposits that extend to depths of 1000??m. Active springs and geothermal areas continue to precipitate Hg and Au and are modern analogues to the fossil hydrothermal systems preserved in the ore deposits. The Franciscan Complex and Great Valley Sequence contain clastic sedimentary rocks with higher concentrations of mercury than volcanic rocks of the Clear Lake Volcanic Field. Mean mercury isotopic compositions (??202Hg) for all three rock units are similar, although the range of values in Franciscan Complex rocks is greater than in either Great Valley or Clear Lake rocks. Hot spring and silica-carbonate mercury deposits have similar average mercury isotopic compositions that are indistinguishable from averages for the three rock units, although ??202Hg values for the mercury deposits have a greater variance than the country rocks. Precipitates from spring and geothermal waters in the area have similarly large variance and a mean ??202Hg value that is significantly lower than the ore deposits and rocks. These observations indicate that there is little or no isotopic fractionation (< ?? 0.5???) during release of mercury from its source rocks into hydrothermal solutions. Isotopic fractionation does appear to take place during transport and concentration of mercury in deposits, however, especially in their uppermost parts. Boiling of hydrothermal fluids, separation of a mercury-bearing CO2 vapor

  3. Rock Properties Model

    SciTech Connect

    C. Lum

    2004-09-16

    The purpose of this model report is to document the Rock Properties Model version 3.1 with regard to input data, model methods, assumptions, uncertainties and limitations of model results, and qualification status of the model. The report also documents the differences between the current and previous versions and validation of the model. The rock properties model provides mean matrix and lithophysae porosity, and the cross-correlated mean bulk density as direct input to the ''Saturated Zone Flow and Transport Model Abstraction'', MDL-NBS-HS-000021, REV 02 (BSC 2004 [DIRS 170042]). The constraints, caveats, and limitations associated with this model are discussed in Section 6.6 and 8.2. Model validation accomplished by corroboration with data not cited as direct input is discussed in Section 7. The revision of this model report was performed as part of activities being conducted under the ''Technical Work Plan for: The Integrated Site Model, Revision 05'' (BSC 2004 [DIRS 169635]). The purpose of this revision is to bring the report up to current procedural requirements and address the Regulatory Integration Team evaluation comments. The work plan describes the scope, objectives, tasks, methodology, and procedures for this process.

  4. Schiaparelli Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-403, 26 June 2003

    Some of the most important high resolution imaging results of the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) experiment center on discoveries about the presence and nature of the sedimentary rock record on Mars. This old meteor impact crater in northwestern Schiaparelli Basin exhibits a spectacular view of layered, sedimentary rock. The 2.3 kilometer (1.4 miles) wide crater may have once been completely filled with sediment; the material was later eroded to its present form. Dozens of layers of similar thickness and physical properties are now expressed in a wedding cake-like stack in the middle of the crater. Sunlight illuminating the scene from the left shows that the circle, or mesa top, at the middle of the crater stands higher than the other stair-stepped layers. The uniform physical properties and bedding of these layers might indicate that they were originally deposited in a lake (it is possible that the crater was at the bottom of a much larger lake, filling Schiaparelli Basin); alternatively, the layers were deposited by settling out of the atmosphere in a dry environment. This picture was acquired on June 3, 2003, and is located near 0.9oS, 346.2oW.

  5. Fossils, rocks, and time

    USGS Publications Warehouse

    Edwards, Lucy E.; Pojeta, John

    1999-01-01

    We study our Earth for many reasons: to find water to drink or oil to run our cars or coal to heat our homes, to know where to expect earthquakes or landslides or floods, and to try to understand our natural surroundings. Earth is constantly changing--nothing on its surface is truly permanent. Rocks that are now on top of a mountain may once have been at the bottom of the sea. Thus, to understand the world we live on, we must add the dimension of time. We must study Earth's history. When we talk about recorded history, time is measured in years, centuries, and tens of centuries. When we talk about Earth history, time is measured in millions and billions of years. Time is an everyday part of our lives. We keep track of time with a marvelous invention, the calendar, which is based on the movements of Earth in space. One spin of Earth on its axis is a day, and one trip around the Sun is a year. The modern calendar is a great achievement, developed over many thousands of years as theory and technology improved. People who study Earth's history also use a type of calendar, called the geologic time scale. It looks very different from the familiar calendar. In some ways, it is more like a book, and the rocks are its pages. Some of the pages are torn or missing, and the pages are not numbered, but geology gives us the tools to help us read this book.

  6. Fossils, rocks, and time

    USGS Publications Warehouse

    Edwards, Lucy E.; Pojeta, John

    1993-01-01

    We study out Earth for many reasons: to find water to drink or oil to run our cars or coal to heat our homes, to know where to expect earthquakes or landslides or floods, and to try to understand our natural surroundings. Earth is constantly changing--nothing on its surface is truly permanent. Rocks that are not on top of a mountain may once have been on the bottom of the sea. Thus, to understand the world we live on, we must add the dimension of time. We must study Earth's history. When we talk about recorded history, time is measured in years, centuries, and tens of centuries. When we talk about Earth history, time is measured in millions and billions of years. Time is an everyday part of our lives. We keep track of time with a marvelous invention, the calendar, which is based on the movements of the Earth in space. One spin of Earth on its axis is a day, and one trip around the sun is a year. The modern calendar is a great achievement, developed over many thousands of years as theory and technology improved. People who study Earth's history also use a type of calendar, called the geologic time scale. It looks very different from the familiar calendar. In some ways, it is more like a book, and the rocks are its pages. Some of the pages are torn or missing, and the pages are not numbered, but geology gives us the tools to help us read this book.

  7. Rocks as poroelastic composites

    SciTech Connect

    Berryman, J G

    1998-04-30

    In Biot's theory of poroelasticity, elastic materials contain connected voids or pores and these pores may be filled with fluids under pressure. The fluid pressure then couples to the mechanical effects of stress or strain applied externally to the solid matrix. Eshelby's formula for the response of a single ellipsoidal elastic inclusion in an elastic whole space to a strain imposed at infinity is a very well-known and important result in elasticity. Having a rigorous generalization of Eshelby's results valid for poroelasticity means that the hard part of Eshelby' work (in computing the elliptic integrals needed to evaluate the fourth-rank tensors for inclusions shaped like spheres, oblate and prolate spheroids, needles and disks) can be carried over from elasticity to poroelasticity - and also thermoelasticity - with only trivial modifications. Effective medium theories for poroelastic composites such as rocks can then be formulated easily by analogy to well-established methods used for elastic composites. An identity analogous to Eshelby's classic result has been derived [Physical Review Letters 79:1142-1145 (1997)] for use in these more complex and more realistic problems in rock mechanics analysis. Descriptions of the application of this result as the starting point for new methods of estimation are presented.

  8. A smart rock

    NASA Astrophysics Data System (ADS)

    Pressel, Phil

    2014-12-01

    This project was to design and build a protective weapon for a group of associations that believed in aliens and UFO's. They collected enough contributions from societies and individuals to be able to sponsor and totally fund the design, fabrication and testing of this equipment. The location of this facility is classified. It also eventually was redesigned by the Quartus Engineering Company for use at a major amusement park as a "shoot at targets facility." The challenge of this project was to design a "smart rock," namely an infrared bullet (the size of a gallon can of paint) that could be shot from the ground to intercept a UFO or any incoming suspicious item heading towards the earth. Some of the challenges to design this weapon were to feed cryogenic helium at 5 degrees Kelvin from an inair environment through a unique rotary coupling and air-vacuum seal while spinning the bullet at 1500 rpm and maintain its dynamic stability (wobble) about its spin axis to less than 10 micro-radians (2 arc seconds) while it operated in a vacuum. Precision optics monitored the dynamic motion of the "smart rock."

  9. Overview: Hard Rock Penetration

    SciTech Connect

    Dunn, J.C.

    1992-08-01

    The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.

  10. Overview - Hard Rock Penetration

    SciTech Connect

    Dunn, James C.

    1992-03-24

    The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling Organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.

  11. Overview: Hard Rock Penetration

    SciTech Connect

    Dunn, J.C.

    1992-01-01

    The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.

  12. Building The Bell Rock Lighthouse

    ERIC Educational Resources Information Center

    Shallcross, David C.

    2005-01-01

    Ever since the first mariners sailed off the east coast of Scotland the Bell Rock has claimed many vessels and countless lives. Also known as the Inch Cape Rocks they lie 18 km off the coast at Arbroath. Located near the mouth of the Firth of Forth and its important shipping ports these dangerous rocks cover an area some 440 m long and 90 m wide.…

  13. Mars Rock Formation Poses Mystery

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This sharp, close-up image taken by the microscopic imager on the Mars Exploration Rover Opportunity's instrument deployment device, or 'arm,' shows a rock target dubbed 'Robert E,' located on the rock outcrop at Meridiani Planum, Mars. Scientists are studying this area for clues about the rock outcrop's composition. This image measures 3 centimeters (1.2 inches) across and was taken on the 15th day of Opportunity's journey (Feb. 8, 2004).

  14. [Hearing disorders and rock music].

    PubMed

    Lindhardt, Bjarne Orskov

    2008-12-15

    Only few studies have investigated the frequency of hearing disorders in rock musicians. Performing rock music is apparently associated with a hearing loss in a fraction of musicians. Tinnitus and hyperacusis are more common among rock musicians than among the background population. It seems as if some sort of resistance against further hearing loss is developed over time. The use of ear protection devices have not been studied systematically but appears to be associated with diminished hearing loss.

  15. Geoelectrical Classification of Gypsum Rocks

    NASA Astrophysics Data System (ADS)

    Guinea, Ander; Playà, Elisabet; Rivero, Lluís; Himi, Mahjoub; Bosch, Ricard

    2010-12-01

    Gypsum rocks are widely exploited in the world as industrial minerals. The purity of the gypsum rocks (percentage in gypsum mineral in the whole rock) is a critical factor to evaluate the potential exploitability of a gypsum deposit. It is considered than purities higher than 80% in gypsum are required to be economically profitable. Gypsum deposits have been studied with geoelectrical methods; a direct relationship between the electrical resistivity values of the gypsum rocks and its lithological composition has been established, with the presence of lutites being the main controlling factor in the geoelectrical response of the deposit. This phenomenon has been quantified in the present study, by means of a combination of theoretical calculations, laboratory measurements and field data acquisition. Direct modelling has been performed; the data have been inverted to obtain the mean electrical resistivity of the models. The laboratory measurements have been obtained from artificial gypsum-clay mixture pills, and the electrical resistivity has been measured using a simple electrical circuit with direct current power supply. Finally, electrical resistivity tomography data have been acquired in different evaporite Tertiary basins located in North East Spain; the selected gypsum deposits have different gypsum compositions. The geoelectrical response of gypsum rocks has been determined by comparing the resistivity values obtained from theoretical models, laboratory tests and field examples. A geoelectrical classification of gypsum rocks defining three types of gypsum rocks has been elaborated: (a) Pure Gypsum Rocks (>75% of gypsum content), (b) Transitional Gypsum Rocks (75-55%), and (c) Lutites and Gypsum-rich Lutites (<55%). From the economic point of view, the Pure Gypsum Rocks, displaying a resistivity value of >800 ohm.m, can be exploited as industrial rocks. The methodology used could be applied in other geoelectrical rock studies, given that this relationship

  16. Petrology of the igneous rocks

    NASA Technical Reports Server (NTRS)

    Mccallum, I. S.

    1987-01-01

    Papers published during the 1983-1986 period on the petrology and geochemistry of igneous rocks are discussed, with emphasis on tectonic environment. Consideration is given to oceanic rocks, subdivided into divergent margin suites (mid-ocean ridge basalts, ridge-related seamounts, and back-arc basin basalts) and intraplate suites (oceanic island basalts and nonridge seamounts), and to igneous rocks formed at convergent margins (island arc and continental arc suites), subdivided into volcanic associations and plutonic associations. Other rock groups discussed include continental flood basalts, layered mafic intrusions, continental alkalic associations, komatiites, ophiolites, ash-flow tuffs, anorthosites, and mantle xenoliths.

  17. Thrust-ridge paleodepositional model for the Upper Freeport coal bed and associated clastic facies, Upper Potomac coal field, Appalachian Basin, U.S.A.

    USGS Publications Warehouse

    Belt, E.S.; Lyons, P.C.

    1990-01-01

    Two differential depositional sequences are recognized within a 37-m-thick lowermost section of the Conemaugh Group of Late Pennsylvanian (Westphalian D) age in the southern part of the Upper Potomac coal field (panhandle of Maryland and adjacent West Virginia). The first sequence is dominated by the Upper Freeport coal bed and zone (UF); the UF consists of a complex of interfingered thick coal beds and mudrocks. The UF underlies the entire 500 km2 study area (approximately 40 km in a NE-SW direction). The second sequence is dominated by medium- to coarse-grained sandstone and pebbly sandstone. They were deposited in channel belts that cut into and interfingered laterally with mudrock and fine- to medium-grained sandstone facies of floodbasin and crevasse-lobe origin. Thin lenticular coals occur in the second sequence. Nowhere in the study area does coarse-grained sandstone similar to the sandstone of the channel belts of the second sequence occur within the UF. However, 20 km north of the study area, coarse channel belts are found that are apparently synchronous with the UF (Lyons et al., 1984). The southeastern margin of the study are is bounded by the Allegheny Front. Between it and the North Mountain thrust (75 km to the southeast), lie at least eight other thrusts of unknown extent (Wilson, 1887). All these thrusts are oriented northwest; Devonian and older strata are exposed at the surface between the Allegheny Front and the North Mountain thrust. A blind-thrust ridge model is proposed to explain the relation of the two markedly depositional sequences to the thrusts that lie to the southeast of the Upper Potomac coal field. This model indicates that thrust ridges diverted coarse clastics from entering the swamp during a period when the thick Upper Freeport peat accumulated. Anticlinal thrust ridges and associated depressions are envisioned to have developed parallel to the Appalachian orogen during Middle and early Late Pennsylvanian time. A blind thrust

  18. Radiogenic heat production in sedimentary rocks of the Gulf of Mexico Basin, south Texas

    USGS Publications Warehouse

    McKenna, T.E.; Sharp, J.M.

    1998-01-01

    Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we calculate radiogenic heat production for Stuart City (Lower Cretaceous) limestones, Wilcox (Eocene) sandstones and mudrocks, and Frio (Oligocene) sandstones and mudrocks from south Texas. Heat production rates range from a low of 0.07 ?? 0.01 ??W/m3 in clean Stuart City limestones to 2.21 ?? 0.24??W/m3 in Frio mudrocks. Mean heat production rates for Wilcox sandstones, Frio sandstones, Wilcox mudrocks, and Frio mudrocks are 0.88, 1.19, 1.50, and 1.72 ??W/m3, respectively. In general, the mudrocks produce about 30-40% more heat than stratigraphically equivalent sandstones. Frio rocks produce about 15% more heat than Wilcox rocks per unit volume of clastic rock (sandstone/mudrock). A one-dimensional heat-conduction model indicates that this radiogenic heat source has a significant effect on subsurface temperatures. If a thermal model were calibrated to observed temperatures by optimizing basal heat-flow density and ignoring sediment heat production, the extrapolated present-day temperature of a deeply buried source rock would be overestimated.Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we

  19. Fan-delta and interdeltaic shoreline sediments of Middle Devonian Granite Wash and Keg River clastics, Red Earth field, north Alberta basin, Canada

    SciTech Connect

    Sabry, H.

    1989-03-01

    A detailed sedimentological investigation of over 4000 ft of core and 500 well logs of the Middle Devonian granite wash and Keg River clastics in the Red Earth field, North Alberta basin, Canada, has led to the recognition of a granite wash subaerial fan-delta system that is laterally continuous with a Keg River subaqueous delta component along an eastern shoreline of the ancestral Peace River arch. The subaerial fan delta includes alluvial fan facies, sheet wash and mud flows, and playa lakes. The subaqueous delta component includes lower shoreface, upper shoreface, beach-foreshore, eolian sand dunes, lagoon, washover sands, tidal channels and flats, and supratidal carbonates and anhydrites. Within this system, six mappable units are defined. A conceptual depositional model for the sequence depicts four main events. (1) Erosion of Peach River arch uplifted fault blocks, which produced coarse-grained fan-delta sediments in an adjacent fault-bounded margin. Subsequent fluvial reworking resulted in the deposition of thick, lenticular, wedge-shaped alluvial fans of granite wash. (2) Progradation of alluvial fans seaward into the Keg River Sea. (3) Transgression by Middle Devonian seas from the east, which reworked alluvial fans and led to deposition of discontinuous linear sand bodies represented by the Keg River regressive shoreline sediments. (4) Restriction of the sea by the Presqu'ile barrier reef to the north, which deposited evaporites of the Muskeg Formation over the whole sequence. Modern analog to this fan-delta system is the coastal fans of the Gulf of Aqaba, Red Sea. Red Earth field contains over 27 million bbl of recoverable oil, related to a combination structural-stratigraphic trap.

  20. The Chemical Signal of Clastic-biogenic Varves during the Last 2000 Years from Lake Nautajärvi (Southern Finland)

    NASA Astrophysics Data System (ADS)

    Kosonen, E.; Ojala, A. E.; Francus, P.; Kihlman, S.

    2010-12-01

    Annually laminated (varved) lake sediments provide high-resolution information on past environmental and limnological conditions. The study site, Lake Nautajärvi (24°41’E/61°48’N), is a small dimictic lake located in southern central Finland. Lake Nautajärvi forms and preserves clastic-biogenic varve sediments that are comprised of light (minerogenic) and dark (organic) couplets (approximately 0.6 mm thick). The minerogenic layer is deposited during spring when snow melt waters transport fine allogenic mineral matter from the catchment area into the lake. The organic layer is composed of authigenic organic matter and is deposited during summer, autumn and winter. Hence, the climatic factors (seasons, precipitation, snow and ice cover, lake productivity) have an affect on the varve structure, formation and chemical composition. The Lake Nautajärvi varve chronology extends up to 10 000 years from present day. The enhancement of X-ray fluorescence (XRF) instruments has opened up new applications for lacustrine and marine sediments. The ITRAX Core Scanner is a fast and non-destructive way to produce high-resolution (100 µm) elemental profiles. Elemental profiles can provide accurate information on annual and seasonal sedimentary fluctuation. The ITRAX chemical analysis was performed on epoxy impregnated sediment blocks that cover the last 2000 years. The µ-XRF chemical analysis (µ-XRF Mo tube with a 20 s acquisition time and step size of 100 µm) detected 24 elements of which Si, K, Ti, Ca, Cl, Mn and Fe showed the most relevant elemental profiles. Selected elemental signals (K, Ti, Ca, Mn, Cl) reveal two opposite trends that show similarities with X-ray densitometry based organic and minerogenic layer thicknesses. In this study, we combine XRF element profiles with the existing X-ray densitometry data and focus on interpreting the high-resolution elemental signals from Lake Nautajärvi over the last 2000 years.

  1. Application of advanced reservoir characterization, simulation, and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, West Texas (Delaware Basin). Technical progress report

    SciTech Connect

    Dutton, S.P.

    1996-04-30

    The objective of this project is to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost effective way to recover a higher percentage of the original oil in place through strategic placement of infill wells and geologically based field development. Project objectives are divided into two major phases. The objectives of the reservoir characterization phase of the project are to provide a detailed understanding of the architecture and heterogeneity of two fields, the Ford Geraldine unit and Ford West field, which produce from the Bell Canyon and Cherry Canyon Formations, respectively, of the Delaware Mountain Group and to compare Bell Canyon and Cherry Canyon reservoirs. Reservoir characterization will utilize 3-D seismic data, high-resolution sequence stratigraphy, subsurface field studies, outcrop characterization, and other techniques. One the reservoir-characterization study of both field is completed, a pilot area of approximately 1 mi{sup 2} in one of the fields will be chosen for reservoir simulation. The objectives of the implementation phase of the project are to: (1) apply the knowledge gained from reservoir characterization and simulation studies to increase recovery from the pilot area; (2) demonstrate that economically significant unrecovered oil remains in geologically resolvable untapped compartments; and (3) test the accuracy of reservoir characterization and flow simulation as predictive tools in resource preservation of mature fields. A geologically designed, enhanced recovery program (CO{sub 2} flood, waterflood, or polymer flood) and well-completion program will be developed, and one to three infill well will be drilled and cored. Technical progress is summarized for: geophysical characterization; reservoir characterization; outcrop characterization; and producibility problem characterization.

  2. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin)

    SciTech Connect

    Andrew G. Cole; George B. Asquith; Jose I. Guzman; Mark D. Barton; Mohammad A. Malik; Shirley P. Dutton; Sigrid J. Clift

    1998-04-01

    The objective of this Class III project is to demonstrate that detailed reservoir characterization of clastic reservoirs in basinal sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover more of the original oil in place by strategic infill-well placement and geologically based enhanced oil recovery. The study focused on the Ford Geraldine unit, which produces from the upper Bell Canyon Formation (Ramsey sandstone). Reservoirs in this and other Delaware Mountain Group fields have low producibility (average recovery <14 percent of the original oil in place) because of a high degree of vertical and lateral heterogeneity caused by depositional processes and post-depositional diagenetic modification. Outcrop analogs were studied to better interpret the depositional processes that formed the reservoirs at the Ford Geraldine unit and to determine the dimensions of reservoir sandstone bodies. Facies relationships and bedding architecture within a single genetic unit exposed in outcrop in Culberson County, Texas, suggest that the sandstones were deposited in a system of channels and levees with attached lobes that initially prograded basinward, aggraded, and then turned around and stepped back toward the shelf. Channel sandstones are 10 to 60 ft thick and 300 to 3,000 ft wide. The flanking levees have a wedge-shaped geometry and are composed of interbedded sandstone and siltstone; thickness varies from 3 to 20 ft and length from several hundred to several thousands of feet. The lobe sandstones are broad lens-shaped bodies; thicknesses range up to 30 ft with aspect ratios (width/thickness) of 100 to 10,000. Lobe sandstones may be interstratified with laminated siltstones.

  3. Relations of borehole resistivity to the horizontal hydraulic conductivity and dissolved-soils concentration in water of clastic coastal plain aquifers in the southeastern United States

    USGS Publications Warehouse

    Faye, Robert E.; Smith, Winston G.

    1994-01-01

    Aquifer bulk resistivity and grain-surface resistivity (inverse of grain-surface conductance) were tested as geoelectrical analogs to the horizontal hydraulic conductivity of clastic, freshwater aquifers in the Southeastern United States. Bulk resistivity was also tested as a geoelectrical analog for dissolved-solids concentrations in aquifer water. Bulk resistivity was defined as the average resistivity across a contributing interval measured by the long-normal (64-inch) or induction log. Grain-surface resistivity was empirically defined as the difference between aquifer bulk resistivity and aquifer water resistivity (computed from specific conductance). Sources of data were borehole geophysical logs and results of water-quality and aquifer-test analyses related to unconsolidated sands and clayey sands at more than a hundred sites in seven Southeastern States. Waterbearing units were composed of sediments ranging from the Late Cretaceous to middle Eocene. All bivariate data were related using the logarithmic regression model Y=AX B. Aquifer bulk resistivity and grain-surface resistivity were moderately correlated to horizontal hydraulic conductivity (70 and 72 percent correlation coefficients, respectively). Apparent formation factor, defined as the ratio of aquifer bulk resistivity to aquifer water resistivity, was shown to be poorly correlated with horizontal hydraulic conductivity (38 percent correlation coefficient). Aquifer bulk resistivity was shown to be highly correlated with dissolved-solids concentration and aquifer water resistivity (88 and 93 percent correlation coefficients, respectively). Regression models using bulk resistivity and aquifer water resistivity as independent variables were applied at four locations in South Carolina and Louisiana to predict dissolved-solids concentrations in aquifer water. Absolute mean error of prediction was 20 and 6 percent, respectively. A regression model using bulk resistivity to predict horizontal hydraulic

  4. Stratigraphy of lower to middle Paleozoic rocks of northern Nevada and the Antler orogeny

    USGS Publications Warehouse

    Ketner, Keith B.

    2013-01-01

    Commonly accepted concepts concerning the lower Paleozoic stratigraphy of northern Nevada are based on the assumption that the deep-water aspects of Ordovician to Devonian siliceous strata are due to their origin in a distant oceanic environment, and their presence where we find them is due to tectonic emplacement by the Roberts Mountains thrust. The concept adopted here is based on the assumption that their deep-water aspects are the result of sea-level rise in the Cambrian, and all of the Paleozoic strata in northern Nevada are indigenous to that area. The lower part of the Cambrian consists mainly of shallow-water cross-bedded sands derived from the craton. The upper part of the Cambrian, and part of the Ordovician, consists mainly of deep-water carbonate clastics carried by turbidity currents from the carbonate shelf in eastern Nevada, newly constructed as a result of sea-level rise. Ordovician to mid-Devonian strata are relatively deep-water siliceous deposits, which are the western facies assemblage. The basal contact of this assemblage on autochthonous Cambrian rocks is exposed in three mountain ranges and is clearly depositional in all three. The western facies assemblage can be divided into distinct stratigraphic units of regional extent. Many stratigraphic details can be explained simply by known changes in sea level. Upper Devonian to Mississippian strata are locally and westerly derived orogenic clastic beds deposited disconformably on the western facies assemblage. This disconformity, clearly exposed in 10 mountain ranges, indicates regional uplift and erosion of the western facies assemblage and absence of local deformation. The disconformity represents the Antler orogeny.

  5. Rock.XML - Towards a library of rock physics models

    NASA Astrophysics Data System (ADS)

    Jensen, Erling Hugo; Hauge, Ragnar; Ulvmoen, Marit; Johansen, Tor Arne; Drottning, Åsmund

    2016-08-01

    Rock physics modelling provides tools for correlating physical properties of rocks and their constituents to the geophysical observations we measure on a larger scale. Many different theoretical and empirical models exist, to cover the range of different types of rocks. However, upon reviewing these, we see that they are all built around a few main concepts. Based on this observation, we propose a format for digitally storing the specifications for rock physics models which we have named Rock.XML. It does not only contain data about the various constituents, but also the theories and how they are used to combine these building blocks to make a representative model for a particular rock. The format is based on the Extensible Markup Language XML, making it flexible enough to handle complex models as well as scalable towards extending it with new theories and models. This technology has great advantages as far as documenting and exchanging models in an unambiguous way between people and between software. Rock.XML can become a platform for creating a library of rock physics models; making them more accessible to everyone.

  6. Hydrocarbon potential of hydrocarbon source rocks of the New Siberian Islands, Russian Arctic

    NASA Astrophysics Data System (ADS)

    Gaedicke, Christoph; Sobolev, Peter; Franke, Dieter; Piepjohn, Karsten; Brandes, Christian; Kus, Jolanta; Scheeder, Georg

    2016-04-01

    The New Siberian Islands are bridging the Laptev Sea with the East Siberian Sea. The Laptev and East Siberian Seas cover large areas of the continental margin of northeastern Arctic Russia. The East Siberian Shelf encompassing an area of 935.000 km2 is still virtually unexplored and most of the geological models for this shelf are extrapolations of the geology of the New Siberian Islands, the Wrangel Island and the northeast Siberian landmass. Apart from few seismic reflection lines, airborne magnetic data were the primary means of deciphering the structural pattern of the East Siberian Shelf. The Laptev Shelf covers an area of about 66.000 km2 and occupies a shelf region, where the active mid-oceanic spreading ridge of the Eurasian Basin hits the slope of the continental margin. During the joint VSEGEI/BGR field expedition CASE 13 (Circum Arctic Structural Events) in summer 2011 we sampled outcrops from the New Siberian Archipelago including the De Long Islands. 102 samples were collected and the Upper Palaeozoic to Lower Cenozoic units are found to be punctuated by several organic-rich intervals. Lithology varies from continental dominated clastic sedimentary rocks with coal seams to shallow marine carbonates and deep marine black shales. Rock-Eval pyrolysis, gas chromatography/mass spectrometry and organic petrography studies were performed to estimate organic matter contents, composition, source, and thermal maturity. According to the results of our analyses, samples from several intervals may be regarded as potential petroleum source rocks. The Lower Devonian shales have the highest source rock potential of all Paleozoic units. Triassic samples have a good natural gas potential. Cretaceous and Cenozoic low-rank coals, lignites, and coal-bearing sandstones display some gas potential. The kerogen of type III (humic, gas-prone) dominates. Most of the samples (except some of Cretaceous and Paleogene age) reached the oil generation window.

  7. Meridiani Sedimentary Rocks

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-545, 15 November 2003

    Northern Sinus Meridiani is a region of vast exposures of layered, sedimentary rock. Buried within these layers are many filled impact craters. Erosion has re-exposed several formerly-buried craters in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image. Arrows 1 and 2 indicate craters that are still emerging from beneath layered material; arrow 3 indicates a crater that has been fully re-exposed. This image is located near 5.1oN, 2.7oW. The area shown is about 3 km (1.9 mi) wide and illuminated from the left/upper left.

  8. Rover, airbags, & surrounding rocks

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image of the Martian surface was taken by the Imager for Mars Pathfinder (IMP) before sunset on July 4 (Sol 1), the spacecraft's first day on Mars. The airbags have been partially retracted, and portions the petal holding the undeployed rover Sojourner can be seen at lower left. The rock in the center of the image may be a future target for chemical analysis. The soil in the foreground has been disturbed by the movement of the airbags as they retracted.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C.

  9. Rocks of low permeability

    NASA Astrophysics Data System (ADS)

    The 17th International Congress of the IAH (International Association of Hydrogeologists) will meet in Tucson, Ariz., January 7-10, 1985. The deadline for abstracts is March 1, 1984, and final papers are due October 15, 1984.The topic of the congress will be “Hydrogeology of Rocks of Low Permeability,” and speakers will include W. Back, J. F. Bredehoeft, G. de Marsily, J. E. Gale, P. Fritz, L. W. Gelhar, G. E. Grisak, C. W. Kreitler, M. R. Llamas, T. N. Narasimhan, I. Neretnieks, and E. P. Weeks. The congress will conclude with a panel discussion moderated by S. P. Neuman. Panelists include S. N. Davis, G. de Marsily, R. A. Freeze, P. A. Witherspoon, and I. Neretnieks.

  10. Rocks That Remember (Invited)

    NASA Astrophysics Data System (ADS)

    McEnroe, S. A.

    2009-12-01

    Parts of the continental crust preserve a magnetic memory that is billions of years old. Why do some rocks remember where they were born and others forget? Through time, continents travel over the world, but the memory preserved in some minerals remembers where they originated from, with a positioning system that can be envied even by modern technology. These magnetic mineral memory systems survived harsh environments, persevering in a magnetic field which changed in intensity and alternated in direction thousands of times, while also traveling the globe and possibly being subjected to enhanced temperatures. During all this, some crustal rocks retained most "magnetic sectors" in their "hard disk", and today create remanent magnetic anomalies reflecting the time and position of their initial remanent magnetization. Magnetic anomalies in planetary crusts are deviations from a global internal magnetic field. Measured over many length scales and at elevations ranging from near surface to satellites, crustal anomalies reflect the magnetic minerals, which respond to the changing planetary magnetic field. Anomalies are influenced by the geometry of the geological bodies, and by the magnetic and mineralogical properties of the constitutive rocks. Previously, magnetism of the continental crust has been completely described in terms of bulk ferrimagnetism of crustal minerals, and much of it due to induced magnetization. Even though remanent magnetization of the crust proved crucial for dating the ocean floor, and also is important for mineral exploration, the contribution of remanence to continental magnetic anomalies has been largely underestimated. In the course of studying remanent anomalies and the minerals responsible for them, a new interface-based remanence type, "lamellar magnetism", was discovered in rather common, slowly cooled, igneous and metamorphic rocks containing finely exsolved (10 microns to 1 nm) members of the rhombohedral hematite-ilmenite series

  11. Robotic Rock Classification

    NASA Technical Reports Server (NTRS)

    Hebert, Martial

    1999-01-01

    This report describes a three-month research program undertook jointly by the Robotics Institute at Carnegie Mellon University and Ames Research Center as part of the Ames' Joint Research Initiative (JRI.) The work was conducted at the Ames Research Center by Mr. Liam Pedersen, a graduate student in the CMU Ph.D. program in Robotics under the supervision Dr. Ted Roush at the Space Science Division of the Ames Research Center from May 15 1999 to August 15, 1999. Dr. Martial Hebert is Mr. Pedersen's research adviser at CMU and is Principal Investigator of this Grant. The goal of this project is to investigate and implement methods suitable for a robotic rover to autonomously identify rocks and minerals in its vicinity, and to statistically characterize the local geological environment. Although primary sensors for these tasks are a reflection spectrometer and color camera, the goal is to create a framework under which data from multiple sensors, and multiple readings on the same object, can be combined in a principled manner. Furthermore, it is envisioned that knowledge of the local area, either a priori or gathered by the robot, will be used to improve classification accuracy. The key results obtained during this project are: The continuation of the development of a rock classifier; development of theoretical statistical methods; development of methods for evaluating and selecting sensors; and experimentation with data mining techniques on the Ames spectral library. The results of this work are being applied at CMU, in particular in the context of the Winter 99 Antarctica expedition in which the classification techniques will be used on the Nomad robot. Conversely, the software developed based on those techniques will continue to be made available to NASA Ames and the data collected from the Nomad experiments will also be made available.

  12. Results and Discussion on Physical Property Calculation from Pore Microstructures of Carbonate Rocks

    NASA Astrophysics Data System (ADS)

    Lee, M.; Keehm, Y.

    2014-12-01

    In this paper, we report results and discussion on the physical properties estimation of carbonate rocks using pore microstructures. We obtained high-resolution 3D microstructures with different porosity-types (inter-particle, vuggy/moldic, and fracture) from the X-ray microtomography technique. We calculated permeability, electrical conductivity, and P-wave velocity using the Lattice-Boltzmann method and finite element methods. We also applied the pore-scale simulation techniques to different sub-blocks from the original 3D pore geometry (2,0003 voxels) to determine the heterogeneity of pore geometry. For the inter-particle porosity-type, the calculated transport properties (permeability and electrical conductivity) show very similar trends to clastic sediments. These relations can be modeled by common empirical relations such as Kozeny-Carman relation for porosity-permeability or Archie's equation for porosity-formation factor. For the vuggy or fracture porosity-type, it is difficult to determine any consistent relations; therefore we tried to build conceptual models with cracks or vugs to establish quantitative relations. On the other hand, P-wave velocity showed very little dependence on the porosity-types, due to high frame stiffness of carbonate rocks. Acknowledgements: This research was supported by the Basic Research Project of the Korea Institute of Geoscience and Mineral Resources (KIGAM) funded by the Ministry of Trade, Industry and Energy of Korea (GP2012-029).

  13. Influence of tectonic terranes adjacent to Precambrian Wyoming province of petroleum source and reservoir rock stratigraphy in northern Rocky Mountain region

    SciTech Connect

    Tonnsen, J.J.

    1984-07-01

    The perimeter of the Archean Precambrian Wyoming province can be generally defined. A Proterozoic suture belt separates the province from the Archean Superior province to the east. The western margin of the Precambrian rocks lies under the western Overthrust belt, but the Precambrian province extends at least as far west as southwest Montana and southeast Idaho. The province is bounded on the north and south by more regionally extensive Proterozoic mobile belts. In the northern belt, Archean rocks have been remobilized by Proterozoic tectonic events, but the southern belt does not appear to contain rocks as old as Archean. The tectonic response of these Precambrian terranes to cratonic and continental margin vertical and horizontal forces has exerted a profound influence on Phanerozoic sedimentation and stratigraphic facies distributions. Petroleum source rock and reservoir rock stratigraphy of the Northern Rocky Mountain region has been correlated with this structural history. In particular, the Devonian, Permian, and Jurassic sedimentation patterns can be shown to have been influenced by articulation among the different terranes comprising the ancient substructure. Depositional patterns in the Chester-Morrow carbonate and clastic sequence in the Central Montana trough are also related to this substructure. Further, a correlation between these tectonic terranes and the localization of regional hydrocarbon accumulations has been observed and has been useful in basin analyses for exploration planning.

  14. Bakhtin's Dialogics and Rock Lyrics.

    ERIC Educational Resources Information Center

    Knight, Jeff Parker

    Rock music is ideological both implicitly (in its intrinsic valuing of change, and resistance to authority, for instance), and explicitly (in political records from activist artists such as John Lennon and U2). The texts of the rock genre offer rhetorical experiences. A dialogic conception may help scholars to account for and describe the…

  15. The Rock Climbing Teaching Guide.

    ERIC Educational Resources Information Center

    Kudlas, John

    The product of 10 years of rock climbing instruction, this guide provides material from which an instructor can teach basic climbing concepts and safety skills as well as conduct a safe, enjoyable rock climbing class in a high school setting. It is designed for an instructor with limited experience in climbing; however, the need for teacher…

  16. Rocking Ratchets at High Frequencies

    NASA Astrophysics Data System (ADS)

    Reimann, Peter

    A pedagogical introduction to basic physical and mathematical concepts of stochastic modeling is given for the specific example of a rocking ratchet system. Perturbative methods are illustrated by deriving the leading order behavior of the particle current for asymptotically fast rocking forces.

  17. 'Mister Badger' Pushing Mars Rock

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Viking's soil sampler collector arm successfully pushed a rock on the surface of Mars during the afternoon of Friday, October 8. The irregular-shaped rock was pushed several inches by the Lander's collector arm, which displaced the rock to the left of its original position, leaving it cocked slightly upward. Photographs and other information verified the successful rock push. Photo at left shows the soil sampler's collector head pushing against the rock, named 'Mister Badger' by flight controllers. Photo at right shows the displaced rock and the depression whence it came. Part of the soil displacement was caused by the collector s backhoe. A soil sample will be taken from the site Monday night, October 11. It will then be delivered to Viking s organic chemistry instrument for a series of analyses during the next few weeks. The sample is being sought from beneath a rock because scientists believe that, if there are life forms on Mars, they may seek rocks as shelter from the Sun s intense ultraviolet radiation.

  18. Rockin' around the Rock Cycle

    ERIC Educational Resources Information Center

    Frack, Susan; Blanchard, Scott Alan

    2005-01-01

    In this activity students will simulate how sedimentary rocks can be changed into metamorphic rocks by intense pressure. The materials needed are two small pieces of white bread, one piece of wheat bread, and one piece of a dark bread (such as pumpernickel or dark rye) per student, two pieces of waxed paper, scissors, a ruler, and heavy books.…

  19. Further Reflections on Little Rock

    ERIC Educational Resources Information Center

    Allen, Danielle S.

    2007-01-01

    The famous photo of Hazel Bryan jeering at Elizabeth Eckford as a mob helped drive Elizabeth from Central High School in Little Rock, Arkansas, on September 4, 1957, compels meditation on the nature of democratic politics. This scene is commemorative of the Little Rock events where school segregation was rampant. The author believes that the photo…

  20. Rock Segmentation through Edge Regrouping

    NASA Technical Reports Server (NTRS)

    Burl, Michael

    2008-01-01

    Rockster is an algorithm that automatically identifies the locations and boundaries of rocks imaged by the rover hazard cameras (hazcams), navigation cameras (navcams), or panoramic cameras (pancams). The software uses edge detection and edge regrouping to identify closed contours that separate the rocks from the background.

  1. North-vergent thrust fault between Baltica and Laurentian affinity rocks in the frontal part of Romanzof orogen, NE Brooks Range, Alaska

    NASA Astrophysics Data System (ADS)

    Moore, T. E.; O'Sullivan, P. B.

    2012-12-01

    One of the most striking features of Arctic physiography is the long, linear Canadian Arctic margin of the Arctic Basin, which extends from the Lincoln Sea north of Greenland to the eastern Beaufort Sea and projects into northeastern Alaska. Among other ideas, this margin has been proposed to have developed by sinistral transform faulting in the Middle Devonian as a result of tectonic escape of terranes from the Caledonites (the so-called "Northwest Passage"). The faults on which the transform motion might have occurred, however, have not been recognized along the northern margin of North America. One candidate for such a fault is exposed at the southern boundary of the Sadlerochit Mountains province in the Tertiary frontal part of the NE Brooks Range. In the Plunge Creek area of the Arctic National Wildlife Refuge, a contact between rocks of Laurentian affinity and Baltica affinity is exposed on the back limb of a basement-involved map-scale thrust block formed by Brookian thrusting. The regional unconformity at the base of the Mississippian to Triassic Ellesmerian Sequence provides a near flat-lying datum that overlaps the contact between the pre-Mississippian tectonic units and demonstrates that it was not reactivated by Brookian thrusting. The Sadlerochit Mountains succession to the north of the contact consists of a Neoproterozoic and lower Paleozoic carbonate sequence that rests on metaclastic rocks that yield Grenville-Sveconorwegian (0.95-1.2 Ga) and other Mesoproterozoic detrital zircon U-Pb age populations similar to those reported from the northern parts of Baltica and eastern Greenland. In contrast, the Romanzof Mountains succession to the south consists of Neoproterozoic deep-marine clastic rocks (Neruokpuk Quartzite) and overlying lower Paleozoic chert and argillite. Detrital zircon U-Pb age populations from the Neruokpuk are very similar to those from Laurentian-derived clastic rocks in the Canadian margin of North America. Field relations show that

  2. Tracer tomography (in) rocks!

    NASA Astrophysics Data System (ADS)

    Somogyvári, Márk; Jalali, Mohammadreza; Jimenez Parras, Santos; Bayer, Peter

    2016-04-01

    Physical behavior of fractured aquifers is rigorously controlled by the presence of interconnected conductive fractures, as they represent the main pathways for flow and transport. Ideally, they are simulated as a discrete fracture network (DFN) in a model to capture the role of fracture system geometry, i.e. fracture length, height, and width (aperture/transmissivity). Such network may be constrained by prior geological information or direct data resources such as field mapping, borehole logging and geophysics. With the many geometric features, however, calibration of a DFN to measured data is challenging. This is especially the case when spatial properties of a fracture network need to be calibrated to flow and transport data. One way to increase the insight in a fractured rock is by combining the information from multiple field tests. In this study, a tomographic configuration that combines multiple tracer tests is suggested. These tests are conducted from a borehole with different injection levels that act as sources. In a downgradient borehole, the tracer is recorded at different levels or receivers, in order to maximize insight in the spatial heterogeneity of the rock. As tracer here we chose heat, and temperature breakthrough curves are recorded. The recorded tracer data is inverted using a novel stochastic trans-dimensional Markov Chain Monte Carlo procedure. An initial DFN solution is generated and sequentially modified given available geological information, such as expected fracture density, orientation, length distribution, spacing and persistency. During this sequential modification, the DFN evolves in a trans-dimensional inversion space through adding and/or deleting fracture segments. This stochastic inversion algorithm requires a large number of thousands of model runs to converge, and thus using a fast and robust forward model is essential to keep the calculation efficient. To reach this goal, an upwind coupled finite difference method is employed

  3. Analysis of Inflatable Rock Bolts

    NASA Astrophysics Data System (ADS)

    Li, Charlie C.

    2016-01-01

    An inflatable bolt is integrated in the rock mass through the friction and mechanical interlock at the bolt-rock interface. The pullout resistance of the inflatable bolt is determined by the contact stress at the interface. The contact stress is composed of two parts, termed the primary and secondary contact stresses. The former refers to the stress established during bolt installation and the latter is mobilized when the bolt tends to slip in the borehole owing to the roughness of the borehole surface. The existing analysis of the inflatable rock bolt does not appropriately describe the interaction between the bolt and the rock since the influence of the folded tongue of the bolt on the stiffness of the bolt and the elastic rebound of the bolt tube in the end of bolt installation are ignored. The interaction of the inflatable bolt with the rock is thoroughly analysed by taking into account the elastic displacements of the rock mass and the bolt tube during and after bolt installation in this article. The study aims to reveal the influence of the bolt tongue on the contact stress and the different anchoring mechanisms of the bolt in hard and soft rocks. A new solution to the primary contact stress is derived, which is more realistic than the existing one in describing the interaction between the bolt and the rock. The mechanism of the secondary contact stress is also discussed from the point of view of the mechanical behaviour of the asperities on the borehole surface. The analytical solutions are in agreement with both the laboratory and field pullout test results. The analysis reveals that the primary contact stress decreases with the Young's modulus of the rock mass and increases with the borehole diameter and installation pump pressure. The primary contact stress can be easily established in soft and weak rock but is low or zero in hard and strong rock. In soft and weak rock, the primary contact stress is crucially important for the anchorage of the bolt, while

  4. New approaches in the indirect quantification of thermal rock properties in sedimentary basins: the well-log perspective

    NASA Astrophysics Data System (ADS)

    Fuchs, Sven; Balling, Niels; Förster, Andrea

    2016-04-01

    Numerical temperature models generated for geodynamic studies as well as for geothermal energy solutions heavily depend on rock thermal properties. Best practice for the determination of those parameters is the measurement of rock samples in the laboratory. Given the necessity to enlarge databases of subsurface rock parameters beyond drill core measurements an approach for the indirect determination of these parameters is developed, for rocks as well a for geological formations. We present new and universally applicable prediction equations for thermal conductivity, thermal diffusivity and specific heat capacity in sedimentary rocks derived from data provided by standard geophysical well logs. The approach is based on a data set of synthetic sedimentary rocks (clastic rocks, carbonates and evaporates) composed of mineral assemblages with variable contents of 15 major rock-forming minerals and porosities varying between 0 and 30%. Petrophysical properties are assigned to both the rock-forming minerals and the pore-filling fluids. Using multivariate statistics, relationships then were explored between each thermal property and well-logged petrophysical parameters (density, sonic interval transit time, hydrogen index, volume fraction of shale and photoelectric absorption index) on a regression sub set of data (70% of data) (Fuchs et al., 2015). Prediction quality was quantified on the remaining test sub set (30% of data). The combination of three to five well-log parameters results in predictions on the order of <15% for thermal conductivity and thermal diffusivity, and of <10% for specific heat capacity. Comparison of predicted and benchmark laboratory thermal conductivity from deep boreholes of the Norwegian-Danish Basin, the North German Basin, and the Molasse Basin results in 3 to 5% larger uncertainties with regard to the test data set. With regard to temperature models, the use of calculated TC borehole profiles approximate measured temperature logs with an

  5. Geophysical log responses and their correlation with bed-to-bed stress contrasts in Paleozoic rocks, Appalachian Plateau, New York

    NASA Astrophysics Data System (ADS)

    Plumb, Richard A.; Evans, Keith F.; Engelder, Terry

    1991-08-01

    A 1-km profile of in situ stress and geophysical log data was acquired in the Wilkins well to study the relationship between rock properties and in situ stress contrasts. The Wilkins well penetrates Devonian clastic rocks on the Appalachian Plateau near the town of South Canisteo, New York. Open hole hydraulic fracture stress measurements were made in stratigraphic sequences where geophysical logs indicated significant bed-to-bed variations in elastic and lithologic properties. Analysis of stress magnitudes and interval-averaged geophysical data shows that principal horizontal stress magnitudes correlate directly with elastic stiffness and inversely with clay content. A similar relation is found for older Paleozoic strata penetrated by a well at Auburn, New York. Correlations between stress magnitude and geophysical properties observed in the Wilkins and Auburn wells provide strong evidence that bed to bed stress variations arise from a uniform ENE-WSW directed strain acting on beds of different Young's modulus rather than from variations in rock shear strength. Because of their high Young's modulus, sandstones, siltstones, and limestones in the northern Appalachian Basin are likely to be stronger barriers to hydraulic fracture propagation than shales. Porosity logs in the Wilkins well show that the large decrease in horizontal stress found at the base of the Rhine street Formation occurs where shales are less compacted. The correlation with undercompaction is consistent with a paleo-overpressure drainage mechanism as the cause for the stress decrease.

  6. The Influence of the De-Icing Salt on the Deterioration of Rock Materials Used in Monumental Buildings

    NASA Astrophysics Data System (ADS)

    Kłopotowska, Agnieszka Katarzyna; Łukaszewski, Paweł

    2013-09-01

    The de-icing salt has been used for decades to increase safety on the roads and sidewalks. In Poland, mainly the sodium chloride is used in order to maintain the roads in good condition during winter. Like other salts used for surface de-icing, it depresses the freezing point to lower temperatures and has an additional thermal effect by an exothermic reaction. However, this salt causes the accumulation of chlorides in the walls and stone buildings contributing to the deterioration of these facilities. The paper addresses the issue of the influence of salt solutions on the structure and geomechanical properties of rocks at negative temperatures. The study was conducted on the basis of cyclic tests which simulate complex action of both the negative temperature and the salty environment. The conditions for the tests were chosen so as to reflect the actual conditions of the winter in Poland. During the tests, the longitudinal wave propagation velocity, changes in weights of the samples as well as visual changes were recorded which allowed continuous tracking of occurring changes. At the end of the tests, the rock samples were subjected to uniaxial compressive tests. For this purpose, four lithological types were chosen, representing the sedimentary rocks: clastic and carbonate, widely used in stone constructions.

  7. Sorted clastic stripes, lobes and associated gullies in high-latitude craters on Mars: Landforms indicative of very recent, polycyclic ground-ice thaw and liquid flows

    NASA Astrophysics Data System (ADS)

    Gallagher, C.; Balme, M. R.; Conway, S. J.; Grindrod, P. M.

    2011-01-01

    Self-organised patterns of stone stripes, polygons, circles and clastic solifluction lobes form by the sorting of clasts from fine-grained sediments in freeze-thaw cycles. We present new High Resolution Imaging Science Experiment (HiRISE) images of Mars which demonstrate that the slopes of high-latitude craters, including Heimdal crater - just 25 km east of the Phoenix Landing Site - are patterned by all of these landforms. The order of magnitude improvement in imaging data resolution afforded by HiRISE over previous datasets allows not only the reliable identification of these periglacial landforms but also shows that high-latitude fluviatile gullies both pre- and post-date periglacial patterned ground in several high-latitude settings on Mars. Because thaw is inherent to the sorting processes that create these periglacial landforms, and from the association of this landform assemblage with fluviatile gullies, we infer the action of liquid water in a fluvio-periglacial context. We conclude that these observations are evidence of the protracted, widespread action of thaw liquids on and within the martian regolith. Moreover, the size frequency statistics of superposed impact craters demonstrate that this freeze-thaw environment is, at least in Heimdal crater, less than a few million years old. Although the current martian climate does not favour prolonged thaw of water ice, observations of possible liquid droplets on the strut of the Phoenix Lander may imply significant freezing point depression of liquids sourced in the regolith, probably driven by the presence of perchlorates in the soil. Because perchlorates have eutectic temperatures below 240 K and can remain liquid at temperatures far below the freezing point of water we speculate that freeze-thaw involving perchlorate brines provides an alternative "low-temperature" hypothesis to the freeze-thaw of more pure water ice and might drive significant geomorphological work in some areas of Mars. Considering the

  8. Shotgun cartridge rock breaker

    DOEpatents

    Ruzzi, Peter L.; Morrell, Roger J.

    1995-01-01

    A rock breaker uses shotgun cartridges or other firearm ammunition as the explosive charge at the bottom of a drilled borehole. The breaker includes a heavy steel rod or bar, a gun with a firing chamber for the ammunition which screws onto the rod, a long firing pin running through a central passage in the rod, and a firing trigger mechanism at the external end of the bar which strikes the firing pin to fire the cartridge within the borehole. A tubular sleeve surround the main body of the rod and includes slits the end to allow it to expand. The rod has a conical taper at the internal end against which the end of the sleeve expands when the sleeve is forced along the rod toward the taper by a nut threaded onto the external end of the rod. As the sleeve end expands, it pushes against the borehole and holds the explosive gasses within, and also prevents the breaker from flying out of the borehole. The trigger mechanism includes a hammer with a slot and a hole for accepting a drawbar or drawpin which, when pulled by a long cord, allows the cartridge to be fired from a remote location.

  9. Uranium series, volcanic rocks

    USGS Publications Warehouse

    Vazquez, Jorge A.

    2014-01-01

    Application of U-series dating to volcanic rocks provides unique and valuable information about the absolute timing of crystallization and differentiation of magmas prior to eruption. The 238U–230Th and 230Th-226Ra methods are the most commonly employed for dating the crystallization of mafic to silicic magmas that erupt at volcanoes. Dates derived from the U–Th and Ra–Th methods reflect crystallization because diffusion of these elements at magmatic temperatures is sluggish (Cherniak 2010) and diffusive re-equilibration is insignificant over the timescales (less than or equal to 10^5 years) typically associated with pre-eruptive storage of nearly all magma compositions (Cooper and Reid 2008). Other dating methods based on elements that diffuse rapidly at magmatic temperatures, such as the 40Ar/39Ar and (U–Th)/He methods, yield dates for the cooling of magma at the time of eruption. Disequilibrium of some short-lived daughters of the uranium series such as 210Po may be fractionated by saturation of a volatile phase and can be employed to date magmatic gas loss that is synchronous with volcanic eruption (e.g., Rubin et al. 1994).

  10. Prominent rocks - 3D

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Many prominent rocks near the Sagan Memorial Station are featured in this image, taken in stereo by the Imager for Mars Pathfinder (IMP) on Sol 3. 3D glasses are necessary to identify surface detail. Wedge is at lower left; Shark, Half-Dome, and Pumpkin are at center. Flat Top, about four inches high, is at lower right. The horizon in the distance is one to two kilometers away.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

    Click below to see the left and right views individually. [figure removed for brevity, see original site] Left [figure removed for brevity, see original site] Right

  11. Source rock potential in Pakistan

    SciTech Connect

    Raza, H.A. )

    1991-03-01

    Pakistan contains two sedimentary basins: Indus in the east and Balochistan in the west. The Indus basin has received sediments from precambrian until Recent, albeit with breaks. It has been producing hydrocarbons since 1914 from three main producing regions, namely, the Potwar, Sulaisman, and Kirthar. In the Potwar, oil has been discovered in Cambrian, Permian, Jurassic, and Tertiary rocks. Potential source rocks are identified in Infra-Cambrian, Permian, Paleocene, and Eocene successions, but Paleocene/Eocene Patala Formation seems to be the main source of most of the oil. In the Sulaiman, gas has been found in Cretaceous and Tertiary; condensate in Cretaceous rocks. Potential source rocks are indicated in Cretaceous, Paleocene, and Eocene successions. The Sembar Formation of Early Cretaceous age appears to be the source of gas. In the Kirthar, oil and gas have been discovered in Cretaceous and gas has been discovered in paleocene and Eocene rocks. Potential source rocks are identified in Kirthar and Ghazij formations of Eocene age in the western part. However, in the easter oil- and gas-producing Badin platform area, Union Texas has recognized the Sembar Formation of Early Cretaceous age as the only source of Cretaceous oil and gas. The Balochistan basin is part of an Early Tertiary arc-trench system. The basin is inadequately explored, and there is no oil or gas discovery so far. However, potential source rocks have been identified in Eocene, Oligocene, Miocene, and Pliocene successions based on geochemical analysis of surface samples. Mud volcanoes are present.

  12. Rock Dusting Leaves 'Mickey Mouse' Mark

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image taken by the navigation camera on the Mars Exploration Rover Spirit shows the rock dubbed 'Humphrey' and the circular areas on the rock that were wiped off by the rover. The rover used a brush on its rock abrasion tool to clean these spots before examining them with its miniature thermal emission spectrometer. Later, the rover drilled into the rock with its rock abrasion tool, exposing fresh rock underneath.

  13. Rock River Geographic Information System: ROCK-GIS (User Manual)

    DTIC Science & Technology

    2004-04-01

    Rock River GIS application was created using Environmental Systems Research Institute (ESRI) ArcGIS8.X software and Microsoft’s Visual Basic for Applications (VBA), which is included with ArcGIS8.X products.

  14. Space Weathering of Lunar Rocks

    NASA Technical Reports Server (NTRS)

    Noble, S. K.; Keller, L. P.; Christoffersen, R.; Rahman, Z.

    2012-01-01

    All materials exposed at the lunar surface undergo space weathering processes. On the Moon, boulders make up only a small percentage of the exposed surface, and areas where such rocks are exposed, like central peaks, are often among the least space weathered regions identified from remote sensing data. Yet space weathered surfaces (patina) are relatively common on returned rock samples, some of which directly sample the surface of larger boulders. Because, as witness plates to lunar space weathering, rocks and boulders experience longer exposure times compared to lunar soil grains, they allow us to develop a deeper perspective on the relative importance of various weathering processes as a function of time.

  15. Astronomy and Rock Art Studies

    NASA Astrophysics Data System (ADS)

    Murray, William Breen

    Rock art is often used as evidence for the earliest phases of prehistoric celestial knowledge and sky observation. Like the sky, rock art is a global phenomenon and it is also one of the earliest manifestations of human cognitive awareness. Similarities in iconography and visual context may provide evidence of sky-watching activity, and in some cases, ethnographic analogies, ethnohistoric documentation, and surviving archaeological evidence may confirm that these activities were related to rock art production. Nevertheless, the problem of random matches makes proofs of intentional relation more complicated. Probabilities are measured differently in archaeology and astronomy and can sometimes lead to ambiguous or contradictory conclusions.

  16. Multiverso: Rock'n'Astronomy

    NASA Astrophysics Data System (ADS)

    Caballero, J. A.

    2012-05-01

    In the last few years, there have been several projects involving astronomy and classical music. But have a rock band ever appeared at a science conference or an astronomer at a rock concert? We present a project, Multiverso, in which we mix rock and astronomy, together with poetry and video art (Caballero, 2010). The project started in late 2009 and has already reached tens of thousands people in Spain through the release of an album, several concert-talks, television, radio, newspapers and the internet.

  17. Mineral Detector for Igneous Rocks

    NASA Astrophysics Data System (ADS)

    Ishikawa, S. T.; Hart, S. D.; Gulick, V. C.

    2010-12-01

    We present a Raman spectral analysis tool that uses machine learning algorithms to classify pure minerals in igneous rocks. Experiments show greater than 90% accuracy classifying a test set of pure minerals against a database of similar reference minerals using an artificial neural network. Efforts are currently underway to improve this tool for use as a mineral detector in rock samples, an important milestone toward autonomously classifying rocks based on spectral, and previous imaging work. Although pure mineral classification has been widely successful, applying the same methods to rocks is difficult because the spectra may represent a combination of multiple, and often competing, mineral signatures. In such cases some minerals may appear with more intensity than others resulting in masking of weaker minerals. Furthermore, with our particular spectrometer (852 nm excitation, ~50 micron spot size), minerals such as potassium feldspar fluoresce, both obscuring its characteristic Raman features and suppressing those of weaker minerals. For example, plagioclase and quartz, two key minerals for determining the composition of igneous rocks, are often hidden by minerals such as potassium feldspar and pyroxene, and are consequently underrepresented in the spectral analysis. These technicalities tend to skew the perceived composition of a rock from its actual composition. Despite these obstacles, an experiment involving a training set of 26 minerals (plagioclase, potassium feldspar, pyroxene, olivine, quartz) and a test set of 57 igneous rocks (basalt, gabbro, andesite, diorite, dacite, granodiorite, rhyolite, granite) shows that generalizations derived from their spectral data are consistent with expected trends: as rock composition goes from felsic to mafic there is a marked increase in the detection of minerals such as plagioclase and pyroxene along with a decrease in the detection of minerals such as quartz and potassium feldspar. The results suggest that phaneritic

  18. Dynamics of rock varnish formation

    SciTech Connect

    Raymond, R. Jr.; Reneau, S.L.; Guthrie, G.D. Jr.; Bish, D.L.; Harrington, C.D.

    1991-01-01

    Our studies of rock varnish from the southwestern United States suggest that the Mn-phase in rock varnish has neither the chemistry nor the crystal structure of birnessite. Rather, the Mn-rich phase is non-crystalline and contains Ba, Ca, Fe, Al, and P. Unknowns concerning the formation of this non-crystalline Mn phase must be resolved before researchers are able to define chemical parameters of rock varnish formation based upon conditions of formation of the Mn phase. 6 refs., 9 figs.

  19. Applicability of failure criteria and empirical relations of mechanical rock properties from outcrop analogue samples for wellbore stability analyses

    NASA Astrophysics Data System (ADS)

    Reyer, D.; Philipp, S. L.

    2013-12-01

    Knowledge of failure criteria, Young's modulus and uniaxial and tensile strengths, are important to avoid borehole instabilities and adapt the drilling plan on rock mechanical conditions. By this means, a considerable reduction of the total drilling costs can be achieved. This is desirable to enlarge the profit margin of geothermal projects which is rather small compared with hydrocarbon projects. Because core material is rare we aim at predicting in situ rock properties from outcrop analogue samples which are easy and cheap to provide. The comparability of properties determined from analogue samples with samples from depths is analysed by performing conventional triaxial tests, uniaxial compressive strength tests and Brazilian tests of both quarry and equivalent core samples. Equivalent means that the quarry sample is of the same stratigraphic age and of comparable sedimentary facies and composition as the associated core sample. We determined the parameters uniaxial compressive strength (UCS), Young's modulus, and tensile strength for 35 rock samples from quarries and 14 equivalent core samples from the North German Basin. A subgroup of these samples, consisting of one volcanic rock sample, three sandstone and three carbonate samples, was used for triaxial tests. In all cases, comparability of core samples with quarry samples is evaluated using thin section analyses. For UCS versus Young's modulus and tensile strengths, linear- and non-linear regression analyses were performed. We repeat regression separately for clastic rock samples or carbonate rock samples only as well as for quarry samples or core samples only. Empirical relations have high statistical significance and properties of core samples lie within 90% prediction bands of developed regression functions of quarry samples. With triaxial tests we determined linearized Mohr-Coulomb failure criteria, expressed in both principal stresses and shear and normal stresses, for quarry samples. Comparison with

  20. Fluid and rock interaction in permeable volcanic rock

    SciTech Connect

    Lindley, J.I.

    1985-02-01

    Four types of interrelated changes -geochemical, mineralogic, isotopic, and physical - occur in Oligocene volcanic units of the Mogollon-Datil volcanic field, New Mexico. These changes resulted from the operation of a geothermal system that, through fluid-rock interaction, affected 5 rhyolite ash-flow tuffs and an intercalated basaltic andesite lava flow causing a potassium metasomatism type of alteration. (1) Previous studies have shown enrichment of rocks in K/sub 2/O as much as 130% of their original values at the expense of Na/sub 2/O and CaO with an accompanying increase in Rb and decreases in MgO and Sr. (2) X-ray diffraction results of this study show that phenocrystic plagioclase and groundmass feldspar have been replaced with pure potassium feldspar and quartz in altered rock. Phenocrystic potassium feldspar, biotite, and quartz are unaffected. Pyroxene in basaltic andesite is replaced by iron oxide. (3) delta/sup 18/O increases for rhyolitic units from values of 8-10 permil, typical of unaltered rock, to 13-15 permil, typical of altered rock. Basaltic andesite, however, shows opposite behavior with a delta/sup 18/ of 9 permil in unaltered rock and 6 permit in altered. (4) Alteration results in a density decrease. SEM revealed that replacement of plagioclase by fine-grained quartz and potassium feldspar is not a volume for volume replacement. Secondary porosity is created in the volcanics by the chaotic arrangement of secondary crystals.

  1. Anthropic Rock: a brief history

    NASA Astrophysics Data System (ADS)

    Cathcart, R. B.

    2011-03-01

    Stone tool-making is a reductive process. Synthetic rock manufacturing, preeminently an additive process, will not for-ever be confined to only the Earth-biosphere. This brief focuses on humanity's ancient past, hodiernal and possible future even more massive than present-day creation of artificial rocks within our exploitable Solar System. It is mostly Earth-centric account that expands the factual generalities underlying the unique non-copyrighted systemic technogenic rock classification first publicly presented (to the American Geological Society) during 2001, by its sole intellectual innovator, James Ross Underwood, Jr. His pioneering, unique exposition of an organization of this ever-increasingly important aspect of the Anthropic Rock story, spatially expansive material lithification, here is given an amplified discussion for the broader geo and space science social group-purpose of encouragement of a completer 21st Century treatment of Underwood's explicative subject-chart (Fig. 2).

  2. ROCK DEFORMATION. Final Progress Report

    SciTech Connect

    2002-05-24

    The Gordon Research Conference (GRC) on ROCK DEFORMATION was held at II Ciocco from 5/19/02 thru 5/24/02. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.

  3. City Rocks and National Standards.

    ERIC Educational Resources Information Center

    Becker, Martin; Slattery, William; Finegan-Stoll, Colleen

    1998-01-01

    Presents a weeklong earth science module that allows students to explore the relationships between natural and manufactured materials. Relates rocks and minerals in the earth science curriculum to observations students make in their urban and suburban travels. (DDR)

  4. The Rock Your Students Dig.

    ERIC Educational Resources Information Center

    McCombs, John P.

    1990-01-01

    Described is a field trip in which eighth grade earth science students map the rock types located on the side of a mountain. Pretrip preparation, equipment, procedures, and posttrip analysis are discussed. (CW)

  5. High resolution study of petroleum source rock variation, Lower Cretaceous (Hauterivian and Barremian) of Mikkelsen Bay, North Slope, Alaska

    USGS Publications Warehouse

    Keller, Margaret A.; Macquaker, Joe H.S.; Lillis, Paul G.

    2001-01-01

    Open File Report 01-480 was designed as a large format poster for the Annual Meeting of the American Association of Petroleum Geologists and the Society for Sedimentary Geology in Denver Colorado in June 2001. It is reproduced here in digital format to make widely available some unique images of mudstones. The images include description, interpretation, and Rock-Eval data that resulted from a high-resolution study of petroleum source rock variation of the Lower Cretaceous succession of the Mobil-Phillips Mikkelsen Bay State #1 well on the North Slope of Alaska. Our mudstone samples with Rock-Eval data plus color images are significant because they come from one of the few continuously cored and complete intervals of the Lower Cretaceous succession on the North Slope. This succession, which is rarely preserved in outcrop and very rarely cored in the subsurface, is considered to include important petroleum source rocks that have not previously been described nor explained Another reason these images are unique is that the lithofacies variability within mudstone dominated successions is relatively poorly known in comparison with that observed in coarser clastic and carbonate successions. They are also among the first published scans of thin sections of mudstone, and are of excellent quality because the sections are well made, cut perpendicular to bedding, and unusually thin, 20 microns. For each of 15 samples, we show a thin section scan (cm scale) and an optical photomicrograph (mm scale) that illustrates the variability present. Several backscattered SEM images are also shown. Rock-Eval data for the samples can be compared with the textures and mineralogy present by correlating sample numbers and core depth.

  6. Uranium enrichment in lacustrine oil source rocks of the Chang 7 member of the Yanchang Formation, Erdos Basin, China

    NASA Astrophysics Data System (ADS)

    Yang, Hua; Zhang, Wenzheng; Wu, Kai; Li, Shanpeng; Peng, Ping'an; Qin, Yan

    2010-09-01

    The oil source rocks of the Chang 7 member of the Yanchang Formation in the Erdos Basin were deposited during maximum lake extension during the Late Triassic and show a remarkable positive uranium anomaly, with an average uranium content as high as 51.1 μg/g. Uranium is enriched together with organic matter and elements such as Fe, S, Cu, V and Mo in the rocks. The detailed biological markers determined in the Chang 7 member indicate that the lake water column was oxidizing during deposition of the Chang 7 member. However, redox indicators for sediments such as S 2- content, V/Sc and V/(V + Ni) ratios demonstrate that it was a typical anoxic diagenetic setting. The contrasted redox conditions between the water column and the sediment with a very high content of organic matter provided favorable physical and chemical conditions for syngenetic uranium enrichment in the oil source rocks of the Chang 7 member. Possible uranium sources may be the extensive U-rich volcanic ash that resulted from contemporaneous volcanic eruption and uranium material transported by hydrothermal conduits into the basin. The uranium from terrestrial clastics was unlike because uranium concentration was not higher in the margin area of basin where the terrestrial material input was high. As indicated by correlative analysis, the oil source rocks of the Chang 7 member show high gamma-ray values for radioactive well log data that reflect a positive uranium anomaly and are characterized by high resistance, low electric potential and low density. As a result, well log data can be used to identify positive uranium anomalies and spatial distribution of the oil source rocks in the Erdos Basin. The estimation of the total uranium reserves in the Chang 7 member attain 0.8 × 10 8 t.

  7. Sinkhole susceptibility in carbonate rocks of the Apulian karst (southern Italy)

    NASA Astrophysics Data System (ADS)

    Di Santo, Antonio; Fazio, Nunzio L.; Fiore, Antonio; Lollino, Piernicola; Luisi, Michele; Miccoli, Maria N.; Pagliarulo, Rosa; Parise, Mario; Perrotti, Michele; Pisano, Luca; Spalluto, Luigi; Vennari, Carmela; Vessia, Giovanna

    2016-04-01

    Apulia region, the foreland of the southern Italian Apennines, is made up of a 6-7 km-thick succession of Mesozoic shallow-water limestones and dolostones, locally covered by thin and discontinuous Tertiary and Quaternary carbonate and clastic deposits. Due to their long subaerial exposure, the Mesozoic carbonate bedrock recorded the development in the subsurface of a dense network of karst cavities, mostly controlled by tectonic discontinuities. As a result, a strong susceptibility to natural sinkholes has to be recorded in Apulia. In addition, the possibility of occurrence of other problems related to the high number of man-made cavities has to be added in the region. A great variety of different typologies of artificial cavities (mostly excavated in the Plio-Pleistocene soft calcarenites) is actually present, including underground quarries, worship sites, oil mills, civilian settlements, etc. Overall, 2200 natural and 1200 artificial cavities, respectively, have been so far surveyed in Apulia. Following the urban development in the last century in Apulia, many of these cavities lie nowadays below densely populated neighborhoods, roads or communication routes. These conditions are at the origin of the main geomorphological hazard for the human society in Apulia, which requires a careful evaluation, aimed at protecting and safeguarding the human life, and at providing the necessary information for a correct land use planning and management. The importance of the sinkhole hazard is further testified by the worrying increase in the number of events during the last 5-6 years. In response to these situations, joint research activities were started by the Institute of Research for Hydrological Protection of the National Research Council (CNR-IRPI) and the Basin Authority of Apulia, aimed at several goals, that include (but are not limited to) the collection of information on natural and anthropogenic sinkholes in Apulia, the implementation of numerical analyses for

  8. Rock Mass Persistence. Executive Summary.

    DTIC Science & Technology

    1986-02-01

    Apertures 3.4 Geometry and Assumptions for Analysis of Slope in Jointed Rock 3.5 Deformation of Rock Mass after Excavation without Flow 3.6 Water ...open joint measured perpendicularly to joint walls (only ioints filled with air or water are considered open, while 3oints containing filler between...geometry models whith a suitable model representing flow in jointed media one can determine the hydraulic performance of such media. The flow of water

  9. Rock expansion caused by ultrasound

    NASA Astrophysics Data System (ADS)

    Hedberg, C.; Gray, A.

    2013-12-01

    It has during many years been reported that materials' elastic modulus decrease when exposed to influences like mechanical impacts, ultrasound, magnetic fields, electricity and even humidity. Non-perfect atomic structures like rocks, concrete, or damaged metals exhibit a larger effect. This softening has most often been recorded by wave resonance measurements. The motion towards equilibrium is slow - often taking hours or days, which is why the effect is called Slow Dynamics [1]. The question had been raised, if a material expansion also occurs. 'The most fundamental parameter to consider is the volume expansion predicted to occur when positive hole charge carriers become activated, causing a decrease of the electron density in the O2- sublattice of the rock-forming minerals. This decrease of electron density should affect essentially all physical parameters, including the volume.' [2]. A new type of configuration has measured expansion of a rock subjected to ultrasound. A PZT was used as a pressure sensor while the combined thickness of the rock sample and the PZT sensor was held fixed. The expansion increased the stress in both the rock and the PZT, which gave an out-put voltage from the PZT. Knowing its material properties then made it possible to calculate the rock expansion. The equivalent strain caused by the ultrasound was approximately 3 x 10-5. The temperature was monitored and accounted for during the tests and for the maximum expansion the increase was 0.7 C, which means the expansion is at least to some degree caused by heating of the material by the ultrasound. The fraction of bonds activated by ultrasound was estimated to be around 10-5. References: [1] Guyer, R.A., Johnson, P.A.: Nonlinear Mesoscopic Elasticity: The Complex Behaviour of Rocks, Soils, Concrete. Wiley-VCH 2009 [2] M.M. Freund, F.F. Freund, Manipulating the Toughness of Rocks through Electric Potentials, Final Report CIF 2011 Award NNX11AJ84A, NAS Ames 2012.

  10. Observations and Rock Analyses in a Kumano Mud Volcano in Nankai Accretionary Prism

    NASA Astrophysics Data System (ADS)

    Morita, S.; Aoike, K.; Sawada, T.; Ashi, J.; Gulick, S. P.; Flemings, P. B.; Kuramoto, S.; Saito, S.; Mikada, H.; Kinoshita, M.

    2002-12-01

    Kumano Basin is a forearc basin on the eastern Nankai Accretionary Prism off southwest Japan. Recent bathymetric survey showed existence of small knolls in the Kumano Basin. Submersible and ROV dives, sidescan sonar and deep-towed camera investigations revealed so far that at least five of the small knolls are mud volcanoes erupted on the Kumano Basin floor. In June and August, 2002, Dive 677 and 681 by submersible SHINKAI 6500 (YK02-02: R/V Yokosuka) and Dive 267 by ROV KAIKO (KR02-10: R/V Kairei) were performed in one of the mud volcanoes, Kumano Knoll No.4, which is 100 m high and 800 m in diameter at the foot of the knoll. The knoll has a plateau of about 300 m diameter on the top, which shows bumpy surface where there are waves, steps and craters of several meters in diameter. The craters imply active or dead cold seeps and are occasionally accompanied by Calyptogena colonies. The plateau is mostly covered with mud. Rock gravels and boulders were observed mainly on outer slope of the knoll. Sidescan sonar and subbottom profiler data by KAIKO system show marked contrasts in sonic reflectivity and penetration between the Kumano Knoll No.4 and the Kumano Basin floor. The high sonic reflectivity and the low penetration on the knoll indicate that main body of the knoll is composed of clastic ejecta as a mud volcano. On the Kumano Knoll No.4, the dives obtained semi-consolidated mudstone, mud breccia, and biotite arkose sandstone. Chronological analysis on nannofossil indicates the sedimentary rocks are in the late Early Miocene through the Middle Miocene. According to this age and geological information on land, it is likely that the sedimentary rocks on the knoll were originally deposited at the beginning of formation of the Kumano Basin. Porosity of these sedimentary rocks is very low (< 18 %). Some mud breccias contain calcite veins that cut the angular mud gravels. These features lead to finding processes until when the sedimentary rocks reached to the seafloor

  11. Institute for Rock Magnetism established

    NASA Astrophysics Data System (ADS)

    Banerjee, Subir K.

    There is a new focal point for cooperative research in advanced rock magnetism. The University of Minnesota in Minneapolis has established an Institute for Rock Magnetism (IRM) that will provide free access to modern equipment and encourage visiting fellows to focus on important topics in rock magnetism and related interdisciplinary research. Funding for the first three years has been secured from the National Science Foundation, the W.M. Keck Foundation, and the University of Minnesota.In the fall of 1986, the Geomagnetism and Paleomagnetism (GP) section of the AGU held a workshop at Asilomar, Calif., to pinpoint important and emerging research areas in paleomagnetism and rock magnetism, and the means by which to achieve them. In a report of this workshop published by the AGU in September 1987, two urgent needs were set forth. The first was for interdisciplinary research involving rock magnetism, and mineralogy, petrology, sedimentology, and the like. The second need was to ease the access of rock magnetists and paleomagnetists around the country to the latest equipment in modern magnetics technology, such as magneto-optics or electronoptics. Three years after the publication of the report, we announced the opening of these facilities at the GP section of the AGU Fall 1990 Meeting. A classified advertisement inviting applications for visiting fellowships was published in the January 22, 1991, issue of Eos.

  12. Definitive Mineralogical Analysis of Martian Rocks and Soil Using the CheMin XRD/XRF Instrument and the USDC Sampler

    NASA Technical Reports Server (NTRS)

    Blake, D. F.; Sarrazin, P.; Chipera, S. J.; Bish, D. L.; Vaniman, D. T.; Bar-Cohen, Y.; Sherrit, S.; Collins, S.; Boyer, B.; Bryson, C.

    2003-01-01

    The search for evidence of extant or extinct life on Mars will initially be a search for evidence of present or past conditions supportive of life (e.g., evidence of water), not for life itself. Definitive evidence of past or present water activity lies in the discovery of: * Hydrated minerals: The "rock type" hosting the hydrated minerals could be igneous, metamorphic, or sedimentary, with only a minor hydrated mineral phase. Therefore, the identification of minor phases is important. * Clastic sediments: Clastic sediments are commonly identified by the fact that they contain minerals of disparate origin that could only have come together as a mechanical mixture. Therefore, the identification of all minerals present in a mixture to ascertain mineralogical source regions is important. * Hydrothermal precipitates and chemical sediments: Some chemical precipitates are uniquely identified only by their structure. For example, Opal A, Opal CT, tridymite, crystobalite, high and low Quartz all have the same composition (SiO2) but different crystal structures indicative of different environments - from hydrothermal hydrothermal formation to low temperature precipitation. Other silica types such as stishovite can provide evidence of shock metamorphism. Therefore, identification of crystal structures and structural polymorphs is important. The elucidation of the nature of the Mars soil will require the identification of mineral components that can unravel its history and the history of the Mars atmosphere.

  13. Quantifying rock mass strength degradation in coastal rock cliffs

    NASA Astrophysics Data System (ADS)

    Brain, Matthew; Lim, Michael; Rosser, Nick; Petley, David; Norman, Emma; Barlow, John

    2010-05-01

    Although rock cliffs are generally perceived to evolve through undercutting and cantilever collapse of material, the recent application of high-resolution three-dimensional monitoring techniques has suggested that the volumetric losses recorded from layers above the intertidal zone produce an equally significant contribution to cliff behaviour. It is therefore important to understand the controls on rockfalls in such layers. Here we investigate the progressive influence of subaerial exposure and weathering on the geotechnical properties of the rocks encountered within the geologically complex coastal cliffs of the northeast coast of England, UK. Through a program of continuous in situ monitoring of local environmental and tidal conditions and laboratory rock strength testing, we aim to better quantify the relationships between environmental processes and the geotechnical response of the cliff materials. We have cut fresh (not previously exposed) samples from the three main rock types (sandstone, mudstone and shale) found within the cliff to uniform size, shape and volume, thus minimizing variability and removing previous surface weathering effects. In order to characterise the intact strength of the rocks, we have undertaken unconfined compressive strength and triaxial strength tests using high pressure (400 kN maximum axial load; 64 MPa maximum cell pressure) triaxial testing apparatus. The results outline the peak strength characteristics of the unweathered materials. We then divided the samples of each lithology into different experimental groups. The first set of samples remained in the laboratory at constant temperature and humidity; this group provides our control. Samples from each of the three rock types were located at heights on the cliff face corresponding with the different lithologies: at the base (mudstone), in the mid cliff (shale) and at the top of the cliff (sandstone). This subjected them to the same conditions experienced by the in situ cliff

  14. Seismic response of rock joints and jointed rock mass

    SciTech Connect

    Ghosh, A.; Hsiung, S.M.; Chowdhury, A.H.

    1996-06-01

    Long-term stability of emplacement drifts and potential near-field fluid flow resulting from coupled effects are among the concerns for safe disposal of high-level nuclear waste (HLW). A number of factors can induce drift instability or change the near-field flow patterns. Repetitive seismic loads from earthquakes and thermal loads generated by the decay of emplaced waste are two significant factors. One of two key technical uncertainties (KTU) that can potentially pose a high risk of noncompliance with the performance objectives of 10 CFR Part 60 is the prediction of thermal-mechanical (including repetitive seismic load) effects on stability of emplacement drifts and the engineered barrier system. The second KTU of concern is the prediction of thermal-mechanical-hydrological (including repetitive seismic load) effects on the host rock surrounding the engineered barrier system. The Rock Mechanics research project being conducted at the Center for Nuclear Waste Regulatory Analyses (CNWRA) is intended to address certain specific technical issues associated with these two KTUs. This research project has two major components: (i) seismic response of rock joints and a jointed rock mass and (ii) coupled thermal-mechanical-hydrological (TMH) response of a jointed rock mass surrounding the engineered barrier system (EBS). This final report summarizes the research activities concerned with the repetitive seismic load aspect of both these KTUs.

  15. 30 CFR 57.3461 - Rock bursts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Rock bursts. 57.3461 Section 57.3461 Mineral...-Underground Only § 57.3461 Rock bursts. (a) Operators of mines which have experienced a rock burst shall— (1) Within twenty four hours report to the nearest MSHA office each rock burst which: (i) Causes persons...

  16. 30 CFR 75.402 - Rock dusting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Rock dusting. 75.402 Section 75.402 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting § 75.402 Rock dusting. All... content to propagate an explosion, shall be rock dusted to within 40 feet of all working faces,...

  17. 30 CFR 75.402 - Rock dusting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Rock dusting. 75.402 Section 75.402 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting § 75.402 Rock dusting. All... content to propagate an explosion, shall be rock dusted to within 40 feet of all working faces,...

  18. 30 CFR 57.3461 - Rock bursts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Rock bursts. 57.3461 Section 57.3461 Mineral...-Underground Only § 57.3461 Rock bursts. (a) Operators of mines which have experienced a rock burst shall— (1) Within twenty four hours report to the nearest MSHA office each rock burst which: (i) Causes persons...

  19. 30 CFR 75.402 - Rock dusting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Rock dusting. 75.402 Section 75.402 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting § 75.402 Rock dusting. All... content to propagate an explosion, shall be rock dusted to within 40 feet of all working faces,...

  20. 30 CFR 75.402 - Rock dusting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Rock dusting. 75.402 Section 75.402 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting § 75.402 Rock dusting. All... content to propagate an explosion, shall be rock dusted to within 40 feet of all working faces,...

  1. 30 CFR 57.3461 - Rock bursts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Rock bursts. 57.3461 Section 57.3461 Mineral...-Underground Only § 57.3461 Rock bursts. (a) Operators of mines which have experienced a rock burst shall— (1) Within twenty four hours report to the nearest MSHA office each rock burst which: (i) Causes persons...

  2. 30 CFR 75.402 - Rock dusting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Rock dusting. 75.402 Section 75.402 Mineral... SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting § 75.402 Rock dusting. All... content to propagate an explosion, shall be rock dusted to within 40 feet of all working faces,...

  3. 30 CFR 57.3461 - Rock bursts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Rock bursts. 57.3461 Section 57.3461 Mineral...-Underground Only § 57.3461 Rock bursts. (a) Operators of mines which have experienced a rock burst shall— (1) Within twenty four hours report to the nearest MSHA office each rock burst which: (i) Causes persons...

  4. 30 CFR 57.3461 - Rock bursts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Rock bursts. 57.3461 Section 57.3461 Mineral...-Underground Only § 57.3461 Rock bursts. (a) Operators of mines which have experienced a rock burst shall— (1) Within twenty four hours report to the nearest MSHA office each rock burst which: (i) Causes persons...

  5. 30 CFR 57.3203 - Rock fixtures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Support-Surface and Underground § 57.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall... grouting material shall not be used. (f) When rock bolts tensioned by torquing are used as a means...

  6. 30 CFR 56.3203 - Rock fixtures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) When rock bolts tensioned by torquing are used as a means of ground support, (1) Selected tension level... § 56.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall— (1) Obtain a...

  7. 30 CFR 56.3203 - Rock fixtures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) When rock bolts tensioned by torquing are used as a means of ground support, (1) Selected tension level... § 56.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall— (1) Obtain a...

  8. 30 CFR 57.3203 - Rock fixtures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Support-Surface and Underground § 57.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall... grouting material shall not be used. (f) When rock bolts tensioned by torquing are used as a means...

  9. 30 CFR 56.3203 - Rock fixtures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) When rock bolts tensioned by torquing are used as a means of ground support, (1) Selected tension level... § 56.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall— (1) Obtain a...

  10. 30 CFR 57.3203 - Rock fixtures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Support-Surface and Underground § 57.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall... grouting material shall not be used. (f) When rock bolts tensioned by torquing are used as a means...

  11. 30 CFR 56.3203 - Rock fixtures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) When rock bolts tensioned by torquing are used as a means of ground support, (1) Selected tension level... § 56.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall— (1) Obtain a...

  12. 30 CFR 57.3203 - Rock fixtures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Support-Surface and Underground § 57.3203 Rock fixtures. (a) For rock bolts and accessories addressed in ASTM F432-95, “Standard Specification for Roof and Rock Bolts and Accessories,” the mine operator shall... grouting material shall not be used. (f) When rock bolts tensioned by torquing are used as a means...

  13. Trace elements in corundum, chrysoberyl, and zircon: Application to mineral exploration and provenance study of the western Mamfe gem clastic deposits (SW Cameroon, Central Africa)

    NASA Astrophysics Data System (ADS)

    Kanouo, Nguo Sylvestre; Ekomane, Emile; Yongue, Rose Fouateu; Njonfang, Emmanuel; Zaw, Khin; Changqian, Ma; Ghogomu, Tanwi Richard; Lentz, David R.; Venkatesh, Akella Satya

    2016-01-01

    Trace element abundances in three indicator minerals (corundum, chrysoberyl, and zircon grains) from the western Mamfe gem placers, as determined by LA-ICP-MS analytical techniques, are shown to be sensitive to their crystallization conditions and source rock types. Corundum is dominantly composed of Al (standardized at 529,300 ppm), Fe (2496-12,899 ppm), and Ti (46-7070 ppm). Among element ratios, Fe/Mg (73-1107), Fe/Ti (0.5-245.0), Ti/Mg (1-175), and Ga/Mg (4-90) are generally higher whereas, Cr/Ga (<0.072) is low. The Fe (≤12,899), Ga (≤398), Mg (2-62), Cr (1.1-33.0), and V (3.0-93.0) contents (in ppm) mostly typify corundum grains formed in magmatic rocks, although some are metamorphic affiliated. A very higher Ti and significantly low Ga, Ta and Nb contents in some blue grains, suggest interesting concentrations of those high-tech metals in their source rocks. Chrysoberyl is dominantly composed of Al (standardized at 425,000 ppm) and Be (62701-64371 ppm). Iron (7605-9225 ppm), Sn (502-3394 ppm), and Ti (33-2251 ppm) contents are high, whereas Ga (333-608 ppm), Ta (<456.0 ppm), and Nb (<3.0 ppm) are significantly low. The high (Be and Sn) and significantly low Ga-Rb abundances, and Ta > Nb in the western Mamfe chrysoberyls show that they were crystallized in granitic pegmatites, with some of those source rocks being enriched in Ta and Sn. Zirconium oxide (ZrO2: standardized at 66.1 wt.%)) is the only major oxide in analysed coarse-grained zircons. Within the minor elementary suites: Hf (4576-12,565 ppm) and Y (48-2805 ppm) contents are significantly high. The trace element suites include: Th (7-1565 ppm), U (13-687 ppm), and ∑REE (50-2161 ppm), whose values are significantly low. The (Yb/Sm)N, Ce/Ce*, and Eu/Eu* anomalies range from 1.0 to 227.0, 0 to 308, and 0.08 to 1.7 respectively. They are Hf-Y-HREE enriched and depleted zircons mainly crystallized in magmatic oxidized environments. They were mainly sorted from granitoids, syenites and kimberlites.

  14. Authigenic K-feldspar in salt rock (Haselgebirge Formation, Eastern Alps)

    NASA Astrophysics Data System (ADS)

    Leitner, Christoph

    2015-04-01

    The crystallisation of authigenic quartz under low temperature, saline conditions is well known (Grimm, 1962). Also the growth of low temperature authigenic feldspar in sediments is a long known phenomenon (Kastner & Siever, 1979; Sandler et al., 2004). In this study we intend to show that halite (NaCl) is a major catalyser for authigenic mineral growth. During late Permian (c. 255-250 Ma), when the later Eastern Alps were located around north of the equator, the evaporites of the Haselgebirge Formation were deposited (Piller et al., 2004). The Haselgebirge Fm. consists in salt mines of a two-component tectonite of c. 50 % halite and 50 % sedimentary clastic and other evaporite rocks (Spötl 1998). Most of the clastic rocks are mud- to siltstones ("mudrock"). During this study, we investigated rare sandstones embedded in salt rock form four Alpine salt mines. Around 40 polished thin sections were prepared by dry grinding for thin section analysis and scanning electron microscopy. The sandstones consist mainly of quartz, K-feldspar, rock fragments, micas, accessory minerals and halite in the pore space. They are fine grained and well sorted. Mudrock clasts in sandstone were observed locally, and also coal was observed repeatedly. Asymmetric ripples were found only in the dimension of millimeters to centimeters. Euhedral halite crystals in pores indicate an early presence of halite. During early diagenesis, authigenic minerals crystallized in the following chronological order. (1) Where carbonate (mainly magnesite) occurred, it first filled the pore space. Plant remains were impregnated with carbonate. (2) Halite precipitated between the detritic sandstone grains. Carbonate grains can be completely embedded in halite. (3) K-feldspar and quartz grains usually expose a detritic core and a later grown euhedral inclusion free rim. Euhedral rims of K-feldspar often also enclose a halite core. K-feldspar replaced the pre-existing halite along former grain boundaries of

  15. Fold-Related Fractures and Postfolding Fracturing, Rock Mass Condition Analyses and Geological Modelling in Turtle Mountain (Alberta Canada).

    NASA Astrophysics Data System (ADS)

    Humair, Florian; Epard, Jean-Luc; Jaboyedoff, Michel; Pedrazzini, Andrea; Froese, Corey

    2010-05-01

    Turtle Mountain is located in the Foothills in southwest Alberta and is formed by highly fractured Paleozoic carbonates rocks and Mesozoic clastic rocks. This area is mainly affected by two major geological structures that are the Turtle Mountain anticline and the Turtle Mountain thrust. This site has become famous after a 30 M m3 rock avalanche of massive limestone and dolostone affecting the eastern mountainside of Turtle Mountain on April 1903. This resulted in more than 70 casualties and buried part of the Frank village. A detailed analysis of predisposing factors leading to failure has been performed using a structural and rock mass condition field analysis (geological and geotechnical mapping, rock mass classification, Schmidt hammer). In addition remote sensing analyses have been provided (High Resolution Digital Elevation Model, Coltop 3D software). The local variations of discontinuity sets and rock mass conditions has been estimated in order to separate the study zone into homogenous structural domains and to correlate them with unstable areas (volumes and failure mechanisms). The aim of this study is to build a theoretical model that shows the relationship between the anticline geometry and the fracturating density. It should be able to determine the origin and the chronology of the discontinuity sets in relation to the tectonic phases (mainly the folding one). A 3D geological model based on several geological profiles performed perpendicular to the Turtle Mountain anticline is necessary to make a detailed analysis. The preliminary results indicate the role of discontinuity sets in the failure mechanisms of the mountain. Moreover if some sets only appear in one limb of the anticline, some others are present in both limbs indicating their posteriority compared with the first ones. Furthermore, a relation between the distance to the fold axis and the quality of the rock mass (Geological Strength Index) has been statistically pointed out, illustrating the

  16. Geology and porphyry copper-type alteration-mineralization of igneous rocks at the Christmas Mine, Gila County, Arizona

    USGS Publications Warehouse

    Koski, Randolph A.

    1979-01-01

    The Christmas copper deposit, located in southern Gila County, Arizona, is part of the major porphyry copper province of southwestern North America. Although Christmas is known for skarn deposits in Paleozoic carbonate rocks, ore-grade porphyry-type copper mineralization also occurs in a composite granodioritic intrusive complex and adjacent mafic volcanic country rocks. This study considers the nature, distribution, and genesis of alteration-mineralization in the igneous rock environment at Christmas. At the southeast end of the Dripping Spring Mountains, the Pennsylvanian Naco Limestone is unconformably overlain by the Cretaceous Williamson Canyon Volcanics, a westward-thinning sequence of basaltic volcanic breccia and lava flows, and subordinate clastic sedimentary rocks. Paleozoic and Mesozoic strata are intruded by Laramide-age dikes, sills, and small stocks of hornblende andesite porphyry and hornblende rhyodacite porphyry, and the mineralized Christmas intrusive complex. Rocks of the elongate Christmas stock, intruded along an east-northeast-trending fracture zone, are grouped into early, veined quartz diorite (Dark Phase), biotite granodiorite porphyry (Light Phase), and granodiorite; and late, unveined dacite porphyry and granodiorite porphyry. Biotite rhyodacite porphyry dikes extending east and west from the vicinity of the stock are probably coeval with biotite granodiorite porphyry. Accumulated normal displacement of approximately 1 km along the northwest-trending Christmas-Joker fault system has juxtaposed contrasting levels (lower, intrusive-carbonate rock environment and upper, intrusive-volcanic rock environment) within the porphyry copper system. K-Ar age determinations and whole-rock chemical analyses of the major intrusive rock types indicate that Laramide calc-alkaline magmatism and ore deposition at Christmas evolved over an extended period from within the Late Cretaceous (~75-80 m.y. ago) to early Paleocene (~63-61 m.y. ago). The sequence of

  17. 2012 Problem 10: Rocking Bottle

    NASA Astrophysics Data System (ADS)

    Li, Yaohua; Gao, Wenli; Wang, Sihui; Zhou, Huijun

    2015-10-01

    In this paper, the motion of a bottle partly filled with water is investigated. Two stages of motion showing different kinetic properties, named as "moving stage" and "rocking stage", can be clearly identified in the experiment. In the moving stage, the bottle moves forward with a short period vibration, while in the rocking stage, the bottle oscillates with a significantly longer period around a certain spot. Theoretical and numerical methods are employed to explain these phenomena. By simplifying the system into a rigid body model, it is found that in the moving stage, classical mechanical method gives results that fit our experiment well. And the rocking stage is thought to be the result of the asymmetric torque generated by the gravity of a liquid layer adhered to the inside wall of the bottle.

  18. SHINING ROCK WILDERNESS, NORTH CAROLINA.

    USGS Publications Warehouse

    Lesure, Frank G.; Dunn, Maynard L.

    1984-01-01

    The Shining Rock Wilderness, in the Blue Ridge Mountains of Haywood County, North Carolina, is underlain by complexly folded mica gneiss and schist of Precambrian age. A mineral-resource survey determined that two commodities, quartz as a source of silica (SiO//2) and gneiss and schist suitable for common building stone and crushed rock, are present in large quantities. Demonstrated resources of silica occur at Shining Rock Mountain and small amounts of sheet muscovite (mica) and scrap mica are present at about 10 localities. Until deep drilling is done to test the results of the seismic studies, no estimate of the potential for gas can be made, but the presence of gas cannot be totally discounted.

  19. Polygon/Cracked Sedimentary Rock

    NASA Technical Reports Server (NTRS)

    2004-01-01

    4 December 2004 Exposures of sedimentary rock are quite common on the surface of Mars. Less common, but found in many craters in the regions north and northwest of the giant basin, Hellas, are sedimentary rocks with distinct polygonal cracks in them. This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an example from the floor of an unnamed crater near 21.0oS, 311.9oW. Such cracks might have formed by desiccation as an ancient lake dried up, or they might be related to ground ice freeze/thaw cycles or some other stresses placed on the original sediment or the rock after it became lithified. The 300 meter scale bar is about 328 yards long. The scene is illuminated by sunlight from the upper left.

  20. Sojourner near the Rock Garden

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image of the Sojourner rover was taken near the end of daytime operations on Sol 42. The rover is between the rocks 'Wedge' (left) and 'Flute Top' (right). Other rocks visible include 'Flat Top' (behind Flute Top) and those in the Rock Garden, at the top of the frame. The cylindrical object extending from the back end of Sojourner is the Alpha Proton X-Ray Spectrometer.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  1. Lowstand versus highstand eustatic models for peat preservation: The coal-bearing rocks of the Breathitt Group, Eastern Kentucky

    SciTech Connect

    Chesnut, D.R. Jr.; Greb, S.F. . Kentucky Geological Survey)

    1992-01-01

    Stratigraphic and chronologic studies suggest that the alternation between major coal beds and clastic rocks of the Lower and Middle Pennsylvanian Breathitt Group (Central Appalachian Basin) resulted from glacial eustacy. The typical Coal-Clastic cycle starts at the top of a major coal bed and consists of a coarsening-upward sequence of marine or brackish-water strata which is commonly truncated and overlain by a fining-upward sequence. The fining-upward sequence is overlain by a rooted paleosol which is overlain by a coal bed. In one scenario, the peat is deposited during the stable highstand period. Because of subsidence, the highstand peat deposit is drowned and covered by marine sediments. During the subsequent lowstand the marine strata are eroded to varying degrees and bare channels are developed, causing an erosional unconformity surface on the marine strata. During transgression, the rise in base-level causes sediments to aggrade within the channels, creating fining-upward sequences above the marine strata. Paleosol development and peat deposition begin again at the next highstand. In another scenario peats are deposited in a coastal setting during lowstand. As transgression proceeds from lowstand, channels backfill and all low-lying areas including peat are covered by coarsening-upward sequences. Peats are then deposited on exposed platforms during highstand. During the subsequent drop in sea level, channels are incised and highstand peats and part of the coarsening-upward sediment package is eroded. The second scenario implies a preservation bias to cyclothems caused by eustatic rates being greater than subsidence rates. Peats are probably deposited during both lowstand and highstand, but lowstand peats are more likely to be preserved.

  2. Sedimentary Rocks in Ladon Vallis

    NASA Technical Reports Server (NTRS)

    2004-01-01

    25 January 2004 This is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) picture of an outcrop of light-toned, layered, sedimentary rock exposed by erosion in Ladon Vallis. These rocks preserve clues to the martian past. However, like books in a library, one needs to go there and check them out if one wishes to read what the layers have to say. This November 2003 picture is located near 21.1oS, 29.8oW, and covers an area 3km (1.9 mi.) wide. Sunlight illuminates the scene from the left.

  3. Sedimentary Rocks of Aram Chaos

    NASA Technical Reports Server (NTRS)

    2004-01-01

    4 February 2004 Aram Chaos is a large meteor impact crater that was nearly filled with sediment. Over time, this sediment was hardened to form sedimentary rock. Today, much of the eastern half of the crater has exposures of light-toned sedimentary rock, such as the outcrops shown in this Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image. The picture is located near 2.0oN, 20.3oW, and covers an area 3 km (1.9 mi) wide. Sunlight illuminates the scene from the left.

  4. Rock 14068 - An unusual lunar breccia.

    NASA Technical Reports Server (NTRS)

    Helz, R. T.

    1972-01-01

    Rock 14068 is a walnut-sized clast of dark breccia from station C1 near Cone Crater. The rock's dominant component is an olivine-rich groundmass. Petrographic and chemical studies were made of polished sections of the rock. The origin of the material is discussed. It is thought possible that the melt was produced by remelting a preexisting lunar rock of the same composition. Another possibility considered is that the rock composition constitutes a mixture of several rock types of partly meteoritic origin.

  5. Coal-rock interface detector

    NASA Technical Reports Server (NTRS)

    Rose, S. D.; Crouch, C. E.; Jones, E. W. (Inventor)

    1979-01-01

    A coal-rock interface detector is presented which employs a radioactive source and radiation sensor. The source and sensor are separately and independently suspended and positioned against a mine surface of hydraulic pistons, which are biased from an air cushioned source of pressurized hydraulic fluid.

  6. Ionium dating of igneous rocks.

    PubMed

    Kigoshi, K

    1967-05-19

    Local fractionation of uranium and thorium, between minerals within a sample of igneous rock at the time of crystallization, makes it possible to date its solidification by use of ionium and uranium. Results on samples of granite, pumice, and lava suggest that this method of dating is reliable.

  7. Plant Communities of Rough Rock.

    ERIC Educational Resources Information Center

    Jacobs, Linda

    A unit of study on plants grown in the Navajo community of Rough Rock, Arizona, is presented in sketches providing the common Navajo name for the plant, a literal English translation, the English name of the plant, and the Latin name. A brief description of each plant includes where the plant grows, how the Navajos use the plant, and the color and…

  8. Microwave dielectric spectrum of rocks

    NASA Technical Reports Server (NTRS)

    Ulaby, F. T.; Bengal, T.; East, J.; Dobson, M. C.; Garvin, J.; Evans, D.

    1988-01-01

    A combination of several measurement techniques was used to investigate the dielectric properties of 80 rock samples in the microwave region. The real part of the dielectric constant, epsilon', was measured in 0.1 GHz steps from 0.5 to 18 GHz, and the imaginary part, epsilon'', was measured at five frequencies extending between 1.6 and 16 GHz. In addition to the dielectric measurements, the bulk density was measured for all the samples and the bulk chemical composition was determined for 56 of the samples. The study shows that epsilon' is frequency-dependent over the 0.5 to 18 GHz range for all rock samples, and that the bulk density rho accounts for about 50 percent of the observed variance of epsilon'. For individual rock types (by genesis), about 90 percent of the observed variance may be explained by the combination of density and the fractional contents of SiO2, Fe2O3, MgO, and TiO2. For the loss factor epsilon'', it was not possible to establish statistically significant relationships between it and the measured properties of the rock samples (density and chemical composition).

  9. Constitutive Equation for Anisotropic Rock

    NASA Astrophysics Data System (ADS)

    Cazacu, O.

    2006-12-01

    In many rocks, due to the existence of well-defined fabric elements such as bedding, layering, foliation or lamination planes, or due to the existence of linear structures, anisotropy can be important. The symmetries most frequently encountered are: transverse isotropy and orthotropy. By adopting both theoretical and experimental approaches, many authors have investigated the effect of the presence within the rock of pronounced anisotropic feature on the mechanical behavior in the elastic regime and on strength properties. Fewer attempts however have been made to capture the anisotropy of rocks in the plastic range. In this paper an elastic/viscoplastic non-associated constitutive equation for an initially transversely isotropic material is presented. The model captures the observed dependency of the elastic moduli on the stress state. The limit of the elastic domain is given by an yield function whose expression is a priori unknown and is determined from data. The basic assumption adopted is that the type of anisotropy of the rock does not change during the deformation process. The anisotropy is thus described by a fourth order tensor invariant with respect to any transformation belonging to the symmetry group of the material. This tensor is assumed to be constant: it does not depend on time nor on deformation; A is involved in the expression of the flow rule, of the yield function, and of the failure criterion in the form of a transformed stress tensor. The components of the anisotropic tensor A are determined from the compressive strengths in conjunction with an anisotropic short- term failure The irreversibility is supposed to be due to transient creep, the irreversible stress work per unit volume being considered as hardening parameter. The adequacy of the model is demonstrated by applying it to a stratified sedimentary rock, Tournemire shale.

  10. Preliminary Study on Rock Avalanche in Taiwan

    NASA Astrophysics Data System (ADS)

    Shen, Y.; Wen, Y.; Hsieh, M.

    2012-12-01

    Rock avalanche is a kind of rapid (average >100 km/h) granule flow caused by crushing and pulverization of rock materials during catastrophic rock slide. Literature researches show that rock avalanches typically occur on steep, high-relief slopes underlain by hard rocks, and have volumes >10,000,000 m3. Rock avalanches also are characterized by long runout distances, which are 5 to 10 times the total fall heights. Some cases can run up the opposing valley wall. Rock avalanches generally occurred in active mountains (e.g., New Zealand) and were triggered by earthquakes or rainfall (snowmelt), but with exceptions. There were few rock avalanches in historical time in Taiwan. This could reflect: (1) intrinsic instability of hillslopes due to weak rock, frequent earthquakes/heavy rains, which resulted in landslides of high frequency/low magnitude; (2) limited runout space along deeply incised river-valley systems, which increased the likelihood of rock-slope failures to transform to debris flows. However, there are ancient rock-avalanche records, found at Shou-shan coast (SW Taiwan) and Shin-she, Chang-pin, Tu-lan along Hua-tung coast (E Taiwan), which is likely to have undergone coseismic uplift. These places, with steep slopes, underlain by hard rock, and free for materials to run, are most prone to rock avalanches in the future.

  11. Rock strength under confined shock conditions

    SciTech Connect

    Scholz, C.H.

    1982-10-01

    This report addresses the laboratory measurements of the static strength of rock needed to simulate the response of rock to an underground explosion. The approach is to identify the variables that affect the strength of rock and to discuss each effect in terms of the underlying processes that cause it. Most of the report is the result of a literature review, although some new analyses and concepts are presented. Attention is directed at three basic rock types: low porosity brittle rock such as granodiorite, high porosity brittle rock such as volcanic tuff, and a rock that may be ductile under the relevant conditions, salt. These three rock types are sufficiently different that somewhat different constitutive laws may have to be used to model their behavior.

  12. Exercise Desert Rock Letter Orders. Army, Camp Desert Rock, Nevada.

    DTIC Science & Technology

    1957-08-01

    WILF.iED J MSGT A19032i3 HJ;,ŕWAY, ELLafGzJN 8FC Xf,37791267 INOZ W, P. 1. PVT2 US52401808 KELLEY, JESSIE J SFC R1� EVaS, LOUIS PFC .,53073109...Ord Co (HAM) Camo Desert Rock, Nevada You will preeeed to Reynolds Funeral Vome, Sigourney, Iowa 0/a 24 AU ist 1957 for apprx fourteen (14) days to

  13. Rock sampling. [apparatus for controlling particle size

    NASA Technical Reports Server (NTRS)

    Blum, P. (Inventor)

    1971-01-01

    An apparatus for sampling rock and other brittle materials and for controlling resultant particle sizes is described. The device includes grinding means for cutting grooves in the rock surface and to provide a grouping of thin, shallow, parallel ridges and cutter means to reduce these ridges to a powder specimen. Collection means is provided for the powder. The invention relates to rock grinding and particularly to the sampling of rock specimens with good size control.

  14. Planetary rock corer and drill concepts

    NASA Technical Reports Server (NTRS)

    Imus, R. E.

    1972-01-01

    Several planetary rock corers and drill design concepts have been developed for obtaining subsurface rock samples in future planetary explorations. Tools are designed for unmanned space vehicles. Two devices are rotary impact multiple chisel trepan rock corer and hole drilling tool.

  15. Rock Music's Place in the Library.

    ERIC Educational Resources Information Center

    Politis, John

    1983-01-01

    Discussion of the importance of rock music as an expression of aural culture includes its history, rock music today, and the development of a rock music collection in the library (placement of collection and books which aid in developing a collection of permanent value). Three references are included. (EJS)

  16. Fungal leaching of titanium from rock.

    NASA Technical Reports Server (NTRS)

    Silverman, M. P.; Munoz, E. F.

    1971-01-01

    Penicillium simplicissimum is found to solubilize up to 80% of the titanium in granitic rocks but less than 2% of the titanium in basaltic rocks. These findings were made in investigating the interactions of microorganisms with rocks and minerals of the biosphere in studies aimed at developing experiments for the detection of extraterrestrial life.

  17. Brittleness Effect on Rock Fatigue Damage Evolution

    NASA Astrophysics Data System (ADS)

    Nejati, Hamid Reza; Ghazvinian, Abdolhadi

    2014-09-01

    The damage evolution mechanism of rocks is one of the most important aspects in studying of rock fatigue behavior. Fatigue damage evolution of three rock types (onyx marble, sandstone and soft limestone) with different brittleness were considered in the present study. Intensive experimental tests were conducted on the chosen rock samples and acoustic emission (AE) sensors were used in some of them to monitor the fracturing process. Experimental tests indicated that brittleness strongly influences damage evolution of rocks in the course of static and dynamic loading. AE monitoring revealed that micro-crack density induced by the applied loads during different stages of the failure processes increases as rock brittleness increases. Also, results of fatigue tests on the three rock types indicated that the rock with the most induced micro-cracks during loading cycles has the least fatigue life. Furthermore, the condition of failure surfaces of the studied rocks samples, subjected to dynamic and static loading, were evaluated and it was concluded that the roughness of failure surfaces is influenced by loading types and rock brittleness. Dynamic failure surfaces were rougher than static ones and low brittle rock demonstrate a smoother failure surface compared to high brittle rock.

  18. Mechanism of Rock Burst Occurrence in Specially Thick Coal Seam with Rock Parting

    NASA Astrophysics Data System (ADS)

    Wang, Jian-chao; Jiang, Fu-xing; Meng, Xiang-jun; Wang, Xu-you; Zhu, Si-tao; Feng, Yu

    2016-05-01

    Specially thick coal seam with complex construction, such as rock parting and alternative soft and hard coal, is called specially thick coal seam with rock parting (STCSRP), which easily leads to rock burst during mining. Based on the stress distribution of rock parting zone, this study investigated the mechanism, engineering discriminant conditions, prevention methods, and risk evaluation method of rock burst occurrence in STCSRP through setting up a mechanical model. The main conclusions of this study are as follows. (1) When the mining face moves closer to the rock parting zone, the original non-uniform stress of the rock parting zone and the advancing stress of the mining face are combined to intensify gradually the shearing action of coal near the mining face. When the shearing action reaches a certain degree, rock burst easily occurs near the mining face. (2) Rock burst occurrence in STCSRP is positively associated with mining depth, advancing stress concentration factor of the mining face, thickness of rock parting, bursting liability of coal, thickness ratio of rock parting to coal seam, and difference of elastic modulus between rock parting and coal, whereas negatively associated with shear strength. (3) Technologies of large-diameter drilling, coal seam water injection, and deep hole blasting can reduce advancing stress concentration factor, thickness of rock parting, and difference of elastic modulus between rock parting and coal to lower the risk of rock burst in STCSRP. (4) The research result was applied to evaluate and control the risk of rock burst occurrence in STCSRP.

  19. Cretaceous rocks from southwestern Montana to southwestern Minnesota, northern Rocky Mountains, and Great Plains

    USGS Publications Warehouse

    Dyman, T.S.; Cobban, W.A.; Fox, J.E.; Hammond, R.H.; Nichols, D.J.; Perry, W.J.; Porter, K.W.; Rice, D.D.; Setterholm, D.R.; Shurr, G.W.; Tysdal, R.G.; Haley, J.C.; Campen, E.B.

    1994-01-01

    In Montana, Wyoming, North and South Dakota, and Minnesota, Cretaceous strata are preserved in the asymmetric Western Interior foreland basin. More than 5,200 m (17,000 ft) of Cretaceous strata are present in southwestern Montana, less than 300 m (1,000 ft) in eastern South Dakota. The asymmetry resulted from varying rates of subsidence due to tectonic and sediment loading. The strata consist primarily of sandstone, siltstone, mudstone, and shale. Conglomerate is locally abundant along the western margin, whereas carbonate is present in most areas of the eastern shelf. Sediment was deposited in both marine and nonmarine environments as the shoreline fluctuated during major tectonic and eustatic cycles.A discussion of Cretaceous strata from southwestern to east-central Montana, the Black Hills, eastern South Dakota, and southwestern Minnesota shows regional stratigraphy and facies relations, sequence, boundaries, and biostratigraphic and radiometric correlations. The thick Cretaceous strata in southwestern Montana typify nonmarine facies of the rapidly subsiding westernmost part of the basin. These strata include more than 3,000 m (10,000 ft) of synorogenic conglomerate of the Upper Cretaceous part of the Beaverhead Group. West of the Madison Range, sequence boundaries bracket the Kootenai (Aptian and Albian), the Blackleaf (Albian and Cenomanian), and the Frontier Formations (Cenomanian and Turonian); sequence boundaries are difficult to recognize because the rocks are dominantly non-marine. Cretaceous strata in east-central Montana (about 1,371 m; 4,500 ft thick) lie at the approximate depositional axis of the basin and are mostly marine terrigenous rocks. Chert-pebble zones in these rocks reflect stratigraphic breaks that may correlate with sequence boundaries to the east and west. Cretaceous rocks of the Black Hills region consist of a predominantly marine clastic sequence averaging approximately 1,524 m (5,000 ft) thick. The Cretaceous System in eastern South

  20. Imaging of rock climbing injuries.

    PubMed

    Martinoli, Carlo; Bianchi, Stefano; Cotten, Anne

    2005-12-01

    Competition climbing has grown increasingly in popularity, and many people are being drawn to this sport with a parallel increase in the occurrence of sport-related injuries. One of the most common and unique lesions occurring in the rock climbing population is the closed rupture of the flexor pulley system of the fingers. This lesion is strictly related to some climbing techniques in which the entire body weight is placed on fingerholds, which causes bowstringing of the flexor tendons with subsequent loss of strength across the full range of motion of the finger. This article summarizes the current literature regarding the application of imaging modalities in the diagnosis of rock climbing injuries with a specific focus on ultrasound and magnetic resonance imaging. Biomechanics of the sporting activity and resultant pathophysiologic and clinical considerations concerning flexor pulley system injuries are also discussed.

  1. Feet injuries in rock climbers.

    PubMed

    Schöffl, Volker; Küpper, Thomas

    2013-10-18

    While injuries of the upper extremity are widely discussed in rock climbers, reports about the lower extremity are rare. Nevertheless almost 50 percent of acute injuries involve the leg and feet. Acute injuries are either caused by ground falls or rock hit trauma during a fall. Most frequently strains, contusions and fractures of the calcaneus and talus. More rare injuries, as e.g., osteochondral lesions of the talus demand a highly specialized care and case presentations with combined iliac crest graft and matrix associated autologous chondrocyte transplantation are given in this review. The chronic use of tight climbing shoes leads to overstrain injuries also. As the tight fit of the shoes changes the biomechanics of the foot an increased stress load is applied to the fore-foot. Thus chronic conditions as subungual hematoma, callosity and pain resolve. Also a high incidence of hallux valgus and hallux rigidus is described.

  2. Sojourner Sits Near Rock Garden

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Mars Pathfinder Rover Sojourner is images by the Imager for Mars Pathfinder as it nears the rock 'Wedge.' Part of the Rock Garden is visible in the upper right of the image.

    Pathfinder, a low-cost Discovery mission, is the first of a new fleet of spacecraft that are planned to explore Mars over the next ten years. Mars Global Surveyor, already en route, arrives at Mars on September 11 to begin a two year orbital reconnaissance of the planet's composition, topography, and climate. Additional orbiters and landers will follow every 26 months.

    The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  3. Feet injuries in rock climbers

    PubMed Central

    Schöffl, Volker; Küpper, Thomas

    2013-01-01

    While injuries of the upper extremity are widely discussed in rock climbers, reports about the lower extremity are rare. Nevertheless almost 50 percent of acute injuries involve the leg and feet. Acute injuries are either caused by ground falls or rock hit trauma during a fall. Most frequently strains, contusions and fractures of the calcaneus and talus. More rare injuries, as e.g., osteochondral lesions of the talus demand a highly specialized care and case presentations with combined iliac crest graft and matrix associated autologous chondrocyte transplantation are given in this review. The chronic use of tight climbing shoes leads to overstrain injuries also. As the tight fit of the shoes changes the biomechanics of the foot an increased stress load is applied to the fore-foot. Thus chronic conditions as subungual hematoma, callosity and pain resolve. Also a high incidence of hallux valgus and hallux rigidus is described. PMID:24147257

  4. Sedimentary Rocks of Aram Chaos

    NASA Technical Reports Server (NTRS)

    2004-01-01

    10 May 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows outcroppings of light-toned, layered, sedimentary rock within Aram Chaos, an ancient, partly-filled impact crater located near 3.2oN, 19.9oW. This 1.5 meters (5 feet) per pixel picture is illuminated by sunlight from the left and covers an area about 3 km (1.9 mi) across.

  5. Relative Permeability of Fractured Rock

    SciTech Connect

    Mark D. Habana

    2002-06-30

    Contemporary understanding of multiphase flow through fractures is limited. Different studies using synthetic fractures and various fluids have yielded different relative permeability-saturation relations. This study aimed to extend the understanding of multiphase flow by conducting nitrogen-water relative permeability experiments on a naturally-fractured rock from The Geysers geothermal field. The steady-state approach was used. However, steady state was achieved only at the endpoint saturations. Several difficulties were encountered that are attributed to phase interference and changes in fracture aperture and surface roughness, along with fracture propagation/initiation. Absolute permeabilities were determined using nitrogen and water. The permeability values obtained change with the number of load cycles. Determining the absolute permeability of a core is especially important in a fractured rock. The rock may change as asperities are destroyed and fractures propagate or st rain harden as the net stresses vary. Pressure spikes occurred in water a solute permeability experiments. Conceptual models of an elastic fracture network can explain the pressure spike behavior. At the endpoint saturations the water relative permeabilities obtained are much less than the nitrogen gas relative permeabilities. Saturations were determined by weighing and by resistivity calculations. The resistivity-saturation relationship developed for the core gave saturation values that differ by 5% from the value determined by weighing. Further work is required to complete the relative permeability curve. The steady-state experimental approach encountered difficulties due to phase interference and fracture change. Steady state may not be reached until an impractical length of time. Thus, unsteady-state methods should be pursued. In unsteady-state experiments the challenge will be in quantifying rock fracture change in addition to fluid flow changes.

  6. Isotopic heterogeneity in volcanic rocks

    NASA Astrophysics Data System (ADS)

    Wolff, J. A.; Ramos, F. C.; Tollstrup, D. L.

    2003-04-01

    The growing microsample database on volcanic rocks is showing that isotopic disequilibrium between and among phenocryst phases, their melt inclusions, and groundmass is the rule rather than the exception. This applies even in cases of little or no petrographic evidence for disequilibrium. Erupted magmas must therefore be regarded, to some extent, as mechanical mixtures of isotopically distinct components assembled from different sources. The preservation of isotopic disequilibrium requires that the assembly takes place before diffusion can eradicate evidence of disequilibrium. For a wide range of magmas (mafic, intermediate and felsic, silica under- and oversaturated) from different volcano types (flood basalts, monogenetic cones, stratocones, silicic calderas) this timescale ranges from thousands of years down to one year or less, with no consistent pattern of mixing-to-eruption time vs. volcano or magma type. Among many issues arising from these findings, we note that estimation of magmatic temperatures from application of equilibrium thermodynamics to phenocryst assemblages in volcanic rocks should be approached with extreme caution. The isotope ratio variations observed among the components of a single volcanic rock sample, in most cases, indicate interaction between magma and the local wall-rock. This is consistent with the view that the vast majority of magmas undergo modification during transport through and residence within the crust. Three physical origins of heterogeneity have been proposed: melting of wallrock, magmatic recharge, and mixing of components within a magma chamber initially segregated into melt-rich and crystal-rich portions. Time constraints on preservation of disequilibrium imply either a causal link with eruption, or that these processes occur through the lifetime of a chamber.

  7. Rock strength reductions during incipient weathering

    NASA Astrophysics Data System (ADS)

    Kelly, P. J.; Anderson, S. P.; Blum, A.

    2012-12-01

    Patrick Kelly, Suzanne Anderson, Alex Blum In rock below the surface, temperature swings are damped, water flow is limited, and biota are few. Yet rock weathers, presumably driven by these environmental parameters. We use rock strength as an indicator of rock weathering in Gordon Gulch in the Boulder Creek Critical Zone Observatory, a watershed at 2500 m underlain by Proterozoic gneiss intruded by the Boulder Creek granodiorite. Fresh rock is found at depths of 8-30 m in this area, and the thickness of the weathered rock zone imaged with shallow seismic refraction is greater on N-facing slopes than S-facing slopes (Befus et al., 2011, Vadose Zone J.). We use the Brazilian splitting test to determine tensile strength of cores collected with a portable drilling rig. Spatial variations in rock strength that we measure in the top 2 m of the weathered rock mantle can be connected to two specific environmental variables: slope aspect and the presence of a soil mantle. We find weaker rock on N-facing slopes and under soil. There is no clear correlation between rock strength and the degree of chemical alteration in these minimally weathered rocks. Denudation rates of 20-30 microns/yr imply residence times of 105-106 years within the weathered rock layers of the critical zone. Given these timescales, rock weathering is more likely to have occurred under glacial climate conditions, when periglacial processes prevailed in this non-glaciated watershed. Incipient weathering of rock appears to be controlled by water and frost cracking in Gordon Gulch. Water is more effectively delivered to the subsurface on N-facing slopes, and is more likely held against rock surfaces under soil than on outcrops. These moisture conditions, and the lower surface temperatures that prevail on N-facing slopes also favor frost cracking as an important weathering process.

  8. Thermal conductivity of carbonate rocks

    USGS Publications Warehouse

    Thomas, J.; Frost, R.R.; Harvey, R.D.

    1973-01-01

    The thermal conductivities of several well-defined carbonate rocks were determined near 40??C. Values range from 1.2 W m-1 C-1 for a highly porous chalk to 5.1 W m-1 C-1 for a dolomite. The thermal conductivity of magnesite (5.0) is at the high end of the range, and that for Iceland Spar Calcite (3.2) is near the middle. The values for limestones decrease linearly with increasing porosity. Dolomites of comparable porosity have greater thermal conductivities than limestones. Water-sorbed samples have expected greater thermal conductivities than air-saturated (dry) samples of the same rock. An anomalously large increase in the thermal conductivity of a water-sorbed clayey dolomite over that of the same sample when dry is attributed to the clay fraction, which swells during water inhibition, causing more solid-to-solid contacts within the dolomite framework. Measurements were made with a Colora Thermoconductometer. Chemical and mineralogical analyses were made and tabulated. Porosity of the rocks was determined by mercury porosimetry and also from density measurements. The Iceland Spar Calcite and magnesite were included for reference. ?? 1973.

  9. The Call of the Dark Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This approximate true-color rendering from NASA's Mars Exploration Rover Spirit shows a set of darker rocks dubbed 'Toltecs' lying southeast of the rover's current position. These rocks are believed to be basaltic, or volcanic, in composition, because their spectral properties match those of other basaltic rocks studied in Gusev Crater. Scientists hope to use these presumably unaltered rocks as a geologic standard for comparison to altered rocks in the area, such as 'Clovis.' This image was taken with the panoramic camera's 600-, 530-, and 480-nanometer filters on sol 220 (Aug. 15, 2004).

  10. The Call of the Dark Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This false-color image taken by the Mars Exploration Rover Spirit shows a group of darker rocks dubbed 'Toltecs,' lying to the southeast of the rover's current position. The rocks are believed to be basaltic, or volcanic, in composition because their color and spectral properties resemble those of basaltic rocks studied so far at Gusev Crater. Scientists hope to use these presumably unaltered rocks as a geologic standard for comparison to altered rocks in the area, such as 'Clovis.' This image was taken by the 750-, 530- and 430-nanometer filters of rover's panoramic camera on sol 220 (August 15, 2004).

  11. Dispersivity as an oil reservoir rock characteristic

    SciTech Connect

    Menzie, D.E.; Dutta, S.

    1989-12-01

    The main objective of this research project is to establish dispersivity, {alpha}{sub d}, as an oil reservoir rock characteristic and to use this reservoir rock property to enhance crude oil recovery. A second objective is to compare the dispersion coefficient and the dispersivity of various reservoir rocks with other rock characteristics such as: porosity, permeability, capillary pressure, and relative permeability. The dispersivity of a rock was identified by measuring the physical mixing of two miscible fluids, one displacing the other in a porous medium. 119 refs., 27 figs., 12 tabs.

  12. 3. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. SOUTH ELEVATION IN UNALTERED CONDITION. DATED MARCH 19, 1945. - Rock Island Arsenal, Building No. 61, Rodman Avenue & First Street, Rock Island, Rock Island County, IL

  13. 4. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. LOOKING NORTH AFTER ADDITION OF CONICAL ROOF. ORIGINALLY PUBLISHED 1887. - Rock Island Arsenal, Building No. 53, North Avenue North of Midpoint, Rock Island, Rock Island County, IL

  14. 9. Photograph of photograph in possession of Rock Island Arsenal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Photograph of photograph in possession of Rock Island Arsenal Historical Office. WEST AND NORTH ELEVATIONS. ORIGINALLY PUBLISHED 1887. - Rock Island Arsenal, Building No. 90, East Avenue between North Avenue & King Drive, Rock Island, Rock Island County, IL

  15. 7. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. SOUTH AND EAST ELEVATIONS. DATED MARCH 19, 1945. - Rock Island Arsenal, Building No. 62, Rodman Avenue between First & Second Streets, Rock Island, Rock Island County, IL

  16. 3. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. NORTH ELEVATION IN UNALTERED CONDITION. DATED NOVEMBER 21, 1944. - Rock Island Arsenal, Building No. 103, Rodman Avenue & First Street, Rock Island, Rock Island County, IL

  17. 8. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. SOUTH ELEVATON IN UNALTERED CONDITION. ORIGINALLY PUBLISHED 1898. - Rock Island Arsenal, Building No. 68, Rodman Avenue between Fourth Street & East Avenue, Rock Island, Rock Island County, IL

  18. 10. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. INTERIOR, LOOKING WEST. DATED OCTOBER 2, 1945. - Rock Island Arsenal, Building No. 138, Second Avenue between South Avenue & Ramsey Street, Rock Island, Rock Island County, IL

  19. 10. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. SOUTH AND WEST ELEVATIONS IN UNALTERED CONDITION. DATED APRIL 18, 1941. - Rock Island Arsenal, Building No. 56, North Avenue & East Avenue, Rock Island, Rock Island County, IL

  20. 11. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. BASEMENT, SHOWING ORIGINAL OPEN INTERIOR PLAN. DATED APRIL 7, 1942. - Rock Island Arsenal, Building No. 56, North Avenue & East Avenue, Rock Island, Rock Island County, IL

  1. 4. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. NORTH ELEVATION IN UNALTERED CONDITION. DATED NOVEMBER 21, 1944. - Rock Island Arsenal, Building No. 109, Rodman Avenue & Fourth Street, Rock Island, Rock Island County, IL

  2. 4. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. NORTH AND WEST ELEVATIONS. DATED NOVEMBER 21, 1944. - Rock Island Arsenal, Building No. 108, Rodman Avenue between Third & Fourth Streets, Rock Island, Rock Island County, IL

  3. 5. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. INTERIOR AFTER REMODELING INTO OFFICE SPACE. DATED FEBRUARY 13, 1943. - Rock Island Arsenal, Building No. 67, Rodman Avenue & Fourth Street, Rock Island, Rock Island County, IL

  4. 5. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. WEST ELEVATION IN UNALTERED CONDITION. ORIGINALLY PUBLISHED 1898. - Rock Island Arsenal, Building No. 280, Sylvan Drive, Rock Island, Rock Island County, IL

  5. 23. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. VERTICAL WESTINGHOUSE GENERATORS IN 1919 ADDITION. DATED FEBRUARY 19, 1919. - Rock Island Arsenal, Building No. 160, Sylvan Drive, Rock Island, Rock Island County, IL

  6. Petrology of unshocked crystalline rocks and shock effects in lunar rocks and minerals

    USGS Publications Warehouse

    Chao, E.C.T.; James, O.B.; Minkin, J.A.; Boreman, J.A.; Jackson, E.D.; Raleigh, C.B.

    1970-01-01

    On the basis of rock modes, textures, and mineralogy, unshocked crystalline rocks are classified into a dominant ilmenite-rich suite (subdivided into intersertal, ophitic, and hornfels types) and a subordinate feldspar-rich suite (subdivided into poikilitic and granular types). Weakly to moderately shocked rocks show high strain-rate deformation and solid-state transformation of minerals to glasses; intensely shocked rocks are converted to rock glasses. Data on an unknown calcium-bearing iron metasilicate are presented.

  7. Internal structure of fault zones in geothermal reservoirs: Examples from palaeogeothermal fields and potential host rocks

    NASA Astrophysics Data System (ADS)

    Leonie Philipp, Sonja; Reyer, Dorothea; Meier, Silke; Bauer, Johanna F.; Afşar, Filiz

    2014-05-01

    Fault zones commonly have great effects on fluid transport in geothermal reservoirs. During fault slip all the pores and small fractures that meet with the slip plane become interconnected so that the inner part of the fault, the fault core, consisting of breccia or gouge, may suddenly develop a very high permeability. This is evidenced, for example by networks of mineral veins in deeply eroded fault zones in palaeogeothermal fields. Inactive faults, however, may have low permeabilities and even act as flow barriers. In natural and man-made geothermal reservoirs, the orientation of fault zones in relation to the current stress field and their internal structure needs be known as accurately as possible. One reason is that the activity of the fault zone depends on its angle to the principal stress directions. Another reason is that the outer part of a fault zone, the damage zone, comprises numerous fractures of various sizes. Here we present field examples of faults, and associated joints and mineral veins, in palaeogeothermal fields, and potential host rocks for man-made geothermal reservoirs, respectively. We studied several localities of different stratigraphies, lithologies and tectonic settings: (1) 58 fault zones in 22 outcrops from Upper Carboniferous to Upper Cretaceous in the Northwest German Basin (siliciclastic, carbonate and volcanic rocks); (2) 16 fault zones in 9 outcrops in Lower Permian to Middle Triassic (mainly sandstone, limestone and granite) in the Upper Rhine Graben; and (3) 74 fault zones in two coastal sections of Upper Triassic and Lower Jurassic age (mudstones and limestone-marl alternations) in the Bristol Channel Basin, UK. (1) and (2) are outcrop analogues of geothermal reservoir horizons, (3) represent palaeogeothermal fields with mineral veins. The field studies in the Northwest German Basin (1) show pronounced differences between normal-fault zones in carbonate and clastic rocks. In carbonate rocks clear damage zones occur that are

  8. Water in evolved lunar rocks

    NASA Astrophysics Data System (ADS)

    Robinson, Katharine Lynn

    The Moon was thought to be completely anhydrous until indigenous water was found in lunar samples in 2008. This discovery raised two fundamental questions about the Moon: how much water is present in the bulk Moon and is water uniformly distributed in the lunar interior? To address these questions, I studied a suite of lunar samples rich in a chemical component called KREEP (K, Rare Earth Elements, P), all of which are incompatible elements. Water behaves as an incompatible element in magmas, so KREEP-rich lunar samples are potentially water rich. In this dissertation, I present the results of a petrologic study of KREEP-rich lunar rocks, measurements of their water contents and deuterium (D) to hydrogen (H) ratios (D/H), and examined where these rocks fit into our understanding of water in the Moon as a whole. We performed a study of highly evolved, KREEP-rich lunar rocks called felsites and determined that they contain quartz. Using cooling rates derived from quartz-Ti thermometry, we show the felsites originated at a minimum pressure of ˜1 kbar, corresponding to a minimum depth of 20-25 km in the lunar crust. We calculate that at that pressure water would have been soluble in the melt, indicating that degassing of H2O from the felsite parental melts was likely minimal and hydrogen isotopes in intrusive rocks are likely unfractionated. We then measured D/H in apatite in KREEP-rich intrusive rocks to clarify the solar system source of the Moon's water. When viewed in the context of other lunar D/H studies, our results indicate there are at least three distinctive reservoirs in the lunar interior, including an ultra-low D reservoir that could represent a primitive component in the Moon's interior. Furthermore, our measurements of residual glass in a KREEP basalt show that the KREEP basaltic magmas contained 10 times less water than the source of the Apollo 17 pyroclastic glass beads, indicating that, though wetter than previously thought, the concentration of

  9. Rock support system development test plan

    SciTech Connect

    Patricio, J.G. . Rockwell Hanford Operations)

    1984-03-30

    The Test Plan has been prepared to support design activities for the development of a rock support system for a Nuclear Waste Repository in Basalt (NWRB). The rock support system is assumed to consist of a combination of shotcrete and rock bolts. The seven testing activities include mix development and physical testing of shotcrete, durability testing of shotcrete, durability testing of rock bolt grouts, field tests on rock bolts, field testing of shotcrete, and heated room test. The objective of the Test Plan is to develop required data through combined laboratory, field, and office studies for design and design validation of the rock support system. The overall Test Plan is developed to provide a logical progression from laboratory tests performed to characterize fundamental thermomechanical properties of shotcrete and grouts, to field tests on rock bolts and shotcrete, and in situ performance tests. 21 refs., 15 figs., 33 tabs.

  10. Rock Magnetism: Successes and Mysteries

    NASA Astrophysics Data System (ADS)

    Dunlop, D. J.

    2011-12-01

    Louis Néel once proposed making ships "invisible" (i.e., magnetically undetectable) by giving them a permanent or remanent magnetism that would cancel the signal induced by the Earth's magnetic field. Like much of rock magnetism, this borders on the magical. Rocks possess a magnetic memory that verges on the phenomenal. An adequate magnetic lifetime for your credit card is until its expiry date and one must avoid exposure to magnetic fields and heat. But a rock's magnetic memory is forever, and the recipe for that durability includes, for igneous and metamorphic rocks, exposure to ancient fields while hot - near the Curie temperature in fact. The thermal remanent magnetism (TRM) thus produced is largely immune to later field changes at lower temperatures although luckily a fraction - a partial TRM overprint - does record later heating events, e.g., burial during major orogenies. When we lift the veil and look closely, on a microscale or nanoscale, it is perplexing to understand why paleomagnetism works so well when rocks seemingly contain so few of Néel's ideal recorders: single-domain grains with tightly coupled atomic spins. In larger grains with multiple domains, the walls between neighbouring domains move readily, like dislocations in crystals, enlarging some domains at the expense of others. This mutability makes any magnetic memory of multi-domain grains suspect. But around the threshold between single-domain and multi-domain structures - a specific grain size that varies widely from one magnetic mineral to another - there are recent predictions and observations of novel structures, including linked magnetic moments of nearby grains and interfacial moments of exsolved phases, that could go some way towards explaining why single-domain-like behaviour is so widespread. Many magnetic properties show an almost continuous variation with grain size, quite unlike the expected discontinuity at the single-domain threshold. Among these is initial susceptibility which

  11. Siberian Origins of Neoproterozoic to Upper Triassic Rocks of Arctic Alaska

    NASA Astrophysics Data System (ADS)

    Clough, J. G.; Blodgett, R. B.

    2007-12-01

    found in the Canadian Arctic Islands Richly diverse Upper Triassic fauna (halobiid and monotid bivalves, brachiopods) are present in the both the Shublik Formation and Otuk Group. These show closer affinities with NE Siberia rather than to western or northern North America, suggesting close spatial relationships between Siberia and Arctic Alaska at least until Late Triassic time. Sedimentary provenance studies in eastern Brooks Range Precambrian rocks indicate age ranges that are dissimilar to Proterozoic detrital-zircon ages from clastic rocks of the northern Canadian Cordillera and Canadian Arctic Islands where a detrital source within the Grenville orogen is indicated. Paleocurrent directions for the Neoproterozoic Katakturuk Dolomite in the northeast Brooks Range and similar-age units in the adjacent Victoria Island and Amundsen Basin are in approximately 100 degree opposition for a counterclockwise rotational- restored Arctic Alaska. Upper Devonian clastics of northern Alaska are in 180 degree opposition to coeval units in the Canadian Arctic Islands when the Arctic Alaska plate is restored in the rotational model. Therefore, based on paleobiogeography, sediment provenance, stratigraphy and sedimentology, tectonic models for the opening of the Canada Basin must take into account that Triassic and older rocks in Arctic Alaska have Siberian origins or were deposited proximal to Siberia.

  12. Palaeomagnetism and rock magnetism of the Permian redbeds from the Velebit Mt. (Karst Dinarides, Croatia): dating of the early Alpine tectonics in the Western Dinarides by a secondary magnetization

    NASA Astrophysics Data System (ADS)

    Werner, Tomasz; Lewandowski, Marek; Vlahović, Igor; Velić, Ivo; Sidorczuk, Magdalena

    2015-05-01

    The studied area of the Velebit Mt., a part of the Adria microplate, belonged to a NE margin of Gondwana during the Carboniferous and Permian. While the Carboniferous to the Early Permian was characterised by deposition of clastic rocks, younger sedimentation was dominated by a thick sequence of carbonate rocks. The Lower Permian deposits of the core part of the Velebit Mt. at Košna and Crne Grede localities were investigated using palaeomagnetic and rock magnetic measurements. The main remanence carriers were recognized as haematite with an increasing contribution of SP/SD magnetite in younger subsections. The AMS fabric with low anisotropy ratio (1-3%) is strongly oblate at Košna and weakly prolate at Crne Grede, reflecting differences in the contribution of magnetic phases. A significant remagnetization of the Permian rocks, as proved by results of a conglomerate test, probably caused by a combination of elevated temperatures and fluid migration, may be assigned to burial-related processes that affected the rocks before the final uplift of the Dinarides. Characteristic remanent magnetizations recorded in haematite are apparently similar to the Permian direction for Africa (shallow inclination with NNW declination), as expected for Velebit Mt. coordinates. Paradoxically, this orientation is observed in situ within the almost vertically dipping beds. We explain this relationship assuming a syn-folding Cretaceous remagnetization of the rocks at their subhorizontal position (ca. 30°S), in which a mean vector of the secondary remanence overlaps with the Cretaceous direction, expected for Africa at the Velebit Mt. geographical coordinates. Consequently, our results indirectly point to the Cretaceous time of incipient stages of the Dinaric tectonism, and suggest African geotectonic affinity of the Velebit rocks. No important vertical-axis rotation is implied by our results, in contrast to previously published data. The puzzling complete remagnetization carried by

  13. Infiltration flux distributions in unsaturated rock deposits andtheir potential implications for fractured rock formations

    SciTech Connect

    Tokunaga, Tetsu K.; Olson, Keith R.; Wan, Jiamin

    2004-11-01

    Although water infiltration through unconsolidated rocks and fractured rock formations control flow and transport to groundwater, spatial distributions of flow paths are poorly understood. Infiltration experiments conducted on packs of rocks showed that a well-constrained distribution of fluxes develops despite differences in rock type (angular diabase and sandstone, and subangular serpentinite), rock size (30 to 200mm), and packing (up to 42 rock layers). Fluxes stabilize into a geometric (exponential) distribution that keeps about half of the system depleted of flow, retains a small fraction of high flow regions, and has a characteristic scale determined by the rock size. Modification of a statistical mechanical model shows that gravity-directed, random flowpaths evolve to the observed flux distribution, and that it represents the most probable distribution. Key similarities between infiltration in rock deposits and fractured rock formations indicate that the geometric flow distribution may also apply in the latter systems.

  14. Hot Dry Rock; Geothermal Energy

    SciTech Connect

    1990-01-01

    The commercial utilization of geothermal energy forms the basis of the largest renewable energy industry in the world. More than 5000 Mw of electrical power are currently in production from approximately 210 plants and 10 000 Mw thermal are used in direct use processes. The majority of these systems are located in the well defined geothermal generally associated with crustal plate boundaries or hot spots. The essential requirements of high subsurface temperature with huge volumes of exploitable fluids, coupled to environmental and market factors, limit the choice of suitable sites significantly. The Hot Dry Rock (HDR) concept at any depth originally offered a dream of unlimited expansion for the geothermal industry by relaxing the location constraints by drilling deep enough to reach adequate temperatures. Now, after 20 years intensive work by international teams and expenditures of more than $250 million, it is vital to review the position of HDR in relation to the established geothermal industry. The HDR resource is merely a body of rock at elevated temperatures with insufficient fluids in place to enable the heat to be extracted without the need for injection wells. All of the major field experiments in HDR have shown that the natural fracture systems form the heat transfer surfaces and that it is these fractures that must be for geothermal systems producing from naturally fractured formations provide a basis for directing the forthcoming but, equally, they require accepting significant location constraints on HDR for the time being. This paper presents a model HDR system designed for commercial operations in the UK and uses production data from hydrothermal systems in Japan and the USA to demonstrate the reservoir performance requirements for viable operations. It is shown that these characteristics are not likely to be achieved in host rocks without stimulation processes. However, the long term goal of artificial geothermal systems developed by systematic

  15. Mars Rocks Continue to Fascinate

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Proving once again that Mars is a complex and fascinating place, NASA's Opportunity rover has entered new terrain and is providing scientists with more discoveries and puzzles to solve. 'One of the things we've been wondering,' said principal investigator Steve Squyres, 'is whether the rounded concretions we call 'blueberries' are the same everywhere. It turns out they're not. The berries are more numerous here, and some seem to be smaller than any we've ever seen.'

    This microscopic image of a drill hole cut into a martian rock nicknamed 'Ice Cream' by the rover's rock abrasion tool shows cross sections of round concretions 1 to 2 millimeters (0.04 to 0.08 inches) wide. Science team members are debating whether the grayish-looking smudges that are not as round are concretions or some other feature.

    Opportunity is now almost 4 kilometers (2.5 miles) south of 'Endurance Crater,' where the rover spent from May through December of 2004 reading the story of a watery past recorded in the martian rocks. After exiting 'Endurance' on martian day, or sol, 316 (Dec. 13, 2004), Opportunity turned south and continued the trek across land where no human has trod, demonstrating that endurance is more than just a name.

    Opportunity took this mosaic of images with its microscopic imager on sol 546 (Aug. 6, 2005). The area shown is approximately 6 centimeters (2.4 inches) wide. The shaded portions on the left side of each quadrangle in the mosaic are silhouettes of the rover's robotic arm.

  16. Big Bang Day : Physics Rocks

    ScienceCinema

    None

    2016-07-12

    Is particle physics the new rock 'n' roll? The fundamental questions about the nature of the universe that particle physics hopes to answer have attracted the attention of some very high profile and unusual fans. Alan Alda, Ben Miller, Eddie Izzard, Dara O'Briain and John Barrowman all have interests in this branch of physics. Brian Cox - CERN physicist, and former member of 90's band D:Ream, tracks down some very well known celebrity enthusiasts and takes a light-hearted look at why this subject can appeal to all of us.

  17. Sedimentary rocks of early Mars.

    PubMed

    Malin, M C; Edgett, K S

    2000-12-08

    Layered and massive outcrops on Mars, some as thick as 4 kilometers, display the geomorphic attributes and stratigraphic relations of sedimentary rock. Repeated beds in some locations imply a dynamic depositional environment during early martian history. Subaerial (such as eolian, impact, and volcaniclastic) and subaqueous processes may have contributed to the formation of the layers. Affinity for impact craters suggests dominance of lacustrine deposition; alternatively, the materials were deposited in a dry, subaerial setting in which atmospheric density, and variations thereof mimic a subaqueous depositional environment. The source regions and transport paths for the materials are not preserved.

  18. Microscopic tubes in igneous rocks

    NASA Technical Reports Server (NTRS)

    Richter, D.; Simmons, G.

    1977-01-01

    Microscopic tubes have been observed in several igneous rocks and may be quite common. They occur in single crystals and have either elliptical or circular cross-sections 1 to 5 microns in diameter and are ten to hundreds of microns long. Microtubes may be hollow or partially or completely filled with another phase, but are distinct from acicular crystals of accessory minerals such as rutile. Microtubes can form by at least three processes: (1) the partial annealing of microcracks, (2) the natural etching of dislocations, or (3) the primary inclusion of fluid material during crystal growth.

  19. Big Bang Day : Physics Rocks

    SciTech Connect

    2009-10-07

    Is particle physics the new rock 'n' roll? The fundamental questions about the nature of the universe that particle physics hopes to answer have attracted the attention of some very high profile and unusual fans. Alan Alda, Ben Miller, Eddie Izzard, Dara O'Briain and John Barrowman all have interests in this branch of physics. Brian Cox - CERN physicist, and former member of 90's band D:Ream, tracks down some very well known celebrity enthusiasts and takes a light-hearted look at why this subject can appeal to all of us.

  20. Rock Goes to School on Screen: A Model for Teaching Non-"Learned" Musics Derived from the Films "School of Rock" (2003) and "Rock School" (2005)

    ERIC Educational Resources Information Center

    Webb, Michael

    2007-01-01

    What can be learned from two films with "rock" and "school" in their titles, about rock in school and about music and schooling more broadly? "School of Rock" (2003), a "family comedy," and "Rock School" (2005), a documentary, provoke a range of questions, ideological and otherwise, surrounding the inclusion of rock in formal instructional…

  1. Co-seismic thermal dissociation of carbonate fault rocks: Naukluft Thrust, central Namibia

    NASA Astrophysics Data System (ADS)

    Rowe, C. D.; Miller, J. A.; Sylvester, F.; Backeberg, N.; Faber, C.; Mapani, B.

    2009-12-01

    Frictional heating has been shown to dissociate carbonate minerals in fault rocks and rock slides at high velocities, producing in-situ fluid pressure spikes and resulting in very low effective friction. We describe the textural and geochemical effects of repeated events of frictional-thermal dissociation and fluidization along a low-angle continental thrust fault. The Naukluft Thrust in central Namibia is a regional décollement along which the Naukluft Nappe Complex was emplaced over the Nama Basin in the southern foreland of the ~ 550Ma Damara Orogen. Fault rocks in the thrust show a coupled geochemical and structural evolution driven by dolomitization reactions during fault activity and facilitated by fluid flow along the fault surface. The earliest developed fault rocks are calcite-rich calcmylonites which were progressively dolomitized along foliation. Above a critical dolomite/calcite ratio, the rocks show only brittle deformation fabrics dominated by breccias, cataclasites, and locally, a thin (1-3cm) microcrystalline, smooth white ultracataclasite. The fault is characterized by the prevalence of an unusual “gritty dolomite” yellow cataclasite containing very well rounded clasts in massive to flow-banded fine dolomitic matrix. This cataclasite, locally known as the “gritty dolomite”, may reach thicknesses of up to ~ 10m without evidence of internal cross-cutting relations with randomly distributed clasts (an “unsorted” texture). The gritty dolomite also forms clastic injections into the hanging wall of the fault, frequently where the fault surface changes orientation. Color-cathodoluminescence images show that individual carbonate grains within the “gritty dolomite” have multiple layers of thin (~10-100 micron) dolomite coatings and that the grains were smoothed and rounded between each episode of coating precipitation. Coated grains are in contact with one another but grain cores are never seen in contact. CL-bright red dolomite which forms

  2. A Jurassic Shock-Aftershock Earthquake Sequence Recorded by Small Clastic Pipes and Dikes within Dune Cross-Strata, Zion National Park, Utah

    NASA Astrophysics Data System (ADS)

    Loope, D. B.; Zlotnik, V. A.; Kettler, R. M.; Pederson, D. T.

    2012-12-01

    dune lee slope through a pipe, the erupted sand dried and was buried by climbing wind-ripple strata as the large dune continued to advance downwind. The mapped cluster recording eight distinct seismic events lies within thin-laminated sediment that was deposited by wind ripples during 1 m (~ 1 year) of southeastward dune migration. We conclude that the small pipes and dikes of our study sites are products of numerous >MM 5 earthquakes, some of which recurred at intervals of less than 2 months. We interpret one small cluster of pipes and dikes with well-defined upward terminations as a distinct shock-aftershock sequence. Because the largest modern earthquakes can produce surface liquefaction only up to about 175 km from their epicenters, the Jurassic epicenters must have been well within that distance. The tendency of modern plate boundaries to produce high-frequency aftershocks suggests that the epicenter for this Jurassic sequence lay to the southwest, within the plate boundary zone (not within continental rocks to the east). As eolian dunes steadily migrate over interdune surfaces underlain by water-saturated dune cross-strata, the thin, distinct laminae produced by the wind ripples that occupy dune toes can faithfully record high-frequency seismic events.

  3. Multisensor classification of sedimentary rocks

    NASA Technical Reports Server (NTRS)

    Evans, Diane

    1988-01-01

    A comparison is made between linear discriminant analysis and supervised classification results based on signatures from the Landsat TM, the Thermal Infrared Multispectral Scanner (TIMS), and airborne SAR, alone and combined into extended spectral signatures for seven sedimentary rock units exposed on the margin of the Wind River Basin, Wyoming. Results from a linear discriminant analysis showed that training-area classification accuracies based on the multisensor data were improved an average of 15 percent over TM alone, 24 percent over TIMS alone, and 46 percent over SAR alone, with similar improvement resulting when supervised multisensor classification maps were compared to supervised, individual sensor classification maps. When training area signatures were used to map spectrally similar materials in an adjacent area, the average classification accuracy improved 19 percent using the multisensor data over TM alone, 2 percent over TIMS alone, and 11 percent over SAR alone. It is concluded that certain sedimentary lithologies may be accurately mapped using a single sensor, but classification of a variety of rock types can be improved using multisensor data sets that are sensitive to different characteristics such as mineralogy and surface roughness.

  4. Electrical properties of dry rocks

    NASA Technical Reports Server (NTRS)

    Morrison, H.

    1973-01-01

    The mechanism by which atmospheric moisture affects the conductivity and dielectric constant of rock specimens was studied in time and frequency domains. It is suggested that adsorbed water molecules alter the surface conductivity in a manner similar to that observed in semiconductors and insulators. Powdered basalts show a low-frequency dispersion produced by the atmospheric moisture remaining in the pore system of the sample in a high vacuum; this effect is attributed to isolated adsorption centers. Simulated lunar permafrost at 100 K and a vacuum of 10 to the -8th power torr together with data on lunar samples contaminated with atmospheric moisture and the dielectric properties of ice at various temperatures indicate that, if permafrost exists in the moon it should present a relaxation peak at approximately 300 Hz; for temperatures up to 263 K it may go up to 20 KHz. It is concluded that in order to have electrical steady state conditions in rock samples it is necessary to have volume charge accumulations at interfaces within the sample and at the electrode sample interface. A method for measuring heterogeneous dielectrics with non-negligible ohmic and dielectric conductivities is proposed and experimentally verified.

  5. Multiversos: Rock'n'Astronomy

    NASA Astrophysics Data System (ADS)

    Caballero, J. A.; Arias, A.; García, N.

    2011-11-01

    Imagine that you can use your fingers only for typing target coordinates at thetelescope, reduce images and spectra with IRAF, or write papers for Astronomy &Astrophysics, but you would never be able to play an electric guitar.Imagine that you love music, work in front of the computer always withheadphones, and dream of playing with your favourite rock band in a tumultuousconcert.Imagine that you are an astronomer who, after a "cosmic fluke", share stagewith the band which themes you have always hummed since you were a teenager.Imagine that you were born for rock, played a main role in the best Spanishalbum of the 90s (Omega, with Enrique Morente), and your songs arerutinary played by Radio 3, but you would never be able to detect an exoplanetor a galaxy at a high redshift.Imagine that you love Astronomy, try to see the Moon craters and Andromeda withyour small telescope through the light pollution of your city, and explain yourdaughter that Pluto is not a planet any longer. Imagine that you are a musician who, after a "cosmic fluke", give a talk justafter a Nobel laureate that discovered the cosmic microwave backgroundradiation.Such "cosmic flukes" sometimes happen. If you were not at the dinner of the SEA meeting and do not believe us, visithttp://www.myspace.com/antonioariasmultiverso or open the proceedings DVD andlisten "El ordenador simula el nacimiento de las estrella...".

  6. Hand injuries in rock climbers.

    PubMed

    Kubiak, Erik N; Klugman, Jeffrey A; Bosco, Joseph A

    2006-01-01

    Rock climbing, whether practiced in nature on cliffs and boulders or indoors on walls made of resin and wood, has grown in popularity in recent years. An estimated five million people participate in "rocking" at least three times a year. Climbing places unique demands on the upper extremity, especially the hands. The flexor tendons and flexor pulleys are prone to sprains and ruptures. Pulley injuries occur in up to 20% of climbers. The A2 pulley of the ring finger is the most frequently injured. Most pulley injuries can be successfully treated with a week of immobilization, followed by a range of motion (ROM) exercises for one week. Isometric training on a finger board can be started once ROM exercises are painless. A return to climbing can be initiated when the climber is able to avoid grip positions that produce pain; however, the closed crimp grip should be avoided at this time. Surgical reconstruction using the technique described by Widstrom is recommended for acute injuries with clinical evidence of bowstringing. Ultrasound and MRI are the current modalities best suited for confirming clinical findings.

  7. 'Pot of Gold' and 'Rotten Rocks'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This false-color image taken by the panoramic camera on the Mars Exploration Rover Spirit shows the rock dubbed 'Pot of Gold' (upper left), located near the base of the 'Columbia Hills' in Gusev Crater. Scientists are intrigued by this unusual-looking, nodule-covered rock and plan to investigate its detailed chemistry in coming sols. This picture was taken on sol 159 (June 14, 2004).

    To the right is a set of rocks referred to as 'Rotten Rocks' for their resemblance to rotting loaves of bread. The insides of these rocks appear to have been eroded, while their outer rinds remain more intact. These outer rinds are reminiscent of those found on rocks at Meridiani Planum's 'Eagle Crater.' This image was captured on sol 158 (June 13, 2004).

  8. Targeting ROCK2 rather than ROCK1 inhibits Ewing sarcoma malignancy

    PubMed Central

    Pinca, Rosa Simona; Manara, Maria Cristina; Chiadini, Valentina; Picci, Piero; Zucchini, Cinzia; Scotlandi, Katia

    2017-01-01

    Understanding the molecular processes characterizing Ewing sarcoma (EWS) cell migration is crucial to highlight novel therapies for patients with disseminated disease. In this study we analyzed the role of ROCK kinases in the regulation of cell migration, growth and differentiation of EWS cells. Overexpression of ROCK promotes invasion and metastasis in many solid tumors. However, the effect of ROCK in EWS has not been extensively investigated. Expression of ROCK1 and ROCK2 was analyzed by western blotting in a representative panel of human EWS cell lines, in comparison with the parameters of in vitro malignancy. We investigated the effects of a ROCK2 specific inhibitor toward those of a pan-ROCK inhibitor on the growth, migration and differentiation of two EWS cell lines. ROCK2 but not ROCK1 expression was found to be associated with in vitro cell migration and anchorage-independent growth capabilities. Exposure of EWS cells to ROCK inhibitors significantly reduced migration and growth, while favoring morphology changes and neural differentiation. These effects were more striking when cells were specifically deprived of ROCK2 activity. Our findings lead to consider ROCK2, rather than ROCK1, as a possible molecular target for the treatment of EWS. PMID:28112365

  9. Metamorphosed ultramafic rocks in east Greenland

    NASA Technical Reports Server (NTRS)

    Kays, M. A.; Dorais, M. J.

    1986-01-01

    The compositional and mineralogical characteristics of Archean ultramafic rocks in Kangerdlugssuaq Fjord are summarized: the first provides information important to understanding the primary character of the rock suite, whereas the latter provides data necessary to determine the conditions of their equilibrium during the latest metamorphism. This information will be of value in determining the affinity of the suite to similar Archean rocks in other areas of the North Atlantic craton.

  10. Reappraisal of hydrocarbon biomarkers in Archean rocks.

    PubMed

    French, Katherine L; Hallmann, Christian; Hope, Janet M; Schoon, Petra L; Zumberge, J Alex; Hoshino, Yosuke; Peters, Carl A; George, Simon C; Love, Gordon D; Brocks, Jochen J; Buick, Roger; Summons, Roger E

    2015-05-12

    Hopanes and steranes found in Archean rocks have been presented as key evidence supporting the early rise of oxygenic photosynthesis and eukaryotes, but the syngeneity of these hydrocarbon biomarkers is controversial. To resolve this debate, we performed a multilaboratory study of new cores from the Pilbara Craton, Australia, that were drilled and sampled using unprecedented hydrocarbon-clean protocols. Hopanes and steranes in rock extracts and hydropyrolysates from these new cores were typically at or below our femtogram detection limit, but when they were detectable, they had total hopane (<37.9 pg per gram of rock) and total sterane (<32.9 pg per gram of rock) concentrations comparable to those measured in blanks and negative control samples. In contrast, hopanes and steranes measured in the exteriors of conventionally drilled and curated rocks of stratigraphic equivalence reach concentrations of 389.5 pg per gram of rock and 1,039 pg per gram of rock, respectively. Polycyclic aromatic hydrocarbons and diamondoids, which exceed blank concentrations, exhibit individual concentrations up to 80 ng per gram of rock in rock extracts and up to 1,000 ng per gram of rock in hydropyrolysates from the ultraclean cores. These results demonstrate that previously studied Archean samples host mixtures of biomarker contaminants and indigenous overmature hydrocarbons. Therefore, existing lipid biomarker evidence cannot be invoked to support the emergence of oxygenic photosynthesis and eukaryotes by ∼ 2.7 billion years ago. Although suitable Proterozoic rocks exist, no currently known Archean strata lie within the appropriate thermal maturity window for syngenetic hydrocarbon biomarker preservation, so future exploration for Archean biomarkers should screen for rocks with milder thermal histories.

  11. Reappraisal of hydrocarbon biomarkers in Archean rocks

    PubMed Central

    French, Katherine L.; Hallmann, Christian; Hope, Janet M.; Schoon, Petra L.; Zumberge, J. Alex; Hoshino, Yosuke; Peters, Carl A.; George, Simon C.; Love, Gordon D.; Brocks, Jochen J.; Buick, Roger; Summons, Roger E.

    2015-01-01

    Hopanes and steranes found in Archean rocks have been presented as key evidence supporting the early rise of oxygenic photosynthesis and eukaryotes, but the syngeneity of these hydrocarbon biomarkers is controversial. To resolve this debate, we performed a multilaboratory study of new cores from the Pilbara Craton, Australia, that were drilled and sampled using unprecedented hydrocarbon-clean protocols. Hopanes and steranes in rock extracts and hydropyrolysates from these new cores were typically at or below our femtogram detection limit, but when they were detectable, they had total hopane (<37.9 pg per gram of rock) and total sterane (<32.9 pg per gram of rock) concentrations comparable to those measured in blanks and negative control samples. In contrast, hopanes and steranes measured in the exteriors of conventionally drilled and curated rocks of stratigraphic equivalence reach concentrations of 389.5 pg per gram of rock and 1,039 pg per gram of rock, respectively. Polycyclic aromatic hydrocarbons and diamondoids, which exceed blank concentrations, exhibit individual concentrations up to 80 ng per gram of rock in rock extracts and up to 1,000 ng per gram of rock in hydropyrolysates from the ultraclean cores. These results demonstrate that previously studied Archean samples host mixtures of biomarker contaminants and indigenous overmature hydrocarbons. Therefore, existing lipid biomarker evidence cannot be invoked to support the emergence of oxygenic photosynthesis and eukaryotes by ∼2.7 billion years ago. Although suitable Proterozoic rocks exist, no currently known Archean strata lie within the appropriate thermal maturity window for syngenetic hydrocarbon biomarker preservation, so future exploration for Archean biomarkers should screen for rocks with milder thermal histories. PMID:25918387

  12. Rock breakage mechanisms with a PDC cutter

    SciTech Connect

    Not Available

    1985-01-01

    Some aspects of chip generation by a polycrystalline diamond compact (PDC) cutter moving through a rock can be understood by examining the shapes of the chips and the fracture patterns in the remaining rock. Data from laboratory experiments have led to general conclusions about the uniformity of chip generation mechanisms in different kinds of rock and about crack nucleation position relative to the cutter tip. 20 refs., 12 figs., 2 tabs.

  13. Reappraisal of hydrocarbon biomarkers in Archean rocks

    NASA Astrophysics Data System (ADS)

    French, Katherine L.; Hallmann, Christian; Hope, Janet M.; Schoon, Petra L.; Zumberge, J. Alex; Hoshino, Yosuke; Peters, Carl A.; George, Simon C.; Love, Gordon D.; Brocks, Jochen J.; Buick, Roger; Summons, Roger E.

    2015-05-01

    Hopanes and steranes found in Archean rocks have been presented as key evidence supporting the early rise of oxygenic photosynthesis and eukaryotes, but the syngeneity of these hydrocarbon biomarkers is controversial. To resolve this debate, we performed a multilaboratory study of new cores from the Pilbara Craton, Australia, that were drilled and sampled using unprecedented hydrocarbon-clean protocols. Hopanes and steranes in rock extracts and hydropyrolysates from these new cores were typically at or below our femtogram detection limit, but when they were detectable, they had total hopane (<37.9 pg per gram of rock) and total sterane (<32.9 pg per gram of rock) concentrations comparable to those measured in blanks and negative control samples. In contrast, hopanes and steranes measured in the exteriors of conventionally drilled and curated rocks of stratigraphic equivalence reach concentrations of 389.5 pg per gram of rock and 1,039 pg per gram of rock, respectively. Polycyclic aromatic hydrocarbons and diamondoids, which exceed blank concentrations, exhibit individual concentrations up to 80 ng per gram of rock in rock extracts and up to 1,000 ng per gram of rock in hydropyrolysates from the ultraclean cores. These results demonstrate that previously studied Archean samples host mixtures of biomarker contaminants and indigenous overmature hydrocarbons. Therefore, existing lipid biomarker evidence cannot be invoked to support the emergence of oxygenic photosynthesis and eukaryotes by ∼2.7 billion years ago. Although suitable Proterozoic rocks exist, no currently known Archean strata lie within the appropriate thermal maturity window for syngenetic hydrocarbon biomarker preservation, so future exploration for Archean biomarkers should screen for rocks with milder thermal histories.

  14. Geochemistry and diagenesis of Miocene lacustrine siliceous sedimentary and pyroclastic rocks, Mytilinii basin, Samos Island, Greece

    USGS Publications Warehouse

    Stamatakis, M.G.; Hein, J.R.; Magganas, A.C.

    1989-01-01

    A Late Miocene non-marine stratigraphic sequence composed of limestone, opal-CT-bearing limestone, porcelanite, marlstone, diatomaceous marlstone, dolomite, and tuffite crops out on eastern Samos Island. This lacustrine sequence is subdivided into the Hora Beds and the underlying Pythagorion Formation. The Hora Beds is overlain by the clastic Mytilinii series which contains Turolian (Late Miocene) mammalian fossils. The lacustrine sequence contains volcanic glass and the silica polymorphs opal-A, opal-CT, and quartz. Volcanic glass predominantly occurs in tuffaceous rocks from the lower and upper parts of the lacustrine sequence. Opal-A (diatom frustules) is confined to layers in the upper part of the Hora Beds. Beds rich in opal-CT underlie those containing opal-A. The occurrence of opal-CT is extensive, encompassing the lower Hora Beds and the sedimentary rocks and tuffs of the Pythagorion Formation. A transition zone between the opal-A and opal-CT zones is identified by X-ray diffraction patterns that are intermediate between those of opal-CT and opal-A, perhaps due to a mixture of the two polymorphs. Diagenesis was not advanced enough for opal-CT to transform to quartz or for volcanic glass to transform to opal-C. Based on geochemical and mineralogical data, we suggest that the rate of diagenetic transformation of opal-A to opal-CT was mainly controlled by the chemistry of pore fluids. Pore fluids were characterized by high salinity, moderately high alkalinity, and high magnesium ion activity. These pore fluid characteristics are indicated by the presence of evaporitic salts (halite, sylvite, niter), high boron content in biogenic silica, and by dolomite in both the opal-A and opal-CT-bearing beds. The absence of authigenic K-feldspar, borosilicates, and zeolites also support these pore fluid characteristics. Additional factors that influenced the rate of silica diagenesis were host rock lithology and the relatively high heat flow in the Aegean region from

  15. Soft Rock Yields Clues to Mars' Past

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site] Figure 1 This image taken by the Mars Exploration Rover Spirit shows the rock outcrop dubbed 'Clovis.' The rock was discovered to be softer than other rocks studied so far at Gusev Crater after the rover easily ground a hole into it with its rock abrasion tool. Spirit's solar panels can be seen in the foreground. This image was taken by the rover's navigation camera on sol 205 (July 31, 2004).

    Elemental Trio Found in 'Clovis' Figure 1 above shows that the interior of the rock dubbed 'Clovis' contains higher concentrations of sulfur, bromine and chlorine than basaltic, or volcanic, rocks studied so far at Gusev Crater. The data were taken by the Mars Exploration Rover Spirit's alpha particle X-ray spectrometer after the rover dug into Clovis with its rock abrasion tool. The findings might indicate that this rock was chemically altered, and that fluids once flowed through the rock depositing these elements.

  16. Evaluation of multiband photography for rock discrimination

    NASA Technical Reports Server (NTRS)

    Raines, G. L.

    1974-01-01

    An evaluation is presented of the multiband photography concept that tonal differences between rock formations on aerial photography can be improved through the selection of the appropriate bands. The concept involves: (1) acquiring band reference data for the rocks being considered; (2) selecting the best combination of bands to discriminate the rocks using these reference data; (3) acquiring aerial photography using these selected bands; and (4) extracting the desired geologic information in an optimum manner. The test site geology and rock reflectance are discussed in detail. The evaluation found that the differences in contrast ratios are not statistically significant, and the spectral information in different bands is not advantageous.

  17. Rock Art of the Greater Southwest

    NASA Astrophysics Data System (ADS)

    Krupp, Edwin C.

    Archaeoastronomical studies in the American Southwest began in 1955 with recognition of what seemed to be pictorial eyewitness records of the Crab supernova of 1054 AD In time, reports of seasonally significant light-and-shadow effects on rock art and associations of rock art with astronomical alignments also emerged. Most astronomical rock art studies remained problematic, however, because criteria for proof of ancient intent were elusive. Disciplined methods for assessing cultural function were difficult to develop, but review of ethnographically documented astronomical traditions of California Indians and of Indians in the American Southwest subsequently increased confidence in the value of some astronomical rock art initiatives.

  18. Rayleigh wave studies in lunar rocks.

    NASA Technical Reports Server (NTRS)

    Tittmann, B. R.

    1972-01-01

    An ultrasonic surface wave technique described by the author (1971) is used to verify a hypothesis that links the seismic wave propagation velocities in lunar crust, much too low as compared to those on earth, to the extensive fracturing of lunar rock in the absence of liquids and gases which changed drastically the elastic and inelastic properties of lunar rock. Measurements on lunar rock samples and synthetic analogs suggest that the presence of microfractures have influence on both the wave velocity and Q factor in lunar rocks.

  19. Crack initiation around prestressed rock bolts

    NASA Astrophysics Data System (ADS)

    Wijk, G.

    1982-07-01

    The stress fields in the rock in the immediate vicinities of the ends of prestressed rock bolts are considered. In particular, the tensile stresses that are likely to initiate cracks are studies. A fracture mechanics analysis shows that if cracks are initiated they will normally not be extended more than a few bore hole diameters and cause negligable reduction of the tensile force in the rock bolts. It is suggested that the initiated cracks can be considerably extended by blasting activities in the neighborhood and accordingly cause loss of bolt tension. If so retensioning of the rock bolts is quite meaningless.

  20. Meteorite Linked to Rock at Meridiani

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This meteorite, a basalt lava rock nearly indistinguishable from many Earth rocks, provided the first strong proof that meteorites could come from Mars. Originally weighing nearly 8 kilograms (17.6 pounds), it was collected in 1979 in the Elephant Moraine area of Antarctica. The side of the cube at the lower left in this image measures 1 centimeter (0.4 inches).

    This picture shows a sawn face of this fine-grained gray rock. (The vertical stripes are saw marks.) The black patches in the rock are melted rock, or glass, formed when a large meteorite hit Mars near the rock. The meteorite impact probably threw this rock, dubbed 'EETA79001,' off Mars and toward Antarctica on Earth. The black glass contains traces of martian atmosphere gases.

    The Mars Exploration Rover Opportunity has discovered that a rock dubbed 'Bounce' at Meridiani Planum has a very similar mineral composition to this meteorite and likely shares common origins. Bounce itself is thought to have originated outside the area surrounding Opportunity's landing site; an impact or collision likely threw the rock away from its primary home.

  1. Dynamic tensile strength of lunar rock types

    NASA Technical Reports Server (NTRS)

    Cohn, S. N.; Ahrens, T. J.

    1981-01-01

    The dynamic tensile strength of four rocks are determined. A flat plate impact experiment is employed to generate approximately one-microsecond-duration tensile stress pulses in rock samples by superposing rarefaction waves to induce fracture. It is noted that the effect of chemical weathering and other factors has not been explicitly studied. The given tensile strengths are based on a series of experiments on each rock where determination of incipient spallation is made by terminal microscopic examination. The data are generally consistent with previous determinations, at least one of which was for a significantly chemically altered but physically coherent rock.

  2. Impact of Rock Bolts on Seepage

    SciTech Connect

    F. C. Ahlers

    2001-06-01

    Characterization of seepage into drifts in unsaturated fractured tuff is a key factor for assessing the long-term viability of the proposed high level nuclear waste repository at Yucca Mountain. Rock bolts are among the methods proposed for ground control in the emplacement drifts. They may provide a conduit whereby percolating water that would otherwise bypass the drift will seep into the drift. The objective of this study is to assess the impact that the use of rock bolts may have on seepage. The impact of rock bolts on seepage is studied using a numerical model that is finely discretized around the rock bolt. There are several sources of uncertainty and variability with respect to the flow system around the drift and rock bolt. There is uncertainty about the capillary strength of the fractures around the drift. There is also uncertainty about how the permeability and capillary strength of the grout used to cement the steel rock bolts into the bolt holes will change over time. There is variability expected in the percolation rates incident upon the drifts depending on location. The uncertainty and variability of these parameters are approached by evaluating the rock bolt impact over a range of values for several model parameters. It is also important to consider where the last fracture capable of carrying flow away from the rock bolt intersects the rock bolt. Three models are used where the last fracture is 0, 10 and 50 cm above the drift.

  3. Opaque mineralogy - Apollo 17, rock 75035

    NASA Technical Reports Server (NTRS)

    Meyer, H. O. A.; Boctor, N. Z.

    1974-01-01

    Rock 75035 is a medium-grained, holocrystalline, subophitic ilmenite basalt collected from the rim of Camelot Crater, and is believed to represent the subfloor basalts of the Taurus-Littrow valley. The rock consists of the major minerals pyroxene (45%), plagioclase (31%), and ilmenite (17%). Minor minerals include cristobalite (about 5%), troilite, native Fe, tranquillityite, baddeleyite, zirconolite, and rare ulvospinel. No olivine or armalcolite was observed in the specimen 75035,76. Mineralogically and chemically, as well as in age, this rock is similar to others collected from Camelot and other stations during the Apollo 17 mission. These rocks are almost identical to the Type B ilmenite basalts of Mare Tranquillitatis.

  4. Spirit Discovers New Class of Igneous Rocks

    NASA Technical Reports Server (NTRS)

    2006-01-01

    During the past two-and-a-half years of traversing the central part of Gusev Crater, NASA's Mars Exploration Rover Spirit has analyzed the brushed and ground-into surfaces of multiple rocks using the alpha particle X-ray spectrometer, which measures the abundance of major chemical elements. In the process, Spirit has documented the first example of a particular kind of volcanic region on Mars known as an alkaline igneous province. The word alkaline refers to the abundance of sodium and potassium, two major rock-forming elements from the alkali metals on the left-hand side of the periodic table.

    All of the relatively unaltered rocks -- those least changed by wind, water, freezing, or other weathering agents -- examined by Spirit have been igneous, meaning that they crystallized from molten magmas. One way geologists classify igneous rocks is by looking at the amount of potassium and sodium relative to the amount of silica, the most abundant rock-forming mineral on Earth. In the case of volcanic rocks, the amount of silica present gives scientists clues to the kind of volcanism that occurred, while the amounts of potassium and sodium provide clues about the history of the rock. Rocks with more silica tend to erupt explosively. Higher contents of potassium and sodium, as seen in alkaline rocks like those at Gusev, may indicate partial melting of magma at higher pressure, that is, deeper in the Martian mantle. The abundance of potassium and sodium determines the kinds of minerals that make up igneous rocks. If igneous rocks have enough silica, potassium and sodium always bond with the silica to form certain minerals.

    The Gusev rocks define a new chemical category not previously seen on Mars, as shown in this diagram plotting alkalis versus silica, compiled by University of Tennessee geologist Harry McSween. The abbreviations 'Na2O' and 'K2O' refer to oxides of sodium and potassium. The abbreviation 'SiO2' refers to silica. The abbreviation 'wt

  5. Geologic framework of pre-Cretaceous rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico

    USGS Publications Warehouse

    Condon, Steven M.

    1992-01-01

    This report is a discussion and summary of Jurassic and older rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico, and is based on analysis of geophysical logs and observations of outcrops. The Reservation, which is located in the northern San Juan Basin, has been the site of deposition of sediments for much of the Phanerozoic. Geologic times represented on the Reservation are the Precambrian, Cambrian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary, and Quaternary. Rocks of Ordovician and Silurian age have not been reported in this region. Thicknesses of pre-Cretaceous sedimentary rocks range from about 750 feet (229 meters) on the Archuleta arch, east of the Reservation, to more than 8,300 feet (2,530 meters) just northwest of the Reservation. About 5,500 feet (1,676 meters) of pre-Cretaceous sedimentary rocks occur in the central part of the Reservation, near Ignacio. At Ignacio the top of the Jurassic lies at a depth of 7,600 feet (2,316 meters) below the surface, which is composed of Tertiary rocks. As much as 2,500 feet (762 meters) of Tertiary rocks occur in the area. More than 10,000 feet (3,048 meters) of Cretaceous and younger rocks, and 15,600 feet (4,755 meters) of all Phanerozoic sedimentary rocks occur in the vicinity of the Reservation. In the early Paleozoic the area that includes the Southern Ute Reservation was on the stable western shelf of the craton. During this time sediments that compose the following shallow-marine clastic and carbonate rocks were deposited: the Upper Cambrian Ignacio Quartzite (0-150 feet; 0-46 meters), Upper Devonian Elbert Formation (50-200 feet; 15-61 meters), Upper Devonian Ouray Limestone (10-75 feet; 3-23 meters), and Mississippian Leadville Limestone (0-250 feet; 0-76 meters). Mixed carbonate and clastic deposition, which was punctuated by a unique episode of deposition of evaporite sediments, continued through

  6. Elastic Properties of Sedimentary Rocks

    NASA Astrophysics Data System (ADS)

    Melendez Martinez, Jaime

    Sedimentary rocks are an important research topic since such rocks are associated to sources of ground water as well as oil, gas, and mineral reservoirs. In this work, elastic and physical properties of a variety of sedimentary samples that include glacial sediments, carbonates, shales, one evaporite, and one argillite from a variety of locations are investigated. Assuming vertical transverse isotropy, ultrasonic compressional- and shear-waves (at 1 MHz central frequency) were measured as a function of confining pressure on all samples with the exception of glacial samples which were tested assuming isotropy. Tensile strength tests (Brazilian test) were also carried out on selected glacial samples and, in addition, static-train measurements were conducted on shales and argillite samples. Lithological and textural features of samples were obtained through thin section techniques, scanning electron microscopy images and micro-tomography images. X-ray diffraction and X-Ray fluorescence provided the mineralogical oxides content information. Porosity, density, and pore structure were studied by using a mercury intrusion porosimeter and a helium pycnometer. The wide range of porosities of the studied samples (ranging from a minimum of 1% for shales to a maximum 45% for some glacial sediments) influence the measured velocities since high porosity sample shows an noticeable velocity increment as confining pressure increases as a consequence of closure of microcracks and pores, unlike low porosity samples where increment is quasi-lineal. Implementation of Gassmann's relation to ultrasonic velocities obtained from glacial samples has negligible impact on them when assuming water saturated samples, which suggests that state of saturation it is no so important in defining such velocities and instead they are mainly frame-controlled. On the other hand, velocities measured on carbonate and evaporite samples show that samples are at best weak anisotropic, thus the intrinsic

  7. Some influences of rock strength and strain rate on propagation of rock avalanches

    NASA Astrophysics Data System (ADS)

    Bowman, Elisabeth; Rait, Kim

    2016-04-01

    Rock avalanches are extreme and destructive mass movements in which large volumes of rock (typically >1 million cubic metres) travel at high speeds, covering large distances, and the occurrence of which is highly unpredictable. The "size effect" in rock avalanches, whereby those with larger volumes produce greater spreading efficiency (as defined by an increase in normalised runout) or lower farboschung angle (defined as the tangent of the ratio of fall height to runout length), is well known. Studies have shown that rock strength is a controlling factor in the mobility of rock avalanches - that is, mass movements involving lower strength rock are generally found to produce greater mobility as evidenced by the spread of deposits or low farboschung angle. However, there are conflicting ideas as to how and why this influence is manifested. This paper discusses different theories of rock comminution in light of numerical simulations of rock clasts undergoing normal and shear induced loading, experimental work on rock avalanche behaviour, and dynamic fracture mechanics. In doing so, we introduce the idea of thresholds of strain rate for the production of dynamic fragmentation (as opposed to pseudo-static clast crushing) that are based, inter alia, on static rock strength. To do this, we refer to data from physical models using rock analogue materials, field data on chalk cliff collapses, and field statistics from documented rock avalanches. The roles of normal and shear loading and loading rate within a rock avalanche are examined numerically using 3D Discrete Element Method models of rock clasts loaded to failure. Results may help to reconcile the observations that large rock avalanches in stronger materials tend not to fragment as much as those in weaker materials and also possess lower mobility, while small cliff collapses (typically > 1000 cubic metres) in weak chalk can exhibit rock avalanche-like behaviour at much smaller volumes.

  8. Abiogenic methanogenesis in crystalline rocks

    SciTech Connect

    Lollar, B.S.; Frape, S.K. ); Weise, S.M. , Neuherberg ); Fritz, P. ); Macko, S.A. ); Welhan, J.A. )

    1993-12-01

    Isotopically anomalous CH[sub 4]-rich gas deposits are found in mining sites on both the Canadian and Fennoscandian shields. With [delta][sup 13]C[sub CH4] values from -22.4 to -48.5% and [delta]D[sub CH4] values from -133 to -372%, these methane deposits cannot be accounted for by conventional processes for bacterial or thermogenic methanogenesis. Compositionally the gases are similar to other CH[sub 4]-rich gas occurrences found in Canadian and Fennoscandian shield rocks. However, the isotopically anomalous gases of this study are characterized by unexpectedly high concentrations of H[sub 2] gas, ranging from several volume percent up to 30 vol%. The H[sub 2] gases are consistently depleted in the heavy isotope, with [delta]D[sub H[sub 2

  9. Manufactured caverns in carbonate rock

    DOEpatents

    Bruce, David A.; Falta, Ronald W.; Castle, James W.; Murdoch, Lawrence C.

    2007-01-02

    Disclosed is a process for manufacturing underground caverns suitable in one embodiment for storage of large volumes of gaseous or liquid materials. The method is an acid dissolution process that can be utilized to form caverns in carbonate rock formations. The caverns can be used to store large quantities of materials near transportation facilities or destination markets. The caverns can be used for storage of materials including fossil fuels, such as natural gas, refined products formed from fossil fuels, or waste materials, such as hazardous waste materials. The caverns can also be utilized for applications involving human access such as recreation or research. The method can also be utilized to form calcium chloride as a by-product of the cavern formation process.

  10. On wettability of shale rocks.

    PubMed

    Roshan, H; Al-Yaseri, A Z; Sarmadivaleh, M; Iglauer, S

    2016-08-01

    The low recovery of hydraulic fracturing fluid in unconventional shale reservoirs has been in the centre of attention from both technical and environmental perspectives in the last decade. One explanation for the loss of hydraulic fracturing fluid is fluid uptake by the shale matrix; where capillarity is the dominant process controlling this uptake. Detailed understanding of the rock wettability is thus an essential step in analysis of loss of the hydraulic fracturing fluid in shale reservoirs, especially at reservoir conditions. We therefore performed a suit of contact angle measurements on a shale sample with oil and aqueous ionic solutions, and tested the influence of different ion types (NaCl, KCl, MgCl2, CaCl2), concentrations (0.1, 0.5 and 1M), pressures (0.1, 10 and 20MPa) and temperatures (35 and 70°C). Furthermore, a physical model was developed based on the diffuse double layer theory to provide a framework for the observed experimental data. Our results show that the water contact angle for bivalent ions is larger than for monovalent ions; and that the contact angle (of both oil and different aqueous ionic solutions) increases with increase in pressure and/or temperature; these increases are more pronounced at higher ionic concentrations. Finally, the developed model correctly predicted the influence of each tested variable on contact angle. Knowing contact angle and therefore wettability, the contribution of the capillary process in terms of water uptake into shale rocks and the possible impairment of hydrocarbon production due to such uptake can be quantified.

  11. Application of advanced reservoir characterization, simulation, and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, west Texas (Delaware Basin). Annual progress report, March 31, 1995--March 31, 1996

    SciTech Connect

    Dutton, S.P.; Hovorka, S.D.; Cole, A.G.

    1996-08-01

    The objective of this Class III project is to demonstrate that detailed reservoir characterization of clastic reservoirs in basinal sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover more of the original oil in place by strategic infill-well placement and geologically based field development. Reservoirs in the Delaware Mountain Group have low producibility (average recovery <14 percent of the original oil in place) because of a high degree of vertical and lateral heterogeneity caused by depositional processes and post-depositional diagenetic modification. Detailed correlations of the Ramsey sandstone reservoirs in Geraldine Ford field suggest that lateral sandstone continuity is less than interpreted by previous studies. The degree of lateral heterogeneity in the reservoir sandstones suggests that they were deposited by eolian-derived turbidites. According to the eolian-derived turbidite model, sand dunes migrated across the exposed shelf to the shelf break during sea-level lowstands and provided well sorted sand for turbidity currents or grain flows into the deep basin.

  12. Types of secondary porosity of carbonate rocks in injection and test wells in southern peninsular Florida

    USGS Publications Warehouse

    Duerr, A.D.

    1995-01-01

    The types of secondary porosity present in carbonate injection intervals and in the overlying carbonate rocks were determined at 11 injection well sites and 3 test well sites in southern peninsular Florida. The hydrogeologic system consists of a thick sequence of carbonate rocks overlain by clastic deposits. Principal hydrogeologic units are the surficial aquifer system, the intermediate aquifer system or the intermediate confining unit,the Floridan aquifer system, and the sub-Floridan confining unit.The concept of apparent secondary porosity was used in this study because the secondary porosity features observed in a borehole television survey could have been caused by geologic processes as well as by drilling activities. The secondary porosity features identified in a television survey were evaluated using driller's comments and caliper, flowmeter, and temperature logs. Borehole intervals that produced or received detectable amounts of flow, as shown by flowmeter and temperature logs, provided evidence that the secondary porosity of the interval was spatially distributed and interconnected beyond the immediate vicinity of a borehole and, thus, was related to geologic processes. Features associated with interconnected secondary porosity were identified as effective secondary porosity. Fracture porosity was identified as the most common type of effective secondary porosity and was observed predominantly in dolomite and dolomitic limestone. Cavity porosity was the least common type of effective secondary porosity at the study sites. In fact, of the more than 17,500 feet of borehole studied a total of only three cavities constituting effective secondary porosity were identified at only two sites. These cavities were detected in dolomite rocks. Most apparent cavities were caused by drilling-induced collapse of naturally fractured borehole walls. Also, fractures usually were observed above and below cavities. The majority of vugs observed in the television surveys did

  13. Organic metamorphism in the Lower Mississippian-Upper Devonian Bakken shales. Part 1: Rock-Eval pyrolysis and vitrinite reflectance.

    USGS Publications Warehouse

    Price, L.C.; Daws, T.; Pawlewicz, M.

    1986-01-01

    The Williston basin is an intracratonic basin extending across parts of several states, principally North Dakota, on the US/Canadian frontier. A sequence of up to 16 000 ft of Phanerozoic rocks exists in the basin; the Bakken formation is a relatively thin clastic unit composed of three members, of which the middle one is a black shale. Both core chip and cutting chip samples from a series of widely-distributed well locations were taken for laboratory analysis. Pyrolysis data showed 'wide variations' in maturity indices in samples from equivalent depths at different well locations. This suggests that a number of different palaeoheat-flow regimes have existed in the basin, resulting in the optimization of hydrocarbon formation processes at varying depths at different localities. The vitrinite reflectance profiles presented illustrate the expected trend of linearly-increasing maturity with depth to around 6500 ft. Between 6700 and 10 000 ft, however, this trend is interrupted by two 'reversals'. It is suggested that these reversals are due to suppression of the vitrinite reflectance values in samples with high concentrations of H-rich organic matter, and that they may therefore be associated with transitions from 'terrestrial-derived' to marine-depositional conditions. Consequently, the precise identification of the thresholds of intense hydrocarbon generation within the basin is problematic.-J.M.H.

  14. Making "Rock Hounds" of "City Slickers."

    ERIC Educational Resources Information Center

    Fazio, Rosario P.; Nye, Osborne

    1980-01-01

    Described are ways in which urban "rocks" (building stones, curbstones, sidewalks, etc.) can be used as resources for earth science teachers. Discussed are such activities as: classifying buildings according to rock type and mineral composition, extrapolating geologic history by examining common building materials, economics of stone industry, and…

  15. ROCK inhibition prevents early mouse embryo development.

    PubMed

    Duan, Xing; Chen, Kun-Lin; Zhang, Yu; Cui, Xiang-Shun; Kim, Nam-Hyung; Sun, Shao-Chen

    2014-08-01

    ROCK is a Rho-GTPase effector that is important for actin assembly and is involved in various cellular functions, including cell contraction, migration, motility, and tumor cell invasion. In this study, we investigated ROCK expression and function during early mouse embryo development. Inhibiting ROCK by Y-27632 treatment at the zygote stage resulted in first cleavage failure, and most embryos failed to develop to the 8-cell stage. When adding Y-27632 at the 8-cell stage, embryos failed to undergo compaction and could not develop into blastocysts. In addition, fluorescence staining intensity analysis indicated that actin expression at blastomere membranes was significantly reduced. After ROCK inhibition, two or more nuclei were observed in a cell, which indicated possible cytokinesis failure. Moreover, after ROCK inhibition with Y-27632, the phosphorylation levels of LIMK1/2, a downstream molecule of ROCK, were decreased at blastomere membranes. Thus, our results showed conserved roles for ROCK in this mammalian embryo model and indicated that a ROCK-LIMK1/2-actin pathway might regulate cleavage and blastocyst formation during early mouse embryo development.

  16. Rheology of rock glaciers: a preliminary assessment

    SciTech Connect

    Giardino, J.R.; Vitek, J.D.; Hoskins, E.R.

    1985-01-01

    Movement of rock debris under the influence of gravity, i.e., mass movement, generates a range of phenomena from soil creep, through solifluction,debris flows and rock glaciers to rock falls. Whereas the resultant forms of these phenomena are different, common elements in the mechanics of movement are utilized in the basic interpretation of the processes of formation. Measurements of morphologic variables provide data for deductive analyses of processes that operate too slowly to observe or for processes that generated relict phenomena. External and internal characteristics or rock glacier morphometry and measured rates of motion serve as the basis for the development of a rheological model to explain phenomena classified as rock glaciers. A rock glacier in the Sangre de Cristo Mountains of Southern Colorado, which exhibits a large number of ridges and furrows and lichen bare fronts of lobes, suggests present day movement. A strain-net established on the surface provides evidence of movement characteristics. These data plus morphologic and fabric data suggest two rheological models to explain the flow of this rock glacier. Model one is based upon perfect plastic flow and model two is based upon stratified fluid movement with viscosity changing with depth. These models permit a better understanding of the movement mechanics and demonstrate that catastrophic events and slow creep contribute to the morphologic characteristics of this rock glacier.

  17. Rock Music and Korean Adolescent's Antisocial Behavior.

    ERIC Educational Resources Information Center

    Kim, Inkyung; Kwak, Keumjoo; Chang, Geunyoung; Yang, Jinyoung

    The relationship between rock music preference and antisocial behavior among Korean adolescents was examined. The Korean versions of the Sensation Seeking Scale and the Antisocial Behavior Checklist were used to measure sensation seeking motivation and delinquency. Adolescents (N=1,079) were categorized as "rock/metal,""dance,"…

  18. Rock avalanches caused by earthquakes: source characteristics.

    PubMed

    Keefer, D K

    1984-03-23

    Study of a worldwide sample of historical earthquakes showed that slopes most susceptible to catastrophic rock avalanches were higher than 150 meters and steeper than 25 degrees. The slopes were undercut by fluvial or glacial erosion, were composed of intensely fractured rock, and exhibited at least one other indicator of low strength or potential instability.

  19. High-temperature carbidization of carboniferous rocks

    NASA Astrophysics Data System (ADS)

    Goldin, B. A.; Grass, V. E.; Nadutkin, A. V.; Nazarova, L. Yu.

    2009-08-01

    Processes of thermal metamorphism of carboniferous rocks have been studied experimentally. The conditions of high-temperature interaction of shungite carbon with components of the contained rocks, leading to formation of carbide compounds, have been determined. The results of this investigation contribute to the works on searching for new raw material for prospective material production.

  20. Extracting Information from Folds in Rocks.

    ERIC Educational Resources Information Center

    Hudleston, Peter John

    1986-01-01

    Describes the three processes of folding in rocks: buckling, bending, and passive folding. Discusses how geometrical properties and strain distributions help to identify which processes produce natural folds, and also provides information about the mechanical properties of rocks, and the sense of shear in shear zones. (TW)

  1. Hot-dry-rock feasibility study

    SciTech Connect

    Not Available

    1981-08-01

    The hot-dry-rock project tasks are covered as follows: hot-dry-rock reservoir; generation facilities; water resources; transmission requirements; environmental issues; government and community institutional factors; leasing, ownership and management of facilities; regulations, permits, and laws; and financial considerations. (MHR)

  2. Rock Cycle. K-6 Science Curriculum.

    ERIC Educational Resources Information Center

    Blueford, J. R.; And Others

    Rock Cycle is one of the units of a K-6 unified science curriculum program. The unit consists of four organizing sub-themes: (1) chemistry (introducing the topics of matter, elements, compounds, and chemical bonding); (2) characteristics (presenting hands-on activities with rocks and minerals); (3) minerals (emphasizing the aesthetic and economic…

  3. Mineral resource of the month: phosphate rock

    USGS Publications Warehouse

    Jasinski, Stephen M.

    2007-01-01

    Phosphate rock minerals provide the only significant global resources of phosphorus, which is an essential element for plant and animal nutrition. Phosphate rock is used primarily as a principal component of nitrogen-phosphorus-potassium fertilizers, but also to produce elemental phosphorus and animal feed.

  4. Preparation for Moving a Rock on Mars

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The robotic arm on NASA's Phoenix Mars Lander enlarged a trench beside a rock called 'Headless' during the mission's 115th Martian day (Sept. 20, 2008) in preparation for sliding the rock into the trench. The lander's Surface Stereo Imager took this image later that afternoon, showing the enlarged trench and the rock.

    The robotic arm successfully moved the rock two days later.

    The Phoenix science team sought to move the rock in order to study the soil and the depth to subsurface ice underneath where the rock had been.

    Headless is about the size and shape of a VHS videotape. The trench, called 'Neverland,' was excavated to about 3 centimeters (1.2 inches) deep near the rock. The ground surface between the rock and the lip of the trench slopes downward about 3 degrees toward the trench.

    This image was taken at about 4:35 p.m., local solar time on Mars. The view is to the north northeast of the lander.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  5. Astronomy and Rock Art in Mexico

    NASA Astrophysics Data System (ADS)

    Murray, William Breen

    Many traditions involving sky observation among the Amerindian cultures of prehistoric Mexico are associated with rock art. This relation appears in the form of iconographic representations of celestial objects, graphic images which are culturally associated with these sky objects, and the location and orientation of rock art images within the natural landscape.

  6. Statistical pattern recognition for rock joint images

    NASA Astrophysics Data System (ADS)

    Wang, Weixing; Bin, Cui

    2005-10-01

    As a cooperation project between Sweden and China, we sampled a number of rock specimens for analyze rock fracture network by optical image technique. The samples are resin injected, in which way; opened fractures can be seen clearly by means of UV (Ultraviolet) light illumination. In the study period, Recognition of rock fractures is crucial in many rock engineering applications. In order to successfully applying automatic image processing techniques for the problem of automatic (or semi-automatic) rock fracture detection and description, the key (and hardest task) is the automatic detection of fractures robustly in images. When statistical pattern recognition is used to segment a rock joint color image, features of different samples can be learned first, then, each pixel of the image is classified by these features. As the testing result showing, an attribute rock fracture image is segmented satisfactorily by using this way. The method can be widely used for other complicated images too. In this paper, Kernel Fisher discrimination (KFD) is employed to construct a statistical pattern recognition classifier. KFD can transform nonlinear discrimination in an attribute space with high dimension, into linear discrimination in a feature space with low dimension. While one needs not know the detailed mapping form from attribute space to feature space in the process of transformation. It is proved that this method performs well by segmenting complicated rock joint color images.

  7. RockIT: A Graphical Program for Labeling and Analyzing Rock Scenes

    NASA Astrophysics Data System (ADS)

    Bornstein, B.; Castano, A.; Anderson, R. C.; Castano, R.

    2005-12-01

    We have developed the Rock Identification Toolkit (RockIT), a mature, cross-platform, graphical program designed to help geologists rapidly and accurately label rocks and particles in images. As images are labeled, RockIT reports both individual rock (or particle) statistics and overall scene statistics. Basic statistics include 2D rock (image) area and average albedo. A more involved set of statistics uses a direct least squares technique to fit a rock trace to an ellipse and report the semimajor and semiminor axes, orientation, eccentricity, and quality of fit. When range data (e.g. derived from a stereo image pair) is available, RockIT provides both 3D rock size and overall scene area estimates. All statistics may be manipulated interactively and later exported to plain, tab-delimited text for easy import into tools like Excel or Matlab for further sophisticated analysis, summarization, and visualization. RockIT can read and display both image and, when available, corresponding range data. Although it supports several popular graphics file formats (e.g. JPEG, TIFF, etc.) our focus has been on more domain-specific file formats, particularly the MER Planetary Data System (PDS) formats. Images, once displayed, may be enhanced in continually, in real-time, throughout the analysis process. Examples of image enhancement include increasing or decreasing brightness and contrast, performing simple min/max intensity normalizations or more complicated histogram equalizations. Several scientists and students at JPL, NASA, Cornell, and PSI use RockIT to identify and characterize rock shape, size, and distribution in MER microscopic imager and panoramic images. Recently, Golombek et al. (2005) used RockIT to compare rock size distributions and calculate cumulative fractional area coverage at several locations along the Spirit traverse. We have a laptop computer running RockIT to demonstrate its capabilities and allow people to experiment on their own.

  8. Distributed snow and rock temperature modelling in steep rock walls using Alpine3D

    NASA Astrophysics Data System (ADS)

    Haberkorn, Anna; Wever, Nander; Hoelzle, Martin; Phillips, Marcia; Kenner, Robert; Bavay, Mathias; Lehning, Michael

    2017-02-01

    In this study we modelled the influence of the spatially and temporally heterogeneous snow cover on the surface energy balance and thus on rock temperatures in two rugged, steep rock walls on the Gemsstock ridge in the central Swiss Alps. The heterogeneous snow depth distribution in the rock walls was introduced to the distributed, process-based energy balance model Alpine3D with a precipitation scaling method based on snow depth data measured by terrestrial laser scanning. The influence of the snow cover on rock temperatures was investigated by comparing a snow-covered model scenario (precipitation input provided by precipitation scaling) with a snow-free (zero precipitation input) one. Model uncertainties are discussed and evaluated at both the point and spatial scales against 22 near-surface rock temperature measurements and high-resolution snow depth data from winter terrestrial laser scans.In the rough rock walls, the heterogeneously distributed snow cover was moderately well reproduced by Alpine3D with mean absolute errors ranging between 0.31 and 0.81 m. However, snow cover duration was reproduced well and, consequently, near-surface rock temperatures were modelled convincingly. Uncertainties in rock temperature modelling were found to be around 1.6 °C. Errors in snow cover modelling and hence in rock temperature simulations are explained by inadequate snow settlement due to linear precipitation scaling, missing lateral heat fluxes in the rock, and by errors caused by interpolation of shortwave radiation, wind and air temperature into the rock walls.Mean annual near-surface rock temperature increases were both measured and modelled in the steep rock walls as a consequence of a thick, long-lasting snow cover. Rock temperatures were 1.3-2.5 °C higher in the shaded and sunny rock walls, while comparing snow-covered to snow-free simulations. This helps to assess the potential error made in ground temperature modelling when neglecting snow in steep bedrock.

  9. 5. Photograph of a photograph in possession of Rock Island ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. WEST AND SOUTH ELEVATIONS, BEFORE REMOVAL OF CHIMNEY, FINIALS, GINGERBREAD, AND VARIEGATED SLATE ROOFING. DATED C. 1876. - Rock Island Arsenal, Building No. 321, Rodman Avenue & Rock Island Avenue, Rock Island, Rock Island County, IL

  10. A review of Alpine tectonics in Portugal: Foreland detachment in basement and cover rocks

    NASA Astrophysics Data System (ADS)

    Ribeiro, A.; Kullberg, M. C.; Kullberg, J. C.; Manuppella, G.; Phipps, S.

    1990-12-01

    The Alpine foreland in Portugal was deformed by compressional tectonism during the Miocene. In the NNE-SSW oriented Lusitanian Basin, most folds and thrusts in the Meso-Cenozoic cover are oriented ENE-WSW, parallel to the Alpine front in the Betic Cordillera, and verge towards the north-northwest and south-southeast. The thrusts are connected by lateral ramps: most of these are oriented NNE-SSW to N-S and show sinistral movement, and some are transpressional. The lateral ramps result from reactivation of older extensional faults related to crustal thinning of the continental margin. In the E-W oriented Algarve Basin a simpler basin inversion occurred, with older E-W normal faults reactivated as essentially pure thrusts. In both basins Alpine structures formed above décollements in the Hettangian evaporite-clastic complex. Variscan basement was also deformed by ENE-WSW reverse faults during Miocene time. The similarity in orientation and style of the basement structures to those in the cover suggests that they also occurred by detachment, but their larger scale indicates that the detachment is deep and involves much of the crust. Thus, we interpret the Central Cordillera, in which basement rocks are thrust over Miocene sediments on both sides, as a "pop-up" of crustal scale, elevated above downward-flattening faults that dip towards each other and merge into a single deep detachment. Alpine structures in the Iberian foreland are therefore similar in structural style to those of the Appalachian and Laramide forelands of North America and the Alpine foreland of northwest Europe.

  11. Kinetics of crystallization of igneous rocks

    SciTech Connect

    Kirkpatrick, R.J.

    1981-01-01

    The geochemistry of igneous rocks is discussed, with the primary objectives of bringing together the theories underlying the kinetics of crystallization of igneous rocks and illustrating the use of these theories in understanding experimental and observational data. The primary purpose of the chapter is to introduce current thinking about the kinetics of igneous rocks and to provide a basis for understanding other work. A basic assumption made in the discussion is that the rate of any chemical reaction, including the crystallization of igneous rocks, is zero at equilibrium and proceeds at a finite rate only at a finite deviation from equilibrium. As such, an understanding of the processes operating in igneous rocks requires an understanding of how deviation from equilibrium affects the rates and mechanisms of the processes occurring during crystallization. These processes are detailed, with special emphasis given to nucleation and crystal growth. (JMT)

  12. First Grinding of a Rock on Mars

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The round, shallow depression in this image resulted from history's first grinding of a rock on Mars. The rock abrasion tool on NASA's Spirit rover ground off the surface of a patch 45.5 millimeters (1.8 inches) in diameter on a rock called Adirondack during Spirit's 34th sol on Mars, Feb. 6, 2004. The hole is 2.65 millimeters (0.1 inch) deep, exposing fresh interior material of the rock for close inspection with the rover's microscopic imager and two spectrometers on the robotic arm. This image was taken by Spirit's panoramic camera, providing a quick visual check of the success of the grinding. The rock abrasion tools on both Mars Exploration Rovers were supplied by Honeybee Robotics, New York, N.Y.

  13. Apollo 16 rocks - Petrology and classification.

    NASA Technical Reports Server (NTRS)

    Wilshire, H. G.; Stuart-Alexander, D. E.; Jackson, E. D.

    1973-01-01

    The Apollo 16 rocks are classified in three broad intergradational groups: (1) crystalline rocks, subdivided into igneous rocks and metaclastic rocks, (2) glass, and (3) breccias, which are subdivided into five groups on the basis of clast and matrix colors. Most of the rocks were derived by impact brecciation of an anorthosite-norite suite but may represent ejecta from more than one major basin. First-cycle breccias are believed to have consisted of clasts of crushed anorthosite-norite in a fine-grained partly fused matrix with a chemical composition similar to that of the clasts. Most of the other recognized breccia types could have been produced by rebrecciation of first-cycle breccias.

  14. Evidence of Ancient Blisters in Rocks

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image from the panoramic camera on the Mars Exploration Rover Spirit shows scoriaceous rocks (rocks containing holes or cavities) on the ground, as well as a transition from rocky terrain (foreground) to smoother terrain (background). Spirit is heading toward the smoother terrain on its way to the 'Columbia Hills.' The holes in some of the rocks may have resulted from 'blisters' formed by water vapor as it escaped lava. This indicates that the rocks were chilled atop an ancient lava flow. Porous rocks such as these, now appearing in abundance, have not been seen since early in the mission. Scientists believe they may have been covered by crater ejecta. This image was taken on sol 110 (April 24, 2004) at a region dubbed 'site 35.'

  15. Lithofacies and palynostratigraphy of some Cretaceous and Paleocene rocks, Surghar and Salt Range coal fields, northern Pakistan

    USGS Publications Warehouse

    Warwick, Peter D.; Javed, Shahid; Mashhadi, S. Tahir A.; Shakoor, Tariq; Khan, Asrar M.; Khan, A. Latif

    1995-01-01

    high concentrations of the environmentally sensitive element selenium (average 13.4 ppm (parts per million)), compared to concentrations from United States coals of similar rank. The Makarwal coal bed represents a paleopeat that formed during changing relative ground-water base levels. Relatively low base levels were associated with periods of slow clastic deposition and lateritic paleosol development, followed by relatively high base levels that coincided with increased runoff, marine flooding, and clastic sedimentation that buried the paleopeat of the Makarwal. These environments formed along the northwestern margin of the Indian subcontinent as it drifted northward through equatorial latitudes in the Tethys Sea. The Makarwal coal bed is thin or absent in the northern part of the range where the Lumshiwal and Hangu Formations are the thinnest. Such rapid lateral changes (over about 25 km) in formation thickness and the apparent change in relative ground-water base level indicate that tectonically induced subsidence rates varied across the Surghar Range and influenced the deposition of the rocks that compose the two formations.

  16. Permanganate diffusion and reaction in sedimentary rocks.

    PubMed

    Huang, Qiuyuan; Dong, Hailiang; Towne, Rachael M; Fischer, Timothy B; Schaefer, Charles E

    2014-04-01

    In situ chemical oxidation using permanganate has frequently been used to treat chlorinated solvents in fractured bedrock aquifers. However, in systems where matrix back-diffusion is an important process, the ability of the oxidant to migrate and treat target contaminants within the rock matrix will likely determine the overall effectiveness of this remedial approach. In this study, a series of diffusion experiments were performed to measure the permanganate diffusion and reaction in four different types of sedimentary rocks (dark gray mudstone, light gray mudstone, red sandstone, and tan sandstone). Results showed that, within the experimental time frame (~2 months), oxidant migration into the rock was limited to distances less than 500 μm. The observed diffusivities for permanganate into the rock matrices ranged from 5.3 × 10(-13) to 1.3 × 10(-11) cm(2)/s. These values were reasonably predicted by accounting for both the rock oxidant demand and the effective diffusivity of the rock. Various Mn minerals formed as surface coatings from reduction of permanganate coupled with oxidation of total organic carbon (TOC), and the nature of the formed Mn minerals was dependent upon the rock type. Post-treatment tracer testing showed that these Mn mineral coatings had a negligible impact on diffusion through the rock. Overall, our results showed that the extent of permanganate diffusion and reaction depended on rock properties, including porosity, mineralogy, and organic carbon. These results have important implications for our understanding of long-term organic contaminant remediation in sedimentary rocks using permanganate.

  17. The physiology of rock climbing.

    PubMed

    Giles, Luisa V; Rhodes, Edward C; Taunton, Jack E

    2006-01-01

    In general, elite climbers have been characterised as small in stature, with low percentage body fat and body mass. Currently, there are mixed conclusions surrounding body mass and composition, potentially because of variable subject ability, method of assessment and calculation. Muscular strength and endurance in rock climbers have been primarily measured on the forearm, hand and fingers via dynamometry. When absolute hand strength was assessed, there was little difference between climbers and the general population. When expressed in relation to body mass, elite-level climbers scored significantly higher, highlighting the potential importance of low body mass. Rock climbing is characterised by repeated bouts of isometric contractions. Hand grip endurance has been measured by both repeated isometric contractions and sustained contractions, at a percentage of maximum voluntary contraction. Exercise times to fatigue during repeated isometric contractions have been found to be significantly better in climbers when compared with sedentary individuals. However, during sustained contractions until exhaustion, climbers did not differ from the normal population, emphasising the importance of the ability to perform repeated isometric forearm contractions without fatigue becoming detrimental to performance. A decrease in handgrip strength and endurance has been related to an increase in blood lactate, with lactate levels increasing with the angle of climbing. Active recovery has been shown to provide a better rate of recovery and allows the body to return to its pre-exercised state quicker. It could be suggested that an increased ability to tolerate and remove lactic acid during climbing may be beneficial. Because of increased demand placed upon the upper body during climbing of increased difficulty, possessing greater strength and endurance in the arms and shoulders could be advantageous. Flexibility has not been identified as a necessary determinant of climbing success

  18. Precambrian to Jurassic rocks of Arabian Gulf and adjacent areas: their facies, depositional setting, and hydrocarbon habitat

    SciTech Connect

    Alsharhan, A.S.; Kendal, C.G.S.C.

    1986-08-01

    The first sediments to onlap the metamorphosed Precambrian Arabian shield were Infracambrian (Proterozoic) to Middle Cambrian carbonates, clastics, and evaporites. The oldest Arabian reservoir rocks occur in the Precambrian to lower Paleozoic Era Salt of the Huqf Group, which forms the Birba field of Oman. The Middle Cambrian sequence was followed by Late Cambrian through Early Permian marine sandstones and continental to littoral siltstones and variegated shales. The first commercial oil discovered in the Arabian Gulf region occurs in fluvial sands of the Ordovician to Permian Haima and Haushi Groups of the Marmul field in south Oman. These strata are also productive in other fields and are sealed by unconformable contact with the Al Khlata Formation or beneath shale of the Albian Nahr Umr Formation. The deeply buried kerogen sediments of the Huqf Group to the southeast are believed to be the source rocks for these fields of south Oman. The Late Permian to Triassic deposits of the Arabian Peninsula are mainly widespread carbonates and evaporites that were deposited during a period of relative tectonic stability. Their deposition on an epeiric shelf was punctuated by a series of transgressions and regressions. Significant gas reserves have been proven in deep wells in the Arabian Gulf. These wells penetrate large deep structures in the Permian Khuff shelf carbonates. These carbonates have developed secondary porosity and lie beneath interbedded shale and dolomites of the Sudair or Suwei Formation. The source of gas in the Khuff is unknown but could lie in more deeply buried formations. The large deep structures of the Khuff are considered to be among the most attractive for gas potential in the region today. 14 figures, 2 tables.

  19. Turning Bread into Rocks: A Multisensory Unit Opener.

    ERIC Educational Resources Information Center

    Smith, Shaw

    2000-01-01

    Presents an earth science activity on rocks to demonstrate the vital links between minerals and rocks. Uses different kinds of breads to demonstrate that rocks, like breads, are composed of various ingredients in different proportions. (ASK)

  20. View of Highway 140 and Overhang Rock. Location of junction ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Highway 140 and Overhang Rock. Location of junction with Old Coulterville Road behind rock. Looking north-northwest - All Year Highway, Between Arch Rock & Yosemite Valley, El Portal, Mariposa County, CA