Science.gov

Sample records for kitakami massif northeast

  1. Eocene Paleolatitude of the Kitakami Massif in Northeastern Japan

    NASA Astrophysics Data System (ADS)

    Hoshi, H.; Hayakawa, K.

    2011-12-01

    The geologic basement of the Japan Arc consists primarily of rocks formed by subduction-related processes. Mesozoic to Cenozoic accretionary complexes are the vast majority of the subduction-related products, but there are also many fragments of ancient continents or volcanic islands or seamounts of different sizes, characterized by lithologies and geologic histories distinct from surrounding rocks. The South Kitakami Massif in northeastern Japan is typical of those allochthonous units. Early paleomagnetic studies demonstrated that the sedimentary rocks of the South Kitakami Massif have completely been remagnetized by intrusion of Cretaceous plutons. Recently, shallow paleomagnetic inclinations were reported from early Cretaceous and early Paleogene volcanic rocks of the Northern Kitakami Massif, leading to an interpretation that the whole Kitakami Massif was located at low latitude in the Cretaceous to early Paleogene. Here we present new paleomagnetic results from the Northern Kitakami Massif. Dacite dikes of Eocene age (ca. 44 Ma) and baked country rocks were sampled at 16 sites. The dikes possess vertical or subvertical intrusion surfaces, suggesting little or no significant tectonic tilt. We obtained for the first time an Eocene reliable paleomagnetic direction for the Kitakami massif; a positive baked contact test proves the primary nature of remanence. A suggestion that pre-Miocene rocks of northeastern Japan have completely been remagnetized can be eliminated. The mean direction is characterized by a westerly declination, indicating large counterclockwise rotation. Miocene rotational motion of the northeastern Japan Arc associated with backarc opening can account for this westerly direction. The mean inclination is statistically indistinguishable from that expected at the present latitude of the studied area, indicating little or no significant latitudinal motion. This finding provides a constraint on the suspected northward motion; the Kitakami Massif has not suffered latitudinal motion since at least Eocene time.

  2. A Late Permian coral reef complex, South Kitakami Terrane, Japan

    NASA Astrophysics Data System (ADS)

    Kawamura, Toshio; Machiyama, Hideaki

    1995-11-01

    The early Late Permian (Kubergandian to Midian) Iwaizaki Limestone of the South Kitakami Terrane, situated in Northeast Japan, represents a coral reef complex which was formed on a faulted-bank in an active continental margin. The reef-building organisms include cerioid and dendroid rugose corals, a fasciculate tabulate coral and solenoporacean algae as constructors, calcisponges, bryozoans and crinoids as bafflers, and Tubiphytes, Archaeolithoporella and cyanobacteria as binders. The biotic composition is more diverse than the other coeval reefs. Characterized by the existence of an obvious framework, this reef is similar to the Recent coral reefs and unique among Late Permian reefs, most of which are mainly formed by calcisponges and calcareous algae. The distribution of Late Permian reefs is closely related to the palaeoclimate. Coral reefs were developed mainly around the South China and Indochina continental masses between the Tethys Sea and the Panthalassa Ocean, in the tropics. While, calcisponge reefs and Tubiphytes-algal crust reefs were common in tropical to subtropical regions, and stromatolite-bryozoan reefs developed in arid areas. The gradational distribution of Late Permian organic reefs including localized development of coral reefs were probably caused by decreasing of the glaciers and changing of the ocean current systems.

  3. Magnetic and gravity constraints on forearc upper crustal structure and composition, offshore northeast Japan

    USGS Publications Warehouse

    Finn, C.

    1994-01-01

    Marine magnetic and gravity data from the northeast Japan forearc offer insight to the subsurface structure, density and magnetization from which geologic interpretations and tectonic reconstructions can be made. Positive marine magnetic anomalies, on-land geology, drill hole data, and 2-1/2-dimensional models reveal that Kitakami plutons and possibly their associated volcanic rocks constitute part of the modern forearc basement and lie 100-150 km further east than previously thought. A method to create magnetization and density contrast maps was employed to produce a three-dimensional picture of the forearc basement rock properties averaged over a 14-km thickness. -Author

  4. Craddock Massif and Vinson Massif remeasured

    USGS Publications Warehouse

    Gildea, Damien; Splettstoesser, John F.

    2007-01-01

    The highest peak in Antarctica, the Vinson Massif (78º35’S, 85º25’W), is at an elevation of 4892 m (16,046 ft), as determined in 2004. Measurements of the elevation have fluctuated over the years, from its earliest surveyed elevation of 5140 m (16,859 ft), to its present height. Vinson Massif and three of its near neighbors in the Sentinel Range of the Ellsworth Mountains are the highest peaks in Antarctica, making them a favorite objective of mountaineers. Well over 1,100 people have climbed Vinson since the first ascent by a team in the 1966-67 austral summer. The range is composed of Crashsite quartzite, making the Sentinel’s very resistant to erosion. Very accurate elevations have been achieved annually by GPS mapping done by a climbing team sponsored by the Omega Foundation, active in Antarctica since 1998. The Craddock Massif now includes Mt. Craddock, the ninth highest peak in Antarctica, at 4368 m (14,327 ft). Both are named for Campbell Craddock*, a U.S. geologist active in Antarctic research beginning in 1959-60.

  5. Kondyor Massif, Russia

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This is neither an impact crater nor a volcano. It is a perfect circular intrusion, about 10 km in diameter with a topographic ridge up to 600 m high. The Kondyor Massif is located in Eastern Siberia, Russia, north of the city of Khabarovsk. It is a rare form of igneous intrusion called alkaline-ultrabasic massif and it is full of rare minerals. The river flowing out of it forms placer mineral deposits. Last year 4 tons of platinum were mined there. A remarkable and very unusual mineralogical feature of the deposit is the presence of coarse crystals of Pt-Fe alloy, coated with gold. This 3-D perspective view was created by draping a simulated natural color ASTER composite over an ASTER-derived digital elevation model.

    The image was acquired on June 10, 2006, and is located at 57.6 degrees north latitude, 134.6 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  6. Ichthyofauna of the Kubo, Tochikura, and Ichinono river systems (Kitakami River drainage, northern Japan), with a comparison of predicted and surveyed species richness

    PubMed Central

    Nakae, Masanori; Senou, Hiroshi

    2014-01-01

    Abstract The potential fish species pool of the Kubo, Tochikura, and Ichinono river systems (tributaries of the Iwai River, Kitakami River drainage), Iwate Prefecture, northern Japan, was compared with the observed ichthyofauna by using historical records and new field surveys. Based on the literature survey, the potential species pool comprised 24 species/subspecies but only 20, including 7 non-native taxa, were recorded during the fieldwork. The absence during the survey of 11 species/subspecies from the potential species pool suggested either that sampling effort was insufficient, or that accurate determination of the potential species pool was hindered by lack of biogeographic data and ecological data related to the habitat use of the species. With respect to freshwater fish conservation in the area, Lethenteron reissneri, Carassius auratus buergeri, Pseudorasbora pumila, Tachysurus tokiensis, Oryzias latipes, and Cottus nozawae are regarded as priority species, and Cyprinus rubrofuscus, Pseudorasbora parva, and Micropterus salmoides as targets for removal. PMID:25425932

  7. The tectonics of anorthosite massifs

    NASA Technical Reports Server (NTRS)

    Seyfert, C. K.

    1981-01-01

    Anorthosite massifs developed approximately 1.4 to 1.5 billion years ago along an arch which developed parallel to a zone of continental separation as a block which included North America, Europe, and probably Asia separated from a block which included parts of South America, Africa, India, and Australia. Anorthosite massifs also developed at the same time along a belt which runs through the continents which comprise Gondwanaland (South America), Africa, India, Australia, and Antarctica. This was a zone of continental separation which subsequently became a zone of continental collision about 1.2 billion years ago. The northern anorthosite belt also parallels an orogenic belt which was active between 1.8 and 1.7 billion years ago. Heat generated during this mountain building period helped in the formation of the anorthosites.

  8. Evolution of stocks and massifs from burial of salt sheets, continental slope, northern Gulf of Mexico

    SciTech Connect

    Seni, S.J. )

    1991-03-01

    Salt structures in a 4000-km{sup 2} region of the continental slope, the northeast Green Canyon area, include stocks, massifs, remnant structures, and an allochthonous sheet. Salt-withdrawal basins include typical semicircular basins and an extensive linear trough that is largely salt-free. Counterregional growth faults truncate the landward margin of salt sheets that extend 30-50 km to the Sigsbee Escarpment. The withdrawal basins, stocks, and massifs occur within a large graben between an east-northeast-trending landward zone of shelf-margin growth faults and a parallel trend of counterregional growth faults located 48-64 km basinward. The graben formed by extension and subsidence as burial of the updip portion of a thick salt sheet produced massifs and stocks by downbuilding. Differential loading segmented the updip margin of the salt sheet into stocks and massifs separated by salt-withdrawal basins. Initially, low-relief structures evolved by trap-door growth as half-graben basins buried the salt sheet. Remnant-salt structures and a turtle-structure anticline overlay a salt-weld disconformity in sediments formerly separated by a salt sheet. Age of sediments below the weld is inferred to be be late Miocene to early Pliocene (4.6-5.3 Ma); age of sediments above the weld is late Pliocene (2.8-3.5 Ma). The missing interval of time (1-2.5 Ma) is the duration between emplacement of the salt sheet and burial of the sheet. Sheet extrusion began in the late Miocene to early Pliocene, and sheet burial began in the late Pliocene in the area of the submarine trough to early Pleistocene in the area of the massifs.

  9. Structural geology and sedimentology of the Sermat Quartzites, Strandja Massif, NW Turkey

    NASA Astrophysics Data System (ADS)

    Yazıcı, Müge; Natal'in, Boris A.

    2015-04-01

    The Strandja Massif, NW Turkey, is the eastern continuation of the Rhodope Massif in Bulgaria. The massif is generally correlated with the Hercynian orogenic belt that was later modified by the Cimmerian orogeny. The basement of the massif is composed by various kinds of gneisses and schists, which are intruded by the metagranites. In the studied area, the Cambrian K-feldspar metagranites are unconformably overlain by metaclastics, where both units have fault contacts with volcano-sedimentary rocks. The metagranite intrusions yield Carboniferous U-Pb zircon ages (Natal'in et al., 2012a). All of them constitute the basement of the Strandja Massif. Cambrian age of metagranites and their subduction related nature as well as the subduction related nature of the Carboniferous igneous rocks suggest a prolong evolution of the Strandja Massif (Natal'in et al., 2012a). The Cambrian metagranites are unconformably overlain by a metasedimetary cover unit, which is known in the literature as the Şermat Quartzite of presumably Permo-Triassic age (Çağlayan and Yurtsever, 1998). In the studied region, detrital zircons extracted from quartzites show that their depositional age is not younger than the Ordovician (Natal'in et al., 2012a). The basement of the Strandja Massif is subjected to the epidote-amphibolite-greenschist facies of metamorphism and high strain deformation in the late Jurassic - early Cretaceous times. The Şermat Quartzite forms a transgressive sequence, which starts with metaconglomerates, metasandstones and grades up to quartz-sericite schists. The thickness of bedding changes from thin to medium with parallel bedding planes, containing lens-shaped bodies of massive quartzites. The late Jurassic - early Cretaceous foliation (S1) is generally parallel to the primary bedding plane. Foliations and lineations consistently dip to the northeast and kinematic indicators suggest a tectonic transport in the same direction. High strain in the Şermat Quartzite prevented the preservation of sedimentary structures such as flute casts and cross-beddings, which can be used to determine the sedimentary environments of the Şermat Basin. Nevertheless, all available relicts indicate the transportation of sediments from a source area in the south. If the Şermat Quartzites is Ordovician age, they can be correlated with the Ordovician rocks of the Istanbul Zone, which is interpreted as a south-facing passive continental margin. Sedimentological framework of the Şermat Quartzites contradicts this correlation. Further studies of the region are necessary in order to determine the connection between the Strandja Massif and the Istanbul Zone. Keywords: Hercynian orogeny, Cimmerides, Strandja Massif, İstanbul Zone, Sedimentary Basin, Turkey References Çağlayan, M. A. & Yurtsever, A., 1998, Geological map of Turkey at 1:100000 scale, no. 20, 21, 22, 23, Burgaz-A3, Edirne-B2 and -B3, Burgaz A4, and Kırklareli-B4-B5-B6 and -C6 sheets, Mineral Research and Exploration Institute (MTA) of Turkey publications (in Turkish with English abstract). Natal'in, B., Sunal, G., Zhiqing, Y. & Gün, E., 2012a, Late Paleozoic subduction-accretion orogeny in the eastern part of the Turkish Strandja Massif (Vize - Kıyıköy region), in Kocbay, A., Esat, K., and Hasancebi, N., eds., 65th Geological Congress of Turkey. Abstracts Book: Ankara, Chamber of Geological Engineers, p. 454-455 Natal'in, B., Sunal, G., Satır, M. & Toraman, E., 2012, Tectonics of the Strandja Massif, NW Turkey: History of a Long-Lived Arc at the Northern Margin of Palaeo-Tethys: Turkish Journal of Earth Sciences, v. 21, p. 755-798.

  10. Structural style of cretaceous compression in the northern Bohemian massif of eastern Germany

    SciTech Connect

    Rigo, L.; Welker-Haddock, M. )

    1993-09-01

    The Bohemian massif was subjected to regional compressional stresses during Late Cretaceous Alpine, Dinaric, and Carpathian tectonic events. Older Mesozoic extensional and Variscan compressional fault planes were reactivated as decollement surfaces during this Late Cretaceous compression. Seismic profiles and geologic data suggest that Cretaceous faults are rooted in low-angle detachments and predominately compressional. In addition, an sinistral shear component is oriented oblique to the northwest-striking compressional component. The northern extremity of the Bohemian massif in eastern Germany is represented by the Thuringen, Harz, Flechtinger, and Calvoerde basement uplifts. The Thuringen block is bordered by a southwest-verging thrust fault, whereas the other three features are formed by a series of northeast-verging, northwest-striking, thrust faults. The Calvoerde structure is the northeasternmost basement-rooted feature in the Bohemian massif. As this structure approaches the Variscan Altmark paleohigh to the northwest, the fault decreases its throw and forms a lateral ramp. In the central European depression and Subhercynian basins, compressional stresses are transferred to decollement surfaces within Zechstein evaporites, creating halokenetic structures and reverse faults. The application of a compressional model creates additional hydrocarbon exploration opportunities in traditional reservoirs such as the Rotliegendes and Carboniferous in northern Germany. The model allows for the reinterpretation of some of the normal faults as oblique reverse shear faults. This holds particularly true for normal faults associated with Cretaceous halokenetic structures. The additional reverse and thrust faults will generate in inventory of previously untested footwall traps.

  11. Petrological and geochemical evolution of the Tolbachik volcanic massif, Kamchatka, Russia

    NASA Astrophysics Data System (ADS)

    Churikova, Tatiana G.; Gordeychik, Boris N.; Iwamori, Hikaru; Nakamura, Hitomi; Ishizuka, Osamu; Nishizawa, Tatsuji; Haraguchi, Satoru; Miyazaki, Takashi; Vaglarov, Bogdan S.

    2015-12-01

    Data on the geology, petrography, and geochemistry of Middle-Late-Pleistocene rocks from the Tolbachik volcanic massif (Kamchatka, Klyuchevskaya group of volcanoes) are presented and compared with rocks from the neighboring Mount Povorotnaya, Klyuchevskaya group basement, and Holocene-historical Tolbachik monogenetic cones. Two volcanic series of lavas, middle-K and high-K, are found in the Tolbachik massif. The results of our data analysis and computer modeling of crystallization at different P-T-H2O-fO2 conditions allow us to reconstruct the geochemical history of the massif. The Tolbachik volcanic massif started to form earlier than 86 ka based on K-Ar dating. During the formation of the pedestal and the lower parts of the stratovolcanoes, the middle-K melts, depleted relative to NMORB, fractionated in water-rich conditions (about 3% of H2O). At the Late Pleistocene-Holocene boundary, a large fissure zone was initiated and the geodynamical regime changed. Upwelling associated with intra-arc rifting generated melting from the same mantle source that produced magmas more enriched in incompatible trace elements and subduction components; these magmas are high-K, not depleted relative to N-MORB melts with island arc signatures and rift-like characteristics. The fissure opening caused degassing during magma ascent, and the high-K melts fractionated at anhydrous conditions. These high-K rocks contributed to the formation of the upper parts of stratovolcanoes. At the beginning of Holocene, the high-K rocks became prevalent and formed cinder cones and associated lava fields along the fissure zone. However, some features, including 1975-1976 Northern Breakthrough, are represented by middle-K high-Mg rocks, suggesting that both middle-K and high-K melts still exist in the Tolbachik system. Our results show that fractional crystallization at different water conditions and a variably depleted upper mantle source are responsible for all observed variations in rocks within the Tolbachik volcanic massif. Sr-Nd isotopes are consistent with 2-4% crustal assimilation during formation of the pedestal and stratovolcanoes, while the young lava fields do not show evidence of crustal assimilation. Major and trace element data coupled with K-Ar dating provide strong evidence that Mount Povorotnaya, located in 8 km northeast of Plosky Tolbachik, is an old block of the Tolbachik massif pedestal and for the moment it is the oldest (306 ka) known object in Klyuchevskaya group of volcanoes.

  12. The Lassell Massif - a Silicic Lunar Volcano

    NASA Astrophysics Data System (ADS)

    Ashley, J.; Robinson, M. S.; Stopar, J. D.; Glotch, T. D.; Hawke, B. R.; Lawrence, S. J.; Jolliff, B. L.; Greenhagen, B. T.; Paige, D. A.

    2013-12-01

    Lunar volcanic processes were dominated by mare-producing basaltic extrusions. However, limited occurrences of non-mare, geochemically evolved (Si-enriched) volcanic deposits have long been suspected on the basis of spectral anomalies (red spots), landform morphologies, and the occurrence of minor granitic components in Apollo sample suites [e.g., 1-5]. The LRO Diviner Lunar Radiometer Experiment (Diviner) measured thermal emission signatures considered diagnostic of highly silicic rocks in several red spot areas [6,7], within the Marius domes [8], and from the Compton-Belkovich feature on the lunar farside [9]. The present study focuses on the Lassell massif red spot (14.73°S, 350.97°E) located in northeastern Mare Nubium near the center of Alphonsus A crater. Here we use Diviner coverage co-projected with Lunar Reconnaissance Orbiter Camera (LROC) images [10] and digital elevation models to characterize the Lassell massif geomorphology and composition. Localized Diviner signatures indicating relatively high silica contents correlate with spatially distinct morphologic features across the Lassell massif. These features include sub-kilometer scale deposits with clear superposing relationships between units of different silica concentrations. The zone with the strongest signal corresponds to the southern half of the massif and the Lassell G and K depressions (formerly thought to be impact craters [11]). These steep-walled pits lack any obvious raised rims or ejecta blankets that would identify them as impact craters; they are likely explosive volcanic vents or collapse calderas. This silica-rich area is contained within the historic red spot area [4], but does not appear to fully overlap with it, implying compositionally distinct deposits originating from the same source region. Low-reflectance deposits, exposed by impact craters and mass wasting across the massif, suggest either basaltic pyroclastics or minor late-stage extrusion of basaltic lavas through vents within the structure. The Lassell massif is thus a volcanic construct with a range of silica concentrations. Based on landform morphology, some deposits appear enriched enough in silica to affect magma viscosity, the character of extrusion, and edifice construction. Stratigraphic relationships between the massif and surrounding deposits suggest that at least some volcanic activities associated with the massif occurred after mare emplacement. Together with volcanic features in the surrounding region, a compositionally and temporally complex volcanic history is supported for this portion of Mare Nubium. Magma production, extrusion, and timing of emplacement models would benefit from petrologic studies of new samples returned from this region. References: [1] Hagerty J. J. et al., (2006) JGR 111 (E06002). [2] Wagner R. et al., (2010) JGR 115 (E06015). [3] Wood C. A. and Head III J. W. (1975) Conf. on Origins of Mare Basalts, Lunar Sci. Inst., Houston, TX. [4] Whitaker E. A. (1972) Apollo 16 Prelim. Sci. Rpt. NASA SP-315, pp. 29-104 to 29-105. [5] Jolliff B. L. et al., (1991) Lunar Planet. Sci. Conf. XXI, 101-118. [6] Glotch T. D. et al., (2010) Science 329, 1510-1513. [7] Greenhagen B. T. et al., (2010) Science 329, 1507-1509. [8] Glotch T. D. et al., (2011) GRL, 38(L21204). [9] Jolliff B. L. et al., (2011) Nat Geosci. 4. [10] Robinson M. S. et al., (2010) Space Sci. Rev. 150(1-4), 81-124. [11] Wilhelms D. E. (1972) USGS Map I-722.

  13. Cambrian to Lower Ordovician complexes of the Kokchetav Massif and its fringing (Northern Kazakhstan): Structure, age, and tectonic settings

    NASA Astrophysics Data System (ADS)

    Degtyarev, K. E.; Tolmacheva, T. Yu.; Tretyakov, A. A.; Kotov, A. B.; Shatagin, K. N.

    2016-01-01

    A comprehensive study of the Lower Palaeozoic complexes of the Kokchetav Massif and its fringing has been carried out. It has allowed for the first time to discover and investigate in detail the stratified and intrusive complexes of the Cambrian-Early Ordovician. Fossil findings and isotope geochronology permitted the determination of their ages. The tectonic position and internal structures of those complexes have also been defined and their chemical features have been analyzed as well. The obtained data allowed us to put forward a model of the geodynamic evolution of Northern Kazakhstan in the Late Ediacaran-Earliest Ordovician. The accumulation of the oldest Ediacaran to Earliest Cambrian siliciclastics and carbonates confined to the Kokchetav Massif and its fringing occurred in a shallow shelf environment prior to its collision with the Neoproterozoic Daut island arc: complexes of the latter have been found in the northeast of the studied area. The Early Cambrian subduction of the Kokchetav Massif under the Daut island arc, their following collision and exhumation of HP complexes led to the formation of rugged ground topography, promoting deposition of siliceous-clastic and coarse clastic units during the Middle to early Late Cambrian. Those sediments were mainly sourced from eroded metamorphic complexes of the Kokchetav Massif basement. At the end of the Late Cambrian to the Early Ordovician within the boundaries of the massif with the Precambrian crust, volcanogenic and volcano-sedimentary units along with gabbros and granites with intraplate affinities were formed. Simultaneously in the surrounding zones, which represent relics of basins with oceanic crust, N-MORB- and E-MORB-type ophiolites were developed. These complexes originated under extensional settings occurred in the majority of the Caledonides of Kazakhstan and Northern Tian Shan. In the Early Floian Stage (Early Ordovician) older heterogeneous complexes were overlain by relatively monotonous siliceous-clastic units, that were being deposited until the Middle Darrivilian Stage (Middle Ordovician).

  14. Extensional ductile tectonics of the Sioule metamorphic series (Variscan French Massif Central)

    NASA Astrophysics Data System (ADS)

    Faure, M.; Grolier, J.; Pons, J.

    1993-09-01

    In the Northern part of the Variscan French Massif Central, the Sioule series, from top to bottom, consists of a pre-Visan granite, migmatite, gneiss and mica schist. Two ductile deformations have been recognized. The earlier phase is characterized by a north-east-south-west trending stretching lineation; the second phase, characterized by a north-west-south-east trending mineral, stretching and crenulation lineation, is better marked in the lower mica schist part than in the upper granito-gneissic part. This second phase occurred during retrogression of the metamorphic rocks; related shear criteria indicate a top to the south-west shear. The Namurian-Westphalian magmatic bodies such as the Echassires leucogranite, Pouzol-Servant microgranite and numerous north-east -south-west trending microgranite dykes are emplaced in extensional fractures related to the same north-west-south-east maximum stretching direction. The asymmetrical shapes of the two granitic massifs indicate that they intruded towards the south-east. The synkinematic retrogression of the metamorphic rocks, the shape of the magmatic bodies and a re-examination of the numerous available data support the interpretation that the deformation is due to the extensional tectonic regime related to the Variscan crustal re-quilibration. This interpretation is in agreement with the correlation of the Sioule series with the Chavanon series. The two series belong to a unique tectono-metamorphic unit left-laterally offset by the Stephanian motion of the Sillon Houiller fault. This study also shows that the Sillon Houiller did not play a significant part during the Namurian-Westphalian extensional tectonics of the Massif Central.

  15. Experimental and Modeling Studies of Massif Anorthosites

    NASA Technical Reports Server (NTRS)

    Longhi, John

    1999-01-01

    This termination report covers the latter part of a single research effort spanning several grant cycles. During this time there was a single title, "Experimental and Modeling Studies of Massif Anorthosites", but there were several contract numbers as the mode and location of NASA contract administration changed. Initially, the project was funded as an increment to the PI's other grant, "Early Differentiation of the Moon: Experimental and Modeling Studies", but subsequently it became an independent grant. Table 1 contains a brief summary of the dates and contract numbers.

  16. Water budget of the soils of sand massifs (with the Ust'-Kundryuchensk massif in rostov oblast as an example)

    NASA Astrophysics Data System (ADS)

    Kulik, K. N.; Kulik, N. F.; Kulik, A. K.

    2012-08-01

    Sand massifs in the steppe zone with coarse-textured sandy or loamy sandy soils are mainly characterized by the percolative type of the soil water regime. The annual precipitation penetrating into the groundwater through the aeration zone varies from 80% in the barren sands to 30% and lower in the overgrown sands. The study of the water budget of the Ust'-Kundryuchensk sand massif with an area of 15800 ha indicates that the total volume of the annual groundwater outflow from the massif reaches 10.5 million m3. The water discharged all year round from the sand massif into the Kundryuch'ya and Severskii Donets rivers is fresh and ultrafresh. It contributes to the water discharge of the rivers and desalinates the river water. This is an important nature-protection function of the sand massif.

  17. The western limits of the Seattle and Tacoma faults and their interaction with faults of the Olympic Massif, Washington (Invited)

    NASA Astrophysics Data System (ADS)

    Lamb, A.; Blakely, R. J.; Liberty, L. M.; Pratt, T. L.; Sherrod, B. L.

    2013-12-01

    Recently acquired high-resolution seismic-reflection and magnetic data show that the Seattle fault of Washington State extends 24-km west of its previously mapped extent and thus comprises a >100-km-long active fault zone. These same data reveal largely concealed faults and folds that kinematically link the Seattle fault with active faults in the Olympic Massif. Linkage between the Seattle fault and the north-northeast-striking Saddle Mountain fault in the Olympic Massif may explain the synchroneity of M7 earthquakes occurring on both these faults approximately 1,100 years ago. The western limits of the 20-km-long east-striking Tacoma fault, a backthrust in the hanging wall of the Seattle fault zone, forms the southern margin of the Seattle uplift in contact with the Tacoma basin to the south. A ~20-km-long potential-field lineament extends from the western limits of the Tacoma fault northward to the Seattle fault and may reflect a structure linking these active faults. A geologic model based on magnetic, gravity, and seismic data shows that this potential-field lineament is likely caused by a low-angle, west-verging thrust fault, that we refer to as the Dewatto fault. We suggest that the Dewatto fault was initiated during exhumation of the Olympic Massif but, because of changes in principal strain direction, today largely accommodates north-directed, strike-slip motion along the west margin of the Seattle uplift. Thus, the Dewatto and Saddle Mountain faults and the western parts of the Seattle and Tacoma faults kinematically interact to accommodate north-directed horizontal displacement of the Seattle uplift relative to the Olympic Massif.

  18. Two Types of Spatio-Temporal Distribution of Large Earthquakes during Holocene; A Case Study for Active Faults in Island Arc of Northeast Japan

    NASA Astrophysics Data System (ADS)

    Mizumoto, T.; Imaizumi, T.; Otsuki, K.; Kagohara, K.

    2006-12-01

    Northeast Japan is one of the most typical island arc-trench systems which is under EW-trending horizontal compression since ca. 3 Ma-DThe elastic thin layer of upper crust was buckled initially with wavelength of about 50 km, and eventually thrust faults were developed near the inflection line of these crustal folds. The hanging walls have been grown as mountainous regions, while Quaternary sedimentary basins have been formed on the footwalls. Mountain range along the Quaternary volcanic front (Ou Backbone Range) and the uplift zone in the back-arc region (Dewa Hill) are anticlinoriums associated with thrust planes dipping mountain-ward. Kitakami lowland between Kitakami Mountain Ranges (Non-volcanic outer arc) and Ou Backbone Range, Yokote, Yamagata, Nagai, and Yonezawa inter-mountain basins between Ou Backbone Range and Dewa Hill, and Shonai Plain on the west of Dewa Hill are synclinoliums, which have been subsided by the vertical load of hanging walls of thrust faults. There are two types for the relation for the pair of uplifting and subsiding region and thrust faults. One is the case where they are bounded by thrust faults on both sides, for an example, Ou Backbone Range between Kitakami lowland and Yokote inter-mountain basin. Other is the case where thrust faults are developed only on one side, for examples, west-dipping thrust fault zones between Ou Backbone range and Fukushima Basin- Sendai Plain, between Yamagata inter-mountain basin and Dewa Hill, and between Nagai-Yonezawa inter- mountain basins and Dewa Hill. We concentrated our study only on the Holocene events, because it is easier for us to obtain precise data on the timing of seismic events and the amount of vertical displacement per single event. We combined the data from field observations on fault scarplets on the Holocene terraces of different ages with the much data from the previous trench excavation surveys. As a result we found that all these active thrust faults show the recurrence intervals of 2,000 to 4,000 years, and seismic fault slips per single event of 1.5 to 2.0 m, at most 3.5 m. All data on seismic events were plotted on the time-space grids. The resolution of time limit is shorter than 1,000 years. This analysis revealed two types of time-space trends for seismic events. One is concerned with the case where uplift zones are bounded by thrust faults on both sides. We found in this case that large earthquakes with slip of about 2 m occurred alternatively on the two fault zones with time interval of 1,500 to 2,000 years. Other is concerned with the case where one-sided faults between mountainous zones and lowland zones are arranged linearly but discontinuously. Once anyone of the fault segments became active, they tend to have been active nearly simultaneously, probably due to seismic triggering.

  19. Spatial thermal radiometry contribution to the Massif armoricain and the Massif central (France) litho-structural study

    NASA Technical Reports Server (NTRS)

    Scanvic, J. Y. (principal investigator)

    1980-01-01

    The author has identified the following significant results. Although the limited number of images received did not permit construction of a thermal inertia map, important geological details were obtained in the areas of lithology and tectonics. Interpretation of day, night, and seasonal imagery resulted in differentiating broad calcareous and dolomitic units in the Causse Plateau. In the Massif amoricain, some granite massifs were delineated which were not observed by LANDSAT. Neotectonic faults were also revealed.

  20. NORTHEAST CLIMATE DATA

    EPA Science Inventory

    The Northeast Regional Climate Center (NRCC) database includes a complete collection of historical climate data for the northeastern United States as well as continually updated National Weather Service observations and forecasts. In addition, daily temperature and precipitation ...

  1. Northeast Elevation Mill #3, Northeast Elevation Mill #4 ...

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

    Northeast Elevation - Mill #3, Northeast Elevation - Mill #4 (with Section of Courtyard), Southeast Elevation - Mill #4 North - Boott Cotton Mills, John Street at Merrimack River, Lowell, Middlesex County, MA

  2. 7. View looking southeast, showing northeast approach and northeast sidewalk. ...

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

    7. View looking southeast, showing northeast approach and northeast sidewalk. - Water Street Bridge, Spanning Boston & Maine Railroad tracks at Water Street (U.S. Route 3), Concord, Merrimack County, NH

  3. VIEW OF NORTHEAST TOWARD MAINTENANCE SHED AT NORTHEAST CORNER OF ...

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

    VIEW OF NORTHEAST TOWARD MAINTENANCE SHED AT NORTHEAST CORNER OF PARK - Candler Park Historic District, Roughly bounded by Moreland, Dekalb, McLendon & Harold Avenues, Matthews Street & Clifton Terrace, Atlanta, Fulton County, GA

  4. 52. Ground floor, northeast corner, looking northeast at former delivery ...

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

    52. Ground floor, northeast corner, looking northeast at former delivery entries (archways have since been filled in) - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

  5. 5. INTERIOR OF NORTHEAST ROOM AND MEZZANINE, NORTHEAST VIEW OF ...

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

    5. INTERIOR OF NORTHEAST ROOM AND MEZZANINE, NORTHEAST VIEW OF (HOISTS IN CENTER). - Vanadium Corporation of America (VCA) Naturita Mill, Sampling Building & Ore Receiving Platform, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  6. Geological and geochemical reconnaissance in the central Santander Massif, Departments of Santander and Norte de Santander, Colombia

    USGS Publications Warehouse

    Evans, James George

    1976-01-01

    The central Santander Massif is composed of Precambrian Bucaramanga Gneiss and pre-Devonian Silgara Formation intruded by Mesozoic quartz diorite, quartz monzonite, and alaskite and Cretaceous or younger porphyry. Triassic (Bocas Formation), Jurassic (Jordan and Giron Formations).and Cretaceous (Tambor, Rosa Blanca, Paja, Tablazo, Simiti, La Luna, and Umir Formations) sedimentary rocks overlie the metamorphic rocks and are younger than most of the intrusions. A geological and geochemical reconnaissance of part of the central Santander Massif included the Vetas and California gold districts. At Vetas the gold is generally in brecciated aphanitic quartz and phyllonite. Dark-gray material in the ore may be graphite. The ore veins follow steep west-northwest- and north-northeast-striking fracture zones. No new gold deposits were found. Additional geochemical studies should concentrate on western Loma Pozo del Rey and on improvement of the gold extraction process. At California the gold is in pyritiferous quartz veins and quartz breccia. Ore containing black sooty material (graphite?) is highly radioactive. Some of the mineralization is post-Lower Cretaceous. Soil samples indicate that gold deposits lie under the thick blanket of soil on the ridges above the zone of mining. Three principal gold targets are outlined by gold and associated minerals in pan concentrates. The close relation of gold and copper anomalies suggests that copper may be useful as a pathfinder for gold elsewhere in the region. Based on occurrences of gold or high concentrations of pyrite or chalcopyrite in pan concentrates and on analytical data, eight potential gold targets are outlined in the central massif. Reconnaissance of the surrounding region is warranted.

  7. Rhyolites of the Mbpit Massif in the Cameroon Volcanic Line: an early extrusive volcanic episode of Eocene age

    NASA Astrophysics Data System (ADS)

    Wandji, Pierre; Tchokona Seuwui, Dieudonn; Bardintzeff, Jacques-Marie; Bellon, Herv; Platevoet, Bernard

    2008-11-01

    The Mbpit Massif, one of the oldest volcanoes of the Cameroon Volcanic Line, was built up during the Eocene (40K/40Ar ages of 45.5 and 44.0 Ma). Located in the Eastern part of the Noun Plain, North-East of Foumbot, this massif is made up mainly of rhyolitic domes and thick, viscous lava flows. Such felsic lavas are rather rare in the Cameroon Volcanic Line. Most rhyolites are porphyritic and contain phenocrysts of K-feldspars (Or97-89), Na-feldspars (Ab99-88) and quartz. Scarce Fe-Ti oxides comprise titanohaematite and hemo-ilmenite. Owing to their low CaO contents, rhyolite compositions range from metaluminous to peraluminous (with normative corundum) and less commonly, peralkaline (normative aegirine). Chondrite-normalised REE patterns show LREE enrichment; and LaN/YbN ratios between 12.2 and 17.2, with prominent negative Eu anomalies (0.16 < Eu/Eu* < 0.62). The Th/Ta ratios range between 2.6 and 3. Initial 87Sr/86Sr ratios (0.7047 and 0.7050) and 143Nd/144Nd ratios (0.5125 and 0.5126, ?Nd of -1.04 to +1.22) suggest mantle sources (HIMU (high with ? = 238U/204Pb), EM (Enriched Mantle), FOZO (FOcal ZOne) components) of the rhyolites accompanied by little or no crustal contamination.

  8. Northeast Hellas Landscape

    NASA Technical Reports Server (NTRS)

    2003-01-01

    MGS MOC Release No. MOC2-446, 8 August 2003

    This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image of pitted terrain northeast of Hellas Basin shows light-toned outcrops of layered, sedimentary rock, and a valley floor covered by large, dark ripples or small dunes. Similar light-toned sedimentary materials are found throughout the region immediately northeast of Hellas, and in the crater, Terby. The area shown is 3 km (1.9 mi) wide and located near 27.5oS, 281.7oW. Sunlight illuminates the scene from the upper left.

  9. (222)Rn activity concentration differences in groundwaters of three Variscan granitoid massifs in the Sudetes (NE Bohemian Massif, SW Poland).

    PubMed

    Przylibski, Tadeusz A; Gorecka, Joanna

    2014-08-01

    Based on research conducted in three Variscan granitoid massifs located within the crystalline Bohemian Massif, the authors confirmed that the higher the degree of their erosional dissection, the smaller the concentration of (222)Rn in groundwaters circulating in these massifs. This notion implies that radon waters and high-radon waters, from which at least some of the dissolved radon should be removed before feeding them as drinking water to the water-supply system, could be expected in granitoid massifs which have been poorly exposed by erosion. At the same time, such massifs must be taken into account as the areas of possible occurrence of radon medicinal waters, which in some countries can be used for balneotherapy in health resorts. Slightly eroded granitoid massifs should be also regarded as very probable radon prone areas or areas of high radon potential. PMID:24657989

  10. Massification in Higher Education: Large Classes and Student Learning

    ERIC Educational Resources Information Center

    Hornsby, David J.; Osman, Ruksana

    2014-01-01

    In introducing the special issue on "Large Class Pedagogy: Opportunities and Challenges of Massification" the present editorial takes stock of the emerging literature on this subject. We seek to contribute to the massificaiton debate by considering one result of it: large class teaching in higher education. Here we look to large classes

  11. Pre-School Education in the Massif Central (France).

    ERIC Educational Resources Information Center

    Serna, Emile

    This paper lists and tentatively assesses three experiments in preschool education in rural areas in France, and outlines the Massif Central development program which draws extensively on these experiments. In Experiment I, a peripatetic teacher worked with young children, concentrating on speech activities in four different single-class schools.

  12. Massification in Higher Education: Large Classes and Student Learning

    ERIC Educational Resources Information Center

    Hornsby, David J.; Osman, Ruksana

    2014-01-01

    In introducing the special issue on "Large Class Pedagogy: Opportunities and Challenges of Massification" the present editorial takes stock of the emerging literature on this subject. We seek to contribute to the massificaiton debate by considering one result of it: large class teaching in higher education. Here we look to large classes…

  13. Using several monitoring techniques to measure the rock mass deformation in the Montserrat Massif

    NASA Astrophysics Data System (ADS)

    Janeras, M.; Jara, J. A.; López, F.; Marturià, J.; Royán, M. J.; Vilaplana, J. M.; Aguasca, A.; Fàbregas, X.; Cabranes, F.; Gili, J. A.

    2015-09-01

    Montserrat Mountain is located near Barcelona in Catalonia, at the north-east corner of Spain, and its massif is formed by conglomerate interleaved by siltstone/sandstone with steep slopes very prone to rock falls. The increasing visitor's number in the monastery area, reaching 2.4 million per year, has pointed out the risk derived from rock falls for this building area and also for the terrestrial accesses, both roads and rack railway. A risk mitigation plan is currently been applied for 2014-2016 that contains monitoring testing and implementation as a key point. The preliminary results of the pilot tests carried out during 2014 are presented, also profiting from previous sparse experiences and data, and combining 4 monitoring techniques under different conditions of continuity in space and time domains, which are: displacement monitoring with Ground-based Synthetic Aperture Radar and characterization at slope scale, with an extremely non uniform atmospheric phase screen because of the stepped topography and atmosphere stratification; Terrestrial Laser Scanner surveys quantifying frequency for unnoticed activity of small rock falls, and monitoring rock block displacements over 1cm; monitoring of rock joints with a wireless net of sensors; and tentative surveying for singular rocky needles with Total Station.

  14. Northeast Regional Biomass Program

    SciTech Connect

    O'Connell, R.A.

    1991-11-01

    The management structure and program objectives for the Northeast Regional Biomass Program (NRBP) remain unchanged from previous years. Additional funding was provided by the Bonneville Power Administration Regional Biomass Program to continue the publication of articles in the Biologue. The Western Area Power Administration and the Council of Great Lakes Governors funded the project Characterization of Emissions from Burning Woodwaste''. A grant for the ninth year was received from DOE. The Northeast Regional Biomass Steering Committee selected the following four projects for funding for the next fiscal year. (1) Wood Waste Utilization Conference, (2) Performance Evaluation of Wood Systems in Commercial Facilities, (3) Wood Energy Market Utilization Training, (4) Update of the Facility Directory.

  15. Northeast Coast, Hokkaido, Japan

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The northeast coast of Hokkaido and Kunashir Island, Japan (44.0N, 143.0E) are seen bordered by drifting sea ice. The sea ice has formed a complex pattern of eddies in response to surface water currents and winds. Photos of this kind aid researchers in describing local ocean current patterns and the effects of wind speed and direction on the drift of surface material, such as ice floes or oil. Kunashir is the southernmost of the Kuril Islands.

  16. Northeast Regional Biomass Program

    SciTech Connect

    Lusk, P.D.

    1992-12-01

    The Northeast Regional Biomass Program has been in operation for a period of nine years. During this time, state managed programs and technical programs have been conducted covering a wide range of activities primarily aim at the use and applications of wood as a fuel. These activities include: assessments of available biomass resources; surveys to determine what industries, businesses, institutions, and utility companies use wood and wood waste for fuel; and workshops, seminars, and demonstrations to provide technical assistance. In the Northeast, an estimated 6.2 million tons of wood are used in the commercial and industrial sector, where 12.5 million cords are used for residential heating annually. Of this useage, 1504.7 mw of power has been generated from biomass. The use of wood energy products has had substantial employment and income benefits in the region. Although wood and woodwaste have received primary emphasis in the regional program, the use of municipal solid waste has received increased emphasis as an energy source. The energy contribution of biomass will increase as potentia users become more familiar with existing feedstocks, technologies, and applications. The Northeast Regional Biomass Program is designed to support region-specific to overcome near-term barriers to biomass energy use.

  17. New thermochronological constraints for the exhumation of the Aiguilles Rouges massif, Western Alps

    NASA Astrophysics Data System (ADS)

    Boutoux, Alexandre; Bellahsen, Nicolas; Pik, Raphael; Rolland, Yann; Verlaguet, Anne; Lacombe, Olivier

    2014-05-01

    During Oligo-Miocene times, the proximal part of the European passive margin underwent collisional shortening. In the outermost part of the Alpine arc, this shortening occurred in the fold-and-thrust belts (Bornes, Bauges, Chartreuse and Vercors massifs) with no significant tectonic burial. In the External Crystalline Massifs (ECM: Mont Blanc, Aiguilles Rouges, Belledonne, Oisans massifs) the crust was buried at mid-crustal depths below the internal units at 35 to 30 Ma. Along the ECORS profile, the timing of the Mont Blanc massif deformation and exhumation is now well constrained. However, the exhumation of the Aiguilles Rouges massif is much less constrained and this led to various and contrasting interpretations in terms of structural style and sequence of shortening. In this contribution, we present a new thermochronological dataset of the southern part of the Aiguilles Rouges massif. (U-Th-Sm)/He ages on zircons were obtained on three different elevation profiles. Preliminary results indicate ages around 7-8 Ma, which are consistent with Apatite Fission Track data. Those results will allow us to better constrain the timing of the Aiguilles Rouges massifs exhumation relative to the Mont Blanc massif and decipher whether these massifs are deformed in the forward sequence or not, if there were some out-of-sequence major shear zones/thrusts, or if these massifs were deformed sub-coevally. This has major implications in terms of both Alpine collisional wedge kinematics and crustal rheology of the European margin during the Tertiary collision.

  18. Fluid circulation systems in the Alpine External Crystalline Massifs

    NASA Astrophysics Data System (ADS)

    Boutoux, Alexandre; Bellahsen, Nicolas; Verlaguet, Anne; Lacombe, Olivier

    2014-05-01

    At mid-crustal levels, rock permeability is believed to be very low except in active fault/shear zones. In sedimentary rocks undergoing tectonic burial during collisional shortening, fluid flow is thus considered to be a small-scale process restricted to the sedimentary unit, until the fluid system locally opens during strain localization in fault/shear zones. During the Alpine collision, the European proximal passive margin (Dauphinois/Helvetic domains, including the External Crystalline Massifs, ECM: Aar, Mont Blanc, Aiguilles Rouges, Oisans massifs) was buried at mid-crustal depth under the internal units and was subsequently shortened and exhumed with contrasting kinematics. Indeed, some of the main tectonic units are sedimentary nappes detached from their basement while other are linked to main basement shear zones. In this context, many studies of fluid system evolution have been published, mainly focused on the largest tectonic units (e.g., Morcles nappe) and/or on thrust/shear zones with large displacement (e.g., Glarus thrust). In this contribution, we focused on tectonic structures located in the Oisans massif where small amount of shortening occurred (smaller than in the northern ECM, Mont Blanc and Aar). We performed geochemical and microthermometric analyses on calcite + quartz vein and host-rock samples to document and discuss the fluid source and pathway, the scale of circulation and the fluid-rock interactions. The fluid system in the Oisans ECM is compared to the fluid systems in other ECM and can be considered as an early and/or less shortened analogue. In the Oisans massif cover, the fluid system is generally closed, except locally above the main basement shear zones where signatures of basement-derived fluids were identified by trace element analysis. In contrast, in the Mont Blanc massif, fluids were channelized in the main basement shear zones, while in the Morcles nappe (i.e., the presumable cover of the Mont Blanc), deep fluids may have been channelized in the sheared reverse limb. Further north, in the Glarus thrust (i.e., the largest shear zone of the Aar massif), deep fluids were clearly channelized in the thrust zone. This highlights the influence on fluid systems of both the structural style and the amount of shortening that vary along the strike of the External Alps.

  19. The Apollo 17 samples: The Massifs and landslide

    NASA Technical Reports Server (NTRS)

    Ryder, Graham

    1992-01-01

    More than 50 kg of rock and regolith samples, a little less than half the total Apollo 17 sample mass, was collected from the highland stations at Taurus-Littrow. Twice as much material was collected from the North Massif as from the South Massif and its landslide (the apparent disproportionate collecting at the mare sites is mainly a reflection of the large size of a few individual basalt samples). Descriptions of the collection, documentation, and nature of the samples are given. A comprehensive catalog is currently being produced. Many of the samples have been intensely studied over the last 20 years and some of the rocks have become very familiar and depicted in popular works, particularly the dunite clast (72415), the troctolite sample (76535), and the station 6 boulder samples. Most of the boulder samples have been studied in Consortium mode, and many of the rake samples have received a basic petrological/geochemical characterization.

  20. K-alkaline rocks and lamproites of Tomtor massif

    NASA Astrophysics Data System (ADS)

    Vladykin, Nikolai

    2015-04-01

    Tomtor massif of the largest volcano-plutonic deep alkaline-carbonatite massifs world central type. Area of massif occupy 240 km2 and carbonatites stock is 40 km2. The super large deposit of Nb, TR, Y, Sc, Sr ,REE (Frolov et al. 2001)is found within the massif. The numerical publication are devoted to the ore mineralization there. But the geological struc-ture of the massif and the chemistry of its constituting rocks are not well understood. We obtained new ages based on U-Pb zircon and mica Ar-Ar method (Kotov, Vladykin et al. 2014 Vladykin et al. 2015). The massif was created in 2 stages: 700 and 400 Ma. We (Vla-dykin et al 1998) found rocks of lamproite series and proposed a new scheme of magmatism and the ore.genesis (Vladykin 2007, 2009). Biotite - pyroxenite, peridotite originated in first stage and then intruded iolites, nepheline and alkali syenite. Syenites occupy 70% of -massif and contain 12-13% K2O and 2-4% Na2O showing the K-alkaline-ultramafic nature of Tomtor volcano-plutonic massif (Vladykin 2009). The first stage was accomplished by nelsonitov calcite, dolomite and ankerite carbonatites. Second stage (400Ma) volcanics picrite - lamproite veins and eruptive breccias meli-lite, melanephelinites, tinguaites appered. These rocks are cut by carbonatites of second stage. It was finished by intensive explosive eruption of a silicate (lamproite) tuffs lavobrec-cia kimberlite formed Ebelyakhdiamondiferous placer, melilite rocks in diatremes (feeders), as well as carbonate-phosphate (kamaforite) explosive tuffs with siderite ores. This carbona-tite complex is preserved within the subsidence caldera. Tuff eruption in conjunction with gas and hydrothermal activity determined its rare metal mineralization. These rocks contain to: Nb- 21%, TR-15%, Y-1.5%, Sc-1%, Zr- 0,5% Zn-, Sr-6%, Ti-8%, Ba-4%, V - 8000 ppm, Be- 300 ppm, Ga- 80 ppm, Cr- 1200ppm, Ni- 230 ppm, Mo- 145 ppm, Pb- 4300 ppm, Th- 1500 ppm, U-193 ppm. Picrite - olivine (rare leucite) lamproite and formed volcanic flows, sills, dikes and breccia diatremes having total thickness up to 300 m. (Vladykin, Torbeeva 2005) Lamproites composed of faceted olivine crystals, elongated mica (20 to 50%) and pyroxenes and subor-dinate perovskite, chromite and magnetite. Lamproites are subjected to intense carbona-tion. Leucite lamproites are composed of rounded discharge leucite (substituted by car-bonate) graines, "plastered" by mica secretions and fine pyroxene grains and sometimes sanidines. Phlogopite - annite micas of phlogopite lamproite contains to TiO2 (4-8%) and Cr (up to 1000 ppm). Pyroxenes are diopsides and K prevail in sanidines. There are now Eu anomalies they reveal spectra similar to Australian Ol= lamproites. Isotopic studies (Pokrovsky 2001, Vladykin 2006) indicate mantle originof silicate rocks. and ores excluding secondary redeposition (Vladykin 2009). RFBR grant 15-05-01005.

  1. Miocene mass-transport sediments, Troodos Massif, Cyprus

    USGS Publications Warehouse

    Lord, A.R.; Harrison, R.W.; BouDagher-Fadel, M.; Stone, B.D.; Varol, O.

    2009-01-01

    Sediment mass-transport layers of submarine origin on the northern and southern flanks of the Troodos ophiolitic massif are dated biostratigraphically as early Miocene and late Miocene, respectively and therefore represent different seismogenic events in the uplift and erosional history of the Troodos terrane. Analysis of such events has potential for documenting Miocene seismic and uplift events regionally in the context of changing stress field directions and plate vectors through time. ?? 2009 The Geologists' Association.

  2. The French Atlantic littoral and the Massif Armoricain, part 3

    NASA Technical Reports Server (NTRS)

    Verger, F. (Principal Investigator); Scanvic, J. Y.; Monget, J. M.

    1977-01-01

    The author has identified the following significant results: (1) An original map of lineaments of the Armorican Massif and the Vendean platform was prepared. (2) Validity of spatial information through comparison with maps of various kinds, such as geological, geophysical, morphological, etc., was verified. (3) It was confirmed that LANDSAT images, in many cases, reflect data on deep phenomena which were only accessible geophysically and by means of borings. Tectonic domains were outlined, and known lineaments were extended.

  3. 30. NORTHEAST TO BLACKSMITH SHOP AREA IN NORTHEAST CORNER OF ...

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

    30. NORTHEAST TO BLACKSMITH SHOP AREA IN NORTHEAST CORNER OF FACTORY. A BENCH VICE STANDS IN LEFT FOREGROUND IN FRONT OF THE HOODED FORGE. MOUNTED ON THE WORK BENCH IS THE MAIN CASTING FROM AN ELI WINDMILL, USED AS A JIG TO SUPPORT PARTS DURING THE BABBITT BEARING POURING OPERATION. - Kregel Windmill Company Factory, 1416 Central Avenue, Nebraska City, Otoe County, NE

  4. 2. SOUTHWEST VIEW OF NORTH SIDE (NORTHEAST CORNER).. THE NORTHEAST ...

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

    2. SOUTHWEST VIEW OF NORTH SIDE (NORTHEAST CORNER).. THE NORTHEAST SIDE OF THE MINE OFFICE IS IN THE BACKGROUND. - Juniata Mill Complex, Mill Camp Shed, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  5. Complete Alpine reworking of the northern Menderes Massif, western Turkey

    NASA Astrophysics Data System (ADS)

    Cenki-Tok, B.; Expert, M.; Işık, V.; Candan, O.; Monié, P.; Bruguier, O.

    2015-11-01

    This study focuses on the petrology, geochronology and thermochronology of metamorphic rocks within the northern Menderes Massif in western Turkey. Metasediments belonging to the cover series of the Massif record pervasive amphibolite-facies metamorphism culminating at ca. 625-670 °C and 7-9 kbars. U-Th-Pb in situ ages on monazite and allanite from these metapelites record crustal thickening and nappe stacking associated with the internal imbrication of the Anatolide-Taurides platform during the Eocene. In addition, new 39Ar/40Ar single muscovite grain analyses on deformed rocks were performed in three localities within the northern Menderes Massif and ages range from 19.8 to 25.5 Ma. These mylonites may be related to both well-known detachments, Simav to the north and Alaşehir to the south, which accommodate Oligo-Miocene exhumation of the Menderes core complex. U-Th-Pb data on monazite grains (22.2 ± 0.2 Ma) from migmatites emplaced within the Simav detachment confirm these ages.

  6. Northeast Pacific flatfish management

    NASA Astrophysics Data System (ADS)

    Trumble, Robert J.

    1998-03-01

    Exploitation of northeast Pacific flatfish effectively began in the late 1800s with the fishery for Pacific halibut. Harvest of other flatfish occurred on a limited, local basis until foreign fishing fleets came to the area in the late 1950s. When US and Canadian fishermen replaced the foreign fleets in the 1970s and 1980s, a conservation-based management system designed to control foreign fishing was applied to the domestic fleet. Flatfish stock assessment is based on scientific surveys, both trawl and longline, and on catch-age models. In Alaskan waters since 1989 and since 1996 in Canadian waters, mandatory observers collect data on species composition, discards of flatfish and other groundfish, and catch and discards of prohibited species. Fishermen pay observer costs. Most biomass and harvest occurs in the Bering Sea-Aleutian Islands area. Many northeast Pacific flatfish are near record-high abundance, an order of magnitude higher than 20 years ago. Exploitation rates based on F35% or F0.1 generate acceptable biological catch of more than 1 million mt, but annual harvest reaches only 300,000 mt. Total groundfish harvest is limited by an optimum yield limit of 2 million mt in the Bering Sea-Aleutian Islands, where the acceptable biological catch is 3 million mt, and by limits on amounts of Pacific halibut and other prohibited species bycatch. Most flatfish are relatively low-value species, and fishermen chose to fish for more valuable species. A large, powerful fleet which developed under open access in the US saw fishing time decline and economic problems increase as catching capacity grew, while Canada stabilized its fleet with limited entry and catch restrictions for individual vessels.

  7. Alpine thermal events in the central Serbo-Macedonian Massif (southeastern Serbia)

    NASA Astrophysics Data System (ADS)

    Antić, Milorad D.; Kounov, Alexandre; Trivić, Branislav; Wetzel, Andreas; Peytcheva, Irena; von Quadt, Albrecht

    2015-11-01

    The Serbo-Macedonian Massif (SMM) represents a crystalline belt situated between the two diverging branches of the Eastern Mediterranean Alpine orogenic system, the northeast-vergent Carpatho-Balkanides and the southwest-vergent Dinarides and the Hellenides. We have applied fission-track analysis on apatites and zircons, coupled with structural field observations in order to reveal the low-temperature evolution of the SMM. Additionally, the age and geochemistry of the Palaeogene igneous rocks (i.e. Surdulica granodiorite and dacitic volcanic rocks) were determined by the LA-ICPMS U-Pb geochronology of zircons and geochemical analysis of main and trace elements in whole-rock samples. Three major cooling stages have been distinguished from the late Early Cretaceous to the Oligocene. The first stage represents rapid cooling through the partial annealing zones of zircon and apatite (300-60 °C) during the late Early to early Late Cretaceous (ca. 110-ca. 90 Ma). It is related to a post-orogenic extension following the regional nappe-stacking event in the Early Cretaceous. Middle to late Eocene (ca. 48-ca. 39 Ma) cooling is related to the formation of the Crnook-Osogovo-Lisets extensional dome and its exhumation along low-angle normal faults. The third event is related to regional cooling following the late Eocene magmatic pulse. During this pulse, the areas surrounding the Surdulica granodiorite (36 ± 1 Ma) and the slightly younger volcanic bodies (ca. 35 Ma) have reached temperatures higher than the apatite closure temperature (120 °C) but lower than ca. 250 °C. The geochemistry of the igneous samples reveals late- to post-orogenic tectonic setting during magma generation.

  8. Mohorovicic discontinuity depth analysis beneath North Patagonian Massif

    NASA Astrophysics Data System (ADS)

    Gmez Dacal, M. L.; Tocho, C.; Aragn, E.

    2013-05-01

    The North Patagonian Massif is a 100000 km2, sub-rectangular plateau that stands out 500 to 700 m higher in altitude than the surrounding topography. The creation of this plateau took place during the Oligocene through a sudden uplift without noticeable internal deformation. This quite different mechanical response between the massif and the surrounding back arc, the short time in which this process took place and a regional negative Bouguer anomaly in the massif area, raise the question about the isostatic compensation state of the previously mentioned massif. In the present work, a comparison between different results about the depth of the Mohorovicic discontinuity beneath the North Patagonian Massif and a later analysis is made. It has the objective to analyze the crustal thickness in the area to contribute in the determination of the isostatic balance and the better understanding of the Cenozoic evolution of the mentioned area. The comparison is made between four models; two of these were created with seismic information (Feng et al., 2006 and Bassin et al., 2000), another model with gravity information (Barzaghi et al., 2011) and the last one with a combination of both techniques (Tassara y Etchaurren, 2011). The latter was the result of the adaptation to the work area of a three-dimensional density model made with some additional information, mainly seismic, that constrain the surfaces. The work of restriction and adaptation of this model, the later analysis and comparison with the other three models and the combination of both seismic models to cover the lack of resolution in some areas, is presented here. According the different models, the crustal thickness of the study zone would be between 36 and 45 Km. and thicker than the surrounding areas. These results talk us about a crust thicker than normal and that could behave as a rigid and independent block. Moreover, it can be observed that there are noticeable differences between gravimetric and seismic models in the North Patagonian Massif area and in its West boundary but almost any difference in the other geographical limits. It is an interesting result and could be related with the isostatic compensation state of the area. References: Barzaghi R., Borghi A., Reguzzoni M., Sampietro D. Global Moho Estimate from GOCE Space-Wise Solution and a Local Application in the Mediterranean Area Bassin, C., Laske, G. and Masters, G., The Current Limits of Resolution for Surface Wave Tomography in North America, EOS Trans AGU, 81, F897, 2000. Feng M., Van der Lee S., Assumpao M.. Upper mantle structure of South America from joint inersion of waveforms and fundamental mode group velocities of Rayleigh waves. Journal of Goephysical Research, vol. 112, B04312, doi:10.1029/2006JB004449,2007 Tassara A., A. Echaurren, 2011. Anatomy of the Chilean Subduction Zone: Three-dimensional density model upgraded and compared against global-scale models. Geophysical journal international, doi: 10.1111/j.1365-246X.2012.05397.x

  9. Higher Education, Changing Labour Market and Social Mobility in the Era of Massification in China

    ERIC Educational Resources Information Center

    Mok, Ka Ho; Wu, Alfred M.

    2016-01-01

    This article attempts to investigate the relationship between the massification of higher education, labour market and social mobility in contemporary China. Though only a short period of time has elapsed from elite to mass education, China's higher education has been characterised as a wide, pervasive massification process. Similar to other East

  10. Massification without Equalisation: The Politics of Higher Education, Graduate Employment and Social Mobility in Hong Kong

    ERIC Educational Resources Information Center

    Lee, Siu-yau

    2016-01-01

    This article explains why the massification of higher education in Hong Kong has, contrary to the predictions of received wisdom, failed to enhance the upward social mobility of the youth in the city. Building upon recent literature in political science, it argues that massification can take different forms, which in turn determine the effects of

  11. Social Class Barriers of the Massification of Higher Education in Taiwan

    ERIC Educational Resources Information Center

    Ru-Jer, Wang

    2012-01-01

    In recent years, the rapid growth of higher education in Taiwan has led to an essential shift from education for the elite to the massification of higher education. Although this massification is making higher education more accessible, one of the main concerns is whether opportunities for higher education are the same among all social classes in

  12. Massification without Equalisation: The Politics of Higher Education, Graduate Employment and Social Mobility in Hong Kong

    ERIC Educational Resources Information Center

    Lee, Siu-yau

    2016-01-01

    This article explains why the massification of higher education in Hong Kong has, contrary to the predictions of received wisdom, failed to enhance the upward social mobility of the youth in the city. Building upon recent literature in political science, it argues that massification can take different forms, which in turn determine the effects of…

  13. Social Class Barriers of the Massification of Higher Education in Taiwan

    ERIC Educational Resources Information Center

    Ru-Jer, Wang

    2012-01-01

    In recent years, the rapid growth of higher education in Taiwan has led to an essential shift from education for the elite to the massification of higher education. Although this massification is making higher education more accessible, one of the main concerns is whether opportunities for higher education are the same among all social classes in…

  14. Petrogenetic characteristics of mafic-ultramafic massifs in Nizhne-Derbinsk complex (East Sayan Mountains)

    NASA Astrophysics Data System (ADS)

    Cherkasova, T.; Chernishov, A.; Goltsova, Yu; Timkin, T.; Abramova, R.

    2015-11-01

    The article describes the results of petrographic, petrochemical, petrofabric, mineralogical and geochemical studies of the major rock groups potentially Cu, Ni, Pt ore- bearing mafic-ultramafic massifs in the Nizhne- Derbinsk complex (Eastern Sayan Mountains). Based on the data interpretation the investigated massifs can be classified as peridotite- pyroxenite-gabbronorite formation of geosynclinal regime in Altai-Sayan folding area. Significant massif deformation occurred during the final post-consolidation formation stage. The petrographic features of gabbro and petrofabric patterns of the rock-forming minerals in the Burlakski and Nizhne-Derbinsk massifs indicated the fact that massifs were involved in the accretion-collisional development stage of the Central Asian folding belt during the final formation stages the Nizhne-Derbinsk complex.

  15. Labrador massif anorthosites: Chasing the liquids and their sources

    NASA Astrophysics Data System (ADS)

    Morse, S. A.

    2006-06-01

    Bulk analyses of plagioclase megacrysts in massif anorthosites contain enough information on the 11 major element oxides of common igneous rocks to retrieve their complete parent magma compositions. The necessary partition coefficients for this inversion process are generated from a core-drilled trapped liquid and a pure anorthosite autolith in the Anorthosite-Norite-Troctolite (ANT) Nain Plutonic Suite (NPS) of Labrador. When applied to plagioclase megacrysts from five anorthositic intrusions in the NPS, the CIPW norms of the derived liquids correctly classify the parent liquids of dark plagioclase as olivine-normative and those of pale plagioclase as quartz-normative. Dark plagioclase megacrysts have higher An, lower K and some tetrahedral ferrous iron, compared to pale megacrysts. Experimental melts considered parental to the Lower Zone troctolites of the Kiglapait Layered Intrusion plot closely among the calculated olivine-normative liquids from the Nain anorthosites, lending further credibility to the inversions. The coupled nature of silica activity and oxygen fugacity for these and other anorthosite magma types permits a classification of massif anorthosites from melatroctolite to andesine norite based on silication and redox state, with potential for quantitative treatment. This treatment may also scale with the degree of crustal contamination experienced by ponded anorthositic magmas. Experimentally determined linear partitioning of plagioclase confirms a narrowing of the binary loop with high pressure, and allows retrieval of one unknown among pressure, temperature and liquid composition. These principles can be used for modeling the plagioclase component of liquids at their source, their intermediate storage sites, during ascent and at emplacement conditions. Experiments on a model Kiglapait bulk composition at high pressure suggest the separation of magma at 11 kbar from a spinel harzburgite source, with crystallization of olivine on ascent to saturation with plagioclase. Ponding of such high-temperature liquids in the lower or middle crust allows assimilation and silication leading to the noritic trend. Felsic suspensions leaving mafic crystals behind can account for anorthosite intrusions at upper levels. Lithospheric extension permits uplift of mantle melting regions to shallower depths, not to be confused with crust, as inferred for the Central North American Rift. Crustal melting appears to be neither necessary nor viable as a source of ANT (perhaps excluding monzonite) magmas. Origins and ideas: The array of anorthosite massifs in eastern North America is of a length scale equal to the volcanic Cameroon Line, which also has a heterogeneous distribution of ages on a very much shorter time scale. Precursor anorthosites far older than the commonly recognized Mesoproterozoic massifs must reflect a deep and revisited root cause of the anorthosite epoch, which may have begun near the time of origin of the Earth's inner core. A tectonically related superplume origin of massif anorthosite magmatism is appealing and has some credibility in paleogeographic reconstructions of Laurentia. It can also explain the apparent Al-Fe-rich nature of the ANT mantle source. The Mg#-An trends of two vastly different layered mafic intrusions, Bushveld and Kiglapait, are uncannily parallel, suggesting a fundamental, scale-independent, physicochemical behavior of large magma systems.

  16. Petrogenesis of Variscan lamproites of the Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Krm?ek, Luk; Romer, Rolf L.; Glodny, Johannes

    2015-04-01

    Paleozoic convergence of Laurussia and Gondwana-derived terranes with subduction of oceanic and continental crust of various compositions metasomatized the local mantle, a process which eventually led to a highly heterogeneous lithospheric mantle beneath the European Variscides. The eastern termination of the European Variscides (Moldanubian and Saxo-Thuringian zones of the Bohemian Massif in the Czech Republic, Austria, Germany, and Poland) is unusual as within a small area, the mantle had been modified by material from several subduction zones. Along the eastern border of the Bohemian Massif, mantle-derived dyke intrusions of peralkaline, perpotassic, and ultrapotassic compositions occur. The rocks are distinguished by mineral associations with K-amphibole and Fe-microcline and correspond mineralogically to a new variety of silica-rich lamproites. Lamproites from the Moldanubian Zone contain characteristic Ba-Ti-Zr accessory minerals (e.g., baotite, benitoite, hollandite), whereas lamproites from the Saxo-Thuringian Zone lack these minerals. Variscan lamproites from the Bohemian Massif sampled lithospheric mantle, whose chemical signature reflects extreme depletion (low CaO and Al2O3 contents) followed by strong metasomatic enrichment by material released from the subducted rocks, giving rise to crust-like trace element pattern, variably radiogenic Sr and unradiogenic Nd isotopic compositions, crustal Pb isotopic compositions, and a wide range of ?7Li ratios ranging from markedly positive to highly negative values. The metasomatic component is variably prominent in the lamproites, depending on the extent of partial melting, and the nature of the source of the metasomatic component. Preferential melting of the metasomatically enriched lithospheric mantle with stable K-amphibole resulted in lamproitic melts with very negative ?7Li values, which correlate positively with the peralkalinity, HFSE contents, and lower ?Nd of these rocks. Both, higher degree of melting and consumption of the metasomatic component reduce the chemical and isotopic impact of the metasomatic contribution to the lamproites. The very positive ?7Li values of some lamproites together with the depleted geochemical signature of the whole rocks indicate that subducted altered oceanic crust also may have modified the source of these lamproites.

  17. Structural investigations in the Massif-Central, France

    NASA Technical Reports Server (NTRS)

    Scanvic, J. Y.

    1974-01-01

    This survey covered the French Massif-Central (where crystalline and volcanic rocks outcrop) and its surrounding sedimentaries, Bassin de Paris, Bassin d'Aquitaine and Rhodanian valley. One objective was the mapping of fracturing and the surveying of its relationship with known ore deposits. During this survey it was found that ERTS imagery outlines lithology in some sedimentary basins. On the other hand, in a basement area, under temperature climate conditions, lithology is rarely expressed. These observations can be related to the fact that band 5 gives excellent results above sedimentary basins in France and generally band 7 is the most useful in a basement area. Several examples show clearly the value of ERTS imagery for mapping linear features and circular structures. All the main fractures are identified with the exception of new ones found both in sedimentaries and basement areas. Other interesting findings concern sun elevation which, stereoscopic effect not being possible, simulates relief in a better way under certain conditions.

  18. Serpentinization and Life: Motivations for Drilling the Atlantis Massif

    NASA Astrophysics Data System (ADS)

    Frueh-Green, G. L.; Lang, S. Q.; Brazelton, W. J.; Schrenk, M. O.

    2014-12-01

    The Atlantis Massif, located at the intersection of the Atlantis transform fault and the Mid-Atlantic Ridge at 30°N, is one of the best-studied oceanic core complexes (OCCs) and is the target of IODP Expedition 357 late 2015. Drilling will address two exciting discoveries in ridge research: off-axis, serpentinite-hosted hydrothermal activity and carbonate precipitation, exemplified by the Lost City hydrothermal field, and the significance of tectono-magmatic processes in forming heterogeneous and variably serpentinized lithosphere as key components of slow spreading ridges. Serpentinization reactions at moderate- to low-temperatures result in alkaline fluids, characterized by elevated concentrations of abiotic hydrogen, methane and low molecular weight hydrocarbons, and which lead to precipitation of carbonate and brucite upon mixing with seawater. These highly reactive systems have major consequences for lithospheric cooling, global geochemical cycles, carbon sequestration and microbial activity. However, little is known about the nature and distribution of microbial communities in subsurface ultramafic environments and the potential for a hydrogen-based deep biosphere in areas of active serpentinization and fluid circulation. The continuous flux of reduced compounds provides abundant thermodynamic energy to drive chemolithoautotrophy, however, carbon availability may be limited in these high pH environments and represent a challenge for microbial growth. Here we review serpentinization processes as fundamental to understanding the evolution of oceanic lithosphere and discuss open questions related to the impact of serpentinization on the subsurface biosphere. Motivations for drilling the shallow subseafloor of the Atlantis Massif include: (1) exploring the extent and activity of the subsurface biosphere in young ultramafic and mafic seafloor; (2) quantifying the role of serpentinization in driving hydrothermal systems, in sustaining microbiological communities and in the sequestration of carbon in ultramafic rocks; (3) assessing how abiotic and biotic processes change with aging of the lithosphere and with variations in rock type; and (4) characterizing tectono-magmatic processes at OCCs and the evolution of hydrothermal activity associated with detachment faulting.

  19. Petrogenesis of massif anorthosites: a perspective from St. Urbain, Quebec

    SciTech Connect

    Gromet, L.P.; Dymek, R.F.

    1985-01-01

    The St. Urbain massif is a post-orogenic anorthosite pluton (approx. 500 km/sup 2/) emplaced within the central high-grade granulite terrain of the Grenville structural province. In contrast to other Grenville anorthosites, primary magmatic features are largely preserved. The massif consists predominantly of andesine anorthosite (AA) of remarkable purity containing abundant plagioclase megacrysts. AA has high K/sub 2/O (approx. 2 wgt.%), very high Sr contents (approx. 1200 ppm) and highly fractionated, low REE contents. Features of AA provide the following insights into anorthosite origins: (1) Crystallization from anorthositic magmas, as evidenced by early crystallization of abundant antiperthitic plag, and igneous emplacement of AA dikes and veins into older, unrelated labradorite anorthosite; (2) in situ crystallization of pyroxene after plag, with no direct evidence of earlier crystallization of mafic minerals from a basaltic parent magma; (3) limited differentiation during crystallization, indicated by small variation in plag and opx and limited variations in plag Sr and REE contents; (4) the involvement of water, suggested by the late igneous crystallization of biotite and the localized grain-boundary replacement of plag by calcic myrmekite (An/sub 80/ + qtz). (5) high temperature, relatively oxidizing conditions, indicated by magmatic hemoilmenite +/- rutile and rare ferropseudobrookite in AA and associated ores. AA crystallized from highly feldspathic, relatively oxidized, somewhat hydrous parent magma with little trapped melt. The development of a hyperfeldspathic parent magma with the requisite geochemical features can be ascribed to hydrous partial melting of mafic (to intermediate) rocks at deep crustal or greater depths, leaving a garnetiferous residue.

  20. Geodynamics map of northeast Asia

    USGS Publications Warehouse

    Parfenov, Leonid M., (compiler); Khanchuk, Alexander I.; Badarch, Gombosuren; Miller, Robert J.; Naumova, Vera V.; Nokleberg, Warren J.; Ogasawara, Masatsugu; Prokopiev, Andrei V.; Yan, Hongquan

    2013-01-01

    This map portrays the geodynamics of Northeast Asia at a scale of 1:5,000,000 using the concepts of plate tectonics and analysis of terranes and overlap assemblages. The map is the result of a detailed compilation and synthesis at 5 million scale and is part of a major international collaborative study of the mineral resources, metallogenesis, and tectonics of northeast Asia conducted from 1997 through 2002 by geologists from earth science agencies and universities in Russia, Mongolia, northeastern China, South Korea, Japan, and the USA.

  1. Basement tectonics of the southern termination of the Santander Massif, Eastern Cordillera, Colombian Andes

    SciTech Connect

    Kammer, A. )

    1993-02-01

    The Santander Massif is a broad, basement cored antiform which, where fully developed, is limited toward its eastern and western foreland basins by two oppositely dipping reverse faults, which involve minor thrusting within the foreland sediments. More internal faults, however, accommodated an east-west extension by limiting sedimentary wedges which have the structure of half-grabens. Both marginal and internal faults impart a near symmetrical fan structure to the massif. The alternating compressional and extensional deformation regimes are taken as evidence for a vertical flow model, in which laminar parts of the massif rose along slightly divergent movement paths, following the fan array of the faults, and triggered the extensional deformation at higher levels. Evidence for a steep attitude of the faults is provided by (1) normal faults which, when bordering secondary basement highs, become reverse faults of an opposed dip, and (2) by the Bucaramanga fault, which between the Santander Massif on its eastern side and the more southerly Mogotes-Arcabuco Massif on its western side inverts both dip and displacement. A further internal deformation, which controlled the massif's structural evolution, consists of a longitudinal stretch. This was mitigated within the basement itself by an internal arching, and, where transmitted to the foreland, was absorbed by minor transcurrent faults or by east-west trending normal faults, as is the case of the displaceD plateaus in the Bucaramanga area. Considering the deep-seated origin of the structures of the Santander Massif, it is suggested that the imbricate sheets of the Guaicaramo fold and thrust belt at the eastern foothills of the Cocuy Massif evolved out of steeply inclined synclines. Folding of these imbricate sheets reflects uplift of more foreland oriented basement blocks.

  2. Geology and Tectonic Evolution of the Kazda? Massif (NW Anatolia)

    NASA Astrophysics Data System (ADS)

    Erdo?an, B.; Akay, E.; Haszbek, A.; Sat?r, M.; Siebel, W.

    2009-04-01

    In the northwestern part of Anatolia along the Izmir-Ankara Suture Zone, the Kazda? and Uluda? metamorphic massifs form an E-W trending belt between the Sakarya Continent in the north and the Menderes Massif in the south. Internal succession of these two massifs have been described as metamorphic complexes consisting of various kinds of micaschists, quartz mica schist, gneisses, amphibolites and marbles. In the Kazda? metamorphics, metaophiolites have been described additionally (Okay et al., 1991; Yalt?rak and Okay, 1994; Okay et al., 1996; Duru et al., 2004). These metamorphic complexes were considered to form the basement of the Sakarya Continent tectonically overlain by the Early Permian (Topuz et al., 2004) to Late Triassic (Okay and Monie, 1997; Okay et al., 2002) Karakaya Complex. This old basement and the Karakaya Complex were suggested to be unconformably overlain by Liassic and younger platform limestones and detritals (Alt?ner et al., 1991). In the literature, it has also been suggested that the Kazda? Massif had experienced polyphase metamorphism, first during Carboniferous time, second during Early Triassic and third during Tertiary (Bingl, 1971; Okay et al., 1996; Okay and Sat?r, 2000). In this study we mapped the Kazda? Massif on 1/25000 scale, studied its internal stratigraphy and structures and performed some petrologic analyses and radiogenic age determinations. Stratigraphically in the lower part of the Kazda? metamorphic sequence, there is a part of an oceanic crust represented by metaultramafic rocks and gabbroic metacumulates. Geochemistry of these banded metagabbros show a mid-oceanic affinity. This oceanic crust is overlain, along an unconformity, by a platform type marble succession. At the base of the marbles, there is a basal conglomerate, clasts of which derived from the underlying ultramafic sequence. Thick white marble sequence is overlain along a gradational boundary with a metadetrital succession consisting of quartz mica schist and mica schists that are partly converted into migmatites. There are mafic metavolcanic intervals along the lower gradational zone and within various levels of the metadetrital unit and some marble lenses. The platform sequence resembles to the Mesozoic platform of the Sakarya continent and the underlying oceanic crust might be a part of a Paleotethys Ocean. The Kazda? succession had been subjected to high-grade migmatitic metamorphism accompanied by syntectonic granite emplacements. Zircons of these metagranites yielded U-Pb ages of 27.6 6.8 Ma and 207Pb/206 Pb evaporation ages of 30 Ma. The metadetrital sequences and migmatites show scattered 207Pb/206 Pb zircon evaporation ages ranging from 301.4 2.8 Ma, 274.9 3.1 Ma, 169.3 3.5 Ma indicating mixed ages with strong Alpine imprints. After metamorphism the Kazda? metamorphic sequence was internally imbricated by southward compression and the ultramafic sequence thrust on the top of the platform sequence. During this southward thrusting two different nappes emplaced successively on top of the Kazda? metamorphics from the north. The first nappe consists of a part of Karakaya Complex and the second one, at the top, consists of the etmi Melange. Our mapping results clearly show that all these nappe packages including the internally imbricated Kazda? metamorphics are cut by undeformed young granites of 18-24 Ma age (Okay and Sat?r, 2000). Exhumation of the Kazda? metamorphics was a result of the southerly imbrication which occurred after the emplacement of the syntectonic metagranites (29-30 Ma) and before the intrusion of the cross cutting young granites (~ 21 Ma) The present topographic relief of the mountain was the result of younger vertical movements dissipated among numerous E-W trending high angle normal faults observed on its southern slope facing to Edremit Bay. References Altiner , D., Koyi?it, A., Farinacci, A., Nicosia, U. and Conti, M.A. (1991) Jurassic-Lower Cretaceous stratigraphy and paleogeographic evolution of the southern part of the northwestern Anatolia. Geologica

  3. Lateral variation in lithospheric mantle beneath NE Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Puziewicz, Jacek; Matusiak-Ma?ek, Magdalena

    2010-05-01

    The samples of peridotites forming the subcontinental lithospheric mantle beneath SW Poland have been brought to the surface by alkaline Cenozoic volcanoes of the Central European Volcanic Province. The area of SW Poland belongs to the Variscan Bohemian Massif. The Cenozoic rifting event formed the Oh?e (Eger) Rift with voluminous volcanic sequences in the NW part of the Massif. Miocene lavas with abundant mantle xenoliths occur in SW Poland at the NE prolongation of the Oh?e Rift (e.g. Ksi?ginki nephelinite). The single ca. 4 - 4.5 My xenolith-bearing eruptions occur to the SE of the Rift (Kozkov and Lutynia basanites), which allows the comparison of lithospheric mantle located outside the rifted area to that located close to the rift, and to asses possible changes in the mantle during the time span of ca 20 My. The mantle peridotites from the Ksi?ginki nephelinite are affected by silicate-melt induced cryptic metasomatism resulting in enrichment of clinopyroxene in light REEs. All of them show similar equilibration temperatures in the range of 1000 - 1100 C. The pyroxenites of similar TE characteristics, some with well preserved cumulative textures, are common in the Ksi?ginki nephelinites. The composite xenoliths show that pyroxenites form the veins in peridotites. These data suggest that at least part of the lithospheric mantle beneath northern termination of Oh?e Rift was affected by silicate melt metasomatism and thermally rejuvenated, and its lithology was modified by addition of pyroxenitic veins. The modification was contemporaneous with volcanism. The peridotite xenoliths occurring in the 4 Ma Kozkov basanites (Czech Republic, ca 25 km SE from Oh?e Rift margin) yield temperatures of equilibration from 680 to 1065 C (Christensen et al. 2001). The 4.5 My basanites from Lutynia (SW Poland, ca 170 km ESE from the Oh?e Rift) contain peridotites which equlibrated at 960 to 1000 C. The clinopyroxenes occurring in these peridotites preserved three different kinds of REE patterns, all LREEs enriched and contain common post-garnet spinel-clinopyroxene symplectites (Matusiak-Ma?ek et al., submitted). These data suggest that the lithospheric mantle occurring outside the Oh?e Rift was also metasomatically modified. However, the record of older events is still preserved and the thermal rejuvenation does not occur in all places. The interpretation of lithospheric mantle structure and lithology based on xenoliths brought to the surface by alkaline lavas is subjected to uncertainties arising from accidental sampling, always representing only the parts of mantle penetrated by the lavas. However, the data presented above suggest that the lithospheric mantle occurring in the area of Oh?e Rift was strongly thermally rejuvenated and lithologically modified during Cenozoic, whereas outside the Rift the scale of rejuvenation and modification was smaller. REFERENCES Christensen, N. I., Medaris Jr., L. G., Wang, H. F. & Jelnek, E. (2001). Depth variation of seismic anisotropy and petrology in central European lithosphere: A tectonothermal synthesis from spinel lherzolite. Journal of Geophysical Research 106, B1, 645-664. Matusiak-Ma?ek, M., Puziewicz, J., Ntaflos, T., Grgoire, M., Downes, H. (submitted). Metasomatic effects in the lithospheric mantle beneath the NE Bohemian Massif: a case study of Lutynia (SW Poland) peridotite xenolith. Lithos.

  4. P-wave Receiver Functions reveal the Bohemian Massif crust

    NASA Astrophysics Data System (ADS)

    Kampfova Exnerova, Hana; Plomerova, Jaroslava; Vecsey, Ludek

    2015-04-01

    In this study we present initial results of P-wave Receiver Functions (RF) calculated from broad-band waveforms of teleseismic events recorded by temporary and permanent stations in the Bohemian Massif (BM, Central Europe). Temporary arrays BOHEMA I (2001-2003), BOHEMA II (2004-2005) and BOHEMA III (2005-2006) operated during passive seismic experiments oriented towards studying velocity structure of the lithosphere and the upper mantle. Receiver Functions show relative response of the Earth structure under a seismic station and nowadays represent frequently-used method to retrieve structure of the crust, whose knowledge is needed in various studies of the upper mantle. The recorded waveforms are composites of direct P and P-to-S converted waves that reverberate in the structure beneath the receiver (Ammon, 1997). The RFs are sensitive to seismic velocity contrast and are thus suited to identifying velocity discontinuities in the crust, including the Mohorovi?i? discontinuity (Moho). Relative travel-time delays of the converted phases detected in the RFs are transformed into estimates of discontinuity depths assuming external information on the vp/vs and P velocity. To evaluate RFs we use the Multiple-taper spectral correlation (MTC) method (Park and Levin, 2000) and process signals from teleseismic events at epicentral distances of 30 - 100 with magnitude Mw > 5.5. Recordings are filtered with Butterworth band-pass filter of 2 - 8 s. To select automatically signals which are strong enough, we calculate signal-to-noise ratios (SNR) in two steps. In the first step we calculate SNR for signals from intervals (-1s, 3s)/(-10s, -2s), where P-arrival time represent time zero. In the second step we broaden the intervals and calculate SNR for (-1s, 9s)/(-60s, -2s). We also employ forward modelling of the RFs using Interactive Receiver Functions Forward Modeller (IRFFM) (Tkal?i? et al., 2010) to produce, in the first step, one-dimensional velocity models under individual seismic station. Stacked traces of the RFs show strong conversions with positive polarity (indicating a velocity increase across the discontinuity) between 3.3 and 4.5 s after the P-wave arrival at almost all stations. We relate these pulses to conversions at the Moho discontinuity. Assuming a constant crustal vp/vs ratio (1.73) and average crustal velocity vp=6.3 km/s for all stations, analogically to Geissler et al (2012), we multiply the evaluated Ps delay times by factor of 8.3 km/s and estimate the Moho beneath the Bohemian Massif at depths between 27 and 37 km. The crust is thinnest in the western part of the BM, beneath the SW end of the Eger Rift. The Moldanubian part of the BM exhibits the thickest crust. At most of the stations we also see one or two intra-crustal conversions, sometimes stronger than that related to the Moho. Several stations exhibit significant variations of the RF with back-azimuth. The aim of this study is to update existing three dimensional P-velocity crustal model of the Bohemian Massif (Karousov et al., 2012) compiled from control-source seismic results.

  5. Low pressure granulites from the Bohemian Massif, Upper Austria

    NASA Astrophysics Data System (ADS)

    Sorger, Dominik; Daghighi, Donia; Simic, Katica; Pichler, Ruth; Schwaiger, Christian; Hauzenberger, Christoph; Linner, Manfred; Iglseder, Christoph

    2014-05-01

    Low pressure granulite facies rocks are commonly found in the Bohemian Massif in Upper Austria. They belong to the Moldanubian Unit and were metamorphosed during the last stage of the Variscan orogeny. The investigated granulites from the Donau valley (west of Linz), Lichtenberg (northwest of Linz), Sauwald (south of the river Danube) and Bad Leonfelden zone comprise mainly migmatic paragneisses. Most of these rocks underwent high degrees of melting forming meta- and diatexites (''Perlgneise)''. Al-rich metapelites with partly cm-sized garnet porphyroblasts, which are suitable for precise PT and PT-path determinations, can be found in some localities of this unit. In this study samples taken along the Danube valley between Linz and Wilhering, from Lichtenberg and from Bad Leonfelden (north of Linz) were sampled and investigated petrographically in detail. Since garnets are rare and usually consumed by cordierite, a sample with large garnets was investigated in detail. A chemical zoning profile across the c. 1cm large garnet displayed elevated Ca contents (Xgrs=0.06) in the central part which decreased discontinuously towards the rim to Xgrs=0.02. Almandine, pyrope and spessartine components do not show any pronounced zoning pattern. Most of the smaller garnet grains in other samples are also homogeneous in composition with a slight Xalm increase and Xprp decrease at the rims, typical for retrograde diffusional zoning. The cordierite-garnet-sillimanite-granulites as well as some mafic granulites were used for geothermobarometry. Metamorphic conditions of around 770C to 850C and 0.5-0.6 GPa could be obtained, which are similar to the values obtained by Tropper et al. (2006). P. Tropper I. Deibl F. Finger R. Kaindl (2006). P-T-t evolution of spinel-cordierite-garnet gneisses from the Sauwald Zone (Southern Bohemian Massif, Upper Austria): is there evidence for two independent late-Variscan low-P / high-T events in the Moldanubian Unit? Int J Earth Sci (Geol Rundsch) (2006) 95: 1019-1037.

  6. Seismic Anisotropy of The Upper Mantle Beneath The Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Vecsey, L.; Plomerovaa, J.; Babuska, V.; Granet, M.

    The study of deep structure of the lithosphere of the Bohemian Massif (BM) by means of seismic anisotropy is based on teleseismic body wave observations and on a joint inversion of anisotropic data (P-residual spheres, the fast shear-wave polarisations and split times). We observe that velocity anomalies are strongly affected by different ori- entations of dipping anisotropic structures within the mantle lithosphere. There are distinct lateral variations of the pattern of P-residual spheres as well as of the split time dt and orientation of the fast shear waves. While in the central part of the BM a large dt and a general E-W orientation of the fast split wave prevail, in the eastern part the dt is smaller and the fast polarisation rotates to the WNW-ESE direction. The mantle lithosphere of the BM appears to consist of at least three domains with dif- ferent orientation of the large-scale fabric. The domains, which we interpret by 3D self-consistent anisotropic models, are separated by sutures cutting the whole litho- sphere. In our research we put special emphasis on the western part of the BM. The region is characterised by the well known earthquake swarms concentrated mainly within the brittle part of the upper crust above the crossing of the deep suture be- tween the Saxothuringian (S) and the Moldanubian (M) with the tectonically active Marianske Lazne (ML) fault. In the mantle lithosphere of both units we observe di- vergently oriented anisotropic structures with typical shear-wave splittings around 1 s or more. Near the deep suture beneath the centre of the swarm near Novy Kostel we observe decreased anisotropy which can be caused by a weakened fabric of the mantle lithosphere. An international seismic field experiment BOHEMA (BOhemian Massif HEterogeneity and Anisotropy) has been running in the region since October 2001. It aims at studying the structure and processes in the crust and upper mantle by means of integrated seismic tomography.

  7. Cooling Rates in the Atlantis Massif Oceanic Core Complex

    NASA Astrophysics Data System (ADS)

    McCaig, A. M.; Dixit, A.; Titarenko, S.

    2013-12-01

    We report Ca-in-olivine geospeedometry on 7 samples from IODP Hole 1309D, drilled into the Atlantis Massif oceanic core complex at 30N just west of the mid-Atlantic Ridge. Cooling rates were first calculated using the method of Coogan et al., (2002; 2007) on a total of 20 olivine grains in olivine gabbros and troctolitic gabbros. Apparent rates ranged from 2000 to 72,000 C/my, with the fastest rates from two samples at about 1000 mbsf, and slower rates from five samples between 294 and 499 mbsf. At shallower depths olivine is almost entirely absent due to alteration. The data was then reprocessed using the recent Fe-dependent calibration of Ca partitioning between olivine and two-pyroxene assemblages (Shejwalkar and Coogan, Lithos, in press). Olivine compositions range from Fo87 to Fo80 in the upper set of samples and Fo69-71 in the two deeper samples. Calculated cooling rates are reduced in all samples except the most Fo-rich, and by a factor of 15 in the most Fe-rich olivines. The result is a much smaller spread in mean cooling rates to 960-5610 C/my, without any clear depth-dependence. These rates are consistent with published average rates from isotopic closure temperatures, and are comparable to published data from ODP Hole 735b in a similar setting on the southwest Indian Ridge (Coogan et al., 2007), although inclusion of Fe-dependence will probably reduce those rates considerably. Gabbros in the Atlantis Massif have been exhumed by slip on an oceanic detachment fault, but without the extensive high temperature mylonitization seen in ODP Hole 735b. We present models (using Comsol Multiphysics) of the thermal evolution of oceanic core complexes incorporating footwall exhumation and hydrothermal circulation, which appears to have focussed within the detachment fault zone in Hole 1309D. Cooling rates are faster than predicted by purely conductive models but slower than models in which active hydrothermal circulation extends to the depth of gabbro emplacement.

  8. The Subduction of Continental Crust, the Variscan Evolution of the Bohemian Massif, and the Origin of PO Granitoids

    NASA Astrophysics Data System (ADS)

    Brueckner, H. K.

    2012-04-01

    Slices of continental crust subducted into the mantle during collisional orogeny may either undergo metamorphism and exhumation towards the surface as coherent slab-like or domal high pressure/ultrahigh pressure (HP/UHP) terranes or, if stalled or delayed in the mantle, melt and return towards the surface as magmas, or undergo a combination of exhumation and melting. Some exhumed HP/UHP terranes contain synorogenic granitoid bodies demonstrating melting does occur during exhumation. Therefore, crust that remains trapped in the mantle will also melt when temperatures reach the appropriate solidi through adiabatic decompression and/or conductive heating and/or radioactive decay. Subducted terranes with hydrous phases will undergo hydrate-breakdown melting and could melt during subduction, when stalled in the mantle or during exhumation. Terranes lacking hydrous phases probably require melting by adiabatic decompression as heated crust becomes ductile and rises as diapirs through the mantle wedge. The generated magmas will intrude through the overlying mantle wedge and into the overlying continental crust to form late orogenic and post orogenic (PO) granitoids depending on the time required to reach solidus temperatures. Geochemical characteristics will depend on P-T conditions, the age/chemistry/mineralogy of the subducted terrane (especially the presence or lack of hydrous phases), and the degree of melt interaction (i.e. the traverse length) with the mantle wedge. Melts that significantly traverse the wedge will acquire the hybrid mantle/crust nature of many PO granitoids. Melts generated by adiabatic decompression close to or within the continental crust will retain ancient crustal signatures. The Variscan evolution of the Bohemian Massif involved two episodes of subduction of continental crust: (1), the southward (present coordinates) subduction of Saxo-Thuringia beneath Bohemia (aka Tapla-Barrandia) along an east-west suture at 400-370 Ma followed by, (2), the east-northeast subduction of Moldanubia beneath Bohemia at 340-320 Ma1. The first subduction was followed by the intrusion of granitoids, including the Central Bohemian Batholith, between 370-340 Ma, all occurring south of the Saxo-Thuringian - Bohemia suture suggesting elements of the subducted Saxo-Thuringian continental crust melted and intruded the overlying Bohemian Craton. The second subduction event was accompanied and followed by multiple intrusions of granites (340 Ma synorogenic granitoids, 340-310 Ma post-orogenic S and high-K granitoids, and 310-290 I-type granitoids2) all occurring west of the of the Moldanubia-Bohemia suture suggesting elements of the subducted Moldanubian crust were melted and intruded the overlying Bohemian/Saxo-Thuringian Craton. Many of the HP/UHP terranes in the Bohemian Massif occur in domal structures suggesting exhumation and melting occurred in part by diapiric upwelling3. It is proposed that both the Saxo-Thuringian and Moldanubian terranes were exhumed by a combination of slab-return and diapiric upwelling and that elements of both terranes were stranded long enough in the mantle to heat up and melt to form most or all of the PO granitoids of the Bohemian Massif. This model involves successive re-distillation of the continental crust and may play a significant role in the evolution of both the continental crust and upper mantle. 1Medaris et al., 2005, Lithos 82. 2Finger et al., 1997, Min & Pet 61. 3Stpsk et a., 04, J. Met. Geol. 22.

  9. Northeast Regional Biomass Energy Program

    SciTech Connect

    O'Connell, R.A.

    1992-04-01

    The Northeast Regional Biomass Program (NRBP) is entering its ninth year of operation. The management and the objectives have virtually remained unchanged and are stated as follows. The program conducted by NRBP has three basic features: (1) a state grant component that provides funds (with a 50 percent matching requirement) to each of the states in the region to strengthen and integrate the work of state agencies involved in biomass energy; (2) a series of technical reports and studies in areas that have been identified as being of critical importance to the development of biomass energy in the region; and (3) a continuous long range planning component with heavy private sector involvement that helps to identify activities necessary to spur greater development and use of biomass energy in the Northeast.

  10. Northeast Regional Biomass Energy Program

    SciTech Connect

    O'Connell, R.A.

    1992-02-01

    The Northeast Regional Biomass Program (NRBP) is entering its ninth year of operation. The management and the objectives have virtually remained unchanged and are stated as follows. The program conducted by NRBP has three basic features: (1) a state grant component that provides funds (with a 50 percent matching requirement) to each of the states in the region to strengthen and integrate the work of state agencies involved in biomass energy; (2) a series of technical reports and studies in areas that have been identified as being of critical importance to the development of biomass energy in the region; and (3) a continuous long range planning component with heavy private sector involvement that helps to identify activities necessary to spur greater development and use of biomass energy in the Northeast.

  11. The Northeast Climate Science Center

    NASA Astrophysics Data System (ADS)

    Ratnaswamy, M. J.; Palmer, R. N.; Morelli, T.; Staudinger, M.; Holland, A. R.

    2013-12-01

    The Department of Interior Northeast Climate Science Center (NE CSC) is part of a federal network of eight Climate Science Centers created to provide scientific information, tools, and techniques that managers and other parties interested in land, water, wildlife and cultural resources can use to anticipate, monitor, and adapt to climate change. Recognizing the critical threats, unique climate challenges, and expansive and diverse nature of the northeast region, the University of Massachusetts Amherst, College of Menominee Nation, Columbia University, Marine Biological Laboratory, University of Minnesota, University of Missouri Columbia, and University of Wisconsin-Madison have formed a consortium to host the NE CSC. This partnership with the U.S. Geological Survey climate science center network provides wide-reaching expertise, resources, and established professional collaborations in both climate science and natural and cultural resources management. This interdisciplinary approach is needed for successfully meeting the regional needs for climate impact assessment, adaptive management, education, and stakeholder outreach throughout the northeast region. Thus, the NE CSC conducts research, both through its general funds and its annual competitive award process, that responds to the needs of natural resource management partners that exist, in part or whole, within the NE CSC bounds. This domain includes the North Atlantic, Upper Midwest and Great Lakes, Eastern Tallgrass and Big Rivers, and Appalachian Landscape Conservation Cooperatives (LCCs), among other management stakeholders. For example, researchers are developing techniques to monitor tree range dynamics as affected by natural disturbances which can enable adaptation of projected climate impacts; conducting a Designing Sustainable Landscapes project to assess the capability of current and potential future landscapes in the Northeast to provide integral ecosystems and suitable habitat for a suite of representative species and provide guidance for strategic habitat conservation; studying the effects of changes in the frequency and magnitude of drought and stream temperature on brook trout habitats, spatial distribution and population persistence; and conducting assessments of northeastern regional climate projections and high-resolution downscaling.

  12. Paleoproterozoic anorogenic granitoids of the Zheltav sialic massif (Southern Kazakhstan): Structural position and geochronology

    NASA Astrophysics Data System (ADS)

    Tretyakov, A. A.; Degtyarev, K. E.; Sal'nikova, E. B.; Shatagin, K. N.; Kotov, A. B.; Ryazantsev, A. V.; Pilitsyna, A. V.; Yakovleva, S. Z.; Tolmacheva, E. V.; Plotkina, Yu. V.

    2016-01-01

    The basement of the Zheltav sialic massif (Southern Kazakhstan) is composed of different metamorphic rocks united into the Anrakhai Complex. In the southeastern part of the massif, these rocks form a large antiform with the core represented by amphibole and clinopyroxene gneissic granite varieties. By their chemical composition, dominant amphibole (hastingsite) gneissic granites correspond to subalkaline granites, while their petroand geochemical properties make them close to A-type granites. The U-Pb geochronological study of accessory zircons yielded an age of 1841 ± 6 Ma, which corresponds to the crystallization age of melts parental for protoliths of amphibole gneissic granites of the Zheltav Massif. Thus, the structural-geological and geochronological data make it possible to define the Paleoproterozoic (Staterian) stage of anorogenic magmatism in the Precambrian history of the Zheltav Massif. The combined Sm-Nd isotopic—geochronological data and age estimates obtained for detrital zircons indicate the significant role of the Paleoproterozoic tectono-magmatic stage in the formation of the Precambrian continental crust of sialic massifs in Kazakhstan and northern Tien Shan.

  13. Occurrence of springs in massifs of crystalline rocks, northern Portugal

    NASA Astrophysics Data System (ADS)

    Pacheco, Fernando Antnio Leal; Alencoo, Ana Maria Pires

    2002-02-01

    An inventory of artesian springs emerging from fractures (fracture springs) was conducted in the Pinho River Basin and Morais Massif, northern Portugal, comprising an area of approximately 650 km2. Over 1,500 springs were identified and associated with geological domains and fracture sets. Using cross-tabulation analysis, spring distributions by fracture sets were compared among geological environments, and the deviations related to differences in rock structure and, presumably, to differences in deformational histories. The relation between spring frequencies and rock structures was further investigated by spectral determination, the model introduced in this study. Input data are the spring frequencies and fracture lengths in each geological domain, in addition to the angles between fracture strikes and present-day stress-field orientation (?). The model's output includes the so-called intrinsic densities, a parameter indexing spring occurrence to factors such as fracture type and associated deformational regime and age. The highest densities (12.2 springs/km of lineament) were associated with young shear fractures produced by brittle deformation, and the lowest (0.1) with old tensional and ductile fractures. Spectral determination also relates each orientation class to a dominant structural parameter: where spring occurrence is controlled by ?, the class is parallel to the present-day stress-field orientation; where the control is attributed to the length of fractures, the spring occurrence follows the strike of large-scale normal faults crossing the region. Rsum. Un inventaire des sources artsiennes mergeant de fractures (sources de fractures) a t ralis dans le bassin de la rivire Pinho et dans le massif de Morais, dans le nord du Portugal, dans une rgion couvrant environ 650 km2. Plus de 1,500 sources ont t identifies et associes des domaines gologiques et des ensembles de fractures. Grce une analyse de tableaux croiss, les distributions des sources par ensemble de fractures ont t compares aux situations gologiques et aux carts lis aux diffrences dans les structures des roches et, probablement, aux diffrences dans leurs histoires de dformations. Les relations entre la frquence des sources et la structure des roches ont t tudies ensuite par dtermination spectrale, modle prsent dans cette tude. Les donnes d'entre sont les frquences des sources et les longueurs des fractures dans chaque domaine gologique, en plus des angles entre directions de fractures et orientation du champ de contraintes actuel (?). La sortie du modle donne les densits dites intrinsques, un paramtre indexant l'existence d'une source des facteurs tels que le type de fracture et le rgime et l'ge associs de la dformation. Les densits les plus fortes (12,2 sources par km de linament) ont t associes des fractures jeunes produites par des dformations lentes, et les plus faibles (0,1) aux fractures anciennes ductiles et de tension. La dtermination spectrale associe galement chaque classe d'orientation un paramtre structural dominant: quand la prsence d'une source est contrle par ?, la classe est parallle l'orientation actuelle du champ de contrainte; lorsque le contrle est attribu la longueur des fractures, la prsence de sources suit le plan des failles normales grande chelle traversant la rgion. Resumen. Se ha llevado a cabo un inventario de manantiales emergentes de fracturas (manantiales de fracturas) en la cuenca del Ro Pinho y en el Macizo de Morais. El rea estudiada ocupa unos 650 km2 y se halla al Norte de Portugal. Se ha identificado ms de 1.500 manantiales, los cuales han sido asociados con dominios geolgicos y conjuntos de fracturas. Mediante el Anlisis de la Tabulacin Cruzada, se ha comparado la distribucin de los manantiales por conjuntos de fracturas entre ambientes geolgicos, as como las desviaciones relacionadas con diferencias en la estructura de la roca y,

  14. Volcanoes of the Tibesti massif (Chad, northern Africa)

    NASA Astrophysics Data System (ADS)

    Permenter, Jason L.; Oppenheimer, Clive

    2007-04-01

    The Tibesti massif, one of the most prominent features of the Sahara desert, covers an area of some 100,000 km2. Though largely absent from scientific inquiry for several decades, it is one of the worlds major volcanic provinces, and a key example of continental hot spot volcanism. The intense activity of the TVP began as early as the Oligocene, though the major products that mark its surface date from Lower Miocene to Quaternary (Furon (Geology of Africa. Oliver & Boyd, Edinburgh (trans 1963, orig French 1960), pp 1-377, 1963)); Gourgaud and Vincent (J Volcanol Geotherm Res 129:261-290, 2004). We present here a new and consistent analysis of each of the main components of the Tibesti Volcanic Province (TVP), based on examination of multispectral imagery and digital elevation data acquired from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). Our synthesis of these individual surveys shows that the TVP is made up of several shield volcanoes (up to 80 km diameter) with large-scale calderas, extensive lava plateaux and flow fields, widespread tephra deposits, and a highly varied structural relief. We compare morphometric characteristics of the major TVP structures with other hot spot volcanoes (the Hawaiian Islands, the Galpagos Islands, the Canary and Cape Verdes archipelagos, Jebel Marra (western Sudan), and Martian volcanoes), and consider the implications of differing tectonic setting (continental versus oceanic), the thickness and velocity of the lithosphere, the relative sizes of main volcanic features (e.g. summit calderas, steep slopes at summit regions), and the extent and diversity of volcanic features. These comparisons reveal morphologic similarities between volcanism in the Tibesti, the Galpagos, and Western Sudan but also some distinct features of the TVP. Additionally, we find that a relatively haphazard spatial development of the TVP has occurred, with volcanism initially appearing in the Central TVP and subsequently migrating to both the Eastern and Western TVP regions.

  15. A Treasure Chest of Nanogranites: the Bohemian Massif (Central Europe)

    NASA Astrophysics Data System (ADS)

    Ferrero, S.; O'Brien, P. J.; Walczak, K.; Wunder, B.; Ziemann, M. A.; Hecht, L.

    2014-12-01

    Despite 150 years of investigation of the Bohemian Massif (Central Europe), it is only recently that the investigation of old and new samples displayed the occurrence of tiny portions of crystallized anatectic melt in regional migmatites. These vestiges of magma, called "nanogranites", are natural probes of the partial melting processes in the crust. Original melt composition and water content can be directly analyzed after piston cylinder re-homogenization. When compared to classic re-melting experiments, nanogranites are ideal "natural" experimental charges of anatectic melt. They are encapsulated in peritectic garnet immediately after production - both phases are products of the same partial melting reaction. Sheltered inside garnet, they remain unaffected by the physico-chemical changes which affected the host migmatites during their slow cooling, unlike leucosomes and anatexis-related plutons. Five different case studies of nanogranite-bearing high-grade rocks have been identified so far: three in metapelites from the Moldanubian Zone, and two in metagranitoids from the Granulitgebirge and Orlica-?nie?nik Dome. Their characterization provides insights into how the continental crust melts at different depths, from shallow levels to mantle depths, during different moments of its metamorphic history (prograde vs. decompressional melting). For example, the investigation and experimental re-melting of nanogranites from Grt+Ky leucogranulites (Orlica-?nie?nik Dome) recently provided evidence of prograde melting of metagranitoids under eclogite-facies conditions (T?875C and P~2.7 GPa), close to the stability field of coesite. The melt generated is granitic, hydrous (6 wt% H2O) and metaluminous (ASI=1.03), and is at the moment the "deepest" glass obtained through re-homogenization of primary polycrystalline inclusions in natural rocks. This work confirms that nanogranites in migmatites 1) are a powerful tool to constrain anatexis in natural rocks, and 2) can be found, re-homogenized and investigated in rocks melted under variable PT conditions, even at mantle depths.

  16. Critical Reflection on the Massification of Higher Education in Korea: Consequences for Graduate Employment and Policy Issues

    ERIC Educational Resources Information Center

    Yeom, Min-ho

    2016-01-01

    The paper critically reviews the results of Korean massification in higher education (HE) and focuses on the consequences related to graduate employment. By analysing statistical data and reviewing related articles, this study explores the process of the massification of HE, investigates major factors influencing the expansion, and analyses and

  17. A Library Response to the Massification of Higher Education: The Case of the University of Zambia Library

    ERIC Educational Resources Information Center

    Kanyengo, Christine Wamunyima

    2009-01-01

    This paper looks at the challenges that libraries in Africa face in responding to massification of higher education by discussing the University of Zambia library's response in library and information resources provision. As a result of massification of higher education, libraries have been forced not only to employ new and different strategies to

  18. P- T- t evolution of eclogite/blueschist facies metamorphism in Alanya Massif: time and space relations with HP event in Bitlis Massif, Turkey

    NASA Astrophysics Data System (ADS)

    Çetinkaplan, Mete; Pourteau, Amaury; Candan, Osman; Koralay, O. Ersin; Oberhänsli, Roland; Okay, Aral I.; Chen, Fukun; Kozlu, Hüseyin; Şengün, Fırat

    2016-01-01

    The Alanya Massif, which is located to the south of central Taurides in Turkey, presents a typical nappe pile consisting of thrust sheets with contrasting metamorphic histories. In two thrust sheets, Sugözü and Gündoğmuş nappes, HP metamorphism under eclogite (550-567 °C/14-18 kbar) and blueschist facies (435-480 °C/11-13 kbar) conditions have been recognized, respectively. Whereas the rest of the Massif underwent MP metamorphism under greenschist to amphibolite facies (525-555 °C/6.5-7.5 kbar) conditions. Eclogite facies metamorphism in Sugözü nappe, which consists of homogeneous garnet-glaucophane-phengite schists with eclogite lenses is dated at 84.8 ± 0.8, 84.7 ± 1.5 and 82 ± 3 Ma (Santonian-Campanian) by 40Ar/39Ar phengite, U/Pb zircon and rutile dating methods, respectively. Similarly, phengites in Gündoğmuş nappe representing an accretionary complex yield 82-80 Ma (Campanian) ages for blueschist facies metamorphism. During the exhumation, the retrograde overprint of the HP units under greenschist-amphibolite facies conditions and tectonic juxtaposition with the Barrovian units occurred during Campanian (75-78 Ma). Petrological and geochronological data clearly indicate a similar Late Cretaceous tectonometamorphic evolution for both Alanya (84-75 Ma) and Bitlis (84-72 Ma) Massifs. They form part of a single continental sliver ( Alanya- Bitlis microcontinent), which was rifted from the southern part of the Anatolide-Tauride platform. The P- T- t coherence between two Massifs suggests that both Massifs have been derived from the closure of the same ocean ( Alanya- Bitlis Ocean) located to the south of the Anatolide-Tauride block by a northward subduction. The boundary separating the autochthonous Tauride platform to the north from both the Alanya and Bitlis Massifs to the south represents a suture zone, the Pamphylian- Alanya- Bitlis suture.

  19. Geomorphological and sedimentological evidences in the Western Massif of Picos de Europa since the Last Glaciation

    NASA Astrophysics Data System (ADS)

    Ruiz-Fernández, Jesus; Oliva, Marc; Cruces, Anabela; Lopes, Vera; Conceição Freitas, Maria; García-Hernández, Cristina; Nieuwendam, Alexandre; López-Sáez, José Antonio; Gallinar, David; Geraldes, Miguel

    2015-04-01

    The Western Massif of Picos de Europa includes some of the highest peaks of the Cantabrian Mountains. However, the environmental evolution in this massif since the Last Glaciation is still poorly understood. This research provides a new geochronological approach to the sequence of environmental events occurred here since the maximum expansion of glaciers during the last Pleistocene glaciation. The distribution of the glacial landforms suggests four main stages regarding the environmental evolution in the massif: maximum glacial advance, phase of second maximum glacial expansion, Late Glacial and Little Ice Age. A 5.4-m long sedimentological section retrieved from the kame terrace of Belbín, in a mid-height area of the massif, complements the geomorphological interpretation and provides a continuous paleoenvironmental sequence from this area since the Last Glaciation until nowadays. This section suggests that the maximum glacial expansion occurred at a minimum age of 37.2 ka cal BP, significantly prior to the global Last Glacial Maximum. Subsequently, a new glacial expansion occurred around 18.7-22.5 ka cal BP. The melting of the glaciers after this phase generated a shallow lake in the Belbín depression. Lake sediments do not reveal the occurrence of a cold stage during the Late Glacial, whilst, at higher locations, moraine complexes were formed suggesting a glacier readvance. The terrestrification of this lake started at 8 ka cal BP, when Belbín changed to a peaty environment. At 5 ka cal BP human occupation started at the high lands of the massif according to the existence of charcoal particles in the section. The presence of moraines in the highest northern cirques evidences the last phase with formation of small glaciers in the Western Massif of Picos de Europa, corresponding to the Little Ice Age cold event. Since then, the warming climate has led to the melting of these glaciers.

  20. meeting summary- First Northeast Regional Operational Workshop.

    NASA Astrophysics Data System (ADS)

    Auciello, Eugene P.

    2000-06-01

    The First Northeast Regional Operational Workshop, focusing on hydrometeorology in the northeastern United States, was held 21-23 September 1999 in Albany, New York. Sessions in local and mesoscale modeling, lake-effect snow, hydrology, heavy precipitation forecasting and events, operational techniques, and northeast severe convection were presented. A summary of workshop presentations is provided.

  1. Northeast Texas Workplace Partnership Implementation Program.

    ERIC Educational Resources Information Center

    Northeast Texas Community Coll., Mount Pleasant.

    The Northeast Texas Workplace Partnership Program developed curriculum and training materials based on the literacy requirements of the workplace for two different industries in northeast Texas--Lone Star Steel Company and Pilgrim's Pride Industries. Three advisory committees were established to involve the community, education, and business and

  2. 3. Perspective view of Express Building looking northeast, with Division ...

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

    3. Perspective view of Express Building looking northeast, with Division Street in foreground - American Railway Express Company Freight Building, 1060 Northeast Division Street, Bend, Deschutes County, OR

  3. 11. Exterior detail view of northeast corner, showing stucco finish ...

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

    11. Exterior detail view of northeast corner, showing stucco finish and woodwork details - American Railway Express Company Freight Building, 1060 Northeast Division Street, Bend, Deschutes County, OR

  4. Thermal Properties of paleozoic rocks from the Rhenish Massif

    NASA Astrophysics Data System (ADS)

    Pechnig, Renate; Mottaghy, Darius; Arnold, Juliane; Koch, Andreas; Jorand, Rachel

    2010-05-01

    Large areas of Germany and neighbouring countries are formed by paleozoic rock formations. Beside large outcrops such as the mountain chains of the Rhenish Massif, paleozoic rocks also dominate the subsurface as forming the Northern Germany basement. Still, reliable data sets on thermal properties are rare. To improve this situation, paleozoic rocks samples from outcrops and drillings of North-Rhine Westfalia were investigated. We studied about 230 core samples and obtained information on thermal conductivity, density, porosity and Vp-velocity of the rocks in dry and saturated conditions. In addition, about 50 core plugs were taken for measurements of heat capacity, and P-T-dependent thermal conductivity and thermal diffusivity. Chemical and mineralogical analyses were performed on almost 100 samples. Thus, a unique data set was created, which enables to connect thermal properties to rock porosity and to mineralogical and chemical rock composition. Data analysis revealed the mineralogical composition as the most prominent factor for effective thermal conductivity. This is especially the case for the Carboniferous and Devonian sandstones with quartz contents varying from 35 to 95%. Rock porosity in paleozoic rocks is usually low and it's impact on thermal properties not as significant as the rock mineralogy. Thus, the geometric mixing law is applicable only for rocks, if the mineralogical composition is known. In a similar way, mineralogy affects the temperature and pressure dependence of thermal properties. The strong mineralogical variation of the sandstones leads to non-uniform P-T trends of thermal properties. Only claystones and carbonates show more consistent dependency trends. This allows the definition of rock type specific P-T-correction values. In a following step, the results from the discrete core measurements were combined with continuous borehole geophysical data. Based on the laboratory data, petrophysical models were built up. This allows deriving continuous profiles of rock porosity and volumes of shale, sandstone, coal and carbonates for the different drillings. By this information, the geometric mixing law could be applied to calculate continuous thermal conductivity profiles. These profiles give information on the vertical and lateral heterogeneity of thermal properties and were used to derive statistically proven value ranges for entire stratigraphic units. These values can serve as input parameters for geothermal models and can help to reduce the uncertainty of numerical simulations.

  5. Structure, age, and ore potential of the Burpala rare-metal alkaline massif, northern Baikal region

    NASA Astrophysics Data System (ADS)

    Vladykin, N. V.; Sotnikova, I. A.; Kotov, A. B.; Yarmolyuk, V. V.; Sal'nikova, E. B.; Yakovleva, S. Z.

    2014-07-01

    The Burpala alkaline massif is a unique geological object. More than 50 Zr, Nb, Ti, Th, Be, and REE minerals have been identified in rare-metal syenite of this massif. Their contents often reach tens of percent, and concentrations of rare elements in rocks are as high as 3.6% REE, 4% Zr, 0.5% Y, 0.5% Nb, 0.5% Th, and 0.1% U. Geological and geochemical data show that all rocks in the Burpala massif are derivatives of alkaline magma initially enriched in rare elements. These rocks vary in composition from shonkinite, melanocratic syenite, nepheline and alkali syenites to alaskite and alkali granite. The extreme products of magma fractionation are rare-metal pegmatites, apatite-fluorite rocks, and carbonatites. The primary melts were related to the enriched EM-2 mantle source. The U-Pb zircon ages of pulaskite (main intrusive phase) and rare-metal syenite (vein phase) are estimated at 294 ± 1 and 283 ± 8 Ma, respectively. The massif was formed as a result of impact of the mantle plume on the active continental margin of the Siberian paleocontinent.

  6. Time of formation and genesis of yttrium-zirconium mineralization in the Sakharjok massif, Kola Peninsula

    NASA Astrophysics Data System (ADS)

    Vetrin, V. R.; Skublov, S. G.; Balashov, Yu. A.; Lyalina, L. M.; Rodionov, N. V.

    2014-12-01

    The Kola geotectonic province in the northeastern Fennoscandian Shield accommodates a significant number of alkaline rock massifs differing in age. They are of mantle and mantle-crustal origin (alkali and nepheline syenites, carbonatites) and related to crustal sources (Neoarchean alkali granites). Among them, the Neoarchean Sakharjok nepheline syenite massif is related to the oldest intrusions of this kind bearing yttrium-zirconium mineralization. The crystallization of alkali syenite pertaining to the first intrusive phase of the intrusive Sakharjok massif is dated to 2645 ± 7 Ma, and this implies that this syenite postdated alkali granites (2.66-2.67 Ga). To date the yttrium-zirconium ore, we applied the local U-Pb method to zircon crystals occurring in the mineralized block hosted in nepheline syenite. The earliest fragments of zircon crystallized 1832 ± 7 Ma ago; the age of metamorphism is estimated at 1784 ± 13 Ma. These dates indicate the Paleoproterozoic age of the yttrium-zirconium mineralization, which was formed as a product of fluid reworking of the Neoarchean nepheline syenite of the Sakharjok massif.

  7. Reforming Higher Education in Hong Kong towards Post-Massification: The First Decade and Challenges Ahead

    ERIC Educational Resources Information Center

    Wan, Calvin

    2011-01-01

    The process of reforming Hong Kong's higher education sector commenced in 2001, and the system moved into the post-massification era. Within five years, the post-secondary participation rate for the 17-20 age cohort had increased to 66 per cent. This target was achieved much earlier than the Government had planned. More educational opportunities

  8. New Insights On The Seismotectonics of The French Central Massif and Western France

    NASA Astrophysics Data System (ADS)

    Mazabraud, Y.; Bethoux, N.; Guilbert, J.

    Nowadays, the increase of the number of seismological stations distributed through- out France, allows a re-evaluation of the regional sismotectonics, in particular by pre- cise localisation and computation of focal mecanisms even for small magnitude earth- quakes (Nicolas et al., 1998, Bethoux et al. 1998, Sue et al., 1999; Baroux et al., 2000; Rigo et al., 1999, Souriau et al.,1998). Thanks to the LDG code "FUSION", we have mixed the bulletin data available from several networks, for the French Central massif and Western France, from January 1962 to October 2001. Then, we have divided our study area in different zones: the western Central Massif, a volcanic province (Chaine des Puys), an eocene graben (Limagne), a sedimentary basin (Bassin de Paris), and also the Charente region and the Armorican massif. Using the VELEST code (Kissling et al., 1994), we have obtain for each of those areas, a minimum 1D model (Kissling et al., 1994) which allows to improve the location of the hypocenters. These new hypocenter distributions are correlated with geological structures, and it is possible to associate swarns of events to faults recognized on the field. Some new focal mecha- nisms are computed. Then, an inversion of focal solutions available for each zone al- lows to deduce the regional stress field. Those informations will allow a re-evaluation of the seismotectonics of the northern Central Massif and Western France. In particu- lar, we propose a qualitative analysis of the major faults activity.

  9. The Dongbo and Purang ultramafic massifs in the Yarlung Zangbo suture zone of Tibet: Prospects for large chromite deposits

    NASA Astrophysics Data System (ADS)

    Xiong, F.; Yang, J.; Li, Y.; Liu, Z.; Liu, F.; Xu, X.

    2012-12-01

    Many ultramafic massifs occur along the Neo-Tethyan Yarlung Zangbo suture zone between the Indian and Eurasian plates, and the Dongbo and Purang ultramafic massifs in the western part of the zone are two of the largest. Both of them consist mainly of high-Mg harzburgite (with low pyroxene contents) and dunite with minor lherzolite. Mineral compositions of olivine, orthopyroxene, clinopyroxene, and chromite, as well as whole-rock petrochemistry indicate that these are typical Alpine-type mantle peridotites. Chromium spinels in the lherzolite have Cr#s (=100 x Cr/(Cr+Al)) of 20-30, showing an affinity with abyssal peridotites, whereas those in the harzburgites have Cr#s ranging from 20 to 75, implying later melt-rock reaction. Based on the mineralogy and geochemistry of the rocks, the Dongbo and Purang massifs are interpreted as fragments of MORB lithosphere that were modified in a later SSZ setting. Many massive chromite ores and zones of disseminated mineralization are present in the two massifs, and chromite ores have Cr#s 70-80, similar to those of the hosting dunite. The petrological features and metallogenic environment of the Dongbo and Purang massifs are very similar to those of the Luobusa peridotite massif, which hosts the largest chromite deposit in China. Thus, we propose that the Purang and Dongbo massifs are two potential locations for significant chromite deposits.

  10. Maldzhangarsky rare metal carbonatite massif in the NE-part of the Anabar shield.

    NASA Astrophysics Data System (ADS)

    Vladykin, Nikolai

    2015-04-01

    In the SW part of the Anabar shield Th-anomaly was he drilled by ALROSA company by 6 bore holes to a depth of 100 m, which revealed a new Maldzhangarsky rare metal carbonatite massif (Vladykin 2008). It is oval-shaped and elongated NW to SE having dimensions 4.2 x 2.5 km.. and total square ~ 10.5 km2 Carbonatites are from mean- to fine-grained light-colored. Mineral and chemical composition, tracery, dolomite are ankerite and carbonaties. Besides the carbonate it is composed by phlogopite, apatite, alkali amphibole, rarely magnetite and accessory minerals like pyrochlore, zircon, barito-celestine, rare earth carbonates and apatite, reaching 20-30%. In addition to the prevailing carbonatite the carbonatized pyroxenite xenoliths were found in the drilling cores. Geochemical study of the Maldzhangarsky massif carbonatites indicated the presence of significant quantities of typical carbonatite elements- Sr, Ba, Nb, Ta, P, Y, TRE, which is similar to the carbonatites of the Tomtor massif. Many parts of the massif are the ores for Nb, TR, Sr and P. The highest concentrations based on TRE 100 analyses of Nb-8000 ppm, Y-800 ppm; TRE-4%, Sr-10%,. The REE patterns of carbonanites are highly inclined with the r sharp prevalence of light REE on heavy with a rather steep slope., There are now Eu anomalies which is typical for the mantle carbonitetes, and which evidence for the early fractionation of alkaline carbonatite fluid orliquid from silicate melt. Pair correlation of rare earth elements in carbonatite shows their origin from a single source. The intrusive nature of the drilled carbonatites of Maldzhangarsky massif suggest them to be the top part of the unexposed massif. The belonging of this massif to any genetic type is unclear and needs more detail exploration. RBRF grant (15-05-01005). Vladykin N.v. New rare metal ore karbonatitov province EAST of the Anabarskiy shield. In: Geochemistry of magmatic rocks, St. Petersburg, 2008, pp. 24-27.

  11. Niklas - a Hitherto Unknown Deep Magmatic Massif in the Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Rybakov, M.; Voznesensky, V.; Ben-Avraham, Z.

    2004-12-01

    A Niklas massif was discovered recompiling the gravity and magnetic maps and interpreting in 3-D mode all the available data in the area around Eratosthenes Seamount (ESM). The updated datasets clearly show two partially superimposed magnetic dipoles, which also correspond well to disturbances in the gravity field. The pronounced Eratosthenes magnetic anomaly (EMA) is only the positive part of the southeastern dipole. There is no large gravity anomaly here, however the specific gravity pattern corresponds to the magnetic body. The northwestern `magnetic dipole coincides with a prominent (about of 100mGal) gravity high that was recently delineated by Russian geophysicists. Such grav/mag combination allowed us to interpret the anomalies as being caused by a hitherto unknown dense and magnetic body which we have named the Niklas massif. The parameters and depth of causative bodies were calculated by inverse programs and forward modeling using the seismic refraction and reflection constraints. The reliability of the final model was verified using forward modeling. The magnetic data were interpreted by assuming an induced magnetization as the main magnetizing factor. The final model consists of two large compact features oriented NE-SW and located south of the Cyprian arc,as the Eratosthenes and Niklas bodies. The gravity and magnetic pattern of the Niklas is typical for the ophiolite massifs of the Eastern Mediterranean and Southern Turkey (Troodos, Hatay, Antalya). Based on this likeness we assume the Niklas composed by dense and magnetic ophyolites. This large (~100*75km) deep-seated (~7km) thick (~7km) massif is located ~95km southwest of Cyprus. We consider the Niklas as the south-most fragment of the large allochthonous ophiolite thrust slab including the Troodos massif. The tectonic situations of the Niklas area and the central segment of the Cyprian Arc are similar to that of the Eastern Taurus, Bayer-Bassit and Hatay areas. Interaction of the large Late Cretaceous overthrusts, younger Miocene reverse faults inclined mainly to north and Miocene- Pliocene normal faults and strike-slip faults revealed to the existing tectonic pattern. A system of reverse faults of the Cyprian arc separates the Niklas massif from the Troodos. This system is the main reason of the considerably lower level of the Niklas massif relative to the Troodos one. A pronounce tectonic boundary separates probably Niklas area from the Eratosthenes Block. Upper Cretaceous section of this block is sterile of ophiolites suggesting that during the Mesozoic the paleo-Eratosthenes area was located far from present-day position.

  12. Seismicity of the Atlantis Massif detachment fault, 30N at the Mid-Atlantic Ridge

    NASA Astrophysics Data System (ADS)

    Collins, John A.; Smith, Deborah K.; McGuire, Jeffrey J.

    2012-10-01

    At the oceanic core complex that forms the Atlantis Massif at 30N on the Mid-Atlantic Ridge, slip along the detachment fault for the last 1.5-2 Ma has brought lower crust and mantle rocks to the seafloor. Hydroacoustic data collected between 1999 and 2003 suggest that seismicity occurred near the top of the Massif, mostly on the southeastern section, while detected seismicity along the adjacent ridge axis was sparse. In 2005, five short-period ocean bottom seismographs (OBS) were deployed on and around the Massif as a pilot experiment to help constrain the distribution of seismicity in this region. Analysis of six months of OBS data indicates that, in contrast to the results of the earlier hydroacoustic study, the vast majority of the seismicity is located within the axial valley. During the OBS deployment, and within the array, seismicity was primarily composed of a relatively constant background rate and two large aftershock sequences that included 5 teleseismic events with magnitudes between 4.0 and 4.5. The aftershock sequences were located on the western side of the axial valley adjacent to the Atlantis Massif and close to the ridge-transform intersection. They follow Omori's law, and constitute more than half of the detected earthquakes. The OBS data also indicate a low but persistent level of seismicity associated with active faulting within the Atlantis Massif in the same region as the hydroacoustically detected seismicity. Within the Massif, the data indicate a north-south striking normal fault, and a left-lateral, strike-slip fault near a prominent, transform-parallel, north-facing scarp. Both features could be explained by changes in the stress field at the inside corner associated with weak coupling on the Atlantis transform. Alternatively, the normal faulting within the Massif might indicate deformation of the detachment surface as it rolls over to near horizontal from an initial dip of about 60 beneath the axis, and the strike-slip events may indicate transform-parallel movement on adjacent detachment surfaces.

  13. Crustal structure of the Bohemian Massif in the light of seismic refraction data

    NASA Astrophysics Data System (ADS)

    Hrubcova, Pavla

    2010-05-01

    The Bohemian Massif is one of the largest stable outcrops of pre-Permian rocks in Central and Western Europe. It forms the easternmost part of the Variscan Belt, which developed approximately between 500 and 250 Ma during a stage of large-scale crustal convergence, collision of continental plates and microplates, and possibly also subduction. It consists mainly of low- to high-grade metamorphic and plutonic Palaeozoic rocks. The area of the Bohemian Massif can be subdivided into various tectonostratigraphic units separated by faults, shear zones or thrusts trending roughly in a SW-NE direction, and reflecting varying influence of the Cadomian and Variscan orogenies: the Saxothuringian, Tepl-Barrandian, Moldanubian and Moravo-Silesian. Geographically, it comprises the area of the Czech Republic, partly Austria, Germany and Poland. While the post-collisional history of the Variscan Bohemian Massif is relatively clear, the kinematics of plate movements before and during collision is still subject of debates. To investigate such a complex structure, the Bohemian Massif has been covered by a network of seismic experiments as a result of a massive international cooperative effort in central Europe. Detailed analyses of the data from the main profiles of the CELEBRATION 2000, ALP 2002, and SUDETES 2003 refraction and wide-angle reflection seismic experiments show crustal and uppermost mantle structure of the massif and delimit the continuation of various tectonic units in depth. The differences in seismic velocities reflect, to some extent, the structural variances and give some indications for tracing of crust-forming processes during individual tectonic events. Lower crust in the Saxothuringian exhibits complicated structure, ranging from a highly reflective lower crustal layer above Moho with a strong velocity contrast at the top of this layer. Another possible explanation can be a double Moho or the Moho with some lateral topography. This complicated lower crust extends in a depth range of 26-35 km and is characteristic for the Saxothuringian unit, which was subject to the eastward subduction. The Moldanubian in the central part usually seen as the root of the Bohemian Massif is characterized by the deepest (39 km) and the most pronounced Moho within the whole massif with a strong velocity contrast. The lower crust at the eastern margin of the Bohemian Massif is characterized by elevated velocities and high velocity gradient, which seems to be a characteristic feature of the Moravo-Silesian. References Hrubcov, P., and W. H. Geissler. The Crust-Mantle Transition and the Moho beneath the Vogtland/West Bohemian Region in the Light of Different Seismic Methods, Stud. Geophys. Geod., 53, 275--294, 2009 Hrubcov P., P. ?roda, and CELEBRATION 2000 Working Group, Crustal structure at the easternmost termination of the Variscan belt based on CELEBRATION 2000 and ALP 2002 data, Tectonophysics, 460, 55-75, doi:10.1016/j.tecto.2008.07.009, 2008 Hrubcov P., P. ?roda, A. pi?k, A. Guterch, M. Grad, R. Keller, E. Brckl and H. Thybo, Crustal and uppermost mantle structure of the Bohemian Massif based on data from CELEBRATION 2000 Experiment, J. Geophys. Res., 110, B11305, doi:10.1029/2004JB003080, 2005 Hrubcov, P., P. ?roda, M. Grad, W.H. Geissler, A. Guterch, J. Vozr, E. Heged?s, and Sudetes 2003 Working Group. From the Variscan to the Alpine Orogeny - crustal structure of the Bohemian Massif and Western Carpathians in the light of the SUDETES 2003 seismic data, GJI, submitted

  14. Northeast Regional Planetary Data Center

    NASA Technical Reports Server (NTRS)

    Schultz, Peter H.; Saunders, Stephen (Technical Monitor)

    2005-01-01

    In 1980, the Northeast Planetary Data Center (NEPDC) was established with Tim Mutch as its Director. The Center was originally located in the Sciences Library due to space limitations but moved to the Lincoln Field Building in 1983 where it could serve the Planetary Group and outside visitors more effectively. In 1984 Dr. Peter Schultz moved to Brown University and became its Director after serving in a similar capacity at the Lunar and Planetary Institute since 1976. Debbie Glavin has served as the Data Center Coordinator since 1982. Initially the NEPDC was build around Tim Mutch's research collection of Lunar Orbiter and Mariner 9 images with only partial sets of Apollo and Viking materials. Its collection was broadened and deepened as the Director (PHS) searched for materials to fill in gaps. Two important acquisitions included the transfer of a Viking collection from a previous PI in Tucson and the donation of surplused lunar materials (Apollo) from the USGS/Menlo Park prior to its building being torn down. Later additions included the pipeline of distributed materials such as the Viking photomosaic series and certain Magellan products. Not all materials sent to Brown, however, found their way to the Data Center, e.g., Voyager prints and negatives. In addition to the NEPDC, the planetary research collection is separately maintained in conjunction with past and ongoing mission activities. These materials (e.g., Viking, Magellan, Galileo, MGS mission products) are housed elsewhere and maintained independently from the NEPDC. They are unavailable to other researchers, educators, and general public. Consequently, the NEPDC represents the only generally accessible reference collection for use by researchers, students, faculty, educators, and general public in the Northeast corridor.

  15. Petrology of UHP calcite marble from the Kokchetav Massif

    NASA Astrophysics Data System (ADS)

    Aoki, K.; Adachi, T.; Kikuchi, M.; Ogasawara, Y.

    2004-12-01

    In the Kumdy-kol area, Kokchetav Massif, northern Kazakhstan, three types of UHP marbles have been described: diamond-bearing dolomite marble, Ti-clinohumite-bearing dolomitic marble (Ogasawara et al., 2000) and titanite-bearing calcite marble (Ogasawara et al., 2002). UHP calcite marble is distinguished from other types of UHP marbles by pure calcite (after aragonite) as a dominant carbonate phase. This calcite marble has unique evidence of UHP metamorphism; titanite with coesite exsolution and its precursor compositions indicated that the peak P-T conditions was > 6 GPa and 980-1250 C (Ogasawara et al., 2000; 2002). This rock shows typical granoblastic texture consisting of calcite, diopside, K-feldspar, titanite and symplectite (diopside + zoisite) after garnet. The peak assemblage was aragonite + diopside + K-feldspar + garnet + titanite. Based on the phase relations in the system CaO-MgO-TiO2-SiO2-CO2-H2O, aragonite + diopside + rutile tie-triangle is stable under UHP conditions and divides the compositional space into dolomite-bearing or dolomite-free tetrahedrons (Kikuchi et al., 2003). The presence of titanite in calcite marble means that P-T condition was located at the right-hand side of the reaction rutile + aragonite + coesite = titanite + CO2. Previously described titanite-bearing calcite marble is diamond-free (A-type) and is characterized by titanite with coesite exsolution (Ogasawara et al., 2002). Recently, we found a small amount of diamond in calcite marble (B-type) that is characterized by microdiamond in diopside, and by the lack of K-feldspar and low amount of titanite. No diamond occurs in titanite. Rutile, aragonite and calcite inclusions in titanite were found in titanite of B-type calcite marble. These three inclusion phases in titanite that were confirmed by laser Raman spectroscopy are the evidence for titanite formation reaction described above. This titanite forming reaction occurs at extremely low XCO2 conditions as 0.02. In B-type calcite marble, microdiamond occurs locally and its amount is low; only 61 grains were found in two thin sections. Distributions of titanite, K-feldspar and diamond are heterogeneous and seem to form layers. Diamond occurs in the domain where amounts of titanite and K-feldspar are relatively low. Low amount of microdiamond may be related with extremely low-XCO2 condition under UHP metamorphism. References Ishida et al. (2003: Journal of Metamorphic Geology, Vol. 21, p. 515-522. Kikuchi et al. (2003): EOS Transactions AGU, Vol. 84, F1532. Ogasawara et al. (2000): The Island Arc, Vol. 9, p 400-416. Ogasawara et al. (2002): American Mineralogist, Vol. 87, p. 454-461.

  16. Paleomagnetic results from Cenozoic volcanics of Lusatia, NW Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Schnabl, P.; Cajz, V.; Tietz, O.; Buechner, J.; Suhr, P.; Pecskay, Z.; Cizkova, K.

    2013-05-01

    Lusatia is situated in the NE continuation of the Ohre Rift (OR) behind Lusatian Overtrust. Compared to the neighbouring volcanic complex of the ?esk stredohor Mts. (CS) inside the OR. The scattered occurrences of basaltic bodies in Lusatia are spread on wider area. This can be caused by different tectonic development of the regions and from derived erosional conditions. The Lusatian Overtrust, high-order tectonic structure running across the course of the OR, separates Lusatian region into two different geological areas where Cretaceous sediments or granodiorites of Lusatian Massif represent the country rock of the Cenozoic volcanism, respectively. The age of volcanic activity ranges from 19 to 33 Ma, it's proved by newly obtained Ar-Ar data from Freiberg and K-Ar data from Debrecen. Forty two scattered remnants of Cenozoic volcanic products were sampled to get paleomagnetic data. The superficial volcanics with detectable geological position and volcanology were chosen preferentially, several dykes and separate vents were sampled as well. Paleomagnetic research was processed on more than 500 samples which were demagnetized using alternate field in the range 0-80 mT. Q-ratio was counted to prevent the lightning influence - solitary volcanic occurrences build positive morphology and thus, they are prone to be targeted by lightnings. The values of Q-ratio predominantly span from 0.1 to 7.0; those samples having the value over 10, were excluded for evaluation. The mean paleomagnetic direction (MPD) was acquired from several samples on each sampling site. Declination and Inclination show values of 11.8 deg and 62.7 deg (?95 = 9.3 deg) for normal polarity, or 182.1 deg and -59.2 deg (?95 = 6.1 deg) for reverse polarity, respectively,The corresponding paleolatitude of 41.9 deg was counted from the Inclination. This is 1000 km to the South, compared to recent position. The dispersions of the MPD are relatively wide. This coincides well with the idea of long-lasting volcanic activity in Lusatia and supports the radiometric results. Duration of volcanic activity in Lusatia is similar to CS volcanic complex in OR and differs from these which are outside this structure. In combination of reversal test and the wide dispersion of MPD, the centred secular variation was proved. It allowed counting of the virtual geomagnetic pole (VGP) position on coordinates 79.9 N and 167.5 E (dp = 6.1 deg, dm = 7.9 deg), which corresponds with the Late Tertiary apparent polar wander path for Europe. The VGP counted from volcanics in Lusatia is relatively close to the data obtained mainly from the CS Volcanic Complex (85.09 N and 160.88 E). The paleomagnetic results of volcanic rocks from Lusatia, obtained up to now, show great similarity to that ones from the CS Volcanic Complex. This is another argument for an idea of joint volcanic development of these regions. It also contributes to the entitled use of the CS lithostratigraphic units in Lusatia.

  17. Geological setting and petrogenesis of symmetrically zoned, miarolitic granitic pegmatites at Stak Nala, Nanga Parbat - Haramosh Massif, northern Pakistan

    USGS Publications Warehouse

    Laurs, B.M.; Dilles, J.H.; Wairrach, Y.; Kausar, A.B.; Snee, L.W.

    1998-01-01

    Miarolitic granitic pegmatites in the Stak valley in the northeast part of the Nanga Parbat - Haramosh Massif, in northern Pakistan, locally contain economic quantities of bi- and tricolored tourmaline. The pegmatites form flat-lying sills that range from less than 1 m to more than 3 m thick and show symmetrical internal zonation. A narrow outer or border zone of medium-to coarse-grained oligoclase - K-feldspar - quartz grades inward to a very coarse-grained wall zone characterized by K-feldspar - oligoclase - quartz - schorl tourmaline. Radiating sprays of schorl and flaring megacrysts of K-feldspar (intermediate microcline) point inward, indicating progressive crystallization toward the core. The core zone consists of variable mixtures of blocky K-feldspar (intermediate microcline), oligoclase, quartz, and sparse schorl or elbaite, with local bodies of sodic aplite and miarolitic cavities or "pockets". Minor spessartine-almandine garnet and lo??llingite are disseminated throughout the pegmatite, but were not observed in the pockets. The pockets contain well-formed crystals of albite, quartz, K-feldspar (maximum microcline ?? orthoclase overgrowths), schorl-elbaite tourmaline, muscovite or lepidolite, topaz, and small amounts of other minerals. Elbaite is color-zoned from core to rim: green (Fe2+- and Mn2+-bearing), colorless (Mn2+-bearing), and light pink (trace Mn3+). Within ???10 cm of the pegmatites, the granitic gneiss wallrock is bleached owing to conversion of biotite to muscovite, with local quartz and albite added. Schorl is disseminated through the altered gneiss, and veins of schorl with bleached selvages locally traverse the wallrock up to 1 m from the pegmatite contact. The schorl veins can be traced into the outer part of the wall zone, which suggests that they formed from aqueous fluids derived during early saturation of the pegmatite-forming leucogranitic magma rich in H2O, F, B, and Li. Progressive crystallization resulted in a late-stage sodic magma and abundant aqueous fluids. Two late stages of volatile escape are recognized: the first stage caused pressure-quenching of the last magma, which produced aplite and caused albitization (An3 to An8) of earlier crystallized K-feldspar and oligoclase. The second stage, released during the rupture of miarolitic cavities, produced platy albite ("cleavelandite," An1) locally associated with F-rich moscovite and elbaite. Albitization is likely due to cooling of alkali-fluoride-dominated fluids at less than 2 kbar pressure. The pegmatites are derived from Himalayan leucogranitic magma emplaced prior to 5 Ma into granulitic gneiss that was at 300?? to 550??C and 1.5 to 2 kbar. The pegmatites were emplaced during uplift of the Haramosh Massif, since they cross-cut ductile normal faults but are cut by brittle normal faults. Economically important pink tourmaline mineralization formed in pockets concentrated near the crest of a broad antiform, as a result of trapping of late magmatic aqueous fluids that had become Fe-poor owing to the prior crystallization of schorl.

  18. Research of dynamical Characteristics of slow deformation Waves as Massif Responses on Explosions

    NASA Astrophysics Data System (ADS)

    Hachay, Olga; Khachay, Oleg; Shipeev, Oleg

    2013-04-01

    The research of massif state with use of approaches of open system theory [1-3] was developed for investigation the criterions of dissipation regimes for real rock massifs, which are under heavy man-caused influence. For realization of that research we used the data of seismic catalogue of Tashtagol mine. As a result of the analyze of that data we defined character morphology of phase trajectories of massif response, which was locally in time in a stable state: on the phase plane with coordinates released by the massif during the dynamic event energy E and lg(dE/dt) there is a local area as a ball of twisted trajectories and some not great bursts from that ball, which are not greater than 105 joules. In some time intervals that burst can be larger, than 105 joules, achieving 106 joules and yet 109 joules. [3]. Evidently there are two reciprocal depend processes: the energy accumulation in the attracted phase trajectories area and resonance fault of the accumulated energy. But after the fault the system returns again to the same attracted phase trajectories area. For analyzing of the thin structure of the chaotic area we decided to add the method of processing of the seismic monitoring data by new parameters. We shall consider each point of explosion as a source of seismic or deformation waves. Using the kinematic approach of seismic information processing we shall each point of the massif response use as a time point of the first arrival of the deformation wave for calculation of the wave velocity, because additionally we know the coordinates of the fixed response and the coordinates of explosion. The use of additional parameter-velocity of slow deformation wave propagation allowed us with use method of phase diagrams identify their hierarchic structure, which allow us to use that information for modeling and interpretation the propagation seismic and deformation waves in hierarchic structures. It is researched with use of that suggested processing method the thin structure of the chaotic area for two responses of the massif on a high energetic explosion in the northern and southern parts of it. The results are significant for understanding the high energetic rock shock and evaluation a criterion for massif stability estimation. The work is supported by the grant RFBR 10-05-00013 and Integration Project 2012-2014 with SB RAS Key words: massif response, slow deformation waves, seismic mine catalogue, analyze of observed data, phase diagrams. References 1. Naimark Y.I.,Landa P.S. Stochastic and chaotic oscillations//Moscow: Book House "LIBROKOM", 2009.-p.424. 2. Chulichkov A.I. Mathematical models of nonlinear dynamics.Moscow: Fizmatlit, 2003.-p.294. 3. Hachay O.A.,Khachay O.Y.,Klimko V.K.,Shipeev O.V. Reflection of synergetic features of rock massif state under man-caused influence after the data of mine seismological catalogue.// Mine informational and analytical bulletin MSMU,6, 2010,p.259-271.

  19. Enhancing Scientific Literacy in the Northeast Kingdom

    NASA Astrophysics Data System (ADS)

    Blackwell, John; Moss, B.; Wanzer, S.

    2014-01-01

    An observatory in the Northeast Kingdom of Vermont opens to assist surrounding elementary and high schools with science literacy using astronomy as a capstone science, introducing students to advanced instrumentation, scientific method and data manipulation skills.

  20. Northeast Clean Energy Application Center

    SciTech Connect

    Bourgeois, Tom

    2013-09-30

    From October 1, 2009 through September 30, 2013 (“contract period”), the Northeast Clean Energy Application Center (“NE-CEAC”) worked in New York and New England (Connecticut, Rhode Island, Vermont, Massachusetts, New Hampshire, and Maine) to create a more robust market for the deployment of clean energy technologies (CETs) including combined heat and power (CHP), district energy systems (DES), and waste heat recovery (WHR) systems through the provision of technical assistance, education and outreach, and strategic market analysis and support for decision-makers. CHP, DES, and WHR can help reduce greenhouse gas emissions, reduce electrical and thermal energy costs, and provide more reliable energy for users throughout the United States. The NE-CEAC’s efforts in the provision of technical assistance, education and outreach, and strategic market analysis and support for decision-makers helped advance the market for CETs in the Northeast thereby helping the region move towards the following outcomes: • Reduction of greenhouse gas emissions and criteria pollutants • Improvements in energy efficiency resulting in lower costs of doing business • Productivity gains in industry and efficiency gains in buildings • Lower regional energy costs • Strengthened energy security • Enhanced consumer choice • Reduced price risks for end-users • Economic development effects keeping more jobs and more income in our regional economy Over the contract period, NE-CEAC provided technical assistance to approximately 56 different potential end-users that were interested in CHP and other CETs for their facility or facilities. Of these 56 potential end-users, five new CHP projects totaling over 60 MW of install capacity became operational during the contract period. The NE-CEAC helped host numerous target market workshops, trainings, and webinars; and NE-CEAC staff delivered presentations at many other workshops and conferences. In total, over 60 different workshops, conferences, webinars, and presentation were hosted or delivered during the contract period. The NE-CEAC also produced publically available educational materials such as CHP project profiles. Finally, the NE-CEAC worked closely with the relevant state agencies involved with CHP development. In New York, the NE-CEAC played an important role in securing and maintaining funding for CHP incentive programs administered by the New York State Energy Research Development Authority. NE-CEAC was also involved in the NYC Mayor's Office DG Collaborative. The NECEAC was also named a strategic resource for the Connecticut Department of Energy and Environmental Protection’s innovative Microgrid Pilot Program.

  1. Pliocene northeast African vegetation change

    NASA Astrophysics Data System (ADS)

    Liddy, H.; Sieracki, A.; Feakins, S. J.

    2012-12-01

    Plant leaf wax molecular fossils have yielded key insights into forest-grassland transitions in northeast Africa. The stable carbon isotopic composition (?13C) of sedimentary leaf waxes (including n-alkanoic acids) records variations in the proportions of plants using the C3 (Calvin-Benson) pathway including trees, most shrubs and cool-season grasses versus the C4 (Hatch-Slack) pathway including warm-season grasses and sedges. Here we apply this technique to marine sediments from the Gulf of Aden to characterize northeast African environmental variability during the Pliocene. We sample DSDP Site 231 integrating 3kyr intervals to generate a high-resolution reconstruction spanning 3.7-5.3Ma. The ?13C compositions of downcore C30 n-alkanoic acid analyses average -27.5 (?=1.2, n=177), ranging between -30.2 to -24.3 with repeated oscillations in the proportions of C4 biomass, presumably corresponding to the eccentricity and precessional modulation of insolation acting on monsoonal precipitation. Although ?13C values cannot be uniquely translated to C4 biomass given the spread in the C3 'endmember', we find complimentary evidence for proportions of C4 biomass from the isotopic spread of the n-alkanoic homologues (n-C28 to n-C32). Comparison to pollen data indicates that at times of low ?13C values, complete forest cover remains unlikely given the presence of grass pollen - taken together these records indicate the presence of C3 grasses. By evaluating our longer record from this site, as well as the terrestrial soil carbonate record, we find the Pliocene has low C4 proportions in comparison to higher proportions in Pleistocene and even late Miocene times. Intriguingly this drop in C4 plant biomass may correspond to a period of elevated atmospheric pCO2. Our ongoing reconstructions are of interest both for constraining environments of hominin evolution and tropical climate variability prior to the onset of Northern Hemisphere Glaciation, in particular during this Pliocene time period of interest as a 'modest greenhouse' world.

  2. Long lasting paleolandscapes stability of the French Massif Central during the Mesozoic

    NASA Astrophysics Data System (ADS)

    Ricordel-Prognon, C.; Thiry, M.; Theveniaut, H.; Lagroix, F.

    2009-04-01

    Regional geodynamical evolution is mainly constrained by the sedimentary record in the basins. Usually, little is known about geodynamics of the peripheral areas and even less on the evolution of the basement areas. Continental unconformities are essential to estimate erosion rates of basement and to model the crustal dynamics that control subsidence of surrounding sedimentary basins but also uplift and erosion on their edges. Dating such unconformities has always been the stumbling block while it is a prerequisite to constrain geodynamical models. Paleomagnetism has been proven as a suitable tool to date ferrugineous paleoweathering features. The method has been applied to paleoweathering occurrences resting on the Massif Central crystalline basement as well as to paleoweathering features affecting the crystalline basement itself. The remanence measurements were obtained at the Paleomagnetic Laboratory of the Institut Physique du Globe de Paris and data analyses were carried out using PaleoMac 5 software (Cogné, 2003). Relative dating of the paleoweathering profiles have been acquired by comparing the recorded paleomagnetic poles from the analysed samples to the apparent polar wandering path of the Eurasian plate (Edel et Duringer, 1997 ; Besse and Courtillot, 2003). Thick red kaolinitic formations rest locally on the Massif Central basement. They are generally bounded by the Tertiary grabens and buried by the Oligocene formations. Thus these azoic red formations have classically been ascribed to the "Siderolithic" formations of Eocene-Oligocene age. They show many pedogenic features (termites burrows, illuviation and hydromorphic features and nodules) and strong relationships with paleolandscape organisation (leaned against fault scarps, infilling paleovalleys, etc.). Macro and micromorphological arrangements show that these formations are in situ paleosols. Paleomagnetic ages range from 160 Ma (Late Jurassic) in the centre of the Massif Central to 140 Ma (Early Cretaceous) in the northern parts of the massif (Ricordel et al., 2005; Ricordel, 2007;). These new ages, fairly older than the expected ones, bring considerable changes in the palaeogeographic evolution of the Massif Central during Mesozoic and Cenozoic. Basement rocks (granites, gneiss, rhyolites and even Permo-Carboniferous sediments) show often pinkish facies throughout the Massif Central. It has been shown that these pink facies are albitised (mainly pseudomorphic replacement of the primary plagioclases into albite and alteration of the biotite into chlorite) (Schmitt, 1992; Parcerisa et al., 2009). These albitised facies are arranged in a clear succession against (?) the Triassic unconformity that gives significant constraints about their development in relation with the Triassic palaeosurface. Secondary albite and chlorite contain minute hematite inclusions, which have been dated, using paleomagnetism, to be Triassic in age (245 Ma) (Ricordel et al., 2007). Given that the alterations are of the same age as the unconformity, it then follows that the albitised facies be related to the Triassic palaeosurface and be used to track back the Triassic palaeosurface through wide crystalline areas, even far away from the Mesozoic cover. Palaeomagnetic analyses allowed dating a large range of paleoweathering features for which no objective datings were previously available. Spatial and temporal distributions of the paleoweathering features and related unconformities provide key arguments to unravel the geodynamic evolution of the Massif Central. Triassic, Late Jurassic and Tertiary unconformities are superimposed on large areas of the Massif Centrall. This implies very little erosion of the crystalline basement since Triassic time, as shown by the widespread preservation of the Triassic albitized facies. Since the red kaolinitic paleosols of Late Jurassic/Early Cretaceous age rest directly on the basement rocks, large areas of the Massif Central were uncovered at this period, and more importantly no Jurassic cover was preserved (if such a cover was even deposited?) on the massif. Consequently, the Massif Central probably never did support an important (more than 500 m) sedimentary cover during the Mesozoic. These paleosurface ages provide important constraints to crustal dynamics modeling. Identification and dating of the successive continental unconformities are evidence for long lasting continental evolution and landscape stability of large areas of the Massif Central during the Mesozoic. The alternative hypothesis was that the Massif Central was subsidizing during Mesozoic time and covered with a 2,000 m thick sedimentary series, which was fairly quickly eroded during early Tertiary (Barbarand et al., 2001). In the future, making substantial progress in paleoweathering profiles dating, especially in the scope of improving time resolution, will allow attempting efficient correlation between the continental records and the diverse processes involved in their development (eustatism, climate, global and regional tectonics). Moreover, progress in dating paleoweathering features and continental azoic deposits, will allow to develop a "continental stratigraphy" of climatic and geomorphological events and to establish a mass balances between weathering/erosion weathering/erosion on land and deposition in basins. References Barbarand J., Lucazeau F., Pagel M., Séranne M., 2001, Burial and exhumation history of the south-eastern Massif Central (France) constrained by apatite fission track thermochronology. Tectonophysics, 335, 3-4, p. 275-290. Besse, J., Courtillot, V., 2003. Apparent true polar wander and the geometry of the geomagnetic field over the last 200 Myr: Correction: Journal of Geophysical Research, 108, p. 2300. Cogné, J.P., 2003. PaleoMac: a MacintoshTM application for treating paleomagnetic data and making plate reconstructions. Geochemistry Geophysics Geosystems, 4 (1), 1007. Edel J.B., Duringer P., 1997, The apparent polar wander path of the European plate in Upper Triassic-Lower Jurassic times and the Liassic intraplate fracturing of the Pangea : New palaeomagnetic constraints from NW France and SW Germany. Geophysical Journal International 128 (2), 331-344. Parcerisa D., Thiry M., Schmitt J.-M., 2009, Albitization related to the Triassic unconformity in igneous rocks of the Morvan Massif (France), International Journal of Earth Sciences, DOI: 10.1007/s00531-008-0405-1 Ricordel C, Parcerisa D, Thiry M, Moreau M-G, Gómez-Gras D (2007) Triassic magnetic overprints related to albitization in granites from the Morvan massif (France). Palaeogeogr Palaeoclimatol Palaeoecol 251: 268-282 Ricordel C. (2007) - Datations par paléomagnétisme des paléoaltérations du Massif central et de ses bordures : implications géodynamiques. Thèse Ecole Nat. Sup. Des Mines de Paris, Paris, 172 p. Ricordel C., Thiry M., Moreau M.-G., Théveniaut H. (2005) Paleomagnetic datings on "Siderolithic" paleoweathering profiles along French Massif Central. European Geosciences Union, Vienne, Autriche, 24-29 avril, Geophysical Research Abstracts, vol. 7, 06631, 6 p. Schmitt J.M. (1992) Triassic albitization in southern France: an unusual mineralogical record from a major continental paleosurface In: Schmitt JM, Gall Q (eds). Mineralogical and geochemical records of paleoweathering. Paris, ENSMP, Mem Sci Terre 18, pp 115-131

  3. Integrating lawsonite bearing eclogite and blueschist into the structural evolution of the Sivrihisar massif

    NASA Astrophysics Data System (ADS)

    Davis, P. B.

    2009-12-01

    Lawsonite eclogite and blueschist-facies rocks occur in contact with metasedimentary host rocks in the Sivrihisar massif, part of the Tavsanli Zone of western Turkey, provide new context to the Neo-Tethyan subduction and exhumation processes that occurred prior to and exhumation that occured during the Cretaceous Anatolide continental collision and basin closure. The Sivrihisar massif is comprised of four WNW-ESE striking belts dominated by metasedimentary schist and marble with lesser amounts of metabasalt that have a bulk composition equivalent to NMORB. Metabasalts in three of the four belts record decreasing maximum pressure conditions (P-max) from ~ 26 kbar from lawsonite eclogite and ~ 18 kbar from epidote eclogite in the northern most Halilbagi belt, 15-16 kbar from lawsonite-epidote blueschist in the central Karacaoren belt, and 8-12 kbar from incipient blueschist facies on epidote + chlorite greenschist facies metabasalt in the Kertek belt to the south. Most rocks contain a pervasive foliation, (S1) parallel to compositional layering (S0), and mineral lineations (stretched and/or aligned) composed of minerals such as quartz, omphacite, sodic-amphibole, lawsonite, pressure shadows on garnet and lawsonite. Inclusions trails in garnet and lawsonite suggest that S0/S1 is a composite fabric that records pre- to post P-max in the Halilbagi and Karacaoren belts. S0/S1 predates incipient blueschist in the Kertek belt. Folds (F2) of S0/S1 are typically asymmetric and tight to isoclinal. F2 folds are south-vergent and moderately easterly plunging in the Halilbagi and northern portion of the Karacaoren belts. F2 axes become more horizontal from north to south across the Karacaoren belt. F2s are recumbent in the Kertek belt. F3 folds are consistently upright open to closed with NNW plunging axes across the massif. Fibrous calcite, interpreted to be pseudomorph after aragonite, occurs parallel to F3 fold axes across the massif. Shear sense indicators from field observations and asymmetric type-I cross girdle of quartz c-axes obtained from electron backscatter diffraction (EBSD) show top to the south thrusting for much of the massif with the exception of the far northern margin. The Halilbagi belt was thrust onto the Karacaoren belt possibly below a depth of 45 km during extrusion along the subduction channel. Exhumation from this structural level may have coincided with the arrival of the Anatolide micro-continent into the subduction zone at approximately 70 Ma. The homogeneous orientation of calcite fibers and F3s across the Massif suggests that assembly occurred at blueschist conditions before exhumation through the aragonite-calcite transition ~ 350 degrees C above 8 kbar.

  4. Northeast View From Pathfinder Lander

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This panorama of the region to the northeast of the lander was constructed to support the Sojourner Rover Team's plans to conduct an 'autonomous traverse' to explore the terrain away from the lander after science objectives in the lander vicinity had been met. The large, relatively bright surface in the foreground, about 10 meters (33 feet) from the spacecraft, in this scene is 'Baker's Bench.' The large, elongated rock left of center in the middle distance is 'Zaphod.'

    This view was produced by combining 8 individual 'Superpan' scenes from the left and right eyes of the IMP camera. Each frame consists of 8 individual frames (left eye) and 7 frames (right eye) taken with different color filters that were enlarged by 500% and then co-added using Adobe Photoshop to produce, in effect, a super-resolution panchromatic frame that is sharper than an individual frame would be.

    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 IMP was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  5. North Massif lithologies and chemical compositions viewed from 2-4 mm particles of soil sample 76503

    NASA Technical Reports Server (NTRS)

    Bishop, Kaylynn M.; Jolliff, Bradley L.; Korotev, Randy L.; Haskin, Larry A.

    1992-01-01

    We identify the lithologic and compositional components of soil 76503 based on INAA of 243 2-4-mm particles and 72 thin sections from these and associated 1-2-mm particles (76502). We present a statistical distribution of the major compositional types as the first step of a detailed comparative study of the North and South Massifs. The soil sample was collected well away from any boulder and is more representative of typical North Massif material than any single large rock or boulder sample. So far, our examination of the 76503 particles has provided a better definition of precursor igneous lithologies and their petrogenetic relationships. It has enabled us to refine the nature of mixing components for the North Massif less than 1-mm fines. It has confirmed the differences in lithologies and their proportions between materials of the North and South Massifs; e.g., the North Massif is distinguished by the absence of a 72275-type KREEP component, the abundance of a highly magnesian igneous component, and the absence of certain types of melt compositions found in the South Massif samples.

  6. Results of dating of thorianite and baddeleyite from carbonatites of the Guli massif, Russia

    NASA Astrophysics Data System (ADS)

    Malich, K. N.; Khiller, V. V.; Badanina, I. Yu.; Belousova, E. A.

    2015-10-01

    The isotopic-geochronological features of thorianite and baddeleyite from carbonatites of the Guli massif, located within Maimecha-Kotui province in the north of the Siberian Platform, are characterized for the first time. The economic complex platinum-group element (PGE) and gold placer deposits are closely related to the Guli massif. Similar geochronological data for thorianite (250.1 2.9 Ma, MSWD = 0.09, n = 36) and baddeleyite (250.8 1.2 Ma, MSWD = 0.2, n = 6) obtained by two different methods indicate that carbonatites were formed close to the Permian-Triassic boundary and are synchronous with tholeiitic flood basalts of the Siberian Platform.

  7. dme vulvaire massif pendant la grossesse: propos d'un cas

    PubMed Central

    El Hassani, Moulay Elmehdi; Kassidi, Farid; Benabdejlil, Youssef; Kouach, Jaouad; Moussaoui, Driss Rahali; Dehayni, Mohammed

    2014-01-01

    Ldme vulvaire massif est rare pendant la grossesse, mais requiert une attention particulire car il peut se greffer de complications maternelles et ftales. Il peut tre associ plusieurs pathologies spcifiques ou non spcifiques la grossesse dont le diagnostic fait appel obligatoirement un interrogatoire et un examen clinique minutieux, puis un bilan biologique standard. Le traitement doit tre tiologique chaque fois que possible cot du traitement symptomatique. Cette situation peut ncessiter un accouchement par csarienne. En dehors du risque potentiel de ncrose tissulaire et du risque exceptionnel de dcs maternel associ ldme vulvaire massif du post-partum lvolution est favorable sous traitement bien conduit. PMID:25922627

  8. A Subnational Perspective for Comparative Research: Education and Development in Northeast Brazil and Northeast Thailand.

    ERIC Educational Resources Information Center

    Fry, Gerald; Kempner, Ken

    1996-01-01

    Case studies of northeast Brazil and northeast Thailand highlight the importance of a subnational approach to comparative research. Compares geographic and economic conditions, regional culture, ethnicity and gender issues, migration patterns, religion, literacy, and educational underdevelopment. Points out that neglect of a region and its people

  9. Timing and Style of Deformation in the Floresta Massif, Axial Eastern Cordillera, Colombia

    NASA Astrophysics Data System (ADS)

    Saylor, J.; Stockli, D. F.; Mora, A.

    2009-12-01

    The Floresta Massif is one of the largest exposures of Paleozoic and Pre-Cambrian rocks in the Eastern Cordillera. Estimates for the age of onset of shortening-related deformation in the Eastern Cordillera range from late Cretaceous to late Miocene (e.g., Hoorn et al., 1995; Bayona et al., 2008; Parra et al., 2009). The massif is typically interpreted as being exhumed along a high-angle reverse fault (the Soapaga fault) that reactivated Mesozoic extensional structures (e.g., Kammer and Sanchez, 2006). We examined these dual linked issued with new zircon U/Th-He (ZHe) data, new geological mapping and previously published apatite fission track (AFT) data from the Floresta Massif and the associated footwall strata. Previously, an overturned Paleozoic - Cretaceous sequence was mapped emplaced on Tertiary strata along the Soapaga fault. However, new geologic mapping identifies two previously unrecognized thrusts which place, from west to east, Paleozoic strata on Jurassic strata (Fault 3), Jurassic strata on Cretaceous strata (Fault 2) and Cretaceous strata on Tertiary strata (along the previously identified Fault 1). These results are confirmed by AFT and ZHe data. ZHe ages show no resetting in the Tertiary footwall strata, but show partial resetting in the Cretaceous strata and full resetting in the Jurassic and Paleozoic strata. Similarly, AFT data show older ages in the Cretaceous strata than in the Jurassic or Paleozoic strata. Fully reset ZHe ages from Jurassic strata show that exhumation of the Floresta Massif was ongoing by at least the early Oligocene (~ 30 Ma). However, this deformation post-dates an older episode of deformation associated with partially reset ZHe ages in the Cretaceous strata. Based on a decrease in lag time in detrital ZHe data, we infer that the earlier episode of deformation occurred in the mid - late Eocene (45 - 35 Ma).

  10. Mineralogy and geochemistry of the Tartai massif, East Siberian metallogenic province

    NASA Astrophysics Data System (ADS)

    Podlipsky, M. Yu.; Mekhonoshin, A. S.; Tolstykh, N. D.; Vishnevskiy, A. V.; Polyakov, G. V.

    2015-05-01

    The Tartai ultramafic-mafic massif is located in the central part of the East Siberian metallogenic (PGE-Cu-Ni) province (728-712 Ma), which constitutes part of the southern margin of the Siberian craton. This dunite-peridotite-pyroxenite-gabbro massif is the host to low-sulfide PGE-Cu-Ni mineralization. The massif was formed by fractional crystallization of picritic magmas and is composed of wehrlite, dunite, plagiowehrlite, and olivine melanogabbro. The composition of olivine varies from Fo89.9 in dunite to Fo83 in melanocratic olivine gabbro; clinopyroxene is esentially augite. Chrome-spinels crystallized at a low degree of oxidation and have a high iron content. Disseminated sulfide mineralization (pentlandite and heazlewoodite) with high PGE concentrations was identified in wehrlites. Pentlandite is enriched in Fe and Co and depleted in S. These features and the association pentlandite with heazlewoodite suggest that the sulfide mineralization was formed over a wide temperature range (600-400C) at low sulfur activity (log fS2 from -16 to -9). PGM are represented by Ir-bearing sperrylite, Pd-Cu-Sb panning compounds of variable compositions, Pt-Fe-Cu and Pt-Cu alloys. The evolutionary trend of the ore system was from essentially Ni compositions at the early magmatic stage during formation of disseminated mineralization toward Cu-rich composition at the post-magmatic stage. The PGM assemblage from heavy concentrate haloes differs from bedrock-hosted mineralization in its wider variety of mineral species and the presence of refractory platinoids. Sperrylite from heavy concentrate haloes of the Tartai massif serves as a reliable prospecting guide for bedrock-hosted sulfide Cu-Ni deposits.

  11. U Pb dating of high temperature metamorphic episodes in the Kon Tum Massif (Vietnam)

    NASA Astrophysics Data System (ADS)

    Roger, Franoise; Maluski, Henri; Leyreloup, Andr; Lepvrier, Claude; Truong Thi, Phan

    2007-05-01

    In Vietnam, recent studies demonstrated that the Kon Tum Massif was part of the Indosinian mountain system, together with the Truong Son Belt. One sector of the Kon Tum Massif (Song Ba valley) is a granulite facies terrain for which Ar-Ar and U-Pb ages cluster around 245-250 Ma. In the area of Song Bien river, also metamorphosed under granulite facies conditions, Ar-Ar ages of 410 Ma are displayed by biotite. In this study, U-Pb dating of monazite and zircon has been used to understand the reason for these two groups of ages, taking into account the metamorphic mineral assemblages related to granulite facies metamorphism in the two districts. For granulites of Song Ba valley, ages of 245-250 Ma are confirmed from monazites. In the Song Bien district, ages of 465-470 Ma displayed by monazites are interpreted to correspond to the metamorphic climax. Zircons from one of these samples record the age of anatexis that has affected the granulitic rocks. The younger age recorded in the Song Ba valley is considered to reflect high temperature related to charnockitic intrusions emplaced near the end of the Indosinian orogeny, overprinting the earlier formed granulites and resetting the U-Pb and Ar-Ar ages. For the first time, two HT events are dated in the Kon Tum Massif, one occurring during the Ordovician and the other during the Permo-Triassic.

  12. First SHRIMP U Pb zircon dating of granulites from the Kontum massif (Vietnam) and tectonothermal implications

    NASA Astrophysics Data System (ADS)

    Nam, Tran Ngoc; Sano, Yuji; Terada, Kentaro; Toriumi, Mitsuhiro; Van Quynh, Phan; Dung, Le Tien

    2001-02-01

    The Kontum massif in Central Vietnam represents the largest continuous exposure of crystalline basement of the Indochina craton. The central Kontum massif is chiefly made of orthopyroxene granulites (enderbite, charnockite) and associated rocks of the Kannack complex. Mineral assemblages and geothermobarometric studies have shown that the Kannack complex has severely metamorphosed under granulite facies corresponding to P-T conditions of 800-850C and 81 kbars. Twenty-three SHRIMP II U-Pb analyses of eighteen zircon grains separated from a granulite sample of the Kannack complex yield ca 254 Ma, and one analysis gives ca 1400 Ma concordant age for a zoned zircon core. This result shows that granulites of the Kannack complex in the Kontum massif have formed from a high-grade granulite facies tectonothermal event of Indosinian age (Triassic). The cooling history and subsequent exhumation of the Kannack complex during Indosinian times ranged from 850C at ca 254 Ma to 300C at 242 Ma, with an average cooling rate of 45C/Ma.

  13. Geochemical specialization of the tin-bearing granitoid massifs of NW Bohemia

    NASA Astrophysics Data System (ADS)

    Breiter, K.; Sokolov, M.; Sokol, A.

    1991-10-01

    The geochemistry of Hercynian tin-bearing granitoid massifs of the Krune hory Mts. (Erzgebirge), Slavkovsk les Forest (Kaiserwald) and Smr?iny (eastern Fichtelgebirge) is compared by statistical processing of 270 analyses including a wide spectrum of major and trace elements. Seven different types of granites are distinguished. Out of these, five types represent the successive differentiation of the largest massif of NW Bohemia: the Karlovy Vary (Karlsbad) massif. This comprises strongly differentiated peraluminous granites evolving towards extreme Li-Rb-Cs-F-and Sn-enrichment in the youngest members, which are albite-topaz-zinwaldite lithium granites. The sixth and seventh types are different from the former by their location in the eastern Krune hory and tectonic setting, and they display geochemical features of anorogenic granites: they are metaluminous albite-zinwaldite granites with marked enrichment of Nb, Y, and HREE in addition to Li, Rb, Cs, F and Sn, indicating contamination by sub-crustal material. Sn-W mineralizations, including flat peri-contact greisen bodies, steep greisen veins and tourmalinized phyllites, are all intimately associated with the most strongly differentiated granites the Li-granite and the Cinovec-granite respectively.

  14. Origin and significance of tourmalinites and tourmaline-bearing rocks of Menderes Massif, western Anatolia, Turkey

    NASA Astrophysics Data System (ADS)

    Yücel-Öztürk, Yeşim; Helvacı, Cahit; Palmer, Martin R.; Ersoy, E. Yalçın; Freslon, Nicolas

    2015-03-01

    In the western central portion of Anatolia lies the Menderes Massif - a large metamorphic crystalline complex made of Neoproterozoic to Precambrian basement rocks overlain by Palaeozoic to early Tertiary metasedimentary rocks, and with a multistage metamorphic evolution developed from the late Neo-Proterozoic to Eocene. We have undertaken a study of the petrology, geochemistry and boron isotope composition of these tourmaline occurrences aiming to constrain the processes responsible for the enrichment of boron and other fluid mobile elements in the Menderes Massif. The dispersed tourmaline has chemical and boron isotope compositions typical of a continental crust setting, but while some of the tourmalinites display similar signatures, others have heavier boron isotope compositions (up to + 7.5‰). We suggest that the tourmalinites with continental characteristics formed part of the original Pan African basement rocks, whereas those with heavier δ11B signatures formed by later metamorphism during the Alpine orogeny, possibly through interaction with subduction-like fluids. This proposed process may also have been coincident with metasomatism of the lithospheric mantle beneath the massif, which is known to have experienced multistage metasomatism and enrichment history up to Neogene time.

  15. Re-Os isotopic evidence for a lower crustal origin of massif-type anorthosites

    PubMed

    Schiellerup; Lambert; Prestvik; Robins; McBride; Larsen

    2000-06-15

    Massif-type anorthosites are large igneous complexes of Proterozoic age. They are almost monomineralic, representing vast accumulations of plagioclase with subordinate pyroxene or olivine and Fe-Ti oxides--the 930-Myr-old Rogaland anorthosite province in southwest Norway represents one of the youngest known expressions of such magmatism. The source of the magma and geodynamic setting of massif-type anorthosites remain long-standing controversies in Precambrian geology, with no consensus existing as to the nature of the parental magmas or whether these magmas primarily originate in the Earth's mantle or crust. At present, massif-type anorthosites are believed to have crystallized from either crustally contaminated mantle-derived melts that have fractionated olivine and pyroxenes at depth or primary aluminous gabbroic to jotunitic melts derived from the lower continental crust. Here we report rhenium and osmium isotopic data from the Rogaland anorthosite province that strongly support a lower crustal source for the parental magmas. There is no evidence of significantly older crust in southwest Scandinavia and models invoking crustal contamination of mantle-derived magmas fail to account for the isotopic data from the Rogaland province. Initial osmium and neodymium isotopic values testify to the melting of mafic source rocks in the lower crust with an age of 1,400-1,550 Myr. PMID:10866196

  16. Geodynamic movements and deformations of the Sudetic structural unit of the Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Schenk, V.; Jechumtlov, Z.; Schenkov, Z.; Kottnauer, P.

    2003-04-01

    The African plate pushes to European orogenic Alpine structures that transfer the compression further to Variscan structural units, including the Bohemian Massif. Central parts of the Bohemian Massif are relatively deep-seated and, therefore, some of marginal parts of the Massif and its border geological structures should be affected intensively and moved distinctly with respect to the central parts. The geodynamical GPS network EAST SUDETEN is located just over the area mentioned above, i.e. it covers both kinetically quasi-effected and quasi-non-effected structural blocks. GPS data observed already for six annual campaigns (1997-2002) were processed and movement vectors of individual network sites were assessed. Applied data processing did not allow errors in the horizontal direction 2 mm and in the vertical direction 5-6 mm to be exceeded. Since time series of coordinate changes for several network sites gave rather pronounce movement trends, preliminary deformations among individual structural blocks were evaluated and compared to other geological, geophysical and geodetic materials. The investigation has been supported by the Grant Agency of the Czech Republic, projects 205/97/0679 and 205/01/0480, and by the research programme of the Ministry of Education, Youth and Sport of the Czech Republic, project LN00A005 "Dynamics of the Earth".

  17. Age and sources of Precambrian zircon-rutile deposits in the Kokchetav sialic massif (northern Kazakhstan)

    NASA Astrophysics Data System (ADS)

    Degtyarev, K. E.; Kovach, V. P.; Tret'yakov, A. A.; Kotov, A. B.; Wang, Kuo-Lun

    2015-10-01

    The U-Pb geochronological data on detrital zircons from placers confined to Neoproterozoic quartzite-schist sequences, which are widespread in the Kokchetav massif of northern Kazakhstan, are discussed. Detrital zircons (332 grains in total) originate from the ore occurrences in the central, northern, and western parts of the massif. The concordant ages of detrital zircons from all the examined occurrences largely correspond to intervals of 1017-1528, 1628-1946, and 2653-2739 Ma. The obtained data imply that material of quartzite-schist sequences of the Kokchetav massif was provided by Mesoproterozoic, Paleoproterozoic, and Neoarchean rock complexes. The lower age limit determined for these sequences is approximately 1.06 Ga. The dates obtained for detrital zircons are most consistent with events that took place in Laurentia. They correspond to the formation and breakup of the Columbia/Nuna supercontinent (approximately 1650-1580 and 1450-1380 Ma ago, respectively) and formation of the Rodinia supercontinent in the period of 1300-900 Ma ago.

  18. Mapping of the Ronda peridotite massif (Spain) from AVIRIS spectro-imaging survey: A first attempt

    NASA Technical Reports Server (NTRS)

    Pinet, P. C.; Chabrillat, S.; Ceuleneer, G.

    1993-01-01

    In both AVIRIS and ISM data, through the use of mixing models, geological boundaries of the Ronda massif are identified with respect to the surrounding rocks. We can also yield first-order vegetation maps. ISM and AVIRIS instruments give consistent results. On the basis of endmember fraction images, it is then possible to discard areas highly vegetated or not belonging to the peridotite massif. Within the remaining part of the mosaic, spectro-mixing analysis reveals spectral variations in the peridotite massif between the well-exposed areas. Spatially organized units are depicted, related to differences in the relative depth of the absorption band at 1 micron, and it may be due to a different pyroxene content. At this stage, it is worth noting that, although mineralogical variations observed in the rocks are at a sub-pixel scale for the airborne analysis, we see an emerging spatial pattern in the distribution of spectral variations across the massif which might be prevailingly related to mineralogy. Although it is known from fieldwork that the Ronda peridotite massif exhibits mineralogical variations at local scale in the content of pyroxene, and at regional scale in different mineral facies, ranging from garnet-, to spinel- to plagioclase-lherzolites, no attempt has been done yet to produce a synoptic map relating the two scales of analysis. The present work is a first attempt to reach this objective, though a lot more work is still required. In particular, for the purpose of mineralogical interpretation, it is critical to relate the airborne observation to field work and laboratory spectra of Ronda rocks already obtained, with the use of image endmembers and associated reference endmembers. Also, the pretty rough linear mixing model used here is taken as a 'black-box' process which does not necessarily apply correctly to the physical situation at the sub-pixel level. One may think of using the ground-truth observations bearing on the sub-pixel statistical characteristics (texture, structural pattern, surface distribution and vegetation contribution (grass,..)) to produce a more advanced mixing model, physically appropriate to the geologic and environmental contexts.

  19. Jurassic hot spring deposits of the Deseado Massif (Patagonia, Argentina): Characteristics and controls on regional distribution

    NASA Astrophysics Data System (ADS)

    Guido, Diego M.; Campbell, Kathleen A.

    2011-06-01

    The Deseado Massif, Santa Cruz Province, Argentinean Patagonia, hosts numerous Middle to Late Jurassic age geothermal and epithermal features represented by siliceous and calcareous chemical precipitates from hot springs (sinters and travertines, respectively), hydrothermal breccias, quartz veins, and widespread hydrothermal silicification. They indicate pauses in explosive volcanic activity, marking the final stages in the evolution of an extensive Jurassic (ca. 178-151 Ma) volcanic complex set in a diffuse extensional back-arc setting heralding the opening of the Atlantic Ocean. Published paleo-hot spring sites for the Deseado Massif, plus additional sites identified during our recent field studies, reveal a total of 23 locations, five of which were studied in detail to determine their geologic and facies associations. They show structural, lithologic, textural and biotic similarities with Miocene to Recent hot spring systems from the Taupo and Coromandel volcanic zones, New Zealand, as well as with modern examples from Yellowstone National Park, U.S.A. These comparisons aid in the definition of facies assemblages for Deseado Massif deposits - proximal, middle apron and distal siliceous sinter and travertine terraces and mounds, with preservation of many types of stromatolitic fabrics - that likely were controlled by formation temperature, pH, hydrodynamics and fluid compositions. Locally the mapped hot spring deposits largely occur in association with reworked volcaniclastic lacustrine and/or fluvial sediments, silicic to intermediate lava domes, and hydrothermal mineralization, all of which are related to local and regional structural lineaments. Moreover, the numerous geothermal and significant epithermal (those with published minable resources) deposits of the Deseado Massif geological province mostly occur in four regional NNW and WNW hydrothermal-structural belts (Northwestern, Northern, Central, and Southern), defined here by alignment of five or more hot spring deposits and confirmed as structurally controlled by aeromagnetic data. The Northern and Northwestern belts, in particular, concentrate most of the geothermal and epithermal occurrences. Hence, Jurassic hydrothermal fluid flow was strongly influenced by the most dominant and long-active geological boundaries in the region, the outer limits of the Deseado Massif 'horst' itself.

  20. Garzon Massif basement tectonics: A geopyhysical study, Upper Magdalena Valley, Colombia

    NASA Astrophysics Data System (ADS)

    Bakioglu, Kadir Baris

    The mechanics and kinematics of basement tectonic uplifts, such as the Laramide Rocky Mountain orogeny, remain poorly understood and controversial. The debate continues in part because of the limited number of well-documented present day analogs. The Garzon Massif rising between the Upper Magdalena Valley and the Llanos Basin of Colombia is an active basement uplift with well, seismic, gravity, and magnetic data available. In the past 10 Ma, PreCambrian age granitic rocks of the Garzon Massif have been uplifted and displaced against Cretaceous and Tertiary sediments of the Upper Magdalena Valley along the Garzon fault. Aerogravimetric data calibrated by well data and 2D seismic data were used to model the geometry of the Garzon fault and the top of basement (Saldana Fm) in 2 dimensions. The density models provide an independent estimate of fault orientation. A high density airborne gravity and magnetic survey were flown over the Garzon fault in 2000, including 2,663 line km along 1 x 5 and 1 x 4 km flight lines at elevations of 2564 and 4589 m above mean sea level. An initial depth model was derived from the well logs, seismic reflection profile, and down-hole velocity surveys. Airborne gravity data was used to produce a Bouguer anomaly gravity map. Average rock densities were estimated from density logs, seismic velocities, and formation rock types. The regional gravity field was estimated and 2-dimensional forward models were constructed with average densities from the wells, seismic velocities, and rock types, and the initial depth model. Since the model fit is dependent on the density assumed for the Garzon Massif rocks, multiple densities and dip angles were tested. The gravity analysis indicates that the Garzon fault is a basement thrust fault dipping at a shallow angle under the Massif. Best-fit models show a true dip of 12 to 17 degrees to the southeast. A regional density and magnetic susceptibility model of the entire Massif is consistent with dense basement rocks throughout the Garzon Massif and asymmetric loading (sedimentary basin is much deeper on NW flank -- Upper Magdalena Valley). Crust thickens to the NW toward the Central Cordillera. Euler deconvolution of the magnetic field shows pronounced NE-SW trending features under the Massif which are interpreted as faults bounding a possible pre-Cambrian sedimentary rift graben. Retrodeformed 2D regional models indicate 13 km of shortening on the Garzon basement thrust in the last 12 Ma. Approximately 9 km of shortening occurred on the SE marginal basement thrust fault, probably also in the last 12 Ma. This was preceded by approximately 43 km of shortening by thin-skinned imbricate thrusting to the southeast (12 - 25 Ma). This study provides a well-documented example of an active basement uplift on low angle thrust faults.

  1. Neogene Uplift and Exhumation of Plutonic Bodies in the Beni Bou Ifrour Massif (Nador, northeastern Morocco)

    NASA Astrophysics Data System (ADS)

    Lebret, Nomie; Jolivet, Laurent; Branquet, Yannick; Bourdier, Jean-Louis; Jolivet, Marc; Marcoux, Eric

    2013-04-01

    In Neogene times, the whole Mediterranean Sea was the center of an intense magmatic activity. This post-collisional magmatism produced a large amount of volcanic edifices through the Alpine belts, together with some intrusives. These plutonic bodies can be associated with skarn-type mineralization, well-known in Elba Island or Serifos Island (Cyclades), where they are generally exhumed by detachment faults. In Morocco, the plutons hosted by the Beni Bou Ifrour massif are connected to the biggest skarn-type iron concentrations of the country (production > 60 Mt, reserves ? 25 Mt). The purpose of this work is to explain the late uplift of this massif and subsequent exhumation of the intrusives. As a final product of the Africa-Eurasia plate convergence since ca. 70 Ma, the Rif Mountains constitute the westernmost segment of the Mediterranean Alpine belts. In the oriental part of this range, volcanic summits and Paleozoic to Mesozoic massifs outcrop in the surrounding Mio-Pliocene plains. The Beni Bou Ifrour massif, in the Nador province, consists in a dome-shaped folded Mesozoic series (Domerian to Barremian) affected by a slight epizonal regional metamorphism (ca. 14-12 Ma), dislocated by Neogene NE-SW faults and eventually sealed by upper Miocene transgressive sediments. The hosted intrusives (7.58 0.03 Ma; Duggen et al., 2005) are the plutonic equivalents to the potassic calc-alkaline lavas (andesites mainly) from the surrounding "satellite" volcanic massifs. They turn out to stand in higher topographic position than the younger shoshonitic lavas of the neighboring Gourougou stratovolcano (6.12 0.01 Ma; Duggen et al., 2005). Previous studies have attributed this uplift to the action of normal faults (pull-apart basins; Guillemin & Houzay, 1982), thrusting (Kerchaoui, 1985; 1995) or even of a caldeira resurgence (El Bakkali, 1995). To discriminate against those exhumation mechanisms, field work has been performed, coming along with new cross-sections to illustrate the geometry of the Beni Bou Ifrour massif. A paleomagnetism campaign was conducted, to determine if the plutonic intrusions have been tilted since their emplacement. Apatite fission tracks and 40Ar-39Ar dating allow us to estimate the exhumation age of the igneous bodies, and therefore add chronological constraints to the tectonic model. Geochemical study has also been performed on the magmatic rocks, and added to an extensive dataset (El Bakkali, 1995; Kerchaoui, 1995; Duggen et al., 2005). The existence of a magmatic chamber below the Beni Bou Ifrour dome will thus be discussed. Once established, the tectonic model of the Beni Bou Ifrour massif will help to precise the emplacement of the mineralized bodies and to integrate the iron-skarn metallogenesis within the structural evolution of the Rif orogenic segment.

  2. Interior view of northeast unit master bedroom, looking into sleeping ...

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

    Interior view of northeast unit master bedroom, looking into sleeping porch, facing northeast - MacDill Air Force Base, Double Non-Commissioned Officers' Quarters, 7418 Hanger Loop Drive, Tampa, Hillsborough County, FL

  3. 39. FOURTH FLOOR: DETAIL OF STEAM HEATING PIPES ON NORTHEAST ...

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

    39. FOURTH FLOOR: DETAIL OF STEAM HEATING PIPES ON NORTHEAST WALL OF DINING AND SOCIAL HALL ON NORTHWEST END OF BUILDING LOOKING NORTHEAST - Masonic Temple, 1111-1119 Eleventh Street, Altoona, Blair County, PA

  4. 19. GENERAL VIEW, LOOKING SOUTHWEST TO NORTHEAST, SHOWING ENCLOSED OFFICE ...

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

    19. GENERAL VIEW, LOOKING SOUTHWEST TO NORTHEAST, SHOWING ENCLOSED OFFICE UNITS FLANKING OVERHEAD PORT AT NORTHEAST END OF BUILDING - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  5. 7. Oil house, view northeast, west and south sides ...

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

    7. Oil house, view northeast, west and south sides - Great Duck Island Light Station, At southern tip of Great Duck Island southeast of Bass Harbor & northeast of Frenchboro, Frenchboro, Hancock County, ME

  6. 3. Light tower and fog signal house, view northeast, west ...

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

    3. Light tower and fog signal house, view northeast, west and south sides - Great Duck Island Light Station, At southern tip of Great Duck Island southeast of Bass Harbor & northeast of Frenchboro, Frenchboro, Hancock County, ME

  7. 27. NORTHEAST ROOM ORIGINALLY CLASSROOM NO. 1, LAST USED ...

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

    27. NORTHEAST ROOM - ORIGINALLY CLASSROOM NO. 1, LAST USED AS A LOCKER ROOM. SECOND FLOOR - OFFICE. VIEW TO NORTHEAST. - Milwaukee Light, Heat & Traction Company, 8336 West Lapham Street, West Allis, Milwaukee County, WI

  8. 1. BUILDING 522, SOUTH SIDE, OBLIQUE VIEW, FROM NORTHEAST CORNER ...

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

    1. BUILDING 522, SOUTH SIDE, OBLIQUE VIEW, FROM NORTHEAST CORNER OF BUILDING 431, LOOKING NORTHEAST. - Oakland Naval Supply Center, Aeronautical Materials Storehouses, Between E & G Streets, between Fourth & Sixth Streets, Oakland, Alameda County, CA

  9. 20. DETAIL OF OFFICE FURNITURE IN NORTHEAST CORNER OF SECRETARIES' ...

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

    20. DETAIL OF OFFICE FURNITURE IN NORTHEAST CORNER OF SECRETARIES' OFFICE ALONG NORTH SIDE OF FIRST FLOOR. VIEW TO NORTHEAST. - Boise Project, Boise Project Office, 214 Broadway, Boise, Ada County, ID

  10. CLOVER CREEK BRIDGE, SOUTH ELEVATION DETAIL, FACING NORTH NORTHEAST ...

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

    CLOVER CREEK BRIDGE, SOUTH ELEVATION DETAIL, FACING NORTH NORTHEAST - Generals Highway, Clover Creek Bridge, Spanning Clover Creek on Generals Highway, approximately 22 miles northeast of Ash Mountain Entrance, Three Rivers, Tulare County, CA

  11. 19. INTERIOR OF NORTHEAST REAR BEDROOM SHOWING ALUMINUMFRAME SLIDING GLASS ...

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

    19. INTERIOR OF NORTHEAST REAR BEDROOM SHOWING ALUMINUM-FRAME SLIDING GLASS WINDOWS. VIEW TO NORTHEAST. - Bishop Creek Hydroelectric System, Plant 4, Worker Cottage, Bishop Creek, Bishop, Inyo County, CA

  12. 34. NORTHEAST CORNER OF GALLERY IN MAIN MEETING ROOM LOOKING ...

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

    34. NORTHEAST CORNER OF GALLERY IN MAIN MEETING ROOM LOOKING NORTHEAST. Looking down from the 1936 raised gallery level to the old gallery level. - Twelfth Street Meeting House, 20 South Twelfth Street, Philadelphia, Philadelphia County, PA

  13. 2. General context view of Express Building, looking northeast, with ...

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

    2. General context view of Express Building, looking northeast, with Division Street in foreground, showing relationship to the Bend Depot - American Railway Express Company Freight Building, 1060 Northeast Division Street, Bend, Deschutes County, OR

  14. 1. HEBRONVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR. HEBRONVILLE, BRISTOL ...

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

    1. HEBRONVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR. HEBRONVILLE, BRISTOL CO., MA. Sec. 4116, MP 193.75. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

  15. 3. DODGEVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR DODGEVILLE, BRISTOL ...

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

    3. DODGEVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR DODGEVILLE, BRISTOL CO., MA. Sec. 4116, MP 195.55. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

  16. Steam sand dryer in northeast part of sand tower. View ...

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

    Steam sand dryer in northeast part of sand tower. View to northeast - Duluth & Iron Range Rail Road Company Shops, Sand Tower, Southwest of downtown Two Harbors, northwest of Agate Bay, Two Harbors, Lake County, MN

  17. OVERALL VIEW OF QUARRY, FACING NORTHEAST, SHOWING SOUTHERN SECTION OF ...

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

    OVERALL VIEW OF QUARRY, FACING NORTHEAST, SHOWING SOUTHERN SECTION OF QUARRY - Granite Hill Plantation, Quarry No. 2, South side of State Route 16, 1.3 miles northeast east of Sparta, Sparta, Hancock County, GA

  18. 55. VIEW TO NORTHEAST OF MOTOR AND REDUCTION GEAR NO. ...

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

    55. VIEW TO NORTHEAST OF MOTOR AND REDUCTION GEAR NO. 1: View towards the northeast of Motor and Reduction Gear No. 1, installed in 1957. - San Francisco Cable Railway, Washington & Mason Streets, San Francisco, San Francisco County, CA

  19. 2. Light tower and keeper's house, view southwest, north northeast ...

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

    2. Light tower and keeper's house, view southwest, north northeast side of tower, northeast and northwest sides of keeper's house - Wood Island Light Station, East end of Wood Island, at mouth of Soo River, Biddeford Pool, York County, ME

  20. 11. DETAIL SHOWING ROLLING ENGINE DECK AND NORTHEAST TRUSS OF ...

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

    11. DETAIL SHOWING ROLLING ENGINE DECK AND NORTHEAST TRUSS OF SUPERSTRUCTURE. Looking northeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  1. 10. Lighthouse boathouse and granite wharf, view north northeast, southwest ...

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

    10. Lighthouse boathouse and granite wharf, view north northeast, southwest and southeast sides of boathouse, west and south sides of dock - Whitehead Light Station, Whitehead Island, East northeast of Tenants Harbor, Spruce Head, Knox County, ME

  2. Late variscan exhumation processes in the Tanneron massif (SE France) deduced from structural and 40Ar-39Ar analyses

    NASA Astrophysics Data System (ADS)

    Bosse, V.; Corsini, M.; Ferraud, G.

    2003-04-01

    Detailed 39Ar-40Ar measurements were performed in the Maures and Tanneron massifs (separated by a Permian basin) that belong to the southernmost segment of the French Variscan belt. By analyzing amphibole, muscovite and biotite from the Maures massif, Morillon and al.(2000) evidenced two crustal blocks with distinct cooling path between 330 and 300 Ma. These authors underlined the role of a major ductile strike-slip fault, which separate the two blocks during the exhumation process. In the Tanneron massif, plateau ages ranging from 302 +/-2 to 321 +/-2 Ma were displayed by single grains of muscovite from metamorphic and magmatic rocks. The age distribution throughout the massif reflects an inhomogeneous cooling of rocks around 350C, which is not geometrically correlated with those obtained in the two blocks of the Maures Massif. Three different domains are evidenced: (i) in the Western Tanneron, ages range from 307 +/-2 to 314 +/- 2 Ma, (ii) in the Central Tanneron, ages range from 317 +/- 2 to 321 +/- 2 Ma and (iii) in the Eastern Tanneron, ages range from 314 +/- 1 to 315 +/- 2 Ma. The youngest ages of 303 +/- 2 and 303 +/- 2 Ma were obtained on intrusives crosscutting the metamorphic foliation in the Western Tanneron; the latter are concordant with late granitic intrusions and opening of intra-continental Stephanian basins. Two hypotheses may be proposed to interpret this inhomogeneous cooling between 320 and 300 Ma: (i) the presence of tectonic blocks limited by ductile shear zones with differential motion (as previously suggested for the Maures massif) or (ii) a thermal structure related to tectonic doming and plutonic intrusions. Both processes could act simultaneously. These results better constrain the assumed extension of the tectonic contacts between the two massifs under the Bas Argens Permian basin. The late Variscan evolution of the Tanneron and Maures massifs revealed by this detailed geochronological study is similar to the French Central Massif, where post-collisional exhumation processes during late Carboniferous imply doming associated either with crustal-scale ductile strike-slip faults or with normal faults.

  3. Biodiversity impact of the aeolian periglacial geomorphologic evolution of the Fontainebleau Massif (France)

    NASA Astrophysics Data System (ADS)

    Thiry, M.; Liron, M. N.

    2009-04-01

    Landscape features The geomorphology of the Fontainebleau Massif is noteworthy for its spectacular narrow ridges, up to 10 km long and 0.5 km wide, armored by tightly cemented sandstone lenses and which overhang sandy depressions of about 50m. Denudation of the sandstone pans lead to a highly contrasted landscape, with sandstone ridges ("platières") towering sandy depressions ("vallées") and limestone plateaus ("monts"). This forms the geological frame of the spectacular sceneries of the Fontainebleau Massif (Thiry & Liron, 2007). Nevertheless, there is little know about the erosive processes that have built-up these landscapes. Periglacial processes, and among them aeolian ones, appear significant in the development of the Fontainebleau Massif physiography. The periglacial aeolian geomorphology Dunes and dune fields are known since long and cover about 15% to 25% of the Fontainebleau Massif. The aeolian dunes developed as well on the higher parts of the landscape, as well as in the lower parts of the landscape. The dunes are especially well developed in the whole eastern part of the massif, whereas the western part of the massif is almost devoid of dunes. Nevertheless, detailed mapping shows that dunes can locally be found in the western district, they are of limited extension, restricted to the east facing backslope of outliers. Loamy-sand covers the limestone plateaus of the "monts". The loam cover is of variable thickness: schematically thicker in the central part of the plateaus, where it my reach 3 m; elsewhere it may thin down to 0,20-0,30 m, especially at the plateau edges. Blowout hollows are "negative" morphologies from where the sand has been withdrawed. Often these blowouts are decametric sized and well-delimited structures. Others, more complex structures, are made up of several elongated hectometric hollows relaying each other from and which outline deflation corridor more than 1 km long. A characteristic feature of these blowout hollows is the erosion of the sand beneath the bordering sandstone benches, resulting in overhangs. These structures are the most common in the western district of the Fontainebleau Massif. Ponds develop on the tightly silicified and impermeable sandstone pans that form the "platières". There are permanent ponds and temporary wet zones, formed of interconnected or isolated depressions. The origin of these ponds has to be questioned with regard to the landscape shaping. Their origin is directly bound to the hollowing of uncemented, sandy zones, within the sandstone pans forming the "platières". Erosion by runoff cannot be considered; the only way to hollow them out is by deflation processes. No direct dating of the Quaternary dune and loess deposits of the Fontainebleau Massif exists. Nevertheless, dating of paleopodzols interlayered between drift sands, pond deposits and bones within congelifracts allow relating these periglacial features with the end of the last glacial period. For now, there is no dating to assess what belongs to older glacial periods. Distribution of the aeolian patterns The Fontainebleau Massif displays noteworthy morphological diversities in the various districts of the forest. Some of these differentiations result from geological features, but most of them are related to erosion processes, and among them deflation processes leaved different imprints in the western and eastern districts of the Fontainebleau Massif. The topography played an important role controlling the aeolian processes. Deflation was important in the westerly upwind district. In the westerly front face, aeolian erosion was activated by turbulences around the topographic obstacles. The reliefs funneled the winds and gave rise to swirls that hollow the blowouts. This area displays the sharpest and more chiseled landforms of the massif. Moreover, the sandstone scarps at the edge of the "platières" are high and uncovered, with frequent overhangs. The collapsed sandstone blocks of the "chaos" are imposing, with blocks piling up and rising well off the sandy slopes. The sandstone "platières" are mostly bare as say above. Downwind, in the eastern district, the landforms are more subdued. The deflation is less extensive, the sandstone scarps and chaos are partly sanded up, with drift sand amassing at the lee side of the scarps. The "platières" have a sand cover that favours often the development of a tree stratum composed almost entirely of pine and birch trees. Aeolian landforms and biodiversity Despite the Atlantic climate forest cover and the human interventions, the imprints of the aeolian features inherited from the Quaternary periglacial climates still mark deeply the Fontainebleau landscapes. The aeolian actions command partly the present-day relief and vegetation biodiversity: (1) Tall oak and beech groves on the plateaus and in the lowlands covered with fine calcareous sand dunes and loess on which develop brown soils (prevailing in the eastern district of the massif); (2) Birch, pine trees and herbaceous stratum on the dry and acidic podzols established on the quartzose Fontainebleau Sand forming the windup scraps, sandstone chaos and associated dunes (dominant in the western district); (3) And finally dry moors with calluna, heather and birch on the sandstone "platières" stripped off by the aeolian deflation together with wet and peaty moors with sphagnum and moor-grass in the blowout depressions. The opposition between the western and the eastern districts of the massif was even more pronounced a few centuries ago, before man intervened vigorously to wooden the western area with massive import of pine trees. This phytogeographical diversity of the landscape is directly inherited from the periglacial aeolian actions and contributes to the striking biodiversity of the Fontainebleau Massif. The biological richness of the Fontainebleau Massif has been noticed as soon as 1664 (Barillon d'Amoncourt, 1664) and today have been inventoried 6.000 vegetable species among them 1350 flowering plants, some 460 mosses, about 500 algae, 675 lichens, 2.700 fungus, plus the insects, the birds, the mammals and batrachians (Testut et al., 1998). This exceptional biodiversity has been recognized in 1998 by the creation of a reserve of "Man and Biosphere" under the aegis of UNESCO. The "platières" landscapes are of special interest for biodiversity. The acidic soils on the sandstone "platières" are mainly covered by Atlantic moors. The dry moors with Calluna vulgaris and Erica cinerea relate to the Ulici-Ericion cinereae and the wet peaty moors are linked to the Ulici-Ericion tetralicis (Habitats 31.11 and 31.2 of the Corine Biotope Code). These dry and peaty moors interweave in a complex patchwork depending on the local, even metric scale, topography and soil moisture. The main interest in the flora of the "platières" lies in the vegetation of the network of pools, which develop in the sandstone depressions (Liron & Thiry, 2005). These wet zones include seven Natural Habitats of Community interest and nearly twenty protected plants species. The temporary ponds (Habitat 22.31 of the Corine Biotope Code), with an irregular hydraulic regime, favor a suite of annual plants, outstanding "intermittent" species, such as the endemic Franco-Iberian Ranunculus nodiflorus. In the acidic and oligotrophic waters of the permanent pools develop Utricularia australis along with Potamogeton polygonifolius. The peaty zones are valuable for their bryophyte biodiversity. For example thirteen species of Sphagnum (30 % of the European flora) have been recorded including Sphagnum magellanicum which is a rare species in the lowlands. There is also a wealth of bryophytes and lichens on the strata, with for instance fifty species of the lichen genus Cladonia. This species richness is strengthened by the limited area of the "platières" which represent only 15-20% of the whole massif. Main biodiversity interest is related to the almost bare "platières" of the western district eroded by deflation. The eastern platières that have a more continuous sand cover are support much less wet zones and only very few sites with protected plant species. Therefore, aeolian landscape evolution still triggers development and distribution of peculiar ecological sites. It suits to continue and to deepen the cartographic studies and the inventories to highlight these very particular landscapes of the Fontainebleau Massif and to protect them. Indeed, with 17 millions visitors per year, the problems are now mainly of managing natural areas, let them accessible, while protecting them. In the future, with forecasted climatic changes, a main concern will be how to preserve the biodiversity, knowing that the foresters manage generally the forest with a 150 years plan. Education and awareness campaign of the public and of the local actors of the sustainable development are essential, they require the knowledge of these fragile environments inherited from the past. References Barillon d'Amoncourt P., 1664-1665. Réformation générale de la forest de Bière et des autres bois dépendants de la maîtrise des Eaux et Forets du Baillage de Melun établie à Fontainebleau. Archives Départementales de Seine et Marne, France. Liron M.N., Thiry M., 2005, Peaty micro-zones on the sandstone ridges of the Fontainebleau Massif (France): hydrology and vegetation biodiversity. in : Ch. Ries & Y. Krippel (eds.), Sandstone landscapes in Europe. Past, Present and Future. Proceedings of the 2nd Intern. Conference on Sandstone Landscapes, Vianden (Luxembourg), 25-28 may 2005, Ferrantia, Luxembourg, 44, p. 215-220. Testut A., Hermeline M., Rey G., 1998. Lettres de la Forêt. Fontainebleau, abcédaire photographique. Textuel Ed., Paris, 223 p. Thiry M., Liron M.N., 2007, Fontainebleau Sandstones (France). In : Härtel H., Cílek V., Herben T., Jackson A. and Williams R. (eds.): Sandstone Landscapes.- Academia, Praha, p. 359-361.

  4. Amphibole genesis in pyroxenites from the Beni Bousera peridotite massif (Rif, Morocco): Evidence for two different metasomatic episodes

    NASA Astrophysics Data System (ADS)

    El Atrassi, Fatima; Chazot, Gilles; Brunet, Fabrice; Chopin, Christian; Bouybaouene, Mohamed

    2014-11-01

    The presence of variable amounts of amphibole phlogopite in a garnet websterite and a garnet clinopyroxenite from the Beni Bousera peridotite massif provides evidence for post-formation metasomatism. Textural observations associated with major- and trace-element mineral compositions allowed us to distinguish two metasomatic episodes, which occurred at different stages of the Beni Bousera massif evolution. The garnet websterite has recorded interaction with LREE-rich silicate melts before the uplift of the massif. Amphibole/clinopyroxene and amphibole/garnet trace-element ratios closely approach partition coefficient values, indicating that chemical equilibrium was attained between amphibole and pyroxenite matrix minerals. The geochemical signatures of the putative alkaline interacting melts are similar to those of recent basaltic magmas erupted in Morocco, suggesting a common peridotite mantle source. In contrast, amphibole from the garnet clinopyroxenite is in chemical disequilibrium with the pyroxenite matrix minerals. In this clinopyroxenite the crystallization of amphibole and plagioclase occurred at lower T (and P) conditions, most probably during the ascent of the Beni Bousera massif and its emplacement into the crust. The melt responsible for this later metasomatic episode was LREE-depleted and HREE-enriched, suggesting that it resulted from decompression melting of a garnet-bearing source (with garnet as a melting phase), similar to the garnet-bearing pyroxenites outcropping in the Beni Bousera massif.

  5. NORTHEAST VIEW OF FOUNDRY FROM TOP OF GREY IRON CUPOLA ...

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

    NORTHEAST VIEW OF FOUNDRY FROM TOP OF GREY IRON CUPOLA SHOWING CORE ROOM ROOF DIRECTLY NORTHEAST, GREY IRON FOUNDRY TO THE RIGHT, MALLEABLE IRON CUPOLAS AND FOUNDRY NORTHEAST OF GREY IRON FOUNDRY WITH THE BRASS FOUNDRY IN THE REAR. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  6. 76 FR 32391 - Northeast Corridor Safety Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-06

    ... Northeast Corridor, and the purpose of the Committee is to provide annual recommendations to the Secretary of Transportation. DATES: The meeting of the Northeast Corridor Safety Committee is scheduled to commence on Tuesday, June 14, 2011, at 9 a.m. and will adjourn by 3 p.m. ADDRESSES: The Northeast...

  7. PASTURE CONDITION SCORES IN THE NORTHEAST USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Assessment and monitoring tools are needed to determine the condition of grazing lands in the northeast. The Pasture Condition Score System has been developed by the NRCS for use as a monitoring and management tool on grazing lands. This system has not been evaluated systematically on a large scale ...

  8. Teacher Morale in Rural Northeast Tennessee

    ERIC Educational Resources Information Center

    Eggers, Brenda Dishman

    2012-01-01

    The purpose of this quantitative study was to investigate the factors that influence the morale levels of teachers in the public school systems of 3 contiguous counties in rural northeast Tennessee. The level of teacher morale was measured using the Purdue Teacher Opinionaire. Data associated with the Tennessee Value-Added Assessment System…

  9. Catalog of Apollo 17 rocks. Volume 1: Stations 2 and 3 (South Massif)

    NASA Technical Reports Server (NTRS)

    Ryder, Graham

    1993-01-01

    The Catalog of Apollo 17 Rocks is a set of volumes that characterize each of 334 individually numbered rock samples (79 larger than 100 g) in the Apollo 17 collection, showing what each sample is and what is known about it. Unconsolidated regolith samples are not included. The catalog is intended to be used by both researchers requiring sample allocations and a broad audience interested in Apollo 17 rocks. The volumes are arranged geographically, with separate volumes for the South Massif and Light Mantle, the North Massif, and two volumes for the mare plains. Within each volume, the samples are arranged in numerical order, closely corresponding with the sample collection stations. The present volume, for the South Massif and Light Mantle, describes the 55 individual rock fragments collected at Stations two, two-A, three, and LRV-five. Some were chipped from boulders, others collected as individual rocks, some by raking, and a few by picking from the soil in the processing laboratory. Information on sample collection, petrography, chemistry, stable and radiogenic isotopes, rock surface characteristics, physical properties, and curatorial processing is summarized and referenced as far as it is known up to early 1992. The intention has been to be comprehensive: to include all published studies of any kind that provide information on the sample, as well as some unpublished information. References which are primarily bulk interpretations of existing data or mere lists of samples are not generally included. Foreign language journals were not scrutinized, but little data appears to have been published only in such journals. We have attempted to be consistent in format across all of the volumes, and have used a common reference list that appears in all volumes. Where possible, ages based on Sr and Ar isotopes have been recalculated using the 'new' decay constants recommended by Steiger and Jager; however, in many of the reproduced diagrams the ages correspond with the 'old' decay constants. In this volume, mg' or Mg' = atomic Mg/(Mg +Fe).

  10. Significance of Geological Units of the Bohemian Massif, Czech Republic, as Seen by Ambient Noise Interferometry

    NASA Astrophysics Data System (ADS)

    Růžek, Bohuslav; Valentová, Lubica; Gallovič, František

    2015-10-01

    uc(A)bstract Broadband recordings of 88 seismic stations distributed in the Bohemian Massif, Czech Republic, and covering the time period of up to 12 years were processed by a cross-correlation technique. All correlograms were analyzed by a novel approach to get both group and phase dispersion of Rayleigh and Love waves. Individual dispersion curves were averaged in five distinct geological units which constitute the Bohemian Massif (Saxothuringian, Teplá-Barrandean, Sudetes, Moravo-Silesian, and Moldanubian). Estimated error of the averaged dispersion curves are by an order smaller than the inherent variability due to the 3D distribution of seismic velocities within the units. The averaged dispersion data were inverted for 1D layered velocity models including their uncertainty, which are characteristic for each of the geological unit. We found that, overall, the differences between the inverted velocity models are of similar order as the variability inside the geological units, suggesting that the geological specification of the units is not fully reflected into the S-wave propagation velocities on a regional scale. Nevertheless, careful treatment of the dispersion data allowed us to identify some robust characteristics of the area. The vp to vs ratio is anomalously low (~1.6) for all the units. The Moldanubian is the most rigid and most homogeneous part of the Bohemian Massif. Middle crust in the depth range of ~3-15 km is relatively homogeneous across the investigated region, while both uppermost horizon (0-3 km) and lower crust (>15 km) exhibit lower degree of homogeneity.

  11. Geological structures and geochronology of the Gonam Complex in the Gyeonggi Massif, South Korea

    NASA Astrophysics Data System (ADS)

    Kihm, You Hong; Kim, Sung Won

    2013-04-01

    Geological structures and geochronology of the Gonam Complex in the Gyeonggi Massif, South Korea You Hong Kihm and Sung Won Kim The Gonam complex is exposed in the westernmost part of the Gyeonggi Massif, which is recently thought be related with Triassic collision of China. This complex consists of various lithologies such as quartz schist, mica schist, quartzite, marble, leucocratic granite, mafic dyke and alkali granite. The Gonam complex can be divided into three units from south to north. The first is dominated by alternation of quartz schist and mica schist, which are intruded by leucocratic granites and mafic dykes. The second unit is highly sheared and folded quartzite. The last unit is composed of schists and marble intruded by acidic dykes, mafic dykes and foliated syenite. The deformation of the Gonam complex is characterized by one ductile shearing, two generations of folding, and four generations of faulting. The most prominent geological structures developed in the Gonam Complex are ductile structures, such as mylonitic foliations, mineral stretching lineations, sheath folds and oblique folds. At most outcrops the Gonam Complex was strongly sheared and intruded by amphibolitic dykes and leucocratic granites, which are also sheared. Widely developed mylonite indicates the ductile shearing occurred in high temperature metamorphic condition. SHRIMP zircon ages of detrital zircons obtained from schist and quartzite range from 3313 to 1819 Ma indicating the Gonam Complex deposited after Paleoproterozoic. Intrusion ages of foliated leucocratic granite, mafic dyke and foliated syenite are 821 Ma, 812 Ma and 751 Ma, respectively. And massive mafic dyke, syenite and two-mica granite (232~228 Ma) are interpreted as post-collisional igneous activity. These events are similar to those of Qinling-Dabie Belt and suggest that the Gyeonggi Massif is probably correlated to the Qinling-Dabie Belt.

  12. Subsurface Implications of Spatially Variable Seafloor Character on the Atlantis Massif

    NASA Astrophysics Data System (ADS)

    Greene, J. A.; Tominaga, M.; Blackman, D. K.

    2014-12-01

    We documented and mapped the characteristics of the seafloor on the Atlantis Massif, an ocean core complex located at 30°N on the Mid-Atlantic Ridge. Our goal is to investigate the implications of these surficial features, particularly whether their spatial variations might reflect subsurface lithology and geological processes. We utilized data collected during the MARVEL 2000 cruise AT3-60, specifically Alvin videos and rock samples, Argo II digital still photos, and TOBI/DSL-120 side-scan sonar mosaic. The Alvin dives studied occurred over the Central Dome and Eastern Block, which is interpreted as the hanging wall to the detachment that unroofed the dome. We also studied two Argo II dives located over the Central Dome, one over the Eastern Block, and one over the Western Shoulder of the southern dome. The TOBI/DSL-120 side-scan sonar followed a widespread, looped track providing near total coverage of the massif. We classified the character of the seafloor based on imagery, the acoustic reflectivity, and the basic composition of rock samples. To aid in our classification, we merged Argo II still images to produce photo-mosaics displaying tens of meters long transects. We then classified the seafloor as unconsolidated sediment, lithified sediment (a carbonate crust or cap), exposed bedrock, or rubble. To obtain a broader understanding of the Atlantis Massif, we analyzed the distribution of these classes of seafloor. Over the Central Dome and Western Shoulder, we found most seafloor classes present in notable amounts, with many individual areas dominated by a particular type.

  13. La dmocratisation de l'enseignement suprieur au Canada: la face cache de la massification.

    PubMed

    Kamanzi, Pierre Canisius; Doray, Pierre

    2015-02-01

    The increase in available student placements at colleges and universities, the implementation of provincial and federal postsecondary education policies, and the rise of the educational aspirations of families and individuals have all led to the massification of Canadian higher education. Based on Merle's typology of the forms of democratization, this article attempts to revisit the theory of equality of opportunities by critically analyzing the link between massification of higher education and social equity. The results of an analysis of longitudinal data from the (YIT) Youth in Transition Survey show that at the age of 24 in 2008, approximately 77% of young Canadians have pursued studies in a college or university. If access to postsecondary education is now higher, to what extent has it improved social equity? The article shows, in light of the Merle's typology, that mass university education is achieved in part under the seal of a segregative democratization, while college education tends to be egalitarian. L'augmentation de la capacit d'accueil des collges et des universits, la mise en uvre de politiques provinciales et fdrales de dveloppement de l'enseignement postsecondaire et la monte des aspirations scolaires des familles et des individus ont contribu massifier l'enseignement suprieur canadien. En se basant sur la typologie des formes de dmocratisation de Merle, le prsent article tente de revisiter la thorie de l'galit des chances en s'interrogeant sur le lien entre la massification de l'enseignement suprieur et l'quit sociale. Les rsultats obtenus partir de donnes longitudinales provenant de l'Enqute auprs de jeunes en transition (EJET) montrent qu' l'ge de 24 ans en 2008, environ 77% des jeunes Canadiens ont poursuivi des tudes dans un collge ou une universit. Si l'accs aux tudes postsecondaires est aujourd'hui plus lev, dans quelle mesure celui-ci a-t-il amlior l'quit sociale? L'article montre, la lumire de la typologie de Merle, que la massification de l'enseignement universitaire se ralise en partie sous le sceau d'une dmocratisation sgrgative, tandis que l'enseignement collgial a tendance tre galisateur. PMID:25737464

  14. Deglaciation and post-glacial environmental evolution in the Western Massif of Picos de Europa

    NASA Astrophysics Data System (ADS)

    Ruiz-Fernández, Jesús; Oliva, Marc; García, Cristina; López-Sáez, José Antonio; Gallinar, David; Geraldes, Miguel

    2014-05-01

    This study examines the process of deglaciation of the Western Massif of Picos de Europa through field work, geomorphological mapping, sedimentary records and absolute datings of 14C. This massif has several peaks over 2,400 m a.s.l. (Peña Santa de Castilla, 2,596 m; Torre Santa María, 2,486 m; Torre del Mediu, 2,467 m). It is composed mainly by Carboniferous limestones. This area has been intensively affected by karstic dissolution, Quaternary glaciers and fluvio-torrential processes (Miotke, 1968; Moreno et al, 2010; Ruiz-Fernández et al, 2009; Ruiz-Fernández, 2013). At present day, periglacial processes are active at the highest elevations (Ruiz-Fernández, 2013). We have identified four main glacial stages regarding the deglaciation of the massif: (i) maximum advance corresponding to the Last Glaciation, (ii) retreat and stabilization after the maximum advance, (iii) Late Glacial, and (iv) Little Ice Age. Sedimentological studies also contribute data to the understanding of the chronological framework of these environmental changes. The datings of the bottom sediments in two long sequences (8 and 5.4 m) provided a minimum age of 18,075 ± 425 cal BP for the maximum advance stage and 11,150 ± 900 cal BP for retreat and stabilization in the phase following the maximum advance. The ongoing analyses of these sequences at very high resolution will provide new knowledge about the environmental conditions prevailing since the deglaciation of the massif. References Miotke, F.D. (1968). Karstmorphologische studien in der glazial-überformten Höhenstufe der Picos de Europa, Nordspanien. Hannover, Selbtverlag der Geografischen Gessellschaft, 161 pp. Moreno, A., Valero, B.L., Jiménez, M., Domínguez, M.J., Mata, M.P., Navas, A., González, P., Stoll, H., Farias, P., Morellón, M., Corella, J.P. & Rico, M. (2010). The last deglaciation in the Picos de Europa National Park (Cantabrian Mountains, Northern Spain). Journal of Quaternary Science, 25 (7), 1076-1091. Ruiz-Fernández, J. (2013). Las formas de modelado glaciar, periglaciar y fluviotorrencial del Macizo Occidental de los Picos de Europa (Cordillera Cantábrica). Unpublished PhD Thesis, University of Oviedo, 314 pp. Ruiz-Fernández, J., Poblete. M.A., Serrano, P., Martí, C. & García-Ruiz, J.M. (2009). Morphometry of glacial cirques in the Cantabrian Range (Northwest Spain). Zeitschrift für Geomorphologie N. F., 53, 47-68.

  15. Degassing and redox effects in the magma chamber of the Guli massif (Polar Siberia)

    NASA Astrophysics Data System (ADS)

    Ryabchikov, I. D.; Kogarko, L. N.; Kuzmin, D. V.

    2012-04-01

    The Guli massif occupies a large area between the Maymecha and Kotui Rivers at the boundary of the Siberian platform with the Khatanga trough. It has a roughly oval shape of 35-45 km, and, including the two-thirds obscured by Quaternary deposits, has an area of 1500-1600 km2. The Guli massif, like many of the other alkaline-ultrabasic intrusions, is a composite, multi-stage pluton. The predominant rocks of the massif are dunites, which occupy about 60% of the total area, and a range of melanocratic alkaline rocks, which extend over about 30%. The other rock types, including melilitolite, ijolite, alkaline syenite and carbonatite, occupy less than 10% of the area. Dunite intrusives were cut by numerous bodies of Ti-Fe ore pyroxenite (kosvite) that are composed mainly of pyroxene and titanomagnetite with accessory apatite and titanite, and form about 10% of the volume of the dunites. Among the volcanics and dyke rocks in the area surrounding the Guli massif olvine-rich meimechites play substantial role. Variations of Mg# of olivines from dunite indicat presence of cryptic layering, whereas evolution of spinels from chromites to titanomagnetites in less magnesian varieties indicate gradual transition from dunites to kosvites. Original layering is obscured by intense folding. Trace-element diagram normalized to pyrolite and Lu shows that interstitial material present between olivines of dunites is identical to meimechites. This implies that primary magma of the Guli intrusion had meimechite composition. Some zoned olivines show regular decrease in Ni and increase in Mn from core to margin, whereas variation of Ca content in the same grains pass through several maxima and minima. This reflects accumulation of both Ca and CO2 in the residual melt with episodic loss of CO2 leading to the increase in the activity of CaO. Eventually this process leads to the formation of melilite-bearing rocks, alkaline magmas and carbonatites. In many samples of kosvites Ni content in olivines correlates negatively with their Mg#'s. This is opposite to usual behaviour of Ni during the crystallization of olivine-bearing rocks. It may be explained by simultaneous crystallization of the large proportion of magnetite, which in turn indicates highly oxidized nature of this magmatic system. Magma chamber of the Guli intrusion was originally filled with meimechite magma. Its crystallization created huge pile of olivine-rich cumulates. Kosvites, melilite-bearing rocks, alkaline rocks and carbonatites are most likely to have been formed by the crystallization of filter-pressed melts derived from earlier cumulates. The variety of rocks within the Guli magmatic complex are basically result of in situ differentiation.

  16. Petrostructural evolution of ultramafic rocks of the Kalninsky chromite-bearing massif, Western Sayan

    NASA Astrophysics Data System (ADS)

    Chernyshov, A. I.; Yurichev, A. N.

    2013-07-01

    The Kalininsky ultramafic massif is a fragment of lower structural zone of the Kurtushiba ophiolitic belt in the extreme northeastern part of the Western Sayan. The massif is composed largely of rocks making up the dunite-garzburgite banded complex. The northeastern part of the massif is composed mainly of dunite with linear NW-trending chromite-bearing zones, the localization of which is controlled by banding of the dunite-harzburgite complex. Harzburgite and dunite are characterized by inhomogeneous structures and textures caused by nonuniform ductile deformation, which is expressed as heterogeneous extinction, kink bands, and syntectonic and annealing recrystallization. The petrostructural patterns of olivine in harzburgite and dunite provide evidence for three stages of ductile deformation. At the first stage under deep mantle-crustal conditions, the ductile flow of ultramafic rocks developed mainly in a regime of axial compression, high temperature (>1000C), and low strain rate (? < 10-6 s-1), which resulted in translational gliding along the (010)[100] and (100)[001] systems in olivine and enstatite, respectively, in combination with a subordinate role of syntectonic recrystallization. Consequently, the rocks acquired a medium-grained (mesogranular) microstructure. At the second stage, related to the thermal effect on ultramafics, the ductile flow developed under the settings of low strain rate (? < 10-6 s-1) and rising temperature (>1000C). The translational gliding in olivine proceeded largely along (010)[100] and was accompanied by diffusion creep. As the temperature rose, ductile deformation gave way to secondary recrystallization of annealing, which facilitated the growth of olivine grains free of dislocations owing to absorption of individual grains oriented adversely relative to the compression axis and deformed grains saturated with dislocations. As a result, dunite and harzburgite with a coarse-grained porphyroblastic microstructure have been formed. The third stage of ductile flow was apparently related to their transport along deep-seated thrust faults under settings of intense shear deformations at a high temperature (1000C) and strain rate (? >10-4 s-1). The ductile flow in olivine resulted in heterogeneous translational gliding along (010)[100] and accompanied by intense syntectonic recrystallization with the formation of a porphyroblastic microstructure. Chromite mineralization in dunite is controlled by internal banding. Intense ductile flow facilitated the metamorphic separation of linearbanded Cr-spinel segregations. Thus, the results of a petrostructural study show that ultramafic rocks of the Kalninsky massif, ascending to the upper lithosphere, underwent both axial and shear ductile deformations in the mantle and lower crust, and these deformations controlled chromite mineralization.

  17. Une complication rare des liomyomes utrins: hmopritoine massif par rupture de varices

    PubMed Central

    Ymele, Florent Fouelifack; Tsuala, Jovanny Fouogue; Fouedjio, Jeanne Hortence; Nangu, Charlette; De Kayo, Caroline Kayo; Dobgima, Pisoh Walter; Mbu, Robinson Enoh

    2013-01-01

    Les liomyomes utrins sont des causes exceptionnelles d'hmopritoine. Nous rapportons ici le cas d'une femme de 46 ans nullipare, en instance d'une hystrectomie totale indique pour utrus polymyomateux symptomatique. Elle a t opre en urgence pour hmopritoine aigu et massif compliqu de choc hmorragique. L'origine de l'hmopritoine tait la rupture spontane d'une varice du liomyome. Quoique rare l'ventualit d'un hmopritoine caus par un fibrome utrin devrait tre voque devant tout abdomen aigu spontan chez une femme en ge de procrer. La prsence de varices sur les fibromes augmenterait le risque d'hmorragie spontane. PMID:23717724

  18. The Horoman Peridotite Massif: an Example of Ancient Ultraslow-Spreading Ridge Abyssal Peridotites?

    NASA Astrophysics Data System (ADS)

    Shimizu, N.; Warren, J. M.; Frey, F. A.; Takazawa, E.

    2006-12-01

    Ultraslow-spreading ridges (full spreading rate less than 20 mm per year) comprise about one third (lengthwise) of the global ridge system today, and might also have been important in the geologic past, particularly after breakup of large continents. Geochemical studies of abyssal peridotites show that large local- scale (single-dredge to hand specimen scales) variations in isotopic composition, modal abundance of clinopyroxene (CPX), and trace element abundance in CPX are distinct characteristics of ultraslow-spreading ridge peridotites. It is suggested that these local-scale variabilities are produced by melt-rock reaction during melt migration in the mantle (e.g., Warren et al., 2006). We explored using these geochemical characteristics to identify ancient ultraslow-spreading ridge peridotites among "orogenic lherzolite massifs". The Horoman peridotite massif in Hokkaido, Japan, possesses DMM-like initial Nd and Sr isotopic characteristics at the time of melt extraction, and displays large variations in modal CPX (13.2 - 5.2%, only for lherzolites and plagioclase lherzolites) and in trace elements in CPX (e.g., Nd ranges from 0.3 to 10 times C1 chondrite) over a sampling scale length of 150 m. Additionally, there is ample evidence for chromatographic melt-rock reaction in the presence of garnet (Takazawa et al., 1996; Yoshikawa and Nakamura, 2000). These geochemical characteristics are very similar to those observed for the present-day ultraslow-spreading ridge peridotites such as those from the SWIR and Gakkel ridge. A whole-rock Sm-Nd isochron age for the plagioclase lherzolites of 830+/-78 Ma (Yoshikawa and Nakamura, 2000) and a suggestion by Saal et al. (2001) that refertilization of depleted peridotites by a MORB-like magma occurred around 900 Ma, based on the Re-Os systematics, indicate that melt extraction and melt-rock reaction formed the Horoman peridotite massif at 800 to 900 Ma. This time is similar to that, 750 Ma, estimated for formation of the Paleopacific ocean by rifting of the Rodinia supercontinent (e.g., Torsvik, 2003). We suggeset that the Horoman massif could represent abyssal peridotite beneath the Paleopacific ridge when its spreading rate was ultraslow. Saal et al. (2001) J. Petrol., 42, 25-37; Takazawa et al. (1996) Chem. Geol., 134, 3-26; Torsvik (2003) Science, 300, 1379-1381; Yoshikawa and Nakamura (2000) JGR, 105, 2879-2901; Warren et al. (2006) Goldschmidt Conf. Abstract.

  19. Geochemical characteristics of rare earth elements in soil of the Ditru Massif, Eastern Carpathians, Romania

    NASA Astrophysics Data System (ADS)

    Ion, Adriana

    2013-04-01

    The present paper describes the level of rare earth elements in soils developed from Ditr?u massif area for evaluating of the background of these elements and accurate assessment of environmental impact. Also this paper contributed to understanding the important role of parent rocks in pedogenic processes. The Ditr?u Alkaline Massif represent an intrusion body with a internal zonal structure, which was emplaced into pre-Alpine metamorphic rocks of the Bucovinian nappe complex close the Neogene - Quaternary volcanic arc of the Calimani-Guurghiu- Harghita Mountain chain. The center of massif was formed by nepheline syenite, which is surrounded by syenite and monazonite. North-western and north-eastern marginal sectors are composed of hornblende gabbro/hornblendite, alkali diorite, monzodiorite, monzosyenites and alkali granite. Small discrete ultramafic bodies (kaersutite-bearing peridotite, olivine, pyroxenite and hornblendite) and alkali gabbros occur in the Jolotca area. All this rocks are cut by late-stage dykes with a large variety of composition including tinguaite, phonolite, nepheline syenite, microsyenite, and aplite. The types of soils predominant in this zone are lithosoils. These soils are shallow developed, have low content in organic matter and reflects mineralogical and geochemical composition of the bedrock. The soil samples were collected from 70 location for all type of representative rocks (approximately 10 soil sampling points for each type of rock). The samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The pH values of these samples varied from 3.6 to 7.3, in general, the soils from massif area are acid or weakly acidic. The pH controls the abundance of REE in soil, the concentration of REE increases with decreasing pH values. In soil samples analyzed the contents of REE follow the order: Ce > La > Nd > Pr > Sm > Eu > Gd > Dy > Yb > Er > Tb > Ho >Tm. ? REE varied from 52.59 ?g g-1 to 579.2 ?g g-1 , the average is 273.14 ?g g-1. The chemical analysis of soil showed an enrichment in LREE (from La to Eu) and a depletion in HREE (from Gd to Lu). Relatively high levels of LREE concentration in soil are genetically associated with REE mineralization. The soil samples developed on the syenite and nephelin syenite are enriched in HREE. The REE chondrite - normalized plots showed for most soils in the sampling area strongly negative anomalies for cerium and europium, positive anomalies for gadolinium and dysprosium. The distribution of REE in soil is given and controlled by the presence of primary minerals (potasic and plagioclase feldspars) and accessory minerals (zircon, monazite, titanite, allanite, apatite, xenotime, thorite, bastnsite) in bedrock.

  20. Climatically-driven amplification of topography in the Mont Blanc massif, Western Alps

    NASA Astrophysics Data System (ADS)

    Glotzbach, C.; Spiegel, C.; Bernet, M.; van der Beek, P.

    2009-04-01

    The recent (last few My) evolution of topography of the European Alps and its potential climatic controls remains a subject of controversy. Here, we apply numerical thermal modelling (Pecube) to a tunnel transect crossing the Mont Blanc massif in the Western Alps, in order to quantify denudation rates and relief evolution in that area during the last few million years. The estimations benefit from a dense thermochronological dataset of both tunnel and surface samples (Glotzbach et al. 2008), which is complemented by some new apatite fission track (AFT) and apatite (U-Th)/He (AHe) data. AFT ages are identical within error along the tunnel, with ages around 4 Ma, the same hold true for AHe ages with ages around 1.5 Ma. In contrast, forward modelling assuming a scenario including steady-state topography predicts a clear perturbation of AFT and AHe ages and leads to significant misfit between observed and predicted ages. This discrepancy suggests that at least part of the relief is very young (<4 Ma). To better resolve the timing and amount of relief evolution, we applied an inverse modelling approach using the Neighbourhood Algorithm (NA). Initial inversions were run to verify if the sample distribution is capable of detecting relief evolution. For this purpose we generate synthetic ages for the used sample locations in a forward model and tried to recover these parameters using an inversion. Resulting predicted parameters are close to the initial parameters (initial and predicted amplification factors of the topography are 0.2 and 0.1, respectively). In subsequent inversions we used all thermochronological data to predict the best parameters for the relief evolution. Good solutions (low misfit) predict that relief was less pronounced (<0.4 times the modern relief) before 3 to 1 Ma. An inversion based only on the tunnel data (which is more sensitive to relief evolution), yields best solutions for a relief change starting around 1 Ma. We therefore suggest that the main relief change in the Mont Blanc massif happened after around 1 Ma, but probably started to evolve already around 3 Ma. Given this timing and the lack of indications for recent tectonic activity, we suggest that relief development in the Mont Blanc massif is controlled by climate, with intense mid-Pleistocene glaciation leading to rapid valley incision and exhumation. Glotzbach, C., J. Reinecker, M. Danik, M. Rahn, W. Frisch, and C. Spiegel (2008), Neogene exhumation history of the Mont Blanc massif, western Alps, Tectonics, 27, TC4011, doi:10.1029/2008TC002257.

  1. Utilization of digital LANDSAT imagery for the study of granitoid bodies in Rondonia: Case example of the Pedra Branca massif

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Almeidafilho, R.; Payolla, B. L.; Depinho, O. G.; Bettencourt, J. S.

    1984-01-01

    Analysis of digital multispectral MSS-LANDSAT images enhanced through computer techniques and enlarged to a video scale of 1:100.000, show the main geological and structura features of the Pedra Branca granitic massif in Rondonia. These are not observed in aerial photographs or adar images. Field work shows that LANDSAT photogeological units correspond to different facies of granitic rocks in the Pedra Branca massif. Even under the particular characteristics of Amazonia (Tropical Forest, deep weathering, and Quaternary sedimentary covers), an adequate utilization of orbital remote sensing images can be important tools for the orientation of field works.

  2. MASSIF-1: a beamline dedicated to the fully automatic characterization and data collection from crystals of biological macromolecules

    PubMed Central

    Bowler, Matthew W.; Nurizzo, Didier; Barrett, Ray; Beteva, Antonia; Bodin, Marjolaine; Caserotto, Hugo; Delagenière, Solange; Dobias, Fabian; Flot, David; Giraud, Thierry; Guichard, Nicolas; Guijarro, Mattias; Lentini, Mario; Leonard, Gordon A.; McSweeney, Sean; Oskarsson, Marcus; Schmidt, Werner; Snigirev, Anatoli; von Stetten, David; Surr, John; Svensson, Olof; Theveneau, Pascal; Mueller-Dieckmann, Christoph

    2015-01-01

    MASSIF-1 (ID30A-1) is an ESRF undulator beamline operating at a fixed wavelength of 0.969 Å (12.8 keV) that is dedicated to the completely automatic characterization of and data collection from crystals of biological macromolecules. The first of the ESRF Upgrade MASSIF beamlines to be commissioned, it has been open since September 2014, providing a unique automated data collection service to academic and industrial users. Here, the beamline characteristics and details of the new service are outlined. PMID:26524320

  3. MASSIF-1: a beamline dedicated to the fully automatic characterization and data collection from crystals of biological macromolecules.

    PubMed

    Bowler, Matthew W; Nurizzo, Didier; Barrett, Ray; Beteva, Antonia; Bodin, Marjolaine; Caserotto, Hugo; Delagenire, Solange; Dobias, Fabian; Flot, David; Giraud, Thierry; Guichard, Nicolas; Guijarro, Mattias; Lentini, Mario; Leonard, Gordon A; McSweeney, Sean; Oskarsson, Marcus; Schmidt, Werner; Snigirev, Anatoli; von Stetten, David; Surr, John; Svensson, Olof; Theveneau, Pascal; Mueller-Dieckmann, Christoph

    2015-11-01

    MASSIF-1 (ID30A-1) is an ESRF undulator beamline operating at a fixed wavelength of 0.969 (12.8 keV) that is dedicated to the completely automatic characterization of and data collection from crystals of biological macromolecules. The first of the ESRF Upgrade MASSIF beamlines to be commissioned, it has been open since September 2014, providing a unique automated data collection service to academic and industrial users. Here, the beamline characteristics and details of the new service are outlined. PMID:26524320

  4. Initial Os-isotopic composition of Os-Ir-Ru alloys from ultramafic massifs of the Polar Siberia

    NASA Astrophysics Data System (ADS)

    Malitch, K. N.; Badanina, I. Yu.; Kostoyanov, A. I.

    2011-09-01

    This study firstly presents chemical and initial Os-isotopic compositions of Os-Ir-Ru minerals of two ultramafic formations of Polar Siberia, which are exemplified by Guli clinopyroxene-dunite massif of the Maimecha-Kotui Province and the Kunar dunite-harzburgite massif from the Chelyuskin ultramafic belt of the Taimyr Peninsula. The study employed a range of methods, including electron microprobe analysis, negative thermal ionization mass spectrometry (N-TIMS) and laser ablation attached to an inductively coupled plasma mass spectrometry (LA MC-ICP-MS). The majority of platinum-group minerals (PGM) from the Guli massif are Os-(Ir-Ru) solid solutions or Os-rich minerals. At Kunar, minerals of Ru-Os-Ir system (i.e., osmium, ruthenium, iridium and rutheniridosmine) dominate the PGM assemblage. The ruthenium trend in the mineral compositions is due to the formation of these minerals under high pressures and temperatures at considerable depths. The 187Os/188Os values of Os-rich minerals from the Guli massif range from 0.12309 0.00002 to 0.12606 0.00003 ( n = 168). The initial Os-isotopic composition of PGM from the central block of the Guli massif is characterized by the 187Os/188Os values, varying in the range 0.12404-0.12606. Osmiumrich minerals from the southwestern block of the Guli massif are characterized by the least "radiogenic" 187Os/188Os values (i.e., 0.12309-0.12341). Low relative to the chondritic universal reservoir (CHUR) 187Os/188Os values are indicative of a near-to-chondritic source of platinum-group elements (PGE). The most "productive" stage of PGM formation at Guli ( n = 121) is recorded in the time interval of 545-615 Ma. The older model 187Os/188Os ages of osmium minerals are characteristic of the southwestern block of the Guli massif (e.g., 745-760 Ma). The results of the initial Os-isotopic composition for Os-rich alloys are consistent with a model, in which PGM were formed during multi-stage melt depletion events in the mantle. This agrees well with the suggestion that the Guli massif consists of heterogeneous blocks of ultramafic rocks. The 187Os/188Os ratio in the investigated PGM from the Kunar massif varies in a wider range (0.1094-0.1241, n = 28). For the dominant set of PGM samples ( n = 25), regardless of their chemical composition, four groups of the initial osmium isotopic compositions can be estimated, with average 187Os/188Os values of 0.1217 0.0002 ( n = 7), 0.1223 0.0002 ( n = 7), 0.1230 0.0002 ( n = 6) and 0.1238 0.0003 ( n = 6), respectively. The average model Re-Os ages for the defined groups of the Kunar massif are consistent with Late Riphean age interval (e.g., 975 42 Ma, 892 42 Ma, 791 28 Ma and 681 42 Ma, respectively). Significant variations in the 187Os/188Os values and model ages for Ru-Os-Ir alloys at Kunar are close to those from other duniteharzburgite massifs of the Earth, pointing out for their prolonged multi-stage evolution within the upper mantle.

  5. Landscape evolution rates for a cyclic climate within an uplifting massif

    NASA Astrophysics Data System (ADS)

    Vassallo, R.

    2009-04-01

    Quaternary rates of rocks exhumation and transport have been determined from the watersheds to the outlet of a 20-km-long, 2-km-high catchment within an uplifting massif of the Gobi-Altay mountain range (Mongolia). This massif is set in a structurally and chronologically well-studied restraining bend along the Bogd fault, characterized by semi-arid climate alternating long dry and short wet stages with a 100-kyrs periodicity. My approach combines geomorphic field-based investigation and 10Be concentration distribution analysis on bedrock, hillslope colluvia and alluvial sediments from active river or abandoned terraces and fans. The main geomorphic questions addressed in this work are: 1) What are the mechanisms and rates of pre-deposition processes, from sediment formation until deposit and abandonment of alluvial terraces and fans? In particular, I focus the analysis on bedrock exhumation, stocking of colluvia on the hillslopes, and their remobilization and transport within the drainage network. Characteristic times of these processes are poorly known up to date, although they have dramatic importance in landscape evolution modeling. 2) What is the impact of post-deposition processes in the evolution of alluvial surfaces morphology? Analyzing terraces of different ages and at different settings along the river, I compare their relative denudation rates derived from changes in topographic slope and local lowering rate due to matrix remobilization by wind deflation and runoff.

  6. Thermochronology and tectonics of the Mérida Andes and the Santander Massif, NW South America

    NASA Astrophysics Data System (ADS)

    van der Lelij, Roelant; Spikings, Richard; Mora, Andrés

    2016-04-01

    New apatite U-Pb and multiphase 40Ar/39Ar data constrain the high to medium temperature (~ 500 °C-~ 300 °C) thermal histories of igneous and metamorphic rocks exposed in the Mérida Andes of Venezuela, and new apatite and zircon fission track data constrain the ~ 500 °C-~ 60 °C thermal histories of pre-Jurassic igneous and metamorphic rocks of the adjacent Santander Massif of Colombia. Computed thermal history envelopes using apatite U-Pb dates and grain size information from an Early Palaeozoic granodiorite in the Mérida Andes suggest that it cooled from > 500 °C to < 350 °C between ~ 266 Ma and ~ 225 Ma. Late Permian to Triassic cooling is also recorded in Early Palaeozoic granitoids and metasedimentary rocks in the Mérida Andes by numerous new muscovite and biotite 40Ar/39Ar plateau dates spanning 257.1 ± 1.0 Ma to 205.1 ± 0.8 Ma. This episode of cooling is not recognised in the Santander Massif, where 40Ar/39Ar data suggest that some Early Palaeozoic rocks cooled below ~ 320 °C in the Early Palaeozoic. However, most data from pre-Jurassic rocks reveal a regional heat pulse at ~ 200 Ma during the intrusion of numerous shallow granitoids, resulting in temperatures in excess of ~ 520 °C, obscuring late Palaeozoic histories. The generally accepted timing of amalgamation of Pangaea along the Ouachita-Marathon suture pre-dates Late Permian to Triassic cooling recorded in basement rocks of the Mérida Andes by > 30 Ma, and its effect on rocks preserved in north-western South America is unknown. We interpret late Permian to Triassic cooling in the Mérida Andes to be driven by exhumation. Previous studies have suggested that a short phase of shortening and anatexis is recorded at ~ 253 Ma in the Maya Block, which may have been adjacent to the basement rocks of the Mérida Andes in the Late Permian. The coeval onset of exhumation in the Mérida Andes may be a result of increased coupling in the magmatic arc, which was located along the western margin of Pangaea. Triassic extension is documented in the Central Cordillera of Colombia and Ecuador between ~ 240 Ma and ~ 215 Ma, although extension at this time has not been clearly identified in the Mérida Andes or the Santander Massif. Permian to Triassic cooling is not recorded in the structurally isolated Caparo Block in the southern Mérida Andes, suggesting that it may have constituted a distinct fault block in the Triassic. New fission track data from the Santander Massif suggest that it started exhuming at ~ 40 Ma during a period of accelerated convergence between the Nazca/Farallòn Plate and the western margin of South America. Exhumation in the Santander Massif occurred diachronously since ~ 18 Ma in distinct fault blocks at rates of 0.5-1 km/Ma, and may have been driven by east-west compression as a result of the indentation of the Panama-Chocó terrane to western Colombia.

  7. Time series of the northeast Pacific

    NASA Astrophysics Data System (ADS)

    Pea, M. Angelica; Bograd, Steven J.

    2007-10-01

    In July 2006, the North Pacific Marine Science Organization (PICES) and Fisheries & Oceans Canada sponsored the symposium Time Series of the Northeast Pacific: A symposium to mark the 50th anniversary of Line P. The symposium, which celebrated 50 years of oceanography along Line P and at Ocean Station Papa (OSP), explored the scientific value of the Line P and other long oceanographic time series of the northeast Pacific (NEP). Overviews of the principal NEP time-series were presented, which facilitated regional comparisons and promoted interaction and exchange of information among investigators working in the NEP. More than 80 scientists from 8 countries attended the symposium. This introductory essay is a brief overview of the symposium and the 10 papers that were selected for this special issue of Progress in Oceanography.

  8. meeting summary: Second Northeast Regional Operational Workshop.

    NASA Astrophysics Data System (ADS)

    Auciello, Eugene P.

    2001-05-01

    The Second Northeast Regional Operational Workshop, focusing on hydrometeorology in the northeastern United States, was held 7-8 November 2000 in Albany, New York. Sessions in cold season events, warm season events, and operational techniques were presented. A special session, conducted by the National Centers for Environmental Prediction, was devoted to a review of Eta Model performance for the 24-26 January 2000 east coast snowstorm. A summary of workshop presentations is provided.

  9. Northeast utilities submits plan to acquire PSNH

    SciTech Connect

    Not Available

    1990-01-04

    A rate plan for customers of Public Service Company of New Hampshire that calls for annual increases of 5.5% for a period of several years, and then projects no rate increases for the following three years has been submitted to United States bankruptcy court as a reorganization proposal by Northeast Utilities. The proposal includes a merger agreement that would take effect if regulatory approvals and other conditions are not in place by July 1990.

  10. Emplacement depths and radiometric ages of Paleozoic plutons of the Neukirchen-Kdyn? massif: differential uplift and exhumation of Cadomian basement due to Carboniferous orogenic collapse (Bohemian Massif)

    NASA Astrophysics Data System (ADS)

    Bues, Curd; Drr, Wolfgang; Fiala, Ji?i; Vejnar, Zden?k; Zulauf, Gernold

    2002-07-01

    The igneous complex of Neukirchen-Kdyn? is located in the southwestern part of the Tepl-Barrandian unit (TBU) in the Bohemian Massif. The TBU forms the most extensive surface exposure of Cadomian basement in central Europe. Cambrian plutons show significant changes in composition, emplacement depth, isotopic cooling ages, and tectonometamorphic overprint from NE to SW. In the NE, the Vepadly granodiorite and the Smrovice diorite intruded at shallow crustal levels (massif (Veruby and Neukirchen gabbro, Hoher-Bogen metagabbro), which yield Cambrian ages, either intruded or were metamorphosed at considerably deeper structural levels (>20 km). The Teufelsberg (?ert?v kmen) diorite, on the other hand, forms an unusual intrusion dated at 3592 Ma (concordant U-Pb zircon age). K-Ar dating of biotite of the Teufelsberg diorite yields 3424 Ma. These ages, together with published cooling ages of hornblende and mica in adjacent plutons, are compatible with widespread medium to high-grade metamorphism and strong deformation fabrics, suggesting a strong Variscan impact under elevated temperatures at deeper structural levels. The plutons of the Neukirchen area are cut by the steeply NE dipping Hoher-Bogen shear zone (HBSZ), which forms the boundary with the adjacent Moldanubian unit. The HBSZ is characterized by top-to-the-NE normal movements, which were particularly active during the Lower Carboniferous. A geodynamic model is presented that explains the lateral gradients in Cambrian pluton composition and emplacement depth by differential uplift and exhumation, the latter being probably related to long-lasting movements along the HBSZ as a consequence of Lower Carboniferous orogenic collapse.

  11. Geochemistry and petrogenesis of post-collisional ultrapotassic syenites and granites from southernmost Brazil: the Piquiri Syenite Massif.

    PubMed

    Nardi, Lauro V S; Plá-Cid, Jorge; Bitencourt, Maria de Fátima; Stabel, Larissa Z

    2008-06-01

    The Piquiri Syenite Massif, southernmost Brazil, is part of the post-collisional magmatism related to the Neoproterozoic Brasiliano-Pan-African Orogenic Cycle. The massif is about 12 km in diameter and is composed of syenites, granites, monzonitic rocks and lamprophyres. Diopside-phlogopite, diopside-biotite-augite-calcic-amphibole, are the main ferro-magnesian paragenesis in the syenitic rocks. Syenitic and granitic rocks are co-magmatic and related to an ultrapotassic, silica-saturated magmatism. Their trace element patterns indicate a probable mantle source modified by previous, subduction-related metasomatism. The ultrapotassic granites of this massif were produced by fractional crystallization of syenitic magmas, and may be considered as a particular group of hypersolvus and subsolvus A-type granites. Based upon textural, structural and geochemical data most of the syenitic rocks, particularly the fine-grained types, are considered as crystallized liquids, in spite of the abundance of cumulatic layers, schlieren, and compositional banding. Most of the studied samples are metaluminous, with K2O/Na2O ratios higher than 2. The ultrapotassic syenitic and lamprophyric rocks in the Piquiri massif are interpreted to have been produced from enriched mantle sources, OIB-type, like most of the post-collisional shoshonitic, sodic alkaline and high-K tholeiitic magmatism in southernmost Brazil. The source of the ultrapotassic and lamprophyric magmas is probably the same veined mantle, with abundant phlogopite + apatite + amphibole that reflects a previous subduction-related metasomatism. PMID:18506262

  12. Has Massification of Higher Education Led to More Equity? Clues to a Reflection on Portuguese Education Arena

    ERIC Educational Resources Information Center

    Dias, Diana

    2015-01-01

    Massification is an undeniable phenomenon in the higher education arena. However, there have been questions raised regarding the extent to which a mass system really corresponds to an effective democratisation not only of access, but also of success. With regards to access, this article intends, through a brief analysis of the expansion of higher

  13. The Vercors and Chartreuse Massifs at the leading edge of the alpine thrust belt: Tetonic history and petroleum assessment

    SciTech Connect

    Deville, E.; Mascle, A.; Philippe, Y.

    1995-08-01

    The Vercors and Chartreuse Massifs are located at the leading edge of the Western Alps Thrust Belt. They developed in late Miocene-Pliocene times above a major decollement hosted in late Triassic evaporites and/or Liassic marls. The uplift of both massifs led to the oblique and partial inversion of the previous Mesozoic margin of the Southeastern Basin, the thickest onshore sedimentary basin in France. Both massifs are unexplored. The regional geology of eastern France and the results of ten wells located in the near foreland suggest that source rocks are present in late Paleozoic and late Liassic strata, and that fractured sandstones and/or limestones of Triassic/Jurassic age could act as reservoirs. A nonexclusive seismic survey has been shot in 1991 by CGG allowing the first well constrained balanced sections to be drawn across both massifs. They have been used inturn to model the forward kinematics of thrust propagation, and the source rock maturation history, using the {open_quotes}Thrustpack{close_quotes} software developed by IFP and partners.

  14. Has Massification of Higher Education Led to More Equity? Clues to a Reflection on Portuguese Education Arena

    ERIC Educational Resources Information Center

    Dias, Diana

    2015-01-01

    Massification is an undeniable phenomenon in the higher education arena. However, there have been questions raised regarding the extent to which a mass system really corresponds to an effective democratisation not only of access, but also of success. With regards to access, this article intends, through a brief analysis of the expansion of higher…

  15. The Toa Baja Drilling Project, Puerto Rico: Scientific drilling into a non-volcanic island arc massif

    SciTech Connect

    Larue, D.K. )

    1991-03-01

    The Toa Baja Drilling Project was a broad, interdisciplinary experiment to document the in situ geology and geophysics of a non-volcanic island arc massif. This overview provides a brief summary of oil exploration on Puerto Rico that lead up to the present investigation, and summarizes some of the problems addressed by drilling.

  16. The Dilemma and Solutions for the Conflicts between Equality and Excellence in the Massification of Higher Education in Taiwan

    ERIC Educational Resources Information Center

    Hsiou-Huai, Wang

    2012-01-01

    Equality and excellence are two core values underlying many educational endeavors; however, they are often in conflict and controversy. This article intends to examine the dilemma created by such controversies in the context of massification of higher education in Taiwan and attempt to provide solutions from both the theoretical and policy

  17. Possible petrogenetic associations among igneous components in North Massif soils: Evidence in 2-4 mm soil particles from 76503

    NASA Technical Reports Server (NTRS)

    Jolliff, Bradley L.; Bishop, Kaylynn M.; Haskin, Larry A.

    1992-01-01

    Studies of Apollo 17 highland igneous rocks and clasts in breccias from the North and South Massifs have described magnesian troctolite, norite, anorthositic gabbro, dunite, spinel cataclasites, and granulitic lithologies that may have noritic anothosite or anorthositic norite/gabbro as igneous precursors, and have speculated on possible petrogenetic relationships among these rock types. Mineral compositions and relative proportions of plagioclase and plagioclase-olivine particles in samples 76503 indicate that the precursor lithology of those particles were troctolitic anorthosite, not troctolite. Mineral and chemical compositions of more pyroxene-rich, magnesian breccias and granulites in 76503 indicate that their precursor lithology was anorthositic norite/gabbro. The combination of mineral compositions and whole-rock trace-element compositional trends supports a genetic relationship among these two groups as would result from differentiation of a single pluton. Although highland igneous lithologies in Apollo 17 materials have been described previously, the proportions of different igneous lithologies present in the massifs, their frequency of association, and how they are related are not well known. We consider the proportions of, and associations among, the igneous lithologies found in a North Massif soil, which may represent those of the North Massif or a major part of it.

  18. Physicochemical parameters of the melts participating in the formation of chromite ore hosted in the Klyuchevsky ultramafic massif, the Central Urals, Russia

    NASA Astrophysics Data System (ADS)

    Simonov, V. A.; Ivanov, K. S.; Smirnov, V. N.; Kovyazin, S. V.

    2009-04-01

    The results of melt inclusion study are reported for chromites of the Klyuchevsky ultramafic massif, which is the most representative of all Ural ultramafic massifs localized beyond the Main Ural Fault Zone. The massif is composed of a dunite-harzburgite complex (tectonized mantle peridotite) and a dunite-wehrlite-clinopyroxenite-gabbro complex (layered portion of the ophiolitic section). The studied Kozlovsky chromite deposit is located in the southeastern part of the Klyuchevsky massif and hosted in serpentinized dunite as a series of lenticular bodies and layers up to 7-8 m thick largely composed of disseminated and locally developed massive ore. Melt inclusions have been detected in chromites of both ore types. The heated and then quenched into glass melt inclusions and host minerals were analyzed on a Camebax-Micro microprobe. The glasses of melt inclusions contain up to 1.06 wt % Na2O + K2O and correspond to melts of normal alkalinity. In SiO2 content (49-56 wt %), they fit basalt and basaltic andesite. The melt inclusions are compared with those from chromites of the Nurali massif in the southern Urals and the Karashat massif in southern Tuva. The physicochemical parameters of magmatic systems related to the formation of disseminated and massive chromite ores of the Klyuchevsky massif are different. The former are characterized by a wider temperature interval (1185-1120°C) in comparison with massive chromite ore (1160-1140°C).

  19. Seafloor acoustic imagery surrounding the Rainbow massif, Mid-Atlantic Ridge 36N

    NASA Astrophysics Data System (ADS)

    Dunn, R. A.; Canales, J.; Sohn, R. A.; Kakone, E.

    2013-12-01

    The MARINER (Mid-Atlantic Ridge INtegrated Experiments at Rainbow) seismic and geophysical mapping experiment was carried out in April-May 2013 and was designed to examine the relationship between tectonic rifting, heat/melt supply, and oceanic core complex formation at a non-transform offset (NTO) of the Mid-Atlantic Ridge (36N) the site of the ultramafic-hosted Rainbow hydrothermal system. One component of this experiment was dense acoustic multibeam backscatter and bathymetry data collection. We present acoustic imagery of the seafloor extending across two segments of the Mid-Atlantic Ridge separated by the Rainbow NTO massif. The acoustic imagery provides a broad view of the character of the ridge system, emphasizing the strong variability of seafloor morphology, tectonics, and lava emplacement and reveals the general tectono-magmatic setting of the Rainbow massif. The amplitude data were collected via a hull-mounted multi-beam sonar system (Kongsberg EM-122) aboard the R/V Marcus G. Langseth. The multi-fold, multi-directional coverage of the amplitude data allows for a compilation of all data into a common grid, as is usually done for depth data. Corrections for amplitude loss and grazing angle, in combination with multiple data coverage averages out noisy data, local slope dependence, and removes along-track artifacts that tend to be endemic to sonar images. The benefit is a complete sonar image for the area that can be examined with little distortion due to artifacts, and whose features can be interpreted as being principally derived from the intrinsic reflectivity of the seafloor rather than from look-direction and local seafloor slope. The main features of the image include: (1) newer seafloor within the axial valleys with some discernible individual lava flows; (2) large and small fault scarps and possible fissure systems; (3) sediment-filled basins; (4) terrains composed nearly entirely of small volcanic cones; (5) volcanic ridges; (6) regions of shallow topography exhibiting low sedimentation. The Rainbow massif itself consists of a mixture of high and low backscatter amplitudes, reflective of a complex tectonic and sedimentation history.

  20. The seismotectonic significance of the 2008-2010 seismic swarm in the Brabant Massif (Belgium)

    NASA Astrophysics Data System (ADS)

    Van Noten, Koen; Lecocq, Thomas; Shah, Anjana K.; Camelbeeck, Thierry

    2015-04-01

    Structural interpretations of the tectonic grain of orogenic mountain belts have often been based on the study of potential field data. The steep architecture of mountain belts can be highlighted by the inclination of the magnetic field and by the persistence of aeromagnetic lineaments with depth. With respect to seismology, matched filtering has proven to be very useful for linking seismicity with deep-seated tectonic structures by separating short-wavelength anomalies, that originate from shallow depths, from long-wavelength anomalies that generally originate at greater depths. Between 2008 and 2010 more than 300 low-magnitude earthquakes occurred 20 km SE of Brussels (Belgium). Thanks to a locally deployed temporary seismic network covering the epicentral area, very small events could be detected (magnitude variation between ML -0.7 and ML 3.2). The spatial distribution of the hypocenter locations show a dense spatial cluster displaying a narrow, 1.5-km long, NW-SE oriented fault zone at a depth range between 5 and 7 km, located in the Cambrian basement rocks of the Lower Palaeozoic Anglo-Brabant Massif. Its NW-SE orientation is in agreement with the structural grain in this part of the Brabant Massif. In order to find a relevant tectonic structure that could correspond to the 2008-2010 seismic swarm, we present a full seismotectonic analysis linking local geology to the seismic swarm. A systematic filtering approach was applied in which the magnetic field was carefully bandpass filtered to generate different aeromagnetic maps that highlight sources near the hypocenter depths. Filtering demonstrates that the structure responsible for the seismic swarm is limited in length as it is bordered at both ends by magnetic lineaments with different orientations than the seismic swarm. These observations explain the rather limited spatial distribution of the swarm, both in a vertical and horizontal direction. Although few of the largest historical seismic events in Belgium occurred within the borders of the Brabant Massif, the limited fault length thus suggests that, given its favourable orientation to reactivation in the current stress configuration, it potentially could result in a reduced seismic hazard for this region.

  1. Exploring the Notion That Subduction Erosion Has Removed or Submerged Costa Rica's Early Tertiary Arc Massifs

    NASA Astrophysics Data System (ADS)

    Scholl, D. W.

    2007-05-01

    Arc igneous rocks of Paleocene, Eocene, and Oligocene age are widely exposed in the southern, coastal region of Panama (Lissinna et al., EGU abstract, 2006). These rocks intrude or overlie mafic basement rock of the Caribbean Large Igneous Province (CLIP) of Late Cretaceous age that extends to the east to underlie the Caribbean Basin and form the Caribbean plate. Immediately west of Panama, in coastal Costa Rica, exposures of CLIP basement are not intruded or overlain by arc magmatic rocks of early Tertiary age. EXPLANATIONS: Potentially, the early Tertiary subduction zone that dipped beneath the Pacific margin of Panama did not extend to the west, thus no arc magmatism occurred where Costa Rica presently exists. Alternatively, the subduction zone bordering the Pacific edge of the CLIP extended below Costa Rica but former exposures of early Tertiary arc magmatic rocks piled there have been erosionally removed or buried beneath Miocene and younger arc massifs of interior mountain belts. EXPLORING A SUBDUCTION EROSION EXPLANATION Onshore and offshore evidence documents that subduction erosion thins and truncates the submerged rock framework of the Middle and South America forearc. The eroded (removed) material is transported toward and into the mantle within the subduction channel separating the upper plate of the forearc and lower plate of the subducting oceanic crust. The long-term (greater than 10 Myr) rate of truncation (i. e., migration of the trench toward a fixed, onshore reference) averages 2 to 3 km/Myr. Because of the subduction of the aseismic Cocos Ridge beneath Costa Rica, during at least the past 4 to 5 Myr the rate of truncation at this margin has been much higher. It is proposed that during the past 50 Myr subduction erosion has truncated the Costa Rica forearc by at least 100 km and either obliterated or deeply submerged arc massifs of early Tertiary age. Their exposed presence to the east in neighboring Panama reflects the circumstance that since the early Miocene the Panama sector of the Middle America margin has been a transform margin separating the Cocos and Caribbean plates, thus subduction erosion here has been minimal. During the past 25 Myr the virtual lack of subduction erosion along the Panama margin has thus preserved arc massif evidence of the early Tertiary subduction of Pacific ocean crust beneath the western edge of the CLIP, but similar evidence has been destroyed or submerged along the neighboring Costa Rica margin.

  2. Mantle anisotropy of the Bohemian Massif as seen by SKS-wave splitting

    NASA Astrophysics Data System (ADS)

    Vecsey, Ludek; Plomerova, Jaroslava; Babuska, Vladislav

    2014-05-01

    The Bohemian Massif (BM) assembled during the collision of Laurasia (Laurentia-Baltica) and Gondwana as a part of the Armorican Terrane Assemblage. It represents the estern-most outcrop of the European Variscan belt. The detailed tomographic and seismic anisotropy research of the deep structure of the BM has proceeded in several passive seismic experiments: BOHEMA I (2001-2003), BOHEMA II (2004-2005), BOHEMA III (2005-2006), PASSEQ (2006-2008) and Eger Rift (2007-2011). During these periods, the whole massif was stepwise covered by networks of temporal short-period and broad-band stations that recorded large amount of data from teleseismic events. The inferences from seismic anisotropy image the Bohemian Massif as a mosaic of microplates with a rigid mantle lithosphere preserving a fossil olivine fabric. The mantle domains can be associated with the tectonic units recognized by geological studies: Saxothuringian (ST), Tepl-Barrandian (TB), Moldanubian (MB) and finally Moravian (M) and Silesian (S) parts of the MS Zone, overlying the Brunovistulian mantle lithosphere. In this contribution, we concetrate on the large-scale mantle anisotropy modelled from splitting of SKS waves and their particle motion (PM). An advantage of using PM analysis is its ability to employ even events with lower signal-to-noise ratio (SNR) that are otherwise not usable for splitting analysis. To improve results of splitting analysis of signals distorted by noise, we use stacking of individual splitting measurements from waves closely propagating through the mantle. Another way of improving our analysis is a stacking of individual splittings of a single event measured at nearby stations. On average, the fast shear waves are polarized in the E-W direction in the ST, MD, TB units, but exhibit different regional variations of the splitting parameters in dependence on back-azimuths. Thus, different lithosphere mantle fabrics in the ST, MD and TB units were modelled. Moreover, the ST unit can be divided in two parts differing by about 30 in the fast S polarization directions. The boundary correlates with the geologically mapped Saxonian Lineament. To the north of the BM, the fast S polarizations significantly change. Within the BM, mean azimuths of fast S polarizations calculated for opposite back-azimuths differ. This is one of indications of the directional dependence of shear-wave splitting due to wave propagation through an anisotropic medium with a generally inclined symmetry axis. Anisotropic models with inclined symmetry axes are consistent with results derived from modelling directional variations of P-wave residuals.

  3. Geothermobarometry of basaltic glasses from the Tamu Massif, Shatsky Rise oceanic plateau

    NASA Astrophysics Data System (ADS)

    Husen, Anika; Almeev, Renat R.; Holtz, Franois; Koepke, Jrgen; Sano, Takashi; Mengel, Kurt

    2013-10-01

    We present the results of a petrological study of core samples from Tamu Massif (Site U1347), recovered during the Shatsky Rise Integrated Ocean Drilling Program (IODP) Expedition 324. The basaltic glasses from Site U1347 are evolved tholeiitic basalts containing 5.2-6.8 wt% MgO, and are principally located within the compositional field of mid-ocean ridge basalts (MORBs) but they have systematically higher FeO, lower Al2O3, SiO2, and Na2O concentrations, and the CaO/Al2O3 ratios are among the highest known for MORBs. In this sense, glasses from Site U1347 more closely resemble basaltic magmas from the Ontong Java Plateau (OJP), although they still have lower SiO2 concentrations. In contrast to MORB and similar to OJP, our fractionation corrected values of Na2O and CaO/Al2O3 indicate more than 20% of partial melting of the mantle during the generation of the parental magmas of Tamu Massif. The water contents in the glasses, determined by midinfrared Fourier transform infrared (FTIR) spectroscopy, are MORB-like, and vary between 0.18 and 0.6 wt% H2O. The calculated pressure (P)-temperature (T) conditions at which the natural glasses represent cotectic olivine-plagioclase-clinopyroxene compositions range from 0.1 to 240 MPa and 1100 to 1150C reflecting magma storage at shallow depth. The variation of the glass compositions and the modeled P-T conditions in correlation with the relative ages indicate that there were at least two different magmatic cycles characterized by variations in eruptive styles (massive flows or pillow lavas), chemical compositions, volatile contents, and preeruptive P-T conditions. Each magmatic cycle represents the progressive differentiation in course of polybaric crystallization after the injection of a more primitive magma batch. Magma crystallization and eruption episodes are followed by magmatic inactivity reflected in the core sequence by a sedimentary layer. Our data for Tamu Massif demonstrate that, similar to Ontong Java ocean Plateau, the crystallization beneath Shatsky Rise occurs at different crustal levels.

  4. Thematic mapping of likely target areas for the occurence of cassiterite in the Serra do Mocambo (GO) granitic massifs using LANDSAT 2 digital imaging

    NASA Technical Reports Server (NTRS)

    Almeidofilho, R. (Principal Investigator)

    1984-01-01

    The applicability of LANDSAT/MSS images, enhanced by computer derived techniques, as essential tools in mineral research was investigated and the Serra do Mocambo granitic massif was used as illustration. Given the peculiar factors founded in this area, orbital imagery permitted the delineation of potential target areas of mineralization occurrences, associated to albitized/greisenized types. Follow up prospection for primary tin deposits in this granitic massif should be restricted to the delineated areas which are less than 5% of the total superficial area of the massif.

  5. 5. VIEW, LOOKING NORTHEAST, SHOWING BRIDGE COUNTERWEIGHT New York, ...

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

    5. VIEW, LOOKING NORTHEAST, SHOWING BRIDGE COUNTERWEIGHT - New York, New Haven & Hartford Railroad, Niantic Bridge, Spanning Niantic River between East Lyme & Waterford, Old Lyme, New London County, CT

  6. OBLIQUE VIEW, REAR ELEVATION, LOOKING NORTHEAST Mountain Home Air ...

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

    OBLIQUE VIEW, REAR ELEVATION, LOOKING NORTHEAST - Mountain Home Air Force Base 1958 Senior Officers' Housing, General's Residence, Rabeni Street (originally Ivy Street), Mountain Home, Elmore County, ID

  7. 25. EAST FRONT, VIEW FROM NORTHEAST (AFTER RECONSTRUCTION OF ADJOINING ...

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

    25. EAST FRONT, VIEW FROM NORTHEAST (AFTER RECONSTRUCTION OF ADJOINING BUILDINGS) - Decatur House, National Trust for Historic Preservation, 748 Jackson Place Northwest, Washington, District of Columbia, DC

  8. Looking northeast at west bunkhouse, new "shower" houses and school ...

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

    Looking northeast at west bunkhouse, new "shower" houses and school building - Kennecott Copper Corporation, West Bunkhouse, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  9. 3. MAGAZINE P STAIRWAY ENCLOSURE, LOOKING NORTHEAST. NIKE Missile ...

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

    3. MAGAZINE P STAIRWAY ENCLOSURE, LOOKING NORTHEAST. - NIKE Missile Base C-84, Underground Storage Magazines & Launcher-Loader Assemblies, Easternmost portion of launch area, Barrington, Cook County, IL

  10. 11. VIEW NORTHEAST, DETAIL OF BRIDGE BEARING AT SOUTHEAST CORNER, ...

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

    11. VIEW NORTHEAST, DETAIL OF BRIDGE BEARING AT SOUTHEAST CORNER, SHOWING WELDED REINFORCEMENT - Perkins Corner Bridge, Spanning Willimantic River at Flanders & Cider Mill Roads, Coventry, Tolland County, CT

  11. Perspective view of east entrance from northeast National Home ...

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

    Perspective view of east entrance from northeast - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Building, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  12. 20. Everett Weinreb, photographer ARRIVAL SIGNBOARD, RECEPTION HALL, LOOKING NORTHEAST ...

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

    20. Everett Weinreb, photographer ARRIVAL SIGNBOARD, RECEPTION HALL, LOOKING NORTHEAST - Los Angeles Union Passenger Terminal, Tracks & Shed, 800 North Alameda Street, Los Angeles, Los Angeles County, CA

  13. PERSPECTIVE VIEW OF WEST AND SOUTH FACADES LOOKING NORTHEAST ...

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

    PERSPECTIVE VIEW OF WEST AND SOUTH FACADES LOOKING NORTHEAST - Pennsylvania Furnace, Ironmaster's Privy, West of State Route 45, South of Centre County line, Pennsylvania Furnace, Huntingdon County, PA

  14. PERSPECTIVE VIEW OF SOUTH SIDE OF HOUSE LOOKING NORTHEAST ...

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

    PERSPECTIVE VIEW OF SOUTH SIDE OF HOUSE LOOKING NORTHEAST - Pennsylvania Furnace, Ironmaster's Mansion, West of State Route 45, South of Centre County line, Pennsylvania Furnace, Huntingdon County, PA

  15. 36. TURBINE HALL, NEW TURBO GENERATOR, LOOKING NORTHEAST Philadelphia ...

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

    36. TURBINE HALL, NEW TURBO GENERATOR, LOOKING NORTHEAST - Philadelphia Electric Company, Richmond Power Station, Southeast end of Lewis Street along Delaware River, Philadelphia, Philadelphia County, PA

  16. 4. Hospital Point, Saunders Monument, view to northeast Portsmouth ...

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

    4. Hospital Point, Saunders Monument, view to northeast - Portsmouth Naval Hospital, Bounded by Elizabeth River, Crawford Street, Portsmouth General Hospital, Parkview Avenue, & Scotts Creek, Portsmouth, Portsmouth, VA

  17. 1. OVERVIEW OF MAIN HOSPITAL, NORTHEAST CORNER. Presidio of ...

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

    1. OVERVIEW OF MAIN HOSPITAL, NORTHEAST CORNER. - Presidio of San Francisco, Letterman General Hospital, Building No. 27, Letterman Hospital Complex, Edie Road, San Francisco, San Francisco County, CA

  18. 5. Hospital Point, northeast bulkhead (typical), view to northwest ...

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

    5. Hospital Point, northeast bulkhead (typical), view to northwest - Portsmouth Naval Hospital, Bounded by Elizabeth River, Crawford Street, Portsmouth General Hospital, Parkview Avenue, & Scotts Creek, Portsmouth, Portsmouth, VA

  19. VIEW OF CENTRAL INTERIOR SPACE, FACING NORTHEAST. Douglas Aircraft ...

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

    VIEW OF CENTRAL INTERIOR SPACE, FACING NORTHEAST. - Douglas Aircraft Company Long Beach Plant, Aircraft Parts Shipping & Receiving Building, 3855 Lakewood Boulevard, Long Beach, Los Angeles County, CA

  20. Elevation of grove looking northeast toward Washington Monument 1910 ...

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

    Elevation of grove looking northeast toward Washington Monument - 1910 Japanese Flowering Cherry Trees , East Potomac Golf Course, East Potomac Park, Hains Point vicinity, Washington, District of Columbia, DC

  1. View looking northeast of south gable end of warehouse wing ...

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

    View looking northeast of south gable end of warehouse wing - Kennecott Copper Corporation, Company Store & Warehouse, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  2. Looking northeast across transfer table pit at Boiler Shop (Bldg. ...

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

    Looking northeast across transfer table pit at Boiler Shop (Bldg. 152) - Atchison, Topeka, Santa Fe Railroad, Albuquerque Shops, Boiler Shop, 908 Second Street, Southwest, Albuquerque, Bernalillo County, NM

  3. Looking northeast at interior of Machine Shop (Bldg. 134) ...

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

    Looking northeast at interior of Machine Shop (Bldg. 134) - Atchison, Topeka, Santa Fe Railroad, Albuquerque Shops, Machine Shop No. 2, 908 Second Street, Southwest, Albuquerque, Bernalillo County, NM

  4. Looking Northeast Along Hallway between Pellet Plant and Oxide Building, ...

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

    Looking Northeast Along Hallway between Pellet Plant and Oxide Building, including Virgin Hopper Bins - Hematite Fuel Fabrication Facility, Pellet Plant, 3300 State Road P, Festus, Jefferson County, MO

  5. 4. Perspective view of platform, looking northeast. Delaware, Lackawanna ...

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

    4. Perspective view of platform, looking northeast. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Scrap Platform, 350 feet South of South Washington Avenue & River Street, Scranton, Lackawanna County, PA

  6. 6. Northeast elevation of single bin. Delaware, Lackawanna & ...

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

    6. Northeast elevation of single bin. - Delaware, Lackawanna & Western Railroad, Scranton Yards, Scrap Platform, 350 feet South of South Washington Avenue & River Street, Scranton, Lackawanna County, PA

  7. Northeast and northwest elevations. View to south Flint Creek ...

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

    Northeast and northwest elevations. View to south - Flint Creek Hydroelectric Project, Powerhouse, Approximately 3 miles southeast of Porters Corner on Powerhouse Road, Philipsburg, Granite County, MT

  8. View of exterior circumferential path at northeast side of building ...

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

    View of exterior circumferential path at northeast side of building beneath trellis, looking southeast - National Zoological Park, Bird House, 3001 Connecticut Avenue NW, Washington, District of Columbia, DC

  9. Northwest side, northeast part, looking southeast, note fire alarm box ...

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

    Northwest side, northeast part, looking southeast, note fire alarm box at right - Mare Island Naval Shipyard, Guard House & Barracks, Railroad Avenue near Eighteenth Street, Vallejo, Solano County, CA

  10. Pyroclastic chronology of the Sancy stratovolcano (Mont-Dore, French Massif Central): New high-precision 40Ar/39Ar constraints

    NASA Astrophysics Data System (ADS)

    Nomade, Sbastien; Scaillet, Stphane; Pastre, Jean-Franois; Nehlig, Pierre

    2012-05-01

    The Sancy (16 km2) is the youngest of the two stratovolcanoes that constitute the Mont-Dore Massif (Massif Central, France). The restricted number of high precision radio-isotopic ages currently limits our knowledge of the pyroclastic chronology of this edifice which is the source of many tephra layers detected in middle Pleistocene sequences in southeast Europe. To improve our knowledge of the building phases of this stratovolcano, we collected thirteen pyroclastic units covering the entire proximal record. We present 40Ar/39Ar single grain laser dating performed in the facility hosted at the LSCE (Gif-sur-Yvette, France). The 40Ar/39Ar ages range from 1101 11 ka to 392 7 ka (1? external). Four pyroclastic cycles lasting on average 100 ka were identified (C. I to C. IV). C. I corresponds to the earlier explosive phase between 1101 ka and 1000 ka and starts about 100 ka earlier than previously thought. The second pyroclastic cycle (C. II) is the main pyroclastic episode spanning from 818 to 685 ka. This cycle is constituted of a minimum of 8 major pyroclastic eruptions and includes a major event that corresponds to a large plinian eruption at 719 10 ka (1? external) and recorded as a 1.4 m thick layer 60 km south-east of the Sancy volcano. The link between this large eruption and formation of a caldera stays however, hypothetical. The third pyroclastic cycle (C. III) found in the northeastern part of the Sancy (Mont-Dore valley) spanned from 642 to 537 ka. Finally, the youngest pyroclastic cycle (C. IV) starts at 392 ka and probably ends around 280 ka. The age versus geographic location of each pyroclastic cycle indicates three preferential directions of channeling of the pyroclastic events and/or collapse of the volcanic edifice: northwest to west (C. I), southeast (C. II) and finally north to northeast (C. III and IV). The new high precision 40Ar/39Ar age for the Queureuilh bas pyroclastic unit (642 9 ka) is identical within error with the U/Pb age obtained by Cocherie et al. (2009) [Geochimica et Cosmochimica Acta, 73, 1095-1108] and suggests a short residence time of the magma in a shallow, short-lived, small magmatic chamber. Finally, the source of the t21d tephra layer found in the Pinico Sllere varved sequence (Northern Italy) is not the Rivaux pumice flow as proposed by Brauer et al. (2007) [Journal of Quaternary Science 22, 85-96] and neither one of the C. II pyroclastic units as suggested by Roulleau et al. (2009) [Quaternary International 204, 31-43]. Accordingly, the source for the t21d layer has yet to be found at Sancy or elsewhere.

  11. Oxidation state of the lithospheric mantle beneath the Massif Central,France

    NASA Astrophysics Data System (ADS)

    Uenver-Thiele, L.; Woodland, A. B.; Downes, H.; Altherr, R.

    2012-04-01

    The Tertiary and Quaternary volcanism of the French Massif Central sampled the underlying subcontinental lithospheric mantle (SCLM) in the form of xenoliths over a wide geographic area of ~20.000km2. Such an extensive distribution of xenoliths provides an unique opportunity to investigate regional variations in mantle structure and composition. On the basis of textural and geochemical differences, Lenoir et al. (2000) and later Downes et al. (2003) identified two distinct domains in the SCLM lying north and south of latitude 45 30' N, respectively. The northern domain is relatively refractory, but has experienced pervasive enrichment of LREE. The southern domain is generally more fertile, exhibiting depletion in LREE. A metasomatic overprint has developed to variable extents in many xenolith suites. The different histories of these two juxtaposed blocks of SCLM should also be reflected in their oxidation state, with local variations also to be expected due to metasomatic interactions. For example, if carbonate-melt metasomatism played a role in the LREE enrichment of the northern domain (Lenoir et al. 2000; Downes et al. 2003), then such mantle should be relatively oxidised. Since surprisingly little redox data are currently available, we are undertaking a study to determine the oxidation state of the SCLM beneath the Massif Central over the largest geographical area possible. All xenoliths investigated are spinel peridotites, mostly with protogranular textures (although some samples are porphyroclastic or equigranular). Most samples are nominally anhydrous although minor amphibole is present in some xenolith suites. Major element compositions of the individual minerals were determined by microprobe. Two-pyroxene temperatures (BKN) range from 750 to ~1200 C. Ferric iron contents of spinel were determined by Mssbauer spectroscopy and gave a range of Fe3+/ Fetot from 0.191 to 0.418, with a conservative uncertainty of 0.02. These data were used to calculate oxygen fugacity (fO2) of the peridotites using the Nell-Wood calibration for the equilibrium between olivine, orthopyroxene and spinel (Wood et al. 1990) and are referenced to the fayalite-magnetite-quartz (FMQ) redox buffer. Preliminary results yield ?log(fO2) values between FMQ-0.17 and FMQ+1.65 log units. In this fO2 range propagated uncertainties are on the order of 0.1 log units. Although there is some overlap, localities from the northern block tend to record higher values (>FMW+0.9). In the south, fO2values from a number of localities cluster around FMQ+0.3 to FMQ+0.6, with higher values associated with the occurrence of amphibole in the xenoliths. The higher values (>FMQ+1) testify to localised metasomatic interaction in the SCLM, possibly related to melt migration during earlier phases of magmatic activity in the region. This hypothesis is also consistent with lower fO2 values observed at one locality (Fraisse) on the northern block that is significantly older and thus sampled the mantle prior to the subsequent metasomatic activity in this block of SCLM. Downes H., Reichow M.K., Mason P.R.D., Beard A.D., Thirlwall M.F. (2003) Mantle domains in the lithosphere beneath the French Massif Central: trace element and isotopic evidence from mantle clinopyroxenes. Chem. Geol., 200, 71-87. Lenoir, X., Garrido, C.J., Bodinier, J.-L., Dautria, J.-M. (2000) Contrasting lithospheric mantle domains beneath the Massif Central (France) revealed by geochemistry of peridotite xenoliths. Earth Planet. Sci. Lett. 181, 359-375. Wood B.J., Bryndzia L.T., Johnson K.E. (1990) Mantle oxidation state and its relation to tectonic environment. Science, 248, 337-345.

  12. Permafrost detection in the headwalls of receding glaciers at the Dachstein Massif, Northern Calcareous Alps, Austria

    NASA Astrophysics Data System (ADS)

    Rode, Matthias; Gitschthaler, Christoph; Schnepfleitner, Harald; Kellerer-Pirklbauer, Andreas; Sass, Oliver

    2014-05-01

    The Northern Calcareous Alps cover a large area of the Austrian Alps forming a boundary zone between the Alpine Foreland to the north and the crystalline Central Alps to the south. Generally, climate in this area is more maritime compared to the mountain ranges further south. Few small glaciers are to be found mostly on north-facing slopes. The Northern Calcareous Alps reach maximum elevations of about 3000 m asl. Some of highest summits are to be found are located in the Dachstein Massif reaching 2995 m asl (47 28' 32? N, 13 36' 23? E). Occurrence, thickness and thermal regime of permafrost at this mountain massif are widely unknown and knowledge is based on simulations only. In contrast, the glaciation changes at this mountain massif (e.g. Schladminger and Hallsttter glaciers) have been well documented for decades. Within the framework of the research project ROCKING ALPS - dealing with frost weathering and rockfall in alpine regions - knowledge of permafrost distribution in the headwalls surrounding the receding glaciers is substantial to understand rock decay. For this reason, several techniques have been applied in order to detect bedrock permafrost. During the winter of 2012 22 i-buttons (temperature sensors) were attached to rock walls with different orientations but at similar elevations (2600-2700 m asl). Most of these sites were later covered by an insulating winter snow cover therefore allowing the calculation of the base temperature of the winter snow cover (BTS). These BTS data have been used as a first indicator of permafrost presence. In selected rock walls of several mountains in the massif - Koppenkarstein (2863 m asl), Dirndln (2829 m asl) and Gjaidstein (2794 m asl) - additional 2D-geoelectric surveys (five ERT profiles with a length of 100 m and 2 m electrode spacing) were measured in summer 2013. The high resistivities (> 50.000 ohm.m) at about 1.5 m depth and deeper strongly suggest permafrost existence inside the bedrock at all sites. Interestingly, bedrock permafrost was also detected at an immediate glacier margin which has been ice-free for 2-3 decades at maximum. Possibly the glacier at this site was too thin to have a sufficient insulating effect on the rock and hence was cold-based in this position. Alternatively permafrost aggradation occurred rapidly in the few last decades at this site. A new and innovative method in geomorphology and permafrost research is the use of infrared photography. By using this method the gaps between the punctual temperature sensors and the profile lines of the geoelectric measurements can get closed. By using infrared photography it was possible to visualize patterns and amplitudes of the diurnal variations of the surface temperature. First results showed a faster and deeper cooling of the permafrost areas compared to non-permafrost rocks, which is in accordance with the BTS and ERT data.

  13. Mineral compositions of plutonic rocks from the Lewis Hills massif, Bay of Islands ophiolite

    NASA Technical Reports Server (NTRS)

    Smith, Susan E.; Elthon, Don

    1988-01-01

    Mineral compositions of residual and cumulate rocks from the Lewis Hills massif of the Bay of Islands ophiolite complex are reported and interpreted in the context of magnetic processes involved in the geochemical evolution of spatially associated diabase dikes. The mineral compositions reflect greater degrees of partial melting than most abyssal peridotites do and appear to represent the most depleted end of abyssal peridotite compositions. Subsolidus equilibration between Cr-Al spinal and olivine generally has occurred at temperatures of 700 to 900 C. The spinel variations agree with the overall fractionation of basaltic magmas producing spinels with progressively lower Cr numbers. The compositions of clinopyroxenes suggest that the fractionation of two different magma series produced the various cumulate rocks.

  14. Physical-Chemical Factors Affecting the Low Quality of Natural Water in the Khibiny Massif

    NASA Astrophysics Data System (ADS)

    Mazukhina, Svetlana; Masloboev, Vladimir; Chudnenko, Konstantin; Maksimova, Viktoriia; Belkina, Natalia

    2014-05-01

    One peculiarity of the Khibiny Massif is its spatial location. Rising over 1000 m above the surrounding hilly land and thus obstructing the passage of air masses, it promotes condensation and accumulation of surface and underground water. Annual precipitation here amounts to 600-700 mm in the valleys and up to 1600 mm on mountainous plateaus. Using this water for drinking and household purposes is problematic due to excess Al and F concentrations and high pH values. Now it is known that in its profile, the Massif is represented by three hydrogeological subzones: the upper (aerated), medium and lower ones. The upper subzone spreads throughout the Massif and is affected by the local drainage network and climatic conditions. The medium subzone is permanently saturated with underground water flowing horizontally to sites of discharge at the level of local river valleys and lakes. The fissure-vein water in the lower subzone is confined to tectonic fractures and faults in the so far underexplored, deeper parts of the Massif. Being abundant, this water ascends under high pressure. At places, water has been observed spurting from as deep as 700 m, and even 960 m. In the latter case, the temperature of ascending water was higher than 18 centigrade (Hydrogeology of the USSR, V. 27, 1971). This work was undertaken to reveal the nature of the low quality of water in the Khibiny by using physical-chemical modeling (software package Selector, Chudnenko, 2010). Processes of surface and underground water formation in the Khibiny were examined within a physical-chemical model (PCM) of the "water-rock-atmosphere-hydrogen" system. In a multi-vessel model used, each vessel represented a geochemical level of the process interpreted as spatiotemporal data - ? (Karpov, 1981). The flow reactor consisted of 4 tanks. In the first tank, water of the Kuniok River (1000 L) interacted with atmosphere and an organic substance. The resulting solution proceeded to tanks 2-4 containing with underlying rocks (100g of each) to interact with them following the preset process level, the water-rock ratio being ? = 1.0; 0.8; 0.6; 0.2 at temperatures (5, 5, 3, 3 centigrade) and pressures (1, 2, 2, 3 bar), respectively. The model had been reliably verified in the aeration zone monitored in the course of the years 2001 and 2010. Analysis of the chemical composition of deeper water-bearing strata has required to increase the intensity of the water-rock interactions in tank 3 (from 0.2 to 0) and tank 4 (from 0 to -0.2) and simultaneously increase the temperature: (5, 10, 10 centigrade) in the third and (10, 18, 25 centigrade) in the fourth. At the value of ?= -0.2 in the temperature range of 18-25 centigrade, the component contents in tank 4 were observed to change (mg/l): Al (8.10-4 -1.10-3), HCO3- (67-69), Na (25-26,9), Cl (6-6,38), F(0.522-0.882) giving rise to new mineral phases, which agreed with the monitoring data of 1996-1997. The pH values in this case were close to 9. Our findings suggest that factors contributing to changing redox conditions, responsible for the formation of soda and abrupt increment of HCO3-, fluorine and aluminum concentrations, are time and temperature.

  15. Permeability Structure Beneath the Lost City Hydrothermal Field, Atlantis Massif Oceanic Core Complex

    NASA Astrophysics Data System (ADS)

    McCaig, A. M.; Titarenko, S.

    2012-12-01

    The Lost City Hydrothermal Field (LCHF) has been venting low temperature (50-90 C) alkaline fluids for at least 120,000 years. It is located close to the crest of the transform wall of the Atlantis Massif (30 N, MAR), and is underlain by detachment fault schists and serpentinized peridotites with minor gabbro. Only 5km to the north, IODP Hole 1309D sampled 1400 m of gabbroic rocks. An almost linear thermal gradient of ~100 C/km has recently been measured in the Hole during IODP expedition 340T, a unique piece of data in young ocean crust. The combination of a steep conductive gradient in proximity to a long lived hydrothermal system places severe constraints on the permeability structure of the Massif. We have used Comsol Multiphysics to create the first 2-D topographic model of the LCHF using a N-S profile through the vent site and Hole 1309D. Initial models use a constant basal heat flow (0.2 W/m2) which produces a steady state conductive gradient of about 85 C/km using temperature-dependent conductivity and heat capacity. We include a low permeability basal layer and in some models a lower permeability zone beneath the IODP Hole with a boundary dipping steeply southwards, corresponding to a boundary between gabbro and serpentinite inferred from seismic tomography. We have used two top boundary conditions; (1) a mixed boundary condition in which dT/dz =0 if flow is upwards, and T=0 if flow is downwards, and (2) T=0. The first boundary condition is normally used in hydrothermal modelling but produces serious vent temperature artifacts at low upward flow rates since heat cannot escape conductively. The second boundary condition produces more stable models and has been shown by Wilcock (1998) to reproduce the form of hydrothermal circulation accurately. However vent temperatures can only be approximated due to the upper thermal boundary layer produced. With a constant permeability in the upper part of the model, transient high temperature vents form near the highest point of the topography but migrate with time across the location of the borehole, where a conductive gradient is never established. Conditions in the Massif are much better reproduced by models with a lower permeability zone beneath the IODP borehole. This stabilises the vent location near the crest of the Massif, and creates a conductive gradient in the borehole which typically increases gradually with time up to about 400000 years. Transient high temperature venting (with unstable flow at permeabilities <10-15 m2) are succeeded by stable venting with gradually declining vent temperatures matching Lost City temperatures over significant time intervals. In all our models, seafloor topography strongly influences circulation with influx of fluid in the transform valley (where microbes could potentially live several km below the seafloor) and discharge in higher topography. The requirement of a particular permeability structure means that long-term vent sites similar to Lost City may be a relatively uncommon occurrence in the world's oceans.

  16. Rock avalanches on a glacier and morainic complex in Haut Val Ferret (Mont Blanc Massif, Italy)

    NASA Astrophysics Data System (ADS)

    Deline, Philip; Kirkbride, Martin P.

    2009-01-01

    Deposits in upper Val Ferret (Mont Blanc Massif, Italy) have been attributed to glacier advances and to a rock avalanche of 12 September AD 1717. We review evidence for the timing and mode of emplacement of the deposit, and present a new geomorphic interpretation and relative and absolute dating to show that the AD 1717 deposit is less extensive than previously thought. The landslide was deflected along one side of the valley floor, preserving older slope and morainic sediments along the other side. An earlier rock avalanche onto the Triolet Glacier occurred before AD 1000. The deposits of these landslides partly cover older moraine several kilometres downstream from the present glacier front, and have affected the glacier regimen and construction of its moraines. This study highlights the geomorphic impact of rock avalanches in glacierized high mountains.

  17. Sm-Nd dating of fluorite from the worldclass Montroc fluorite deposit, southern Massif Central, France

    USGS Publications Warehouse

    Munoz, M.; Premo, W.R.; Courjault-Rade, P.

    2005-01-01

    A three-point Sm-Nd isotope isochron on fluorite from the very large Montroc fluorite vein deposit (southern Massif Central, France) defines an age of 111??13 Ma. Initial ??Nd of -8.6 and initial 87Sr/86Sr of ???0.71245 suggest an upper crustal source of the hydrothermal system, in agreement with earlier work on fluid inclusions which indicated a basinal brine origin. The mid-Cretaceous age of ???111 Ma suggests the Albian/Aptian transition as the most likely period for large-scale fluid circulation during a regional extensional tectonic event, related to the opening of the North Atlantic ocean. ?? Springer-Verlag 2004.

  18. Crystal structure of hydrogen-bearing vuonnemite from the Lovozero alkaline massif

    SciTech Connect

    Rastsvetaeva, R. K. Aksenov, S. M.; Verin, I. A.; Lykova, I. S.

    2011-05-15

    Hydrogen-bearing vuonnemite from the Shkatulka hyperagpaitic pegmatite (the Lovozero alkaline massif, Kola Peninsula) was studied by single-crystal X-ray diffraction. The triclinic unit-cell parameters are as follows: a = 5.4712(1) Angstrom-Sign , b = 7.1626(1) Angstrom-Sign , c = 14.3702(3) Angstrom-Sign , {alpha} = 92.623(2) Degree-Sign , {beta} = 95.135(1) Degree-Sign , {gamma} = 90.440(1) Degree-Sign , sp. gr. P1, R = 3.4%. The Na{sup +} cations and H{sub 2}O molecules are ordered in sites between the packets. The water molecules are hydrogen bonded to the PO{sub 4} tetrahedra.

  19. Cancrinite from nepheline syenite (mariupolite) of the Oktiabrski massif, SE Ukraine, and its growth history.

    PubMed

    Dumańska-Słowik, Magdalena; Pieczka, Adam; Heflik, Wiesław; Sikorska, Magdalena

    2016-03-15

    Secondary cancrinite, (Na5.88K<0.01)∑5.88(Ca0.62 Fe0.01Mn0.01Zn<0.01 Mg<0.01)∑0.64[Si6.44Al 5.56O24](CO3)0.67(OH)0.26(F<0.01,Cl<0.01)·2.04H2O), was found as accessory component of mariupolite (albite-aegirine nepheline syenite) from the Oktiabrski massif in the Donbass (SE Ukraine). It probably crystallized from a subsolidus reaction involving nepheline (and sodalite?) and calcite dissolved in the aqueous-carbonic fluid at the maximum temperature of 930°C, decreasing to hydrothermal conditions. It is depleted in sodium, calcium and carbon, what results in the occurrence of vacant positions at both cationic and anionic sites. Ca-deficient cancrinite crystallized from the same hydrothermal Si-undersaturated fluids enriched in the ions such as Na(+), Ca(2+), Cl(-), F(-), HCO3(-), which formed calcite, sodalite, natrolite and fluorite. It has dark-red CL colours with patchy zoning, what indicates the variable/diverse fluid composition during its formation. In the CL spectrum of cancrinite only one broad emission band at 410nm is observed, which can be attributed to O* center (the recombination of a free electron with an O(-) hole center). The formation of secondary CO3-rich species, i.e. cancrinite and calcite in mariupolite suggests that redox conditions in the Oktiabrski massif were oxidizing at the postmagmatic stage. PMID:26773267

  20. Cancrinite from nepheline syenite (mariupolite) of the Oktiabrski massif, SE Ukraine, and its growth history

    NASA Astrophysics Data System (ADS)

    Dumańska-Słowik, Magdalena; Pieczka, Adam; Heflik, Wiesław; Sikorska, Magdalena

    2016-03-01

    Secondary cancrinite, (Na5.88K< 0.01)∑ 5.88(Ca0.62 Fe0.01Mn0.01Zn< 0.01 Mg< 0.01)∑ 0.64[Si6.44Al 5.56O24](CO3)0.67(OH)0.26(F< 0.01,Cl< 0.01)·2.04H2O), was found as accessory component of mariupolite (albite-aegirine nepheline syenite) from the Oktiabrski massif in the Donbass (SE Ukraine). It probably crystallized from a subsolidus reaction involving nepheline (and sodalite?) and calcite dissolved in the aqueous-carbonic fluid at the maximum temperature of 930 °C, decreasing to hydrothermal conditions. It is depleted in sodium, calcium and carbon, what results in the occurrence of vacant positions at both cationic and anionic sites. Ca-deficient cancrinite crystallized from the same hydrothermal Si-undersaturated fluids enriched in the ions such as Na+, Ca2 +, Cl-, F-, HCO3-, which formed calcite, sodalite, natrolite and fluorite. It has dark-red CL colours with patchy zoning, what indicates the variable/diverse fluid composition during its formation. In the CL spectrum of cancrinite only one broad emission band at 410 nm is observed, which can be attributed to O* center (the recombination of a free electron with an O- hole center). The formation of secondary CO3-rich species, i.e. cancrinite and calcite in mariupolite suggests that redox conditions in the Oktiabrski massif were oxidizing at the postmagmatic stage.

  1. Petrology of low pressure granulites from the Lichtenberg and Sauwald zone, Bohemian Massif, Upper Austria

    NASA Astrophysics Data System (ADS)

    Sorger, Dominik; Daghighi, Donia; Simic, Katica; Hauzenberger, Christoph; Linner, Manfred; Fritz, Harald

    2013-04-01

    The Bohemian Massif in Upper Austria exposes low pressure granulite facies rocks which belong to the Moldanubian Unit and were metamorphosed during the last stage of the Variscan orogeny. The investigated Lichtenberg (northwest of Linz) and Sauwald (south of the river Danube) zones comprise mainly paragneisses. However, most of these rocks underwent high degrees of melting forming meta- and diatexites ("Perlgneise"). Al-rich metapelites, which are suitable for precise PT and PT-path determinations, can be found in various localities throughout the whole unit. In this study samples from the cliffs along the Danube valley between Linz and Wilhering and from Werndorf (close to Schrding) were sampled and investigated petrographically in detail. Since garnets are rare and usually consumed by cordierite, a sample with unusual large garnets was of special interest. A chemical zoning profile across the diameter of the c. 1cm large garnet showed an elevated Ca-plateau (Xgrs=0.06) in the core which decreased discontinuously towards the rim to Xgrs=0.02. Almandine, pyrope and spessartine components do not show any pronounced zoning pattern. Most of the smaller garnet grains in other samples are also homogeneous in composition with a slight Xalm increase and Xprp decrease at the rims, typical for retrograde diffusional zoning. The migmatic gneisses and cordierite-garnet-sillimanite-granulites as well as mafic granulites were used for geothermobarometric calculations. Metamorphic conditions of around 770C to 850C and 0.5-0.6 GPa could be obtained, which are similar to the values obtained by Tropper et al. (2006). P. Tropper I. Deibl F. Finger R. Kaindl (2006). P-T-t evolution of spinel-cordierite-garnet gneisses from the Sauwald Zone (Southern Bohemian Massif, Upper Austria): is there evidence for two independent late-Variscan low-P / high-T events in the Moldanubian Unit? Int J Earth Sci (Geol Rundsch) (2006) 95: 1019-1037.

  2. Origin of mafic and ultramafic cumulates from the Ditrău Alkaline Massif, Romania

    NASA Astrophysics Data System (ADS)

    Pál-Molnár, Elemér; Batki, Anikó; Almási, Enikő; Kiss, Balázs; Upton, Brian G. J.; Markl, Gregor; Odling, Nicholas; Harangi, Szabolcs

    2015-12-01

    Mafic-ultramafic cumulates enclosed in gabbroic-dioritic rocks form part of the Mesozoic Ditrău Alkaline Massif in the Eastern Carpathians, Romania. The poikilitic olivine- and pyroxene-rich and nearly mono mineralic hornblendite rocks display typical cumulate textures with early crystallised olivine (Fo75-73), diopside and augite. In the early stages of their genesis the amphibole was intercumulus whilst in later stages it acquired cumulus status as the fractionating magma evolved. Using major and trace element compositions of minerals and whole-rock samples the origin of these cumulates is determined and the parental magma composition and depth of emplacement are calculated. Cumulus clinopyroxene has more primitive composition than intercumulus amphibole suggesting closed system fractionation for the evolution of poikilitic olivine- and pyroxene-rich cumulates. The evolution of the amphibole-rich mesocumulates is more clearly the result of closed system crystallisation dominated by the precipitation of clinopyroxene and amphibole cumulus crystals. Lamprophyre dykes of the Ditrău Alkaline Massif are proposed to reflect multiple basanitic parental magma batches from which the cumulus olivine and clinopyroxene crystallised. Relative to these dykes the calculated equilibrium melts for intercumulus amphibole in the cumulates was more primitive whilst that for the cumulus amphibole was more evolved. The calculated crystallisation temperature and pressure of ~ 1000-1050 °C and ~ 0.7 GPa, based on the composition of the amphiboles, indicate crystallisation at lower crustal depths. Rare earth element compositions are consistent with an intra-plate tectonic setting.

  3. Cenozoic denudation of the Menderes Massif and its geodynamic framework: slab tear or not?

    NASA Astrophysics Data System (ADS)

    Gessner, Klaus; Gallardo, Luis; Markwitz, Vanessa; Ring, Uwe; Thomson, Stuart

    2014-05-01

    Despite having experienced similar rates of convergence during the Alpine Orogeny, the Hellenides and Anatolides display fundamental differences in crust and mantle structure across a region that broadly coincides with the Aegean coastline of the Anatolian peninsula. The Menderes Massif experienced early Miocene tectonic denudation and surface uplift in the footwall of a north-directed extensional detachment system, followed by late Miocene to recent fragmentation by E-W and NW-SE trending graben systems, resulting in one of Earth's largest metamorphic core complexes. Based on the interpretation of geological and geophysical data we propose that the tectonic denudation of the Menderes Massif was caused by late Oligocene/early Miocene lithosphere scale transtension along the boundary of the Adriatic and Anatolian lithospheric domains, when rollback of the Aegean slab affected the Aegean-Menderes section of the Tethyan Orogen. In addition to previously hypothesized crustal discontinuities, gravity data, earthquake locations and seismic velocity anomalies highlight a north-south oriented boundary in the upper mantle between a fast slab below the Aegean and a slow asthenospheric region below western Turkey. As an alternative to the common interpretation of this discontinuity representing the western edge of a slab tear, we propose that the change in lithospheric structure is the result of how different lithosphere domains responded to roll-back: relatively slow removal of lithospheric mantle below western Anatolia versus trench retreat in the rapidly extending Aegean Sea region. Our findings highlight the significance of lateral variations in subduction-collision systems for the formation of continental plateaux and metamorphic core complexes.

  4. Homogeneous /sup 18/O enrichment of the Marcy Anorthosite Massif, Adirondack Mountains, New York

    SciTech Connect

    Morrison, J.; Valley, J.W.

    1985-01-01

    The Marcy Anorthosite Massif in the Adirondack Mountains, New York, is a composite intrusion that was metamorphosed to granulite facies at approx. 1.1 Ga. The massif is dominantly anorthosite but ranges from anorthosite (1-10% mafics) to oxide-rich pyroxenite layers (up to 98% mafics). In the St Regis Quad (SRQ) systematic variations in the percentage of mafics (POM) roughly parallel the foliation and increase toward the contacts (Davis, 1971). In 47 SRQ samples studied the POM varies from 2-25%; garnet ranges from 0-11%, pyroxene from <1-16% and oxides from <1-8%. Percent phenocrysts varies between 1-80. The Port Kent-Westport Unit (PKW) and an associated hybrid unit show significantly greater textural variability. The POM Varies from 1-50%; garnet ranges from 0-18%, pyroxene from 0-15%, oxides from 0-3% and phenocrysts vary from 0-80%. A total of 28 unaltered plagioclase phenocrysts have been analyzed for delta/sup 18/O: in 13 SRQ samples delta/sup 18/O = 9.0-9.8 (x=9.4. sigma=0.2) and in 15 samples from the PKW and hybrid units values of delta/sup 18/O=8.5-10.5 (x=9.5.sigma0.5). No correlations exist between the modal parameters and delta/sup 18/O. The results from SRQ demonstrate an extreme homogeneity suggesting for the first time a pristine magmatic character which is supported by the virtual absence of metasedimentary inclusions. This contrasts with PKW where inclusions are common and delta/sup 18/O values are more heterogeneous. Further analyses will evaluate the possibility of an anomalous source region as a cause of the /sup 18/O enrichment in the anorthosite.

  5. Proterozoic massif anorthosites and related rocks in Labrador: the anorthosite-charnockite connection

    SciTech Connect

    Emslie, R.F.

    1985-01-01

    Massif anorthosites of Labrador are closely associated in space and time with voluminous, felsic, fayalite- and ferrous pyroxene-bearing igneous rocks. These include charnockites, monzonites, biotite-hornblende granites, and locally syenites. Igneous charnockites form major parts of some of the granitic complexes. In Mistastin batholith for example, charnockitic assemblages comprise about 35% of a total area of 6500 sq. km. Feldspar pairs and coexisting fayalite-opx-qtz in these rocks indicate P and T near 3.5 kb, 750/sup 0/C, assumed to represent near solidus equilibration. Diorites and monzonites intruded by charnockite have mesoperthites implying crystallization T>900/sup 0/C presumably recording earlier stages of crystallization. Oxide and silicate assemblages indicate redox conditions between FMQ and WM oxygen buffers and water pressures well below Ptotal. Younger biotite-hornblende granites and quartz syenites lack Ti-mt. but retain fayalite suggesting that magmatic crystallization was largely closed to water and oxygen. Initial Sr isotope ratios in charnockite-granite suites of central labrador support derivation of the magmas largely or entirely from crustal source rocks. Compositions of mafic silicates and plagioclase, associated Fe-Ti oxide concentrations, trace elements and Sr isotopes in massif anorthosites are in accord with the rocks being crystallization products of substantially fractionated, originally more mafic, mantle magmas. Close association of high temperature, water-poor, reduced crustal melts is consistent with a fusion process in which heat supply and oxygen buffering were controlled by fractional crystallization of a substantial body of mafic magma subjacent to continental crust.

  6. The cooling history and the depth of detachment faulting at the Atlantis Massif oceanic core complex

    NASA Astrophysics Data System (ADS)

    Schoolmeesters, Nicole; Cheadle, Michael J.; John, Barbara E.; Reiners, Peter W.; Gee, Jeffrey; Grimes, Craig B.

    2012-10-01

    Oceanic core complexes (OCCs) are domal exposures of oceanic crust and mantle interpreted to be denuded to the seafloor by large slip oceanic detachment faults. We combine previously reported U-Pb zircon crystallization ages with (U-Th)/He zircon thermochronometry and multicomponent magnetic remanence data to determine the cooling history of the footwall to the Atlantis Massif OCC (30N, MAR) and help establish cooling rates, as well as depths of detachment faulting and gabbro emplacement. We present nine new (U-Th)/He zircon ages for samples from IODP Hole U1309D ranging from 40 to 1415 m below seafloor. These data paired with U-Pb zircon ages and magnetic remanence data constrain cooling rates of gabbroic rocks from the upper 800 m of the central dome at Atlantis Massif as 2895 (+1276/-1162) C Myr-1 (from 780C to 250C); the lower 600 m of the borehole cooled more slowly at mean rates of 500 (+125/-102) C Myr-1(from 780C to present-day temperatures). Rocks from the uppermost part of the hole also reveal a brief period of slow cooling at rates of 300C Myr-1, possibly due to hydrothermal circulation to 4 km depth through the detachment fault zone. Assuming a fault slip rate of 20 mm/yr (from U-Pb zircon ages of surface samples) and a rolling hinge model for the sub-surface fault geometry, we predict that the 780C isotherm lies at 7 km below the axial valley floor, likely corresponding both to the depth at which the semi-brittle detachment fault roots and the probable upper limit of significant gabbro emplacement.

  7. Diamonds Discovered in Five Peridotite Massifs Along the Yarlung-Zangbo Suture in South Tibet: Tectonic Implications

    NASA Astrophysics Data System (ADS)

    Xu, X.; Yang, J.; Ba, D.; Li, Y.; Zhao, L.; Robinson, P. T.

    2011-12-01

    Many ophiolitic peridotite massifs occur along the more than 1500-km-long Yarlung-Zangbo suture in south Tibet, which marks the boundary between the Indian and Eurasian plates after closure of Neo-Tethys at about 55 Ma. Some of the massifs are very large, e.g., the Xigaze massif (ca. 700 km2) in the middle segment, and the Purang (ca. 600 km2) and Dongbo (ca. 400 km2) massifs in the western segment of the suture. In-situ diamonds and moissanite, along with many unusual, highly reduced minerals, such as native Fe, Cr, Ni and metal alloys have been previously reported from chromitites and peridotites of the Luobusa ophiolitic massif in the eastern segment of the suture. Coesite pseudomorphing stishovite from the Luobusa chromitite suggests depths of formation >300 km. Here we present the first report of diamonds and other unusual minerals in four other peridotite bodies along the Yarlung-Zangbo suture, namely from east to west, the Xigaze, Dangqiong, Purang and Dongbo massifs. These massifs consist mainly of harzburgite, lherzolite and dunite, probably of MOR type, that were modified in a SSZ environment. Several tens of diamonds and some unusual minerals such as moissanite were recovered by standard mineral separation techniques from individual samples ranging from 300 to 600 kg in weight. The diamonds are yellowish-green in color, about 0.1-0.3 mm in size, and have octahedral and cone-like forms. These diamonds are similar to those found in the Luobusa massif, and commonly contain inclusions of Ni-Mn-Co alloys, a feature that distinguishes them from kimberlitic and metamorphic diamonds. Textural evidence and Ca-K-Cl fluid inclusions indicate that they grew from C-rich fluids. Fifty analyses of diamonds from the Yarlung-Zangbo suture yielded δ13CPDB values ranging from -18.3 % to -28.7%, with an average of -24.6%. There are no statistical differences in the isotopic composition among diamonds from the different localities or among those occurring in chromitite or harzburgite. The fluids from which the diamonds crystallized must have been derived from a carbon source distinctly different from that of typical kimberlitic diamonds, most of which have δ13CPDB values of -1% to -8%. The widespread occurrence of UHP minerals in the Yarlung-Zangbo ophiolites demonstrates that the Luobusa ophiolite is not a unique diamond-bearing massif, and that there exists a major new occurrence of diamonds in the oceanic mantle, unrelated to kimberlites and UHP metamorphism. Previous work suggests that both the diamonds and chromitites of Luobusa crystallized in the diamond stability field at depths greater than ~150 km, possibly deeper than 300 km, thus raising questions regarding the current models for the formation of ophiolites and podiform chromitites. It is possible that the diamonds formed from C-rich fluids with highly reduced phases and low δ13CPDB values derived from the deep mantle.

  8. 76 FR 1146 - Notice of Intent To Prepare an Environmental Assessment for the Proposed Northeast Supply...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-07

    ... Northeast Supply Diversification Project and Ellisburg to Craigs Project, and Request for Comments on...). TGP's Northeast Supply Diversification Project would involve construction and operation of facilities... and compressor station, and other appurtenant facilities. The Northeast Supply Diversification...

  9. Volcanic evolution of the submarine super volcano, Tamu Massif of Shatsky Rise: New insights from Formation MicroScanner logging imagery

    NASA Astrophysics Data System (ADS)

    Tominaga, Masako; Iturrino, Gerardo; Evans, Helen F.

    2015-01-01

    Massif, the southernmost plateau of Shatsky Rise, is recently reported as the largest single volcano known on Earth. This work seeks to understand the type of volcanism necessary to form such an anomalously large single volcano by integrating core and high-resolution wireline logging data. In particular, resistivity imagery obtained by the Formation MicroScanner, in Integrated Ocean Drilling Program Hole U1347A, located on the eastern flank of Tamu Massif, was used to construct a logging-based volcanostratigraphy. This model revealed two different volcanic stages formed Tamu Massif: (i) the core part of the massif's basaltic basement was formed by a "construction phase" of volcanism with cyclic eruption events from a steady state magma supply and (ii) the very topmost basaltic section was formed by a "depositional phase" of volcanism during which long-traveling lava flows were deposited from a distant eruption center.

  10. Algorithm of Rock Burst Preparation Scenario Construction in Rock Massif under Explosion Influence using seismic Catalogue Data

    NASA Astrophysics Data System (ADS)

    Hachay, Olga; Khachay, Oleg; Klimko, Valeriy; Shipeev, Oleg

    2014-05-01

    A new algorithm of seismological information processing of detailed mines catalogue with use kinematic and dynamical characteristics of deformation waves, which propagate with different velocities in the rock massif, which is under heavy influence of single blasts and technological explosions is developed. It is estimated that the waves, which propagate with the velocities from 10 to 1 m/hour are primary carrier of the energy in the massif and promote its releasing. Events, which occur in the massive with these waves with releasing energy less than 104 joules promote to the creep rebuilding of the massif. Events, which occur in the massive with these waves with releasing energy more, than 105 joules, can be used as rock burst precursory and it is recommend taking into account by changing of explosions in the indicated part of the massif. The whole absence of such events indicates the growing of the stress massif state in the mine as a whole. The received joined information from the seismic catalogue is very significant for forecasting of dangerous events in the rock mines. That algorithm can be used also for analyzing seismic natural events preparation. Key words: massif response, slow deformation waves, seismic mine catalogue, analyze of observed data, algorithm of seismological information processing. 1.Hachay O. A. The reflection of synergetic Features in the Response of geological Medium on outer Force Actions. / O. A. Hachay, O. Yu. Khachay, V. K. Klimko, O. Yu. Shipeev // Advances in heterogeneous Material Mechanics - Shanghai, China, 2011. -P. 361-366. 2.Hachay O. A. Construction of a State Evolution dynamical Model of a Rock Massive, which is in a regime of energetic Pumping. / O. A. Hachay, A. Yu. Khachay, O. Yu. Khachay // Geophysical Research abstracts. -2011, -Vol. 13, - EGU2011 - 1528. 3.Khachay O.A. Dynamical model for evolution of Rock Massive State as a Response on a Changing of Stress-Deformed State. / O. A. Hachay, A. Yu. Khachay, O. Yu. Khachay //Fractal analysis and Chaos in Geosciences, chapter 5./Edited by Sid-Ali Quadfeul. -In Tech,Croatia. 2012. -174p.

  11. Subcontinental rift initiation and ocean-continent transitional setting of the Dinarides and Vardar zone: Evidence from the Krivaja-Konjuh Massif, Bosnia and Herzegovina

    NASA Astrophysics Data System (ADS)

    Faul, Ulrich H.; Garapi?, Gordana; Lugovi?, Boko

    2014-08-01

    The Dinaride and Vardar zone ophiolite belts extend from the south-eastern margins of the Alps to the Albanian and Greek ophiolites. Detailed sampling of the Krivaja-Konjuh massif, one of the largest massifs in the Dinaride belt, reveals fertile compositions and an extensive record of deformation at spinel peridotite facies conditions. High Na2O clinopyroxene and spinel-orthopyroxene symplectites after garnet indicate a relatively high pressure, subcontinental origin of the southern and western part of Krivaja, similar to orogenic massifs such as Lherz, Ronda and the Eastern Central Alpine peridotites. Clinopyroxene and spinel compositions from Konjuh show similarities with fertile abyssal peridotite. In the central parts of the massif the spinel lherzolites contain locally abundant patches of plagioclase, indicating impregnation by melt. The migrating melt was orthopyroxene undersaturated, locally converting the peridotites to massive olivine-rich troctolites. Massive gabbros and more evolved gabbro veins cross-cutting peridotites indicate continued melt production at depth. Overall we infer that the massif represents the onset of rifting and early stages of formation of a new ocean basin. In the south of Krivaja very localized chromitite occurrences indicate that much more depleted melts with supra-subduction affinity traversed the massif that have no genetic relationship with the peridotites. This indicates that volcanics with supra-subduction affinity at the margins of the Krivaja-Konjuh massif record separate processes during closure of the ocean basin. Comparison with published compositional data from other Balkan massifs shows that the range of compositions within the Krivaja-Konjuh massif is similar to the compositional range of the western massifs of the Dinarides. The compositions of the Balkan massifs show a west to east gradient, ranging from subcontinental on the western side of the Dinarides to depleted mid-ocean ridge/arc compositions in the Vardar zone in the east. This is consistent with the hypothesis that both ophiolite belts originate in a single ocean, rather than from two separate basins. A distinct decrease in fertility occurs in the south of the Dinarides towards the Albanian ophiolites with supra-subduction affinity.

  12. Destabilization of the Northeast Greenland Ice Stream

    NASA Astrophysics Data System (ADS)

    Korsgaard, N. J.; Khan, S. A.; Kjaer, K.; Bevis, M. G.; Bamber, J. L.; Kjeldsen, K. K.; Bjork, A. A.; Wahr, J. M.; Stearns, L. A.; van den Broeke, M. R.; Muresan, I. S.; Larsen, N. K.

    2013-12-01

    The Greenland Ice Sheet (GrIS) has been one of the largest contributors to global sea level rise over the last 20 years, accounting for c. 0.5 of a total of c. 3.2 mm yr-1. A significant portion of this contribution is associated with the speed up of glaciers in southeast and northwest Greenland. Here, we reveal that the Northeast Greenland Ice Stream (NEGIS), which extends more than 600 km into the interior of the ice sheet, is now undergoing dynamic thinning after more than a quarter of a century of stability. This sector of the GrIS is of particular interest in sea level projections, because the glacier flows into a large submarine basin with a negative bed slope near the grounding line. Our findings unfold the next step in mass loss of the GrIS as we show a heightened risk of rapid sustained loss from Northeast Greenland on top of the thinning in Southeast and Northwestern Greenland.

  13. NASA Northeast Regional Technology Transfer Center

    NASA Technical Reports Server (NTRS)

    Dunn, James P.

    2001-01-01

    This report is a summary of the primary activities and metrics for the NASA Northeast Regional Technology Transfer Center, operated by the Center for Technology Commercialization, Inc. (CTC). This report covers the contract period January 1, 2000 - March 31, 2001. This report includes a summary of the overall CTC Metrics, a summary of the Major Outreach Events, an overview of the NASA Business Outreach Program, a summary of the Activities and Results of the Technology into the Zone program, and a Summary of the Major Activities and Initiatives performed by CTC in supporting this contract. Between January 1, 2000 and March 31, 2001, CTC has facilitated 10 license agreements, established 35 partnerships, provided assistance 517 times to companies, and performed 593 outreach activities including participation in 57 outreach events. CTC also assisted Goddard in executing a successful 'Technology into the Zone' program.' CTC is pleased to have performed this contract, and looks forward to continue providing their specialized services in support of the new 5 year RTTC Contract for the Northeast region.

  14. Northeast Oregon Hatchery Project, Final Siting Report.

    SciTech Connect

    Watson, Montgomery

    1995-03-01

    This report presents the results of site analysis for the Bonneville Power Administration Northeast Oregon Hatchery Project. The purpose of this project is to provide engineering services for the siting and conceptual design of hatchery facilities for the Bonneville Power Administration. The hatchery project consists of artificial production facilities for salmon and steelhead to enhance production in three adjacent tributaries to the Columbia River in northeast Oregon: the Grande Ronde, Walla Walla, and Imnaha River drainage basins. Facilities identified in the master plan include adult capture and holding facilities; spawning incubation, and early rearing facilities; full-term rearing facilities; and direct release or acclimation facilities. The evaluation includes consideration of a main production facility for one or more of the basins or several smaller satellite production facilities to be located within major subbasins. The historic and current distribution of spring and fall chinook salmon and steelhead was summarized for the Columbia River tributaries. Current and future production and release objectives were reviewed. Among the three tributaries, forty seven sites were evaluated and compared to facility requirements for water and space. Site screening was conducted to identify the sites with the most potential for facility development. Alternative sites were selected for conceptual design of each facility type. A proposed program for adult holding facilities, final rearing/acclimation, and direct release facilities was developed.

  15. 10. INTERIOR, NORTHEAST STORAGE AREA, FROM APPROXIMATELY 15 FEET SOUTHWEST ...

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

    10. INTERIOR, NORTHEAST STORAGE AREA, FROM APPROXIMATELY 15 FEET SOUTHWEST OF NORTHEAST CORNER, LOOKING WEST-SOUTHWEST, WITH CONNECTING DOORWAYS IN FAR WALL. - Oakland Naval Supply Center, Pier Transit Shed, South of D Street between First & Second Streets, Oakland, Alameda County, CA

  16. Understanding Philanthropic Motivations of Northeast State Community College Donors

    ERIC Educational Resources Information Center

    Cook, Heather J.

    2012-01-01

    At Northeast State Community College (NeSCC) nearly 70% of students need some form of financial aid to attend. State support is flattening or decreasing and the gap is filled by private donors' support (Northeast State Community College, 2011). Hundreds of donors have made significant contributions to aid in the education of those in the…

  17. 4. View to northwest showing southeast and northeast elevations of ...

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

    4. View to northwest showing southeast and northeast elevations of 1909 SE wing, with 1941 SE wing and porte-cochere (at left), and original front facade (northeast elevation) at right - Portsmouth Naval Hospital, Hospital Building, Rixey Place, bounded by Williamson Drive, Holcomb Road, & The Circle, Portsmouth, Portsmouth, VA

  18. 2. View of blast deflector fences along northeast side of ...

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

    2. View of blast deflector fences along northeast side of the operational apron. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Blast Deflector Fences, Northeast & Southwest sides of Operational Apron, Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  19. 5. Northeast rear and northwest end, building no. 529. View ...

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

    5. Northeast rear and northwest end, building no. 529. View to south. - Offutt Air Force Base, Looking Glass Airborne Command Post, Hydraulic Fluid Buildings, Northeast of Looking Glass Avenue at southwest side of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  20. 3. Northeast rear and northwest end, building no. 528. View ...

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

    3. Northeast rear and northwest end, building no. 528. View to south. - Offutt Air Force Base, Looking Glass Airborne Command Post, Hydraulic Fluid Buildings, Northeast of Looking Glass Avenue at southwest side of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  1. 2. Southeast end and northeast rear, building no. 528. View ...

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

    2. Southeast end and northeast rear, building no. 528. View to west. - Offutt Air Force Base, Looking Glass Airborne Command Post, Hydraulic Fluid Buildings, Northeast of Looking Glass Avenue at southwest side of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  2. The northeast water supply crisis of the 1960's

    USGS Publications Warehouse

    Barksdale, Henry C.

    1968-01-01

    The water supply drought in the Northeast began in the autumn of 1961 and marked the beginning of a severe water shortage that continued with little relief through the summer of 1966. During this time, throughout much of the Northeast, water supplies remained below normal.

  3. 78 FR 23815 - Northeast Corridor Safety Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-22

    ... Committee is chartered by the Secretary of Transportation and is an official Federal Advisory Committee... Northeast Corridor, and the purpose of the Committee is to provide annual recommendations to the Secretary... the Secretary, Northeast Corridor train inspection and testing, and a general discussion of...

  4. 1. ROCKET ENGINE TEST STAND, LOCATED IN THE NORTHEAST ¼ ...

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

    1. ROCKET ENGINE TEST STAND, LOCATED IN THE NORTHEAST ¼ OF THE X-15 ENGINE TEST COMPLEX. Looking northeast. - Edwards Air Force Base, X-15 Engine Test Complex, Rocket Engine & Complete X-15 Vehicle Test Stands, Rogers Dry Lake, east of runway between North Base & South Base, Boron, Kern County, CA

  5. 7 CFR 1001.2 - Northeast marketing area.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Northeast marketing area. 1001.2 Section 1001.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order...

  6. 16. View of northeast corner of East Ward Street and ...

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

    16. View of northeast corner of East Ward Street and North McDonald Avenue, facing northeast. - Gaskin Avenue Neighborhood, Bounded by Dart Street to east, CSX Railroad to south, Pearl & Madison Avenues to west, & Wilson & Gordon Streets to north, Douglas, Coffee County, GA

  7. 5. VIEW OF FRONT (WEST AND SOUTH SIDES) TO NORTHEAST. ...

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

    5. VIEW OF FRONT (WEST AND SOUTH SIDES) TO NORTHEAST. VIEW TO NORTHEAST. NOTE THAT LARGE TREES PREVENT MORE COMPLETE VIEW FROM BETTER ANGLE. FOR MORE COMPLETE VIEW, SEE PHOTOGRAPHIC COPY OF 1916 PHOTO, NO. ID-17-C-35. - Boise Project, Boise Project Office, 214 Broadway, Boise, Ada County, ID

  8. 27. LOBBY, LOOKING NORTHEAST FROM SECOND FLOOR. THE STRUCTURE IN ...

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

    27. LOBBY, LOOKING NORTHEAST FROM SECOND FLOOR. THE STRUCTURE IN UPPER LEFT HAND SIDE OF PHOTOGRAPH, A MUSICIANS' PLATFORM CALLED 'THE CROW'S NEST' WAS BUILT IN THE GABLE. - Old Faithful Inn, 900' northeast of Snowlodge & 1050' west of Old Faithful Lodge, Lake, Teton County, WY

  9. 1. VIEW NORTHWEST, NORTHEAST SIDE AND SOUTHEAST FRONT OF TOWER ...

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

    1. VIEW NORTHWEST, NORTHEAST SIDE AND SOUTHEAST FRONT OF TOWER AND ORIGINAL LIGHTHOUSE - Mispillion Lighthouse, Beacon Tower, South bank of Mispillion River at it confluence with Delaware River at northeast end of County Road 203, 7 miles east of Milford, Milford, Sussex County, DE

  10. NORTHEAST LOON STUDY WORKING GROUP PARTNERSHIP TO ASSESS ENVIRONMENTAL RISK

    EPA Science Inventory

    The Northeast Loon Study Working Group (NELSWG) was formed in 1994 to proactively identify threats to one of the Northeast's most popular waterbirds, the common loon, Gavia immer. Seventeen institutions have come together to identify strategy, coordinate the work load, and share ...

  11. 17. Interior detail, pilaster on transverse wall at the northeast ...

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

    17. Interior detail, pilaster on transverse wall at the northeast end of the Machine Shop, Roundhouse Machine Shop Extension, Southern Pacific Railroad Carlin Shops, view to northeast (90mm lens). Note the offset top of the pilaster, a feature common to all interior transverse wall pilasters. - Southern Pacific Railroad, Carlin Shops, Roundhouse Machine Shop Extension, Foot of Sixth Street, Carlin, Elko County, NV

  12. 7 CFR 1001.2 - Northeast marketing area.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Northeast marketing area. 1001.2 Section 1001.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order...

  13. 7 CFR 1001.2 - Northeast marketing area.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Northeast marketing area. 1001.2 Section 1001.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order...

  14. 7 CFR 1001.2 - Northeast marketing area.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Northeast marketing area. 1001.2 Section 1001.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order...

  15. 27. NORTHEAST TO TWO CIRCA 1900 DRILL PRESSES (LEFT TO ...

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

    27. NORTHEAST TO TWO CIRCA 1900 DRILL PRESSES (LEFT TO RIGHT MADE BY W. F. AND J. BARNES CO., ROCKFORD, ILL., AND CHAMPION BLOWER AND FORGE CO., LANCASTER, PENN.) AND BLACKSMITH SHOP AREA ALONG EAST INTERIOR WALL AT NORTHEAST CORNER OF FACTORY BUILDING. - Kregel Windmill Company Factory, 1416 Central Avenue, Nebraska City, Otoe County, NE

  16. View of parade ground inside fort looking to the northeast ...

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

    View of parade ground inside fort looking to the northeast generally so that part of the north wall is visible as well as the first 8 bays of the northeast wall (note: cannon in foreground and shadow of flagpole above gorge wall) - Fort Pulaski, Cockspur Island, Savannah, Chatham County, GA

  17. 2. SOUTHEAST SIDE AND NORTHEAST REAR. SHOP BUILDING IN DISTANCE. ...

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

    2. SOUTHEAST SIDE AND NORTHEAST REAR. SHOP BUILDING IN DISTANCE. NOTE CONCRETE PROTECTION SLAB FOR UNDERGROUND CONTROL ROOM AND ESCAPE HATCH ON GROUND AT RIGHT MIDDLE DISTANCE. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Firing Control Building, Test Area 1-100, northeast end of Test Area 1-100 Road, Boron, Kern County, CA

  18. 3. NORTHEAST REAR, SHOWING CONCRETE ENCASEMENT FOR STAIRWAY LEADING FROM ...

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

    3. NORTHEAST REAR, SHOWING CONCRETE ENCASEMENT FOR STAIRWAY LEADING FROM INSTRUMENT ROOM TO UNDERGROUND FIRING CONTROL ROOM. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Firing Control Building, Test Area 1-100, northeast end of Test Area 1-100 Road, Boron, Kern County, CA

  19. 7 CFR 1001.2 - Northeast marketing area.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Northeast marketing area. 1001.2 Section 1001.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order...

  20. 72. NORTHEAST SIDE OF NITROGEN EXCHANGERS IN FOREGROUND; FUEL APRON ...

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

    72. NORTHEAST SIDE OF NITROGEN EXCHANGERS IN FOREGROUND; FUEL APRON IN BACKGROUND. NORTHEAST CORNER OF WEST CAMERA TOWER ALSO IN BACKGROUND. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  1. REGIONAL OXIDANT MODELING OF THE NORTHEAST U.S.

    EPA Science Inventory

    The occurrence of long range and interurban transport of ozone and/or ozone precursors across the Northeast U.S. has been documented by numerous field studies during the last ten years. The U.S. Environmental Protection Agency initiated the Northeast Corridor Regional Modeling Pr...

  2. 33 CFR 117.829 - Northeast Cape Fear River.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Northeast Cape Fear River. 117.829 Section 117.829 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements North Carolina § 117.829 Northeast Cape Fear River. (a) The draw of the Isabel S....

  3. Trestle #1, wing wall on northwest side of northeast abutment. ...

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

    Trestle #1, wing wall on northwest side of northeast abutment. View to northeast - Promontory Route Railroad Trestles, S.P. Trestle 779.91, One mile southwest of junction of State Highway 83 and Blue Creek, Corinne, Box Elder County, UT

  4. 2. VIEW OF NORTHEAST (GABLE END) AND SOUTHEAST SIDES FROM ...

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

    2. VIEW OF NORTHEAST (GABLE END) AND SOUTHEAST SIDES FROM THE NORTHEAST. (BUILDING 111 VISIBLE ON LEFT; BUILDING 114 AT RIGHT.) INTERIOR OF BUILDING 113 TO THE SOUTHEAST.) - Fort McPherson, World War II Station Hospital, G. U. Treatment Unit Lavatory, Thorne & Hood Avenues, Atlanta, Fulton County, GA

  5. Cell block three and northeast guard tower (center), looking from ...

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

    Cell block three and northeast guard tower (center), looking from the central guard tower, facing northeast (note view also includes the baseball field (left), and cell blocks fourteen and eleven (right)) - Eastern State Penitentiary, 2125 Fairmount Avenue, Philadelphia, Philadelphia County, PA

  6. Understanding Philanthropic Motivations of Northeast State Community College Donors

    ERIC Educational Resources Information Center

    Cook, Heather J.

    2012-01-01

    At Northeast State Community College (NeSCC) nearly 70% of students need some form of financial aid to attend. State support is flattening or decreasing and the gap is filled by private donors' support (Northeast State Community College, 2011). Hundreds of donors have made significant contributions to aid in the education of those in the

  7. 7. Credit BG. View looking northeast at observation booth on ...

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

    7. Credit BG. View looking northeast at observation booth on northeast corner of Control and Recording Center. Test Stand 'D' complex appears at left of image. - Jet Propulsion Laboratory Edwards Facility, Control & Recording Center, Edwards Air Force Base, Boron, Kern County, CA

  8. Pleistocene geomorphological and sedimentary development of the Akaki River catchment (northeastern Troodos Massif) in relation to tectonic uplift versus climatic change

    NASA Astrophysics Data System (ADS)

    Main, Charlotte E.; Robertson, Alastair H. F.; Palamakumbura, Romesh N.

    2016-01-01

    The uplift of the Troodos ophiolite is reflected in the development of the Akaki River catchment in the northeast Troodos Massif. Four main stages (F1-F4) of geomorphological terrace development and related deposits are recognised using satellite imagery and field observations. The geomorphological terraces have been tectonically uplifted during the Pleistocene so that they dip northwards from the Troodos Mountains until they merge with the Mesaoria Plain. Lithology (e.g. hard diabase versus soft extrusive rock) has exerted an important control on the geomorphology of the Akaki River channel. The F1 terraces and related deposits are well preserved in the lower reaches of the catchment. The F2 terraces are more widely preserved but with few preserved deposits. The F3 erosional surfaces (e.g. strath terraces) and related deposits are widespread up into the higher reaches of the catchment. The F4 to recent geomorphological surfaces and deposits are confined to near the modern river channel. The F1- to F3-aged deposits each include very high-energy mass-flow deposits and somewhat lower-energy traction-flow deposits, with minimal sand preservation. Stages of fluvial aggradation were followed by soil development (e.g. terra rossa). The F1- to F4-aged terraces and related deposits mainly formed in response to a combination of very long-term tectonic uplift and climatic-related change (long term and short term). Tectonic uplift was the dominant driver related to the updoming of the Troodos ophiolite, especially during the earlier time period (F1 and F2), whereas climate-related effects appear to have dominated more recently (F3 and F4). Sedimentary aggradation is likely to have predominated during interglacial periods, while interglacial-glacial transitions (when climate fluctuated) are seen as times of increased incision. Previous correlations of the F1-F4 fluvial deposits with similar deposits elsewhere in Cyprus, including coastal marine carbonate deposits, suggest that the F1 and F2 deposits are likely to be of Middle Pleistocene age and the F3-F4 deposits of Late Pleistocene to Holocene age.

  9. Pleistocene geomorphological and sedimentary development of the Akaki River catchment (northeastern Troodos Massif) in relation to tectonic uplift versus climatic change

    NASA Astrophysics Data System (ADS)

    Main, Charlotte E.; Robertson, Alastair H. F.; Palamakumbura, Romesh N.

    2015-10-01

    The uplift of the Troodos ophiolite is reflected in the development of the Akaki River catchment in the northeast Troodos Massif. Four main stages (F1-F4) of geomorphological terrace development and related deposits are recognised using satellite imagery and field observations. The geomorphological terraces have been tectonically uplifted during the Pleistocene so that they dip northwards from the Troodos Mountains until they merge with the Mesaoria Plain. Lithology (e.g. hard diabase versus soft extrusive rock) has exerted an important control on the geomorphology of the Akaki River channel. The F1 terraces and related deposits are well preserved in the lower reaches of the catchment. The F2 terraces are more widely preserved but with few preserved deposits. The F3 erosional surfaces (e.g. strath terraces) and related deposits are widespread up into the higher reaches of the catchment. The F4 to recent geomorphological surfaces and deposits are confined to near the modern river channel. The F1- to F3-aged deposits each include very high-energy mass-flow deposits and somewhat lower-energy traction-flow deposits, with minimal sand preservation. Stages of fluvial aggradation were followed by soil development (e.g. terra rossa). The F1- to F4-aged terraces and related deposits mainly formed in response to a combination of very long-term tectonic uplift and climatic-related change (long term and short term). Tectonic uplift was the dominant driver related to the updoming of the Troodos ophiolite, especially during the earlier time period (F1 and F2), whereas climate-related effects appear to have dominated more recently (F3 and F4). Sedimentary aggradation is likely to have predominated during interglacial periods, while interglacial-glacial transitions (when climate fluctuated) are seen as times of increased incision. Previous correlations of the F1-F4 fluvial deposits with similar deposits elsewhere in Cyprus, including coastal marine carbonate deposits, suggest that the F1 and F2 deposits are likely to be of Middle Pleistocene age and the F3-F4 deposits of Late Pleistocene to Holocene age.

  10. New insights into the history and origin of the southern Maya block, SE Mexico: U-Pb-SHRIMP zircon geochronology from metamorphic rocks of the Chiapas massif

    USGS Publications Warehouse

    Weber, Bodo; Iriondo, Alexander; Premo, Wayne R.; Hecht, Lutz; Schaaf, Peter

    2007-01-01

    The histories of the pre-Mesozoic landmasses in southern México and their connections with Laurentia, Gondwana, and among themselves are crucial for the understanding of the Late Paleozoic assembly of Pangea. The Permian igneous and metamorphic rocks from the Chiapas massif as part of the southern Maya block, México, were dated by U–Pb zircon geochronology employing the SHRIMP (sensitive high resolution ion microprobe) facility at Stanford University. The Chiapas massif is composed of deformed granitoids and orthogneisses with inliers of metasedimentary rocks. SHRIMP data from an anatectic orthogneiss demonstrate that the Chiapas massif was part of a Permian (∼ 272 Ma) active continental margin established on the Pacific margin of Gondwana after the Ouachita orogeny. Latest Permian (252–254 Ma) medium- to high-grade metamorphism and deformation affected the entire Chiapas massif, resulting in anatexis and intrusion of syntectonic granitoids. This unique orogenic event is interpreted as the result of compression due to flat subduction and accretionary tectonics. SHRIMP data of zircon cores from a metapelite from the NE Chiapas massif yielded a single Grenvillian source for sediments. The majority of the zircon cores from a para-amphibolite from the SE part of the massif yielded either 1.0–1.2 or 1.4–1.5 Ga sources, indicating provenance from South American Sunsás and Rondonian-San Ignacio provinces.

  11. Petrological Characterization of the Triassic Paleosurface in the Northern Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Yao, Kouakou; Thiry, Medard; Szuszkiewicz, Adam; Turniak, Krzysztof

    2010-05-01

    ‘Albitization' is a widespread alteration process affecting sedimentary, igneous and metamorphic rocks. Albitized facies usually show a pinkish to red colour, depending on the degree of alteration. The main mineralogical process of this phenomenon is the pseudomorphic replacement of the primary Ca-Na plagioclases by secondary albite (Na). During this replacement biotite is often transformed to chlorite and inclusions of hematite, apatite, titanite, and calcite develop. So far, albitization has been systematically regarded as caused by magmatic derived hydrothermal brines, alkaline metasomatism reactions (Cathelineau, 1986; Petersson and Eliasson, 1997), or as a low grade metamorphic facies (Boles and Coombs, 1977). Recent studies in the Morvan Massif granites (Ricordel et al., 2007; Parcerisa et al., 2009) showed that the albitization there is related to the Triassic paleosurface. The decrease of this alteration with depth and its paleomagnetic age support the link of the albitization to the Triassic paleosurface. Furthermore, the petrographic data suggest the import of sodium by weathering solutions. The enrichement in Na+ of the fluids that triggered this alteration is probably linked to the Triassic salt deposits. Albitised pinkish facies have been recognized in the northern part of the Bohemian Massif (Polish Sudetes). Typical igneous and metamorphic rocks of the Klodzko area (southern Poland) are granites, granodiorites, schists, amphibolite, and gneisses, mostly of Paleozoic age. Three sites in the Klodzko area were sampled in detail from N to S: (1) Laski quarry, (2) Laski village, and (3) Chwalislaw. Here, the occurrence of the albitization is well developed and specific in its mineralogical paragenesis. Throughout the sample sites different albitization stages can be observed. The most albitized and therefore reddish facies can be found at the Laski village granite that consists of primary quartz and K-feldspar, biotite, and development of secondary albite, chlorite and hematite forming tiny granules. The albitization of the Laski quarry granite (and granodiorite) developed along fractures. The fractures show alteration gradients with reddish albitized facies at the walls and less albitized and rather pinkish facies away from the fracture zones. The mineral assemblage is similar to the previous section, nevertheless hematite is pigmentary here and calcite occurs. The most southern site of Chwalislaw shows only weak albitization forming pinkish spotted facies with minor hematite and maghemite concentrations. Recent paleomagnetic datations of these Polish albitized sections show a Triassic remagnetization carried by hematite and maghemite (Franke et al., 2009, 2010), related to the Triassic paleosurface. Moreover, based on the albitization degree, the massively hematised/albitized Laski village section seems to be closer to the ancient surface, whereas the fracture controlled albitization of the Laski quarry relates to deeper parts of the paleoprofile and the pinkish spotted facies of the Chwalislaw section are tied to the base of the paleosurface alteration. The albitized outcrops spread along a topographic surface that rises up southward. In detail, the arrangement of the various facies (massive, fracture controlled and spotted) allows to recognize zones where post-Triassic erosion has been more or less important and/or discontinuities due to fault movements. Mapping the albitized facies will allow to reconstruct the Triassic paleosurface and to date some strain events relatively to this surface. Recognizing the Triassic paleosurface is important with respect to the post-paleozoic geodynamic evolution of this crystalline basement. As the paleosurface is widely preserved in the Sudetes, the post-Triassic basement erosion has been weaker than the depth of the albitization profile (~200 m depth). References: Boles J.R., Coombs D.S., 1977. Zeolite facies alteration of sandstones in the southland syncline, New Zealand. American Journal of Science., 277, 982-1012. Cathelineau M., 1986. The hydrothermal alkali metasomatism effects on granitic rocks: Quartz dissolution and related sub-solidus changes.Journal of. Petrology, 27: 945-965. Franke C., Thiry M., Jelenska M., Kodzialko-Hofmokl M., Lagroix F., Parcerisa D., Szuszkiewicz A., Turniak K., 2009. Remagnetization of Variscan massifs and reconstruction of the Triassic paleosurface in Europe, AGU Fall Meeting 2009, San Francisco, USA. Franke, C., Thiry, M., Gomez-Gras, D., Jelenska, M., Kodzialko-Hofmokl, M., Lagroix, F., Parcerisa, D., Spassov, S., and Yao, K., 2010, Paleomagnetic age constrains and magneto-mineralogic implications for the Triassic paleosurface in Europe, EGU General Assembly 2010, Vienna, Austria. Parcerisa D., Thiry M., Schmitt J.M., 2009. Albitisation related to the Triassic unconformity in igneous rocks of the Morvan massif, France. International journal of Earth Science., doi: 10.1007/s00531-008-0405-1. Petersson J,. Eliasson T., 1997. Mineral evolution and element mobility during episyenitisation (dequartzification) and albitization in the postkinematic bohus granite, southwest Sweden, Lithos., 42, 123-146, doi: 10.1016/s0024-4937(97)00040-6. Ricordel C., Parcerisa D., Thiry M., Moreau M.G., Gómez-Gras D., 2007. Triassic magnetic overprints related to albitization in granites from the Morvan massif (France). Palaeo 251 (2007) 268-282.

  12. A MASSIF Effort To Determine The Mass-Luminosity Relation for Stars of Various Ages, Metallicities, and Evolution States

    NASA Technical Reports Server (NTRS)

    Henry, Todd J.; Beedict, G. Fritz; Gies, Douglas R.; Golimowski, David A.; Ianna, Philip A.; Mason, Brian; McArthur, Barbara; Nelan, Edmund; Torres, Guillermo

    2004-01-01

    The MASSIF (Masses and Stellar Systems with Interferometry) Team will use SIM to investigate the mass content of the Galaxy - from huge stars to barely glimmering brown dwarfs, and from hot white dwarfs to exotic black holes. We will target various samples of the Galactic population to determine and relate the fundamental characteristics of mass, luminosity, age, composition, and multiplicity - attributes that together yield an extensive understanding of the stars. Our samples will include distant clusters that span a factor of 5000 in age, and commonplace stars and substellar objects that lurk near the Sun. The principal goals of the MASSIF Key Project are to (1) define the mass-luminosity relation for main sequence stars in five fundamental clusters so that effects of age and metallicity can be mapped (Trapezium, TW Hydrae, Pleiades, Hyades, and M67), and (2) determine accurate masses for representative examples of nearly every type of star, stellar descendant or brown dwarf in the Galaxy.

  13. The Tolbachik volcanic massif: A review of the petrology, volcanology and eruption history prior to the 2012-2013 eruption

    NASA Astrophysics Data System (ADS)

    Churikova, T. G.; Gordeychik, B. N.; Edwards, B. R.; Ponomareva, V. V.; Zelenin, E. A.

    2015-12-01

    The primary goal of this paper is to summarize all of the published data on the Tolbachik volcanic massif in order to provide a clear framework for the geochronologic, petrologic, geochemical and to a lesser extent the geophysical and tectonic characteristics of the Tolbachik system established prior to the 2012-2013 eruption. The Tolbachik massif forms the southwestern part of the voluminous Klyuchevskoy volcanic group in Kamchatka. The massif includes two large stratovolcanoes, Ostry ("Sharp") Tolbachik and Plosky ("Flat") Tolbachik, and a 70 km long zone of the basaltic monogenetic cones that form an arcuate rift-like structure running across the Plosky Tolbachik summit. The Tolbachik massif gained international attention after the 1975-1976 Great Tolbachik Fissure Eruption (GTFE), which was one of the largest eruptions of the 20th century and one of the six largest basaltic fissure eruptions in historical time. By the end of the GTFE, 2.2 km3 of volcanic products of variable basaltic compositions with MORB-like isotopic characteristics covered an area of > 1000 km2. During the following three decades more than 700 papers on various aspects of this eruption have been published both in national and international journals. Although the recent 2012-2013 eruption, which is the main topic of this volume, was not as long as the GTFE in duration or as large in area and volume of the erupted deposits, it brought to the surface a unique volcanic material never found before. In order to understand the data from new eruptions and make significant progress towards a better understanding of the Tolbachik magmatic system it is important to be able to put the new results into the historic context of previous research.

  14. Tectonic and metallogenic model for northeast Asia

    USGS Publications Warehouse

    Parfenov, Leonid M.; Nokleberg, Warren J.; Berzin, Nikolai A.; Badarch, Gombosuren; Dril, Sergy I.; Gerel, Ochir; Goryachev, Nikolai A.; Khanchuk, Alexander I.; Kuz'min, Mikhail I., Obolenskiy, Alexander A.; Prokopiev, Andrei V.; Ratkin, Vladimir V.; Rodionov, Sergey M.; Scotese, Christopher R.; Shpikerman, Vladimir I.; Timofeev, Vladimir F.; Tomurtogoo, Onongin; Yan, Hongquan

    2011-01-01

    This document describes the digital files in this report that contains a tectonic and metallogenic model for Northeast Asia. The report also contains background materials. This tectonic and metallogenic model and other materials on this report are derived from (1) an extensive USGS Professional Paper, 1765, on the metallogenesis and tectonics of Northeast Asia that is available on the Internet at http://pubs.usgs.gov/pp/1765/; and (2) the Russian Far East parts of an extensive USGS Professional Paper, 1697, on the metallogenesis and tectonics of the Russian Far East, Alaska, and the Canadian Cordillera that is available on the Internet at http://pubs.usgs.gov/pp/pp1697/. The major purpose of the tectonic and metallogenic model is to provide, in movie format, a colorful summary of the complex geology, tectonics, and metallogenesis of the region. To accomplish this goal four steps were taken: (1) 13 time-stage diagrams, from the late Neoproterozoic (850 Ma) through the present (0 Ma), were adapted, generalized, and transformed into color static time-stage diagrams; (2) the 13 time-stage diagrams were placed in a computer morphing program to produce the model; (3) the model was examined and each diagram was successively adapted to preceding and subsequent diagrams to match the size and surface expression of major geologic units; and (4) the final version of the model was produced in successive iterations of steps 2 and 3. The tectonic and metallogenic model and associated materials in this report are derived from a project on the major mineral deposits, metallogenesis, and tectonics of the Northeast Asia and from a preceding project on the metallogenesis and tectonics of the Russian Far East, Alaska, and the Canadian Cordillera. Both projects provide critical information on bedrock geology and geophysics, tectonics, major metalliferous mineral resources, metallogenic patterns, and crustal origin and evolution of mineralizing systems for this region. The major scientific goals and benefits of the projects are to: (1) provide a comprehensive international data base on the mineral resources of the region that is the first extensive knowledge available in English; (2) provide major new interpretations of the origin and crustal evolution of mineralizing systems and their host rocks, thereby enabling enhanced, broad-scale tectonic reconstructions and interpretations; and (3) promote trade and scientific and technical exchanges between North America and eastern Asia.

  15. Pyroxenite Formation in the Totalp Ultramafic Massif, Switzerland: Constraints From Highly Siderophile Elements

    NASA Astrophysics Data System (ADS)

    van Acken, D.; Becker, H.; Walker, R. J.; Wombacher, F.

    2009-12-01

    Pyroxenite layers form up to 5% of orogenic ultramafic massifs and may contribute significantly to formation of basaltic melt in the mantle. The processes which lead to the formation of pyroxenite layers are still subject to discussion. While a number of studies consider them high-pressures cumulate precipitates from mantle melts, other studies suggest an origin as residues from subducted slabs of recycled oceanic lithosphere. Understanding the genesis of pyroxenite layers in the mantle may be key to a better understanding of element fluxes and redistribution of elements during melt-rock interaction in the mantle. We present highly siderophile element (HSE) and Os isotope data from spinel and spinel-garnet websterites and clinopyroxenites interlayered with fertile serpentinized peridotites in the Totalp ultramafic massif in eastern Switzerland. The Totalp massif has its origin in the suboceanic MORB source mantle, followed by an episode of refertilization by melt-rock interaction. The pyroxenitic layers possibly represent zones of high melt flow during the refertilization event. Rapid uplift prior to emplacement on the Jurassic Piedmont-Liguria ocean floor in an ultraslow-spreading environment, similar to the present day Gakkel Ridge, prevented equilibration in the shallower mantle and allows study of a section of deep oceanic lithospheric mantle. Highly siderophile elements and Os isotopes have been useful tools for the study of mantle processes such as melt-rock interaction, because of their range in compatibility and their siderophile and chalcophile geochemical behavior. Totalp pyroxenites are depleted in the compatible HSE Os, Ir, and Ru compared to typical mantle lherzolites, along with enrichment in the more incompatible HSE Pt, Pd, and Re. The resulting HSE patterns from clinopyroxenites and some websterites are broadly similar to those seen in basalts, with high Re/Os, Pt/Ir and Pd/Ir. Several websterites from composite websterite-lherzolite samples are less depleted in Os, Ir and Ru, and show enrichment of Pt and Pd over Re. Bulk 187Os/188Os in websterites ranges from 0.1240 to 0.1607. Clinopyroxenites show more radiogenic values between 0.152 and 2.2. The observed HSE signatures are consistent with a cumulate origin of Totalp pyroxenites in zones of increased melt flow during melt-rock interaction near the lithosphere-asthenosphere boundary. Totalp pyroxenites can be considered mixtures between cumulates from infiltrating melts of broadly basaltic composition and up to 30% of depleted peridotite wall rock. Websterites represent the fringes of these high melt flow zones adjacent to peridotite wall rock, while clinopyroxenites almost exclusively preserve the HSE signature of the melt, with little influence from the peridotite host rock. Radiogenic 187Os/188Os of the pyroxenites suggests derivation of the parental melts from a source with a long-term enrichment in Re/Os, such as recycled oceanic crust.

  16. Fluid-Assisted Ductile Strain Localization in the Shallow Subcontinental Lithospheric Mantle (Ronda Massif, Betic Cordillera, S-Spain)

    NASA Astrophysics Data System (ADS)

    Hidas, K.; Tommasi, A.; Garrido, C. J.; Padron-Navarta, J. A.; Mainprice, D.; Barou, F.; Marchesi, C.

    2014-12-01

    The Ronda massif (S-Spain) is the largest (ca. 300km2) of several orogenic peridotite massifs exposed in the Betic and Rif (northern Morocco) mountain belts in the westernmost part of the Alpine orogen that was tectonically emplaced during early Miocene times. Here we report a microstructural study of strain localization in a mylonitic peridotite shear zone that have been formed during the latest ductile history of the massif. Strain localization is associated with a sudden decrease of grain size and the redistribution of orthopyroxene in the finest grained microstructural domains (ultramylonites). Olivine crystallographic preferred orientation (CPO) shows [100]-axes subparallel to the lineation and [001] at the pole of the foliation, whereas orthopyroxene mimics the CPO of that of olivine. Although low-angle misorientations in neighboring pixels are frequent in both phases, olivine and orthopyroxene CPO cannot be explained by coeval deformation via dislocation creep mechanisms. Based on microstructural and major element geochemical data, we propose strain localization at low temperature assisted by interstitial fluids that has led to the dissolution of orthopyroxene porphyroclasts and reprecipitation along the ultramylonite bands.

  17. Lower Pliensbachian caldera volcanism in high-obliquity rift systems in the western North Patagonian Massif, Argentina

    NASA Astrophysics Data System (ADS)

    Benedini, Leonardo; Gregori, Daniel; Strazzere, Leonardo; Falco, Juan I.; Dristas, Jorge A.

    2014-12-01

    In the Cerro Carro Quebrado and Cerro Catri Cura area, located at the border between the Neuqun Basin and the North Patagonian Massif, the Garamilla Formation is composed of four volcanic stages: 1) andesitic lava-flows related to the beginning of the volcanic system; 2) basal massive lithic breccias that represent the caldera collapse; 3) voluminous, coarse-crystal rich massive lava-like ignimbrites related to multiple, steady eruptions that represent the principal infill of the system; and, finally 4) domes, dykes, lava flows, and lava domes of rhyolitic composition indicative of a post-collapse stage. The analysis of the regional and local structures, as well as, the architectures of the volcanic facies, indicates the existence of a highly oblique rift, with its principal extensional strain in an NNE-SSW direction (N10). The analyzed rocks are mainly high-potassium dacites and rhyolites with trace and RE elements contents of an intraplate signature. The age of these rocks (189 0.76 Ma) agree well with other volcanic sequences of the western North Patagonian Massif, as well as, the Neuqun Basin, indicating that Pliensbachian magmatism was widespread in both regions. The age is also coincident with phase 1 of volcanism of the eastern North Patagonia Massif (188-178 Ma) represented by ignimbrites, domes, and pyroclastic rocks of the Marifil Complex, related to intraplate magmatism.

  18. Shear-wave anisotropy beneath Northeast China observed by the NECESSArray

    NASA Astrophysics Data System (ADS)

    Niu, F.; Zhang, X.; Grand, S.; Ni, J. F.; Chen, Y. J.; Ning, J.; Kawakatsu, H.; Tanaka, S.; Obayashi, M.

    2012-12-01

    NNortheast China consists of the Northeast China Plain with the Songliao basin in its center, the Central Asian Fold belt, known as the Great Xing'an Range to the west, the uplifted volcanic Changbaishan region to the east and the Sino-Korean Craton to the south. It is located more than 1000 km away from the Japan Trench, where the Pacific plate starts to subduct beneath the Eurasia plate. It is widely believed that the Songliao Basin was a rifting basin and the rifting process took place in the Jurassic immediately after the closure of the Mongol-Okhotsk Ocean. The collision between the Amurian plate and Siberia blocks after the closure probably caused lithospheric thickening of the Great Xing'an Range and NE China, and the later convective removal of the thickened lithosphere could have resulted in a thinned lithosphere. Late Mesozoic volcanic rocks are widely distributed in the region, indicating that active volcanism occurred during the Mesozoic rifting. Volcanism continued in the Cenozoic time in a rather episodic and sporadic manner. Although it is generally believed that the Cenozoic volcanism in NE China is somehow related to the subduction of the Pacific plate beneath the area, one obviously cannot invoke a regular back arc volcanogenic model to explain the Cenozoic volcanism in this region. One promising model, based on tomographic imaging, is the so-called big-mantle-wedge (BMW) model, which hypothesizes a large-scale mantle upwelling in this region as the deep origin of the Cenozoic volcanism. We measured seismic anisotropy in the upper mantle using core shear phases recorded by a large-scale international deployment (the NorthEast China Extended SeiSmic Array, NECESSArray) to investigate mantle flow beneath NE China. We employed a multi-event signal-to-noise ratio (SNR) weighted method and obtained measurements of splitting parameters at 126 stations. Overall, the observed SKS splitting times are of low amplitude (~0.8 s), indicating that the underlying mantle experienced relatively weak deformation in this region. Overall the study region shows a NW-SE fast direction, which is close to the absolute plate motion (N64W, NUVEL-1A model, Gripp and Gordon, 2002), but is difficult to conciliate with the EW flow expected by the BMW model. The observed anisotropy also varies consistently from place to place and exhibits an asymmetric pattern across the Songliao basin. At the southeast and east edge of the Songliao basin, the fast axis aligns along the NW-SE direction, whereas the axis rotates slightly to NNW toward northeast beneath the Jiamusi massif and the Sanjiang basin. At the west edge of the basin where the North South Gravity Lineament (NSGL) is located, we found significant scatter in the fast-axis direction.

  19. Northeast Egypt as seen from STS-58

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This oblique view, looking northeast from central Egypt, shows great expanses of the sand covered and rocky Western Desert in the foreground (bottom). The dark patches bottom right are the Dakhla Oases on the south side of an escarpment. The northern half of Egypt's Nile appears here, from about the latitude of Luxor to the delta. Green colors indicate the small area of crops which feed Egypt's population of 55 million. The Nile Delta is partly obscured by a band of clouds, but can be discerned at the coast as a flattened triangle of green. The smaller triangle close by is the Falyum Basin, a depression irrigated by water from the Nile. The coast of the Mediterranean Sea appears left.

  20. Fast retreat of Zachari Isstrm, northeast Greenland

    NASA Astrophysics Data System (ADS)

    Mouginot, J.; Rignot, E.; Scheuchl, B.; Fenty, I.; Khazendar, A.; Morlighem, M.; Buzzi, A.; Paden, J.

    2015-12-01

    After 8 years of decay of its ice shelf, Zachari Isstrm, a major glacier of northeast Greenland that holds a 0.5-meter sea-level rise equivalent, entered a phase of accelerated retreat in fall 2012. The acceleration rate of its ice velocity tripled, melting of its residual ice shelf and thinning of its grounded portion doubled, and calving is now occurring at its grounding line. Warmer air and ocean temperatures have caused the glacier to detach from a stabilizing sill and retreat rapidly along a downward-sloping, marine-based bed. Its equal-ice-volume neighbor, Nioghalvfjerdsfjorden, is also melting rapidly but retreating slowly along an upward-sloping bed. The destabilization of this marine-based sector will increase sea-level rise from the Greenland Ice Sheet for decades to come.

  1. Fast retreat of Zachari Isstrm, northeast Greenland.

    PubMed

    Mouginot, J; Rignot, E; Scheuchl, B; Fenty, I; Khazendar, A; Morlighem, M; Buzzi, A; Paden, J

    2015-12-11

    After 8 years of decay of its ice shelf, Zachari Isstrm, a major glacier of northeast Greenland that holds a 0.5-meter sea-level rise equivalent, entered a phase of accelerated retreat in fall 2012. The acceleration rate of its ice velocity tripled, melting of its residual ice shelf and thinning of its grounded portion doubled, and calving is now occurring at its grounding line. Warmer air and ocean temperatures have caused the glacier to detach from a stabilizing sill and retreat rapidly along a downward-sloping, marine-based bed. Its equal-ice-volume neighbor, Nioghalvfjerdsfjorden, is also melting rapidly but retreating slowly along an upward-sloping bed. The destabilization of this marine-based sector will increase sea-level rise from the Greenland Ice Sheet for decades to come. PMID:26563135

  2. Timing and tectonic history of UHP rocks from the Rhodope Massif, Bulgaria

    NASA Astrophysics Data System (ADS)

    Collings, David; Savov, Ivan; Eccles, Kathryn; Baxter, Ethan; Harvey, Jason

    2013-04-01

    Microdiamond inclusions in garnet delineate the Rhodope Massif (RM) as a globally important UHP locality. To date there are 4 confirmed UHP localities across the RM, with UHP indicators being restricted to garnets from metapelites. All available protolith and metamorphic ages from the RM are based on accessory minerals such as zircon and monazite, which yield a disparate array of ages spanning from pre-Variscan to post-Alpine (Eocene) times. The best estimate for the timing of the UHP event is that it was associated with a subduction event during the Jurassic1. This study focuses on garnets from UHP metapelites from the Central Rhodope Mts., Bulgaria, in the vicinity of the town of Chepelare. It is the first to date directly the host of the UHP indicators in the region, eliminating the risks of interpretations based on inherited inclusions. Aggregates of garnets have been dated via Sm/Nd geochronology, following a rigorous sample preparation and partial dissolution process to remove the effect of REE rich inclusions that result in low Sm/Nd ratios. Aggregate garnet ages range between 91.5 4.6 Ma and 70.3 2.3 Ma, which correlates well with the age of magmatic activity seen across the region. These Late Cretaceous ages are significantly younger than the proposed Jurassic UHP metamorphic event, but correlate well with another proposed (U)HP event, based on U-Pb zircon dating2. Current tectonic models for the RM invoke either a protracted subduction cycle with a single, long lasting (>30Ma long) exhumation event, or a series of complex subduction -exhumation cycles preserved in multiple suture zones. We will attempt to link our new garnet Sm/Nd ages with the complex post-Jurassic tectonic evolution of the RM, and in particular add constraints to the much debated questions surrounding the nature of the exhumation of the UHP units and the evolution of the massif. 1Burg, J., 2011, Journal of the Virtual Explorer, 42, paper 1 2Liati, A.,et al., 2011,. In Dobrzhinetskaya, L. and Cuthbert, S.(Editors), Ultrahigh Pressure Metamorphism. Elsevier, London, pp. 295-324.

  3. CELEBRATION 2000: P-wave velocity models of the Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Hrubcova, P.

    2003-04-01

    Deep structure of the Bohemian Massif (BM), the largest stable outcrop of Variscan rocks in Central Europe, was studied along two refraction profiles, CEL09 that traverses the whole massif in the NW-SE direction, and CEL10 that extends along its eastern edge almost perpendicularly to CEL09. Good quality recordings with clear first arrivals of crustal and upper mantle phases show apparent velocity 5.9 km/s for the upper crust with slightly higher gradient in NW part of the BM and app. velocity 8.0 to 8.1 km/s for the upper mantle. Decrease of amplitudes of crustal phases visible in some sections may be connected with a specific upper crustal structure (zero to negative velocity gradient zone). Pronounced Moho reflections in central part of the BM suggest well-defined Moho in that part and not so clear Moho with smaller velocity contrast in other parts of the BM. For interpretation, the tomographic inversion routine of Hole (1992) was used as an efficient tool to determine seismic P-wave velocity distribution in the crust using first arrivals. Tomographic models were verified by forward ray tracing modelling based on well-established algorithm developed by Cerveny et al. (1983), where apart from first arrivals also further phases were included. 2-D velocity models of first arrivals and reflected phases show high P-wave velocity gradient zone reaching the depth of 5-7 km followed by small gradient and laterally homogeneous P-wave velocity distribution in the middle crust. Differences in velocity distribution in the lower crust delimit central part of the BM (sharp Moho discontinuity) from other tectonic units within the BM (lower crust high gradient transition zone). Position of Moho discontinuity ranging from 32 km to 40 km and reflectors within the crust complement the P-wave velocity distribution. Presented models also show the contact of the BM with its neighbouring units - Carpathians, Paleozoic Platform, Vienna Basin and the Alps. References: Cerveny, V., Psencik, I., 1983. Program SEIS83, Numerical Modelling of Seismic Wave Fields in 2-D Laterally Varying Layered Structures by the Ray Method, Charles University, Prague. Hole, J.A. 1992: Non-linear high-resolution three-dimensional seismic travel time tomography, J. Geophys. Res. 97, 6553-6562.

  4. Methane Seepage at Hyperalkaline Springs in the Ronda Peridotite Massif (Spain)

    NASA Astrophysics Data System (ADS)

    Etiope, G.; Vadillo, I.; Whiticar, M. J.; Marques, J. M.; Carreira, P. M.; Tiago, I.; Benavente, J.; Jimenez, P.; Urresti, B.

    2014-12-01

    Methane-rich, hyperalkaline spring waters and bubbling pools have been sampled in the Ronda peridotite massif in southern Spain. Water chemistry (T: 17.1-21.5 C; pH: 10.7-11.7; DO: <2 mg/L; Ca-OH facies) is characteristic of present-day serpentinization. Dissolved CH4 concentrations range from 0.1 to 3.2 mg/L. CH4 stable C and H isotope ratios suggest a dominant abiotic origin in two natural spring sites (delta13C: -13 to -29 VPDB; delta2H: -309 to -333 VSMOW) and a mixed biotic-abiotic origin in springs with artificial water delivery systems (i.e., pipes or fountains; delta13C: -44 to -69 ; delta2H: -180 to -319 ). At the natural springs, gas is mainly released through bubbles close to the water outlet (CH4 flux ~1 kg/day by individual bubble trains), and subordinately by microseepage from the ground, even at distances of ~100 m from the bubble-spring site (flux of 10's, up to 97, mg CH4 m-2day-1). Gas seepage is strictly controlled by faults. Under-saturation of CH4 in water, bubbling and seepage location suggest that CH4 is not exclusively transported to the surface by hyperalkaline water, but it follows autonomous migration pathways along faults. Similar 'dry' seepage of abiotic gas was observed in the Philippines, New Zealand, Turkey and Italy. Like other land-based serpentinization systems, the Ronda peridotite massif is characterized by low heat flow (<40 mW/m2), with temperatures <60C at depths of 1.5 km. At these low T and high pH conditions, CO32- is the only available carbon source dissolved in the water, and unlikely contributes to catalysed Fischer-Tropsch Type reactions. Methane production from CO2 hydrogenation in a gas phase system (unsaturated fractured rocks) cannot be excluded. The presence of ruthenium-enriched chromitites in the Ronda peridotites may support the hypothesis that CH4 is produced by CO2 hydrogenation catalyzed by Ru minerals, even at temperatures below 100C, as demonstrated in recent laboratory experiments (Etiope and Ionescu, 2014, Geofluids, in press).

  5. Cl-rich hydrous mafic mineral assemblages in the Highiș massif, Apuseni Mountains, Romania

    NASA Astrophysics Data System (ADS)

    Bonin, Bernard; Tatu, Mihai

    2016-01-01

    The Guadalupian (Mid-Permian) Highiș massif (Apuseni Mountains, Romania) displays a bimodal igneous suite of mafic (gabbro, diorite) and A-type felsic (alkali feldspar granite, albite granite, and hybrid granodiorite) rocks. Amphibole is widespread throughout the suite, and yields markedly high chlorine contents. Three groups are identified: Cl-rich potassic hastingsite (2.60-3.40 wt% Cl) within A-type felsic rocks and diorite, mildly Cl-rich pargasite to hornblende (0.80-1.90 wt% Cl) within gabbro, and low F-Cl hornblende within gabbro and hybrid granodiorite. Coexisting biotite is either Cl-rich within diorite, or F-Cl-poor to F-rich within A-type felsic rocks. Chlorine and fluorine are distributed in both mafic phases, according to the F-Fe and Cl-Mg avoidance rules. The low-Ti contents suggest subsolidus compositions. Cl-rich amphibole within diorite and A-type felsic rocks yields a restricted temperature range - from 575 °C down to 400 °C, whereas mildly Cl-rich amphibole within gabbro displays the highest range - from 675 to 360 °C. Temperatures recorded by Cl-rich biotite within diorite range from 590 to 410 °C. Biotite within A-type felsic rocks yields higher temperatures than amphibole: the highest values- from 640 to 540 °C - are recorded in low-F-Cl varieties, whereas the lowest values- from 535 to 500 °C - are displayed by F-rich varieties. All data point to halogen-rich hydrothermal fluids at upper greenschist facies conditions percolating through fractures and shear zones and pervasively permeating the whole Highiș massif, with F precipitating as interstitial fluorite and Cl incorporating into amphibole, during one, or possibly several, hydrothermal episodes that would have occurred during a ~ 150 My-long period of time extending from the Guadalupian (Mid-Permian) to the Albian (Mid-Cretaceous).

  6. Link between surface temperature and documented rockfalls in the Mont Blanc massif rockwalls

    NASA Astrophysics Data System (ADS)

    Magnin, Florence; Deline, Philip; Ravanel, Ludovic

    2014-05-01

    Recent studies show that rockfall activity has increased along the three past decades in high mountain areas, and permafrost degradation is regarded as the main triggering factor. 433 rockfalls affecting the steep rockwalls of the Mont Blanc massif have been inventoried and documented (time and precise location, topographical and geological settings, volume, conditions, etc.) from 2007 to 2011. With the aim of better understanding geomorphic processes, we address questions about the thermal state of the unstable rockwalls within this study area. A statistical model of the Mean Annual Rock Surface Temperature (MARST) for the 1961-1990 period has been implemented on a 4-m-resolution DEM of the Mont Blanc massif. The model runs with Potential Incoming Solar radiation (PISR) calculated with GIS tools and air temperature parameters computed from Chamonix Mto France's records. 87 rockfalls are located at the geographical margins of the DEM, where the PISR calculation doesn't take account of the surrounding hillshading and biased MARST simulation. Thus, only 346 rockfalls were kept and linked to a MARST value after data sorting. Preliminary results show that rockfalls occurred over a modelled MARST range of -6C to 5C. MARSTs ranging from -2.5C to 2.5C encompass about 60% of the rockfalls. The mean MARST value for the 346 rockfalls is of -0.9C. Simulated warm permafrost areas (> -2C) are therefore appearing as the most affected by instabilities. These first observations reinforce the hypothesis that permafrost degradation is likely the dominant triggering factor of these rockfalls. The 1961-1990 period is supposed to be representative of the conditions at depth that are not affected by the recent climate warming. This means that the here presented results are mainly valuable for rockfalls related to pluri-decadal signal. But they also suggest that MARST model is an interesting tool to explore the link between rockwall instability and permafrost state. Simulations at various time scales would allow more precise reconstruction of the bedrock temperature during each year of rockfalls. Model possibilities and the related outcomings will be also presented.

  7. CRE dating on the scarps of large landslides affecting the Belledonne massif ( French Alps)

    NASA Astrophysics Data System (ADS)

    Lebrouc, V.; Baillet, L.; Schwartz, S.; Jongmans, D.; Gamond, J. F.; Bourles, D.; Le Roux, O.; Carcaillet, J.; Braucher, R.

    2012-04-01

    The southwestern edge of the Belledonne Massif (French Alps) consists of micaschists unconformably covered with Mesozoic sediments and Quaternary deposits. The morphology corresponds to a glacial plateau (Mont Sec plateau) bordered by steep slopes (around 40°), where moraines and peat bog subsist. The massif is incised by the East-West trending Romanche valley that was shaped by several cycles of quaternary glaciations and deglaciations. Slopes are affected by several active or past large scale rock mass instabilities. Cosmic Ray Exposure (CRE) dating was applied on the head scarps of three large landslides, one of which being the active Séchilienne landslide whose headscarp was already dated by Leroux et al. [2009]. Dating results suggest a concomitant initiation of these instabilities at about 7 ± 2 10Be ka, thousands years after the total downwastage of the valley. A different kinematic behaviour was however observed on two contiguous landslides for which continuous exposure profiles were obtained. On the Séchilienne landslide, 23 samples were collected from internal and lateral scarps, as well as on polished bedrock surfaces, with the aim of dating the internal kinematics of the landslide. Preliminary dating results obtained on polished surfaces and near the top of the scarps show unexpected low 10Be concentrations, suggesting the existence of thin moraine or peat bog deposits masking the bedrock, which have been subsequently eroded. The minimum thickness of these deposits was estimated assuming a constant denudation rate over time. Exposure date profiles show that the studied lateral and internal scarps were initiated at the same period as the Sechilienne headscarp. An increase in the exposure rate was also observed between 2 and 1 ka, in agreement with that evidenced along the headscarp. Forty other samples have been collected in the landslide to corroborate these results. Reference Le Roux, O., S. Schwartz , J.-F. Gamond, D. Jongmans, D. Bourles, R. Braucher, W. Mahaney, J. Carcaillet, and L. Leanni (2009). CRE dating on the head scarp of a major landslide (Séchilienne, French Alps), age constraints on Holocene kinematics. Earth and Planetary Science Letters, Vol. 280, 236-245.

  8. Seismotectonic significance of the 2008-2010 Walloon Brabant seismic swarm in the Brabant Massif, Belgium

    NASA Astrophysics Data System (ADS)

    Van Noten, Koen; Lecocq, Thomas; Shah, Anjana K.; Camelbeeck, Thierry

    2015-08-01

    Between 12 July 2008 and 18 January 2010 a seismic swarm occurred close to the town of Court-Saint-Etienne, 20 km SE of Brussels (Belgium). The Belgian network and a temporary seismic network covering the epicentral area established a seismic catalogue in which magnitude varies between ML -0.7 and ML 3.2. Based on waveform cross-correlation of co-located earthquakes, the spatial distribution of the hypocentre locations was improved considerably and shows a dense cluster displaying a 200 m-wide, 1.5-km long, NW-SE oriented fault structure at a depth range between 5 and 7 km, located in the Cambrian basement rocks of the Lower Palaeozoic Anglo-Brabant Massif. Waveform comparison of the largest events of the 2008-2010 swarm with an ML 4.0 event that occurred during swarm activity between 1953 and 1957 in the same region shows similar P- and S-wave arrivals at the Belgian Uccle seismic station. The geometry depicted by the hypocentral distribution is consistent with a nearly vertical, left-lateral strike-slip fault taking place in a current local WNW-ESE oriented local maximum horizontal stress field. To determine a relevant tectonic structure, a systematic matched filtering approach of aeromagnetic data, which can approximately locate isolated anomalies associated with hypocentral depths, has been applied. Matched filtering shows that the 2008-2010 seismic swarm occurred along a limited-sized fault which is situated in slaty, low-magnetic rocks of the Mousty Formation. The fault is bordered at both ends with obliquely oriented magnetic gradients. Whereas the NW end of the fault is structurally controlled, its SE end is controlled by a magnetic gradient representing an early-orogenic detachment fault separating the low-magnetic slaty Mousty Formation from the high-magnetic Tubize Formation. The seismic swarm is therefore interpreted as a sinistral reactivation of an inherited NW-SE oriented isolated fault in a weakened crust within the Cambrian core of the Brabant Massif.

  9. Collapse in a rock massif induced by lateral confinement loss: the case of Montegolf (Mlaga, Spain)

    NASA Astrophysics Data System (ADS)

    Azan, J. M.; Puertas, E.; Urea, C.; Gallego, R.; Romero-Gmez, F.

    2012-04-01

    The use of computing codes allowing finite elements analysis is a very useful tool in detecting variations of the tensional state of rock massifs. Most of the codes used for ground modelling only allow 2D analysis. However, in the case of complex slope instabilities, it is necessary to consider the variation of resistant properties in a 3D model. This work presents an example in which 3D analysis carried out by finite elements methods becomes essential to understand the surface processes occurred in a urbanized rock massif (Montegolf, Malaga). The studied area is a small hill of elliptical shaped plan (300x200m plan). As a main peculiarity of this hill, it was intensively undergone to human activity in recent years. On September 11th, 2000, the collapse of an inner cavity (100m3 in volume) took place. The cavity proceeded from a mining abandoned 30 years before. The application of a 3D finite elements model showed that the highway slope digged in the Eastern face of the mount produced a change in the tensional state inside the mount. Vertical stresses shifted from compression to tension eliminating the vault effect. To define the geometry of the model, a survey of the existing contour map was carried out and conveniently transformed into ACIS format to be processed by ABAQUS (finite elements program). In the two-dimensional case an E-W section involving houses, highway and cavity was chosen. Mining hole was considered in the model, using a 10m-diameter sphere to represent the cavity. The performance of the natural materials was supposed to be elastic so Young modulus and Poisson's ratio were required. The ground strains due to collapse of the cavity and obtained by the finite elements model were accurately related to the mapping of cracks on the surface, the sinking of topographical landmarks (located on the top of the mountain) and the photographic analysis (captures before and after the collapse). Thus it is confirmed that the surface sliding which affected the residential house Montegolf was caused by the collapse of a cavity inside the mount. 3D models confirmed that the highway slope digged on the mount and the subsequent instabilities in that slope were the main conditioning factors of this collapse.

  10. Crustal Structure in the Vicinity of IODP Hole U1309D, Atlantis Massif

    NASA Astrophysics Data System (ADS)

    Harding, A. J.; Arnulf, A. F.

    2012-12-01

    The Atlantis Massif oceanic core complex (OCC) was formed initially by faulting within the axial zone of the Mid-Atlantic Ridge at 30N, followed by strain localization and unroofing along a detachment surface between 0.5-1.5 Ma. IODP Hole U1309D extends approximately 1.4 km into the Central dome of the Massif and sampled primarily gabbroic rocks. As a relatively deep hole, U1309D is an attractive target for addressing one of the long-term goals of ocean drilling: better integration of borehole geophysical and geologic sampling with surface seismic results. In addition, a number of high quality multichannel seismic (MCS) profiles pass close to the hole. In winter 2012, IODP Expedition 340T reentered U1309D and collected a vertical seismic profile (VSP) as well as high-quality sonic, resistivity, and temperature logs over the entire extent of the Hole. We will present a synthesis, comparing the seismic results from the reprocessing and waveform inversion of all MCS lines passing near Hole U1309D with the results from the new VSP and sonic logs. The waveform inversion results build upon earlier tomographic inversion of downward continued data (Henig et al, 2012) but exhibit significantly improved vertical and horizontal resolution, allowing better integration with the borehole data. Waveform inversion of the nearest flowline MCS profiles that crosses the Central dome just to the north indicates that the original upper surface of the gabbroic body drilled at Hole 1309D now lies just to the west of the hole. Imaging reveals a sharp, almost planar contact, that dips steeply at about 30. Based upon seismic velocities and seafloor sampling and observations, the rocks on other side of the contact are most likely serpentinized peridotite but other lithologies cannot be ruled out (Henig et al,2012). Reprocessing of the reflection image contains few, if any, coherent reflections from within the core of the gabbroic body but there are reflections adjacent to the western contact and near the eastern edge of the body beneath the volcanic hanging wall in regions where the waveform inversion results show the largest velocity variation. The reflections along the western contact require more analysis but suggest that the fluid flow and alteration patterns within the deeper parts of U1309D could be significantly influenced by proximity to the edge of the gabbroic body.

  11. Groundwater hydrodynamics of ancient fan deltas: The case of Sant Lloren del Munt Massif (NE Spain)

    NASA Astrophysics Data System (ADS)

    Angls, Marc; Folch, Albet; Oms, Oriol; Maestro, Eudald; Mas-Pla, Josep

    2014-05-01

    Hydrogeological models based on well-exposed mountain massifs permitt to constrain the geological factors affecting water circulation and water-rock interaction. Our study adresses the question of how sudden lateral rock changes (sedimentologic facies evolution) affect hydrodinamics in the case of ancient fan deltas. A robust model for the Sant Lloren del Munt massif (Eocene, Barcelona province) has been defined after the integration of geology (stratigraphy, sedimentology, mapping and integration of subsurface data) and groundwater hydrology (pumping tests, major ions hydrochemistry and environmental isotopes). Ten lito-hidrostratigraphic units have been recognized, which correspond to different sedimentary environments and have a distinctive response to water circulation and water-rock interaction. A remarkable point of this case study is that the size of the whole sedimentary system is considered, i.e. the lateral expansion of flow (lateral permeability barriers) is fully contrained. In terms of hydrogeology, hydraulic conductivity due to fracturing provide poor aquifers in 4 rock types. 5 hydrochemical groups have been established which allow explaining the evolution of the flow throughout the fan delta. Together with isotopic and stratigraphic data the main recharge areas have been determined. Flow dynamics throughout the system combines both surface runoff and subsurface flow. In proximal alluvial conglomerates, groundwater runs both vertically (fractures) and horizontally (fractured and karstified levels). Some features that are generally overlooked in hydrogeological studies (such as conglomerate petrology) are crucial for fracturation and karstic development. Laterally, conglomerates evolve to impermeable mudstones with sandstones (alluvial fan fringe). However, some conglomerates prograding locally reach distal (marine) sediments and recharge the fractured delta front sandstones aquifers that are also refilled by runoff waters. The end sediments (prodelta marls) provide an ultimate permeability barrier of the system. In general, lithologies arrangement due to past fluctuating distribution of sediments (sedimentary architecture) are crucial in the vertical and horizontal location of the aquifers levels. Interestingly, our study based on ancient rocks can also be applied to present day systems. Original sediments with important primary porosity are later better cemented (lithified) into indurated rocks and then more fracturated. So that, it indicates that in current and ancient fan deltas, better aquifers levels develop in the same strata independently of the transmisivity origin (primary porosity or fracturation).

  12. Isotope Sm-Nd age of the paleoproterozoic PGE-bearing Monchetundra massif trachytoid gabbronorites (Fennoscandian shield)

    NASA Astrophysics Data System (ADS)

    Kunakkuzin, Evgeniy; Bayanova, Tamara; Serov, Pavel; Borisenko, Elena

    2015-04-01

    Monchetundra massif is located in the central part of the Kola Peninsula (Russia) and it is the south-eastern part of the Main Ridge Intrusion. Monchetundra massif together with well-known layered mafic-ultramafic PGE-bearing intrusions in the Fennoscandian shield such as the Fedorovo-Pansky complex, the mt. Generalskaya, the Monchepluton is of interest as a target for the PGE prospecting (Mitrofanov et al. 2006; Nerovich et al., 2009; Grokhovskaya et al., 2003). According to some previously researchers (Nazimova, Rayan, 2008, Nerovich et al., 2009, Layered intrusions…p.1, 2004) rocks of the Monchetundra massif is subdivided into two to five syngenetic zones. Hence the last isotope-geochronological and isotope-geochemical data revealed that the massif includes at least four groups of mafic rocks distinguished by formation ages (Bayanova et al., 2010). The aim of this work is to present Sm-Nd dating results of trachytoid gabbronorites, which are the second mafic rocks group in the Monchetundra massif. The Sm-Nd investigations for these rocks were carried out for the first time. The second group of mafic rocks comprises of medium-grained and coarse-grained mesocratic gabbronorites of trachytoid texture, with they characterized by well-preserved primary magmatic minerals and gabbro-ophitic texture. The U-Pb ages on single zircon-baddeleyite for these rocks recently obtained (2505 ± 6 Ma, 2501 ± 8 Ma, 2504.4±2.7 Ma and 2507.5±7.7 Ma (Layered intrusions…p.1., 2004, Borisenko et al., 2013)). Two samples of trachytoid gabbronorites were selected to study these rocks by Sm-Nd isotopic method. Mineral isochrons plotted from plagioclase, ortho- and clinopyroxene and whole-rock minerals gave ages of 2496±27 (MSWD = 0.9; ɛNd = -1.6±0.5) and 2492±55 Ma (MSWD = 0.5; ɛNd = -1.7±0.5). The new Sm-Nd ages obtained are close to the U-Pb data on zircons and baddeleyites for this rocks group and consider as oridin of second mafic rocks group. All investigations are devoted to memory of academician RAS, professor F. Mitrofanov (Russia), he was a leader of scientific school for geology, geochemistry and metallogeny of ore deposits. The researches are conducted with the financial support of RFBR 13-05-00493, OFI-M 13-05-12055, IGCP-SIDA 599.

  13. Microstructural Observations of an `Oceanic Core Complex': Atlantis Massif, 30oN, mid-Atlantic Ridge

    NASA Astrophysics Data System (ADS)

    Schroeder, T.; John, B. E.; Kelley, D.

    2001-12-01

    The domal high of Atlantis Massif, an inside-corner high at 30oN on the mid-Atlantic Ridge, is presumed to be the footwall of a major slip detachment fault system. Deformation textures in samples of gabbro and peridotite collected from the massif follow a down-temperature path in which high-temperature strain fabrics are overprinted by progressively lower temperature deformation, consistent with unroofing of the massif during progressive normal faulting. Locally preserved granulite facies strain fabrics, most common in the upper 1500m of the massif, include dynamically recrystallized olivine that delineate the early history of normal faulting. Hydrous, amphibolite facies deformation and metasomatic veins of amphibole schist commonly overprint granulite textures in peridotite. Pyroxene was metamorphosed in shear zones to form fine-grained schist composed of strain-free, pale-brown hornblende rimmed and/or overgrown by tremolite. These amphiboles have a strong preferred orientation (SPO and CPO), and are aligned parallel to vein walls. Rimming and overgrowth of hornblende by tremolite indicates deformation continued as temperatures dropped from amphibolite to greenschist conditions. Transitional brittle/plastic and cataclastic fabrics occur at variable depths, but are most common in the upper part of the massif. A 0.5 to 1 meter thick deposit of moderately- to well-indurated carbonate deposited as calcareous ooze and containing fauna of pteropods, foraminifera, and coccoliths unconformably overlies these footwall rocks. This deposit was cemented by precipitation of aragonite in pore space and/or recrystallization of biologic material composed of aragonite to crystalline sparite. Precipitation and recrystallization of aragonite resulted from serpentinization-derived fluids percolating diffusely through the sediment column. Crosscutting, filled fractures suggest that calcareous ooze infiltrated joints and active faults in footwall rocks and prior lithified carbonate, and were involved in continued deformation. Recrystallized, lithified ooze deformed concurrently with tremolite and talc growth in zones of carbonate-tremolite-talc schist, and/or is the matrix of cohesive fault breccias. These relations suggest that core complex faulting was concurrent with deposition and lithification of the carbonate. Serpentinization and faulting therefore continued after footwall rocks were unroofed and exposed at the seafloor.

  14. Palaeomagnetic constraints on the evolution of the Atlantis Massif oceanic core complex (Mid-Atlantic Ridge, 30N)

    NASA Astrophysics Data System (ADS)

    Morris, A.; Pressling, N.; Gee, J. S.

    2011-12-01

    Oceanic core complexes expose lower crustal and upper mantle rocks on the seafloor by tectonic unroofing in the footwalls of large-slip detachment faults. They represent a fundamental component of the seafloor spreading system at slow and ultraslow axes. One of the most extensively studied oceanic core complexes is Atlantis Massif, located at 30N at the intersection of the Atlantis Transform Fault and the Mid Atlantic Ridge (MAR). The central dome of the massif exposes the corrugated detachment fault surface and was drilled during IODP Expedition 304/305 (Hole U1309D). This sampled a 1.4 km faulted and complexly layered footwall section dominated by gabbroic lithologies with minor ultramafic rocks. Palaeomagnetic analyses demonstrate that the gabbroic sequences at Atlantis Massif carry highly stable remanent magnetizations that provide valuable information on the evolution of the section. Thermal demagnetization experiments recover high unblocking temperature components of reversed polarity (R1) throughout the gabbroic sequences. Correlation of structures observed on oriented borehole (FMS) images and those recorded on unoriented core pieces allows reorientation of R1 remanences. The mean remanence direction in true geographic coordinates constrains the tectonic rotation experienced by the Atlantis Massif footwall, indicating a 466 counterclockwise around a MAR-parallel horizontal axis trending 0116. The detachment fault therefore initiated at a steep dip of >50 and then rotated flexurally to its present day low angle geometry (consistent with a 'rolling-hinge' model for detachment evolution). In a number of intervals, the gabbros exhibit a complex remanence structure with the presence of additional intermediate temperature normal (N1) and lower temperature reversed (R2) polarity components, suggesting an extended period of remanence acquisition during different polarity intervals. Sharp break-points between different polarity components suggest that they were acquired by a thermal mechanism. There appears to be no correlation between remanence structure and either the igneous stratigraphy or the distribution of alteration in the core. Instead, the remanence data are consistent with a model in which the lower crustal section acquired magnetizations of different polarity during a protracted cooling history spanning two geomagnetic reversals. The crystallization age of the section (1.2 Ma; derived from Pb/U zircon dating) suggests that the R1 component was acquired during geomagnetic polarity chron C1r.2r, N1 during chron C1r.1n (Jaramillo) and R2 during chron C1r.1r. By considering the maximum time intervals available for acquisition of the N1 and R2 components and correcting laboratory unblocking temperatures accordingly, the data provide additional constraints on the thermal evolution of the Atlantis Massif footwall.

  15. Internal structure of the Aar Massif: What can we learn in terms of exploration for deep geothermal energy?

    NASA Astrophysics Data System (ADS)

    Herwegh, Marco; Baumberger, Roland; Wehrens, Philip; Schubert, Raphael; Berger, Alfons; Maeder, Urs; Spillmann, Thomas

    2014-05-01

    The successful use of deep geothermal energy requires 3D flow paths, which allow an efficient heat exchange between the surrounding host rocks and the circulating fluids. Recent attempts to exploit this energy resource clearly demonstrate that the new technology is facing sever problems. Some major problems are related to the prediction of permeability, the 3D structure of the flow paths and the mechanical responses during elevated fluid pressures at depths of several kilometers. Although seemingly new in a technical perspective, nature is facing and solving similar problems since the beginning of the Alpine orogeny. Based on detailed studies in the Hasli Valley (Aar Massif) we can demonstrate that deformation and fluid flow are strongly localized along mechanical anisotropies (e.g. lithological variations, brittle and ductile faults). Some of them already evolved during Variscan and post-Variscan times. Interestingly, these inherited structures are reactivated over and over again during the Alpine orogeny. Their reactivation occurred at depths of ~13-15 km with elevated temperatures (400-475C) and involved both ductile and brittle deformation processes. Brittle deformation in form of hydrofracking was always present due to the circulating fluids. It is this process, which was and still is responsible for seismic activity. With progressive uplift and exhumation of the Aar Massif, ductile deformation structures became replaced by brittle cataclasites and fault gouges during fault activity at shallower crustal levels. Existing hydrotest data from the Grimsel Test Site (Nagra's underground research laboratory) indicate that these brittle successors of the ductile shear zones are domains of enhanced recent fluid percolation. Note that although being exposed today, the continuation of these fault structures are still active at depth in both brittle and ductile deformation modes, a fact that can be inferred from recent uplift rates and the active seismicity. On the scale of the Aar Massif, the aforementioned deformation sequence induced a complex and dense network of large-scale fault zones. The 3D structure of this network and the associated spacing between the individual faults strongly depends on the type of host rock, intensity of background strain and the location (kinematics) within the massif. Similar effects have to be expected in the crystalline rocks underneath the sedimentary cover in Northern Switzerland. However, based on the aforementioned findings, several facts might be in favor for future exploration of deep geothermal energy in the Aar Massif: (i) enhanced permeability in brittle fault rocks, (ii) dense 3D network auf brittle faults, (iii) weak vegetation allows a reliable projection of the structures to depth as well as tracking of their lateral continuation (crucial for estimates on seismic potential) and last but not least the existence of an elevated geothermal gradient.

  16. Raman mapping of coesite inclusions in garnet from the Kokchetav Massif (Northern Kazakhstan).

    PubMed

    Korsakov, Andrey V; Hutsebaut, Didier; Theunissen, Karel; Vandenabeele, Peter; Stepanov, Alexander S

    2007-12-15

    Coesite inclusions occur in a wide range of lithologies and coesite is therefore a powerful ultrahigh-pressure (UHP) indicator. The transformation of coesite to quartz is evidenced by three optically well identifiable characteristics (e.g. palisade textures, radial crack patterns, polycrystalline quartz pseudomorphs). Under overpressure monomineralic coesite (on an optical basis), lacking the above transformation characteristics may survive. Raman micro-spectroscopy was applied on monomineralic coesite inclusions in garnet porphyroblasts from diamond-bearing garnet-clinozoisite-biotite gneisses of the Barchi-Kol area (Kokchetav Massif, Northern Kazakhstan). These coesite inclusions are euhedral and display a characteristic anisotropic hallo. However, Raman maps and separate spectra of these inclusions display shifted bands for coesite and quartz. Microscopically undetectable, quartz shows on the Raman map as a thin shell around coesite inclusion. Shift of the main coesite band allows to estimate their overpressure: coesite inclusions record 0-2.4 GPa in garnet and zircon. The quartz shell remains under lower pressure 0-1.6 GPa. The possible application of coesite and quartz Raman geobarometers for UHP metamorphic rocks is discussed. PMID:17553735

  17. Saldanha Massif, Mid-Atlantic Ridge: A Controlled Source EM Study

    NASA Astrophysics Data System (ADS)

    Sinha, M. C.; Santos, F.; Dzhatieva, Z.; Dias, A.; Marques, A. F.; Silva, N.; de Nijs, I.

    2005-12-01

    In November-December 2004 a controlled source electromagnetic (CSEM) survey was carried out on the axis of the Mid-Atlantic Ridge during cruise Charles Darwin 167. The work is centred on a non-transform offset between the FAMOUS and AMAR segments, at 36 34' North. Here, a prominent feature is the Saldanha massif: a dome of unroofed mantle rocks, consisting largely of serpentised peridotites, and at whose summit significant low-temperature hydrothermal venting has been documented. Our objective is to determine the distribution of electrical resistivity and hence porosity over a volume of ~ 10 km x 10 km x 3 km vertically, in order to constrain the degree of penetration of seawater into the crust and uppermost mantle; to contrast the porosity structure here with volcanically hosted systems away from segment boundaries elsewhere on the MAR; and to constrain models of non-volcanic heat sources and hydrothermal circulation in ultramafic settings at slow spreading ridges. In addition to the CSEM survey we obtained swath bathymetry, gravity and magnetic data; water column physical properties and seafloor current data; and a number of dredge and gravity core samples. We shall present details of the data and samples, together with our preliminary analysis of the results.

  18. Metamorphic diamonds in a garnet megacryst from the Edough Massif (northeastern Algeria). Recognition and geodynamic consequences

    NASA Astrophysics Data System (ADS)

    Caby, Renaud; Bruguier, Olivier; Fernandez, Laure; Hammor, Dalila; Bosch, Delphine; Mechati, Mehdi; Laouar, Rabah; Ouabadi, Aziouz; Abdallah, Nachida; Douchet, Chantal

    2014-12-01

    We report for the first time the discovery of diamond inclusions (5-30 ?m in size), identified by Raman spectroscopy and the characteristic sharp band at 1332 cm- 1 for crystalline diamond, in a garnet megacryst (? 5 cm) from the Edough Massif (NE Algeria). The garnet is adjacent to actinolite and ultramafic boudins and slices of marbles that are inserted within a major mylonite-ultramylonite band. This tectonic contact sharply delineates the Kef Lakhal oceanic unit from the granite-gneiss core below. The host garnet is almandine-dominant and is rich in exsolution of acicular rutile needles. Major and trace elements show a gradual but significant zonation from core to rim, and a sharp increase in grossular component in the rim. Trace element analyses of prismatic rutile inclusions up to 300 ?m in size indicate that the host metamorphic rock was a mafic protolith of MORB affinity. The Zr-in-rutile thermometry indicates a temperature range of 724-778 C that we relate to rutile growth, either during prograde metamorphism or under peak UHP metamorphic conditions of ? 3.6 GPa that were reached during subduction of the UHP-rock precursors. We suggest that the mafic protolith originates from the subducted retreating Calabrian branch of the Tethyan slab, that broke or tore, and which fragments were dragged upward and thrust onto the North African margin along with the Kef Lakhal unit, shortly followed by formation of the Edough dome and opening of the Algerian basin.

  19. Raman imaging of fluid inclusions in garnet from UHPM rocks (Kokchetav massif, Northern Kazakhstan).

    PubMed

    Korsakov, Andrey V; Dieing, Thomas; Golovin, Aleksandr V; Toporski, Jan

    2011-10-01

    Confocal Raman imaging of fluid inclusions in garnet porphyroblasts from diamond-grade metamorphic calc-silicate rocks from the Kumdy-Kol microdiamond deposit (Kokchetav Massif, Northern Kazakhstan) reveals that these fluid inclusions consist of almost pure water with different step-daughter phases (e.g., calcite, mica and rare quartz). These fluid inclusions are characterized by negative crystal shape of the host-garnet and they exclusively occur within the core of garnet porphyroblasts. These observations are consistent with their primary origin, most likely at ultrahigh-pressure (UHP) metamorphic conditions. The euhedral newly formed garnet, different in color and composition, was found to be associated with these fluid inclusions. It is proposed that newly formed garnet and water fluid inclusions appear by reaction between the hydrous fluid and the garnet-host. These fluid inclusions provide an unequivocal record of almost pure H(2)O fluids, indicating water-saturated conditions within subducted continental crust during prograde stage and/or ultrahigh-P metamorphism. PMID:21377920

  20. Geologic implications of seafloor character and carbonate lithification imaged on the domal core of Atlantis Massif

    NASA Astrophysics Data System (ADS)

    Greene, John A.; Tominaga, Masako; Blackman, Donna K.

    2015-11-01

    We document the seafloor character on Atlantis Massif, an ocean core complex located at 30°N on the Mid-Atlantic Ridge, with an emphasis on the distribution of carbonate features. Seafloor imagery, near-bottom backscatter, and bathymetry were analyzed on the Central Dome and the Western Shoulder of the exposed footwall to the detachment, and on the Eastern Block, a hanging wall to the fault. We merged Argo II still images to produce photo-mosaics and evaluated these together with video imagery, acoustic reflectivity, and basic rock composition. The seafloor was classified as unconsolidated sediment, lithified carbonate crust, consolidated carbonate cap, exposed basement, or rubble, and the spatial distribution of each type was assessed. Unconsolidated sediment, exposed basement, and rubble were documented in all three regions studied. Lithified carbonate crust was also present on the Western Shoulder and eastern Central Dome. Consolidated carbonate cap was found on the Eastern Block. The formation of the carbonate rock is interpreted to reflect precipitation and/or sediment cementation via fluids derived from serpentinization. Both processes occur at the nearby Lost City Hydrothermal Field. The newly documented locations of seafloor carbonate lithification therefore mark pathways of past, possibly recent, fluid flux from subsurface water-rock reaction zones and represent an additional constituent of the carbon cycling hosted by oceanic lithosphere.

  1. Determination of the source rocks for the diatexites from the Edough Massif, Annaba, NE Algeria

    NASA Astrophysics Data System (ADS)

    Hadj Zobir, Soraya; Mocek, Beate

    2012-07-01

    The crystalline Edough Massif is located in the oriental part of the Algerian coastline. It consists of two tectonically superposed units of gneisses, augen-gneisses and migmatitic gneisses in the lower unit and micaschists in the upper unit. The crystalline rocks underwent a low to moderate degree of metamorphism; the gneisses suffered partial melting. They display migmatitic features such as nebulitic structures with contorted leucosome layers and K-feldspar porphyroblasts and thus can be classified as diatexites. The mineralogical composition of these rocks is very homogenous and consists of K-feldspar, micas and quartz. The feldspar-rich, arkosic nature of the outcrop implies a granitic source rock. High K2O/Na2O ratios and high A/CNK > 1.1 indicate an S-type granite source and a peraluminous composition of the protolith respectively. Chondrite normalized REE distribution patterns of the Edough diatexites show gently inclined patterns with a minor negative Eu anomaly (Eu/Eu* = 0.36-0.49), which points to a very slightly differentiated granitic source. The REE pattern and trace element data of the diatexites are similar to those of average Proterozoic upper continental crust, which suggests that they are derived mainly from upper continental crust and were deposited in continental margins.

  2. The limnology and biology of the Dufek Massif, Transantarctic Mountains 82 South

    NASA Astrophysics Data System (ADS)

    Hodgson, Dominic A.; Convey, Peter; Verleyen, Elie; Vyverman, Wim; McInnes, Sandra J.; Sands, Chester J.; Fernndez-Carazo, Rafael; Wilmotte, Annick; De Wever, Aaike; Peeters, Karolien; Tavernier, Ines; Willems, Anne

    2010-08-01

    Very little is known about the higher latitude inland biology of continental Antarctica. In this paper we describe the limnology and biology of the Dufek Massif, using a range of observational, microscopic and molecular methods. Here two dry valleys are home to some of the southernmost biota on Earth. Cyanobacteria were the dominant life forms, being found in lakes and ponds, in hypersaline brines, summer melt water, relict pond beds and in exposed terrestrial habitats. Their species diversity was the lowest yet observed in Antarctic lakes. Green algae, cercozoa and bacteria were present, but diatoms were absent except for a single valve; likely windblown. Mosses were absent and only one lichen specimen was found. The Metazoa included three microbivorous tardigrades ( Acutuncus antarcticus, Diphascon sanae and Echiniscus (cf) pseudowendti) and bdelloid rotifer species, but no arthropods or nematodes. These simple faunal and floral communities are missing most of the elements normally present at lower latitudes in the Antarctic which is probably a result of the very harsh environmental conditions in the area.

  3. Vorticity analysis in calcite tectonites: An example from the Attico-Cycladic massif (Attica, Greece)

    NASA Astrophysics Data System (ADS)

    Spanos, D.; Xypolias, P.; Koukouvelas, I.

    2015-11-01

    Although calcite tectonites are widespread in nature their use to quantify flow vorticity is limited. We use new (micro-)structural, petrofabric and vorticity data to analyse the kinematics of flow in outcrop-scale calcite mylonite zones. These zones are genetically related to a crustal-scale NE-directed ductile thrust (Basal Thrust) that emplaced the Blueschist over the Basal unit during the exhumation of the Attico-Cycladic Massif. Calcite microstructures reveal that the last stage of deformation occurred at temperatures 200-300C achieved by mild heating, which is possibly related with the reburial of the Basal Thrust's footwall. Vorticity analyses were based on the degree of asymmetry of calcite c-axis fabrics as well as on the assumption that the orientation of the long axes of calcite neoblasts within an oblique foliation delineates the direction of instantaneous stretching axis. Both methodological approaches provide consistent estimates with a simple shear component between 55% and 82% (Wn=0.76-0.96). The use of the stress axis (?1) orientation recorded by twin-c-axis-pairs to quantify vorticity generally gives significantly lower simple shear component. Comparison of our vorticity estimates with previous estimates inferred from quartz fabrics and rigid porphyroclasts reveals that exhumation-related deformation in the nappe pile was steady state.

  4. Timescales of regional circulation of saline fluids in continental crystalline rock aquifers (Armorican Massif, western France)

    NASA Astrophysics Data System (ADS)

    Armandine Les Landes, A.; Aquilina, L.; Davy, P.; Vergnaud-Ayraud, V.; Le Carlier, C.

    2015-03-01

    In recent decades, saline fluids have been sampled worldwide at great depths in continental basements. Although some of them have been attributed to marine transgressions, the mechanisms allowing their circulation are not understood. In this paper, we describe the horizontal and vertical distributions of moderately saline fluids (60 to 1400 mg L-1) sampled at depths ranging from 41 to 200 m in crystalline rock aquifers on the regional scale of the Armorican Massif (northwestern France). The horizontal and vertical distributions of high chloride concentrations are in good agreement with both the altitudinal and vertical limits and the succession of the three major transgressions between the Mio-Pliocene and Pleistocene ages. The mean chloride concentration for each transgression area is exponentially related to the time spanned until the present. It defines the potential laws of leaching (displacement) of marine waters by fresh meteoric waters. The results of the Armorican aquifers provide the first observed constraints for the timescales of seawater circulation in the continental crystalline basement and the subsequent leaching by fresh meteoric waters. The general trend of increasing chloride concentration with depth and the time frame for the flushing process provide useful information to develop conceptual models of the paleo-functioning of Armorican aquifers.

  5. Melting and undercooled crystallisation of felsic xenoliths from minor intrusions (Jebilet massif, Morocco)

    NASA Astrophysics Data System (ADS)

    Bouloton, J.; Gasquet, D.

    1995-06-01

    Granitic and gneissic xenoliths within microdiorite dykes from the Palaeozoic Jebilet massif (Morocco) contain up to 40% of granophyric intergrowths that occur as films along quartz-feldspar contacts and form an interconnected grain boundary network. The composition of the feldspar megacrysts i.e. large embayed crystals surrounded by the granophyric intergrowths implies high-temperature crystallisation ( T >900 C) and the sievetexture (or finger-print texture) indicates that these crystals underwent incipient melting. Moreover, the microstructural position and bulk composition of the granophyre are similar to that of glass in partly molten felsic xenoliths from lavas or pyroclastics. It is argued that the granophyre originated after partial melting of the xenoliths when incorporated into the dioritic magma. Crystallisation of that melt resulted in most cases in the formation of vermicular and/or cuneiform granophyre, which testifies to moderate degrees of undercooling. A few occurrences of plumose granophyre i.e. very thin intergrowths that are close to quartz-bearing spherulites, indicate that some xenoliths crystallised at higher degrees of undercooling. Together with granophyric xenoliths, a number of microgranular inclusions also occur. These are characterized by phenocrysts of quartz and feldspar in a microgranular groundmass. Finger-print texture in feldspar suggests that these inclusions, like the granophyric xenoliths, underwent ultra-metamorphism and melting. The microgranular groundmass is most probably indicative of crystallisation at lower degrees of undercooling, but the relationships between the two types of xenoliths still remain to be explored in detail.

  6. IODP Expedition 340T: Borehole Logging at Atlantis Massif Oceanic Core Complex

    NASA Astrophysics Data System (ADS)

    Blackman, D.; Slagle, A.; Harding, A.; Guerin, G.; McCaig, A.

    2013-03-01

    Integrated Ocean Drilling Program (IODP) Expedition 340T returned to the 1.4-km-deep Hole U1309D at Atlantis Massif to carry out borehole logging including vertical seismic profiling (VSP). Seismic, resistivity, and temperature logs were obtained throughout the geologic section in the footwall of this oceanic core complex. Reliable downhole temperature measurements throughout and the first seismic coverage of the 800-1400 meters below seafloor (mbsf) portion of the section were obtained. Distinct changes in velocity, resistivity, and magnetic susceptibility characterize the boundaries of altered, olivine-rich troctolite intervals within the otherwise dominantly gabbroic se-quence. Some narrow fault zones also are associated with downhole resistivity or velocity excursions. Small deviations in temperature were measured in borehole fluid adjacent to known faults at 750 mbsf and 1100 mbsf. This suggests that flow of seawater remains active along these zones of faulting and rock alteration. Vertical seismic profile station coverage at zero offset now extends the full length of the hole, including the uppermost 150 mbsf, where detachment processes are expected to have left their strongest imprint. Analysis of wallrock properties, together with alteration and structural characteristics of the cores from Site U1309, highlights the likely interplay between lithology, structure, lithospheric hydration, and core complex evolution. doi:10.2204/iodp.sd.15.04.2013

  7. Exhumation of high grade rocks in Eastern Bohemian Massif: Insight from analogue and numerical modelling

    NASA Astrophysics Data System (ADS)

    Duretz, T.; Schulmann, K.; Kaus, B. J. P.; Gapais, D.

    2009-04-01

    Recent petrological, structural and geochronological studies of the eastern margin of the Bohemian Massif (Czech Republic) suggest a new conceptual geodynamical model to explain exhumation of high grade (20 kbar, 800C) rocks. This conceptual model involves indentation of a weak orogenic lower crust by adjacent rigid mantle lithosphere, resulting in crustal scale buckling of the weak orogenic lower/middle crust interface followed by extrusion of hot ductile nappes over the rigid promontory. In order to test the hypothesis, we performed both analogue and numerical models. Analogue experiments using a 3 layer sand-silicon setup were carried out in Rennes laboratory (France). Results show that the most important features of the conceptual model can be reproduced providing a sufficient viscosity contrast between the silicones is considered. This involves: periodical buckling of silicones interface, extrusion of lowermost silicon over the indenter and flow of horizontal viscous channel underneath rigid lid above the actively progressing promontory. In addition to the laboratory experiments, we currently perform numerical simulations using the recently developed code MILAMIN_VEP (Kaus, 2008). The first set of numerical experiments are designed to mimic laboratory conditions, i.e. deformation of horizontal layered systems of contrasting viscosities. A second set of experiments are performed on a lithospheric scale, which allows to address the importance of existing temperature variations in Variscan orogenic root systems in terms of temperature dependent rheologies.

  8. The Variscan evolution in the External massifs of the Alps and place in their Variscan framework

    NASA Astrophysics Data System (ADS)

    von Raumer, Jürgen F.; Bussy, François; Stampfli, Gérard M.

    2009-02-01

    In the general discussion on the Variscan evolution of central Europe the pre-Mesozoic basement of the Alps is, in many cases, only included with hesitation. Relatively well-preserved from Alpine metamorphism, the Alpine External massifs can serve as an excellent example of evolution of the Variscan basement, including the earliest Gondwana-derived microcontinents with Cadomian relics. Testifying to the evolution at the Gondwana margin, at least since the Cambrian, such pieces took part in the birth of the Rheic Ocean. After the separation of Avalonia, the remaining Gondwana border was continuously transformed through crustal extension with contemporaneous separation of continental blocks composing future Pangea, but the opening of Palaeotethys had only a reduced significance since the Devonian. The Variscan evolution in the External domain is characterised by an early HP-evolution with subsequent granulitic decompression melts. During Visean crustal shortening, the areas of future formation of migmatites and intrusion of monzodioritic magmas in a general strike-slip regime, were probably in a lower plate situation, whereas the so called monometamorphic areas may have been in an upper plate position of the nappe pile. During the Latest Carboniferous, the emplacement of the youngest granites was associated with the strike-slip faulting and crustal extension at lower crustal levels, whereas, at the surface, detrital sediments accumulated in intramontaneous transtensional basins on a strongly eroded surface.

  9. Nature of radioactive contamination of components of ecosystems of streamflows from tunnels of Degelen massif.

    PubMed

    Panitskiy, A V; Lukashenko, S N

    2015-06-01

    The paper provides data on environmental contamination due to radionuclides' migration with water. As a result of investigations there was obtained data on character of contamination of soil cover, surface water and underflow from tunnels of Degelen massif. Character of radionuclides' spatial distribution in environment was also shown. Mobility ranges of radionuclides' vertical and horizontal movements have been established in soils both across and along the stream flow. There was also shown a possibility to forecast radionuclides' concentration in soil by specific activity of these radionuclides in water. Different concentrations of radionuclides in associated components of the ecosystem (surface waters - ground waters - soils) have shown disequilibrium of their condition in this system. Generalization of investigation results for tunnel water streams' with water inflows, chosen as investigation objects in this work, allows to forecast radionuclides' behavior in meadow soils and other ecosystems of water streams from tunnels of Degelen test site. Based on analysis of curves, describing radionuclides' behavior in horizontal direction, we can forecast, that at this stage (137)Cs and (239+240)Pu would not be distributed more than 1.5km from the access to the daylight surface, (90)Sr - not more than 2km. PMID:25791901

  10. Adjusting stream-sediment geochemical maps in the Austrian Bohemian Massif by analysis of variance

    USGS Publications Warehouse

    Davis, J.C.; Hausberger, G.; Schermann, O.; Bohling, G.

    1995-01-01

    The Austrian portion of the Bohemian Massif is a Precambrian terrane composed mostly of highly metamorphosed rocks intruded by a series of granitoids that are petrographically similar. Rocks are exposed poorly and the subtle variations in rock type are difficult to map in the field. A detailed geochemical survey of stream sediments in this region has been conducted and included as part of the Geochemischer Atlas der Republik O??sterreich, and the variations in stream sediment composition may help refine the geological interpretation. In an earlier study, multivariate analysis of variance (MANOVA) was applied to the stream-sediment data in order to minimize unwanted sampling variation and emphasize relationships between stream sediments and rock types in sample catchment areas. The estimated coefficients were used successfully to correct for the sampling effects throughout most of the region, but also introduced an overcorrection in some areas that seems to result from consistent but subtle differences in composition of specific rock types. By expanding the model to include an additional factor reflecting the presence of a major tectonic unit, the Rohrbach block, the overcorrection is removed. This iterative process simultaneously refines both the geochemical map by removing extraneous variation and the geological map by suggesting a more detailed classification of rock types. ?? 1995 International Association for Mathematical Geology.

  11. AMS 14C Dates for Extinct Lemurs from Caves in the Ankarana Massif, Northern Madagascar

    NASA Astrophysics Data System (ADS)

    Simons, Elwyn L.; Burney, David A.; Chatrath, Prithijit S.; Godfrey, Laurie R.; Jungers, William L.; Rakotosamimanana, Berthe

    1995-03-01

    An extensive late Quaternary fauna, including many extinct giant lemurs, has been collected recently in a 110+-km system of caves in the Ankarana Massif of northern Madagascar. AMS 14C dates for the acid-insoluble (collagen/gelatin) fraction of bones of the giant lemur Megaladapis (26,150 400 and 12,760 70 yr B.P.) confirm its presence in the area during the late Pleistocene and provide the first Pleistocene 14 C ages from bones of the extinct megafauna of the island. The first date from bones of the recently described extinct Babakotia radofilai (4400 60 yr B.P.) shows that it was present in northern Madagascar in mid-Holocene times. A comparatively recent age of 1020 50 yr B.P. for the extinct Archaeolemur indicates survival of this genus for at least a millennium after the first direct evidence for humans in Madagascar. This suggests that the island's "extinction window" may have represented a longer time span than would have been expected under the Blitzkrieg model of late Quaternary extinctions. A mid-Holocene age (4560 70 yr B.P.) for a bone sample of the small extant lemur Hapalemur simus indicates that the disappearance of this now-restricted species from the Ankarana occurred after this date. New data from the Ankarana and other sites on the island add to the consensus that major biotic changes occurred on Madagascar in the late Holocene.

  12. Understanding the Tectonic Deformation of Turkish Blocks since Mesozoic; A Paleomagnetic study on the Nigde-Kirsehir Massif and the Taurides

    NASA Astrophysics Data System (ADS)

    Mualla, Cinku; Mumtaz, Hisarli; Ulker, Beyza; Kaya, Nurcan; Oksum, Erdinc; Yilmaz, Yucel; Orbay, Naci

    2015-04-01

    It is reported that the Nigde-Kirsehir massif which constitutes the main fragment of Anatolia is rifted from the Taurides-Anatolides in Mesozoic and that the Intra-Tauride ocean exist between these blocks. Another group of researchers believed that the Intra Tauride ocean did not exist. They assumed that the Nigde-Kirsehir massif existed as a promotory of the Taurides. In this sense, both the Nigde-Kirsehir massif and the Taurides experienced several deformation phases due to the consumption of the oceanic strand (s) and the amalgamation of the Anatolian blocks after collision in the end of the paleotectonic time, whereas in the neotectonic time the traces of the westwards excursion of Anatolia was effective. Previous paleomagnetic studies showed that the Nigde-Kirsehir massif rotated 90° anticlockwise during Jurassic to Eocene time and other studies showed that the collision between the Nigde-Kirsehir massif and the Pontides resulted by deformation which was accomodated by regional faults. In the south of the Nigde-Kirsehir massif, it was proposed that all the rocks in Carboniferous to Eosen were remagnetized due to nap emplacement in Eocene. Because of several alternative interpretations about the tectonic deformation of the Nigde-Kirsehir massif in relation between the Taurides and the Pontides, we report new paleomagnetic results from Late Jurassic to Miocene rocks in the Nigde-Kirsehir massif and its surrounding. A total of 138 different sites were sampled from Jurassic to Miocene rocks in the south of the Nigde-Kirsehir massif around Ki ri kkale, Tuzgölü, Uluki şla and Kayseri, whereas in the Central Taurides Late Jurassic- Lower Cretaceous platform type carbonates and ophiolitic rocks from Mersin and Pozanti were collected. Paleomagnetic results evaluated together with previous paleomagnetic data indicate that all the studied rocks carry a magnetization before folding according to positive incremental fold tests. It has been shown that in the SE/E (SE Taurides) and the SW/W (Central Taurides) area two different sense of rotation occured. In the SE/E area, counterclockwise rotation of 18° took place in the period between Lower Cretaceous-Middle Eocene. The rotations are consistent with the thrust directions, indicating evidence for the consumption of the Intra Tauride ocean in Late Cretaceous. This result was supported by the paleolatitudes obtained for the Taurides and the Niğde Ki rşehir massif which showed a spatial gap of 1000 km between the Pontides and the Taurides in Late Jurassic- Lower Cretaceous and Late Cretaceous. In the SW/W, however, clockwise rotation of 47° between Middle Eocene and Miocene time, imply that the deformation occured in a later phase as a result of consumption of the South Neotethys ocean and the collision between the African and Eurasian plates. Accordingly to the paleomagnetic rotations which took place gradually in the SE/E area in Middle Eocene, it is shown that counterclockwise rotations of 25° took place in the Niğde Ki rşehir massif during Paleocene. This implies that the Nigde-Kirsehir massif underwent similar deformation together with the adjacent block in the SE/E. In the Neotectonic period, counterclockwise rotation of 17° was obtained in the SE/E area. It is shown that the westwards movement of Anatolia affected mainly the SE/E ares despite the SW/W and the Nigde-Kirsehir massif, which show no significant rotations. This study was financially supported by the project of the Scientific and Technical Research Council of Turkey (TUBITAK) with Project number 111Y043.

  13. Lithologic Distribution and Geologic History of the Apollo 17 Site: The Record in Soils and Small Rock Particles from the Highland Massifs

    NASA Technical Reports Server (NTRS)

    Jolliff, Bradley L.; Rockow, Kaylynn M.; Korotev, Randy L.; Haskin, Larry A.

    1996-01-01

    Through analysis by instrumental neutron activation (INAA) of 789 individual lithic fragments from the 2 mm-4 mm grain-size fractions of five Apollo 17 soil samples (72443, 72503, 73243, 76283, and 76503) and petrographic examination of a subset, we have determined the diversity and proportions of rock types recorded within soils from the highland massifs. The distribution of rock types at the site, as recorded by lithic fragments in the soils, is an alternative to the distribution inferred from the limited number of large rock samples. The compositions and proportions of 2 mm-4 mm fragments provide a bridge between compositions of less than 1 mm fines and types and proportions of rocks observed in large collected breccias and their clasts. The 2 mm-4 mm fraction of soil from South Massif, represented by an unbiased set of lithic fragments from station-2 samples 72443 and 72503, consists of 71% noritic impact-melt breccia, 7% Incompatible-Trace-Element-(ITE)-poor highland rock types (mainly granulitic breccias), 19% agglutinates and regolith breccias, 1% high-Ti mare basalt, and 2% others (very-low-Ti (VLT) basalt, monzogabbro breccia, and metal). In contrast, the 2 mm - 4 mm fraction of a soil from the North Massif, represented by an unbiased set of lithic fragments from station-6 sample 76503, has a greater proportion of ITE-poor highland rock types and mare-basalt fragments: it consists of 29% ITE-poor highland rock types (mainly granulitic breccias and troctolitic anorthosite), 25% impact-melt breccia, 13% high-Ti mare basalt, 31 % agglutinates and regolith breccias, 1% orange glass and related breccia, and 1% others. Based on a comparison of mass- weighted mean compositions of the lithic fragments with compositions of soil fines from all Apollo 17 highland stations, differences between the station-2 and station-6 samples are representative of differences between available samples from the two massifs. From the distribution of different rock types and their compositions, we conclude the following: (1) North-Massif and South-Massif soil samples differ significantly in types and proportions of ITE-poor highland components and ITE-rich impact-melt-breccia components. These differences reflect crudely layered massifs and known local geology. The greater percentage of impact-melt breccia in the South- Massif light-mantle soil stems from derivation of the light mantle from the top of the massif, which apparently is richer in noritic impact-melt breccia than are lower parts of the massifs. (2) At station 2, the 2 mm-4 mm grain-size fraction is enriched in impact-melt breccias compared to the less than 1 mm fraction, suggesting that the <1 mm fraction within the light mantle has a greater proportion of lithologies such as granulitic breccias which are more prevalent lower in the massifs and which we infer to be older (pre-basin) highland components. (3) Soil from station 6, North Massif, contains magnesian troctolitic anorthosite, which is a component that is rare in station-2 South-Massif,contains magnesian troctolitic in impact-melt breccia interpreted by most investigators to be ejecta from the Serenitatis basin.

  14. DETAIL OF EAVES AND HOODS OVER WINDOWS ON NORTHEAST END ...

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

    DETAIL OF EAVES AND HOODS OVER WINDOWS ON NORTHEAST END OF NORTHWEST SIDE, WITH SEABEE STATUE IN BACKGROUND. - U.S. Naval Base, Pearl Harbor, Joint Intelligence Center, Makalapa Drive in Makalapa Administration Area, Pearl City, Honolulu County, HI

  15. OBLIQUE OF NORTHEAST END WITH FACILITY 252 PORTION OF BUILDING ...

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

    OBLIQUE OF NORTHEAST END WITH FACILITY 252 PORTION OF BUILDING (FIRST-FLOOR CONCRETE PORTION) IN FOREGROUND. - U.S. Naval Base, Pearl Harbor, Combat Intelligence Center, Makalapa Drive in Makalapa Administration Area, Pearl City, Honolulu County, HI

  16. OBLIQUE SHOWING NORTHEAST END AND NORTHWEST SIDE. FACILITY 252 PORTION ...

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

    OBLIQUE SHOWING NORTHEAST END AND NORTHWEST SIDE. FACILITY 252 PORTION OF BUILDING IS ON LEFT. - U.S. Naval Base, Pearl Harbor, Combat Intelligence Center, Makalapa Drive in Makalapa Administration Area, Pearl City, Honolulu County, HI

  17. OBLIQUE OF THE NORTHEAST END (MAIN ENTRY) AND NORTHWEST SIDE, ...

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

    OBLIQUE OF THE NORTHEAST END (MAIN ENTRY) AND NORTHWEST SIDE, WITH FACILITY 346 ON LEFT. - U.S. Naval Base, Pearl Harbor, Joint Intelligence Center, Makalapa Drive in Makalapa Administration Area, Pearl City, Honolulu County, HI

  18. 31. GENERAL VIEW LOOKING NORTHEAST, SHOWING THE CONSTRUCTION AND FORMWORK ...

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

    31. GENERAL VIEW LOOKING NORTHEAST, SHOWING THE CONSTRUCTION AND FORMWORK FOR THE TURBINE ASSEMBLIES. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  19. 20. GENERAL VIEW OF CONSTRUCTION LOOKING NORTHEAST SHOWING THE CONSTRUCTION ...

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

    20. GENERAL VIEW OF CONSTRUCTION LOOKING NORTHEAST SHOWING THE CONSTRUCTION BRIDGE, GANTRY CRANE AND STRUCTURAL PIERS. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  20. GENERAL VIEW LOOKING NORTHEAST SHOWING THE SWITCHYARD OF THE WILSON ...

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

    GENERAL VIEW LOOKING NORTHEAST SHOWING THE SWITCHYARD OF THE WILSON DAM HYDROELECTRIC GENERATING PLANT. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  1. 22. GENERAL VIEW LOOKING NORTHEAST, SHOWING GANTRY CRANES AND THE ...

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

    22. GENERAL VIEW LOOKING NORTHEAST, SHOWING GANTRY CRANES AND THE SPILLWAY SECTION NEAR COMPLETION. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  2. 32. GENERAL VIEW LOOKING NORTHEAST, SHOWING DRAFT CONES AND INTAKE ...

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

    32. GENERAL VIEW LOOKING NORTHEAST, SHOWING DRAFT CONES AND INTAKE TUBES. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  3. VIEW LOOKING NORTHEAST SHOWING A CORNER DETAIL OF THE POWERHOUSE ...

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

    VIEW LOOKING NORTHEAST SHOWING A CORNER DETAIL OF THE POWERHOUSE AND THE SOUTHERN SECTION OF THE DAM. - Wilson Dam & Hydroelectric Plant, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  4. 2. BUILDING 321. VIEW TO NORTHEAST. Rocky Mountain Arsenal, ...

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

    2. BUILDING 321. VIEW TO NORTHEAST. - Rocky Mountain Arsenal, Boiler Plant-Central Gas Heat Plant, 1022 feet South of December Seventh Avenue; 525 feet West of D Street, Commerce City, Adams County, CO

  5. LIVING ROOM INTERIOR TAKEN FROM FRONT ENTRY. VIEW FACING NORTHEAST. ...

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

    LIVING ROOM INTERIOR TAKEN FROM FRONT ENTRY. VIEW FACING NORTHEAST. - U.S. Naval Base, Pearl Harbor, Naval Housing Area Hospital Point, Quarters for Officer in Charge of Radio Station, 1 Ford Island Way, Pearl City, Honolulu County, HI

  6. EXTERIOR OBLIQUE VIEW FACING FRONT AND SIDE. VIEW FACING NORTHEAST. ...

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

    EXTERIOR OBLIQUE VIEW FACING FRONT AND SIDE. VIEW FACING NORTHEAST. - U.S. Naval Base, Pearl Harbor, Naval Housing Area Hospital Point, Quarters for Officer in Charge of Radio Station, 1 Ford Island Way, Pearl City, Honolulu County, HI

  7. 12. NORTHEAST VIEW OF THE WASTE WATER TREATMENT COMPLEX FOR ...

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

    12. NORTHEAST VIEW OF THE WASTE WATER TREATMENT COMPLEX FOR THE PRIMARY AND 22 BAR MILLS. - U.S. Steel Duquesne Works, Auxiliary Buildings & Shops, Along Monongahela River, Duquesne, Allegheny County, PA

  8. 51. LOOKING NORTHEAST AT EIMCO WASTE WATER TREATMENT THICKENER No. ...

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

    51. LOOKING NORTHEAST AT EIMCO WASTE WATER TREATMENT THICKENER No. 2, ELECTRIC POWERHOUSE No. 2, AND OUTDOOR ELECTRICAL SUBSTATION IN BACKGROUND. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  9. NORTHEAST (SIDE) AND NORTHWEST (REAR) ELEVATIONS OF BUILDING. VIEW TO ...

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

    NORTHEAST (SIDE) AND NORTHWEST (REAR) ELEVATIONS OF BUILDING. VIEW TO SOUTH - Plattsburgh Air Force Base, Industrial Wastewater Treatment & Disposal Facility, Off LeMay Road, outside SAC Alert Area, Plattsburgh, Clinton County, NY

  10. SOUTHEAST (FRONT) AND NORTHEAST (SIDE) ELEVATIONS OF BUILDING. VIEW TO ...

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

    SOUTHEAST (FRONT) AND NORTHEAST (SIDE) ELEVATIONS OF BUILDING. VIEW TO WEST - Plattsburgh Air Force Base, Industrial Wastewater Treatment & Disposal Facility, Off LeMay Road, outside SAC Alert Area, Plattsburgh, Clinton County, NY

  11. Interior view, room 1103 northeast anteroom, general view to show ...

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

    Interior view, room 1103 northeast anteroom, general view to show fireplace and windows - National Park Seminary, Music Hall, Linden Lane at western edge of campus, Silver Spring, Montgomery County, MD

  12. PERSPECTIVE VIEW LOOKING NORTHEAST AT THE TEST STAND, NOTE THE ...

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

    PERSPECTIVE VIEW LOOKING NORTHEAST AT THE TEST STAND, NOTE THE SERVICE AND SUPPORT BUILDINGS TO THE LEFT AND RIGHT OF THE TEST STAND. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

  13. 10. VIEW OF THE BADGER STATE MINEYARD, LOOKING NORTHEAST, SHOWING ...

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

    10. VIEW OF THE BADGER STATE MINEYARD, LOOKING NORTHEAST, SHOWING THE HOIST HOUSE ON THE LEFT, THE IDLER TOWER, AND A LEG OF THE HEADFRAME ON THE RIGHT - Butte Mineyards, Badger State Mine, Butte, Silver Bow County, MT

  14. 1. Distant view of lock and dam to northeast ...

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

    1. Distant view of lock and dam to northeast - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  15. 5. Overview of bay with geared mechanism to northeast ...

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

    5. Overview of bay with geared mechanism to northeast - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  16. 11. Overview of bay with hydraulic mechanism to northeast ...

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

    11. Overview of bay with hydraulic mechanism to northeast - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  17. 14. Overview of bay without sluice gate machinery to northeast ...

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

    14. Overview of bay without sluice gate machinery to northeast - Mississippi River 9-Foot Channel, Lock & Dam No. 1, In Mississippi River at Mississippi Boulevard, below Ford Parkway Bridge, Saint Paul, Ramsey County, MN

  18. PERSPECTIVE VIEW OF LIBRARY IN ENVIRONMENT CONTEXT, LOOKING NORTHEAST FROM ...

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

    PERSPECTIVE VIEW OF LIBRARY IN ENVIRONMENT CONTEXT, LOOKING NORTHEAST FROM THE ROOF OF THE FRANKLIN INSTITUTE - Free Library of Philadelphia, Central Library, 1901 Vine Street, Philadelphia, Philadelphia County, PA

  19. ELEVATION NORTHEAST BY 30 DEGREES, WEST SECTIONS OF SPAN COVERED ...

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

    ELEVATION NORTHEAST BY 30 DEGREES, WEST SECTIONS OF SPAN COVERED BY OVERGROWTH - Honey Run Bridge, Spanning Butte Creek, bypassed section of Honey Run Road (originally Carr Hill Road), Paradise, Butte County, CA

  20. 41. Detail, northeast facade, original door from platform to waiting ...

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

    41. Detail, northeast facade, original door from platform to waiting room, now non-functional, view to southwest, 90mm lens; compare with CA-2278-13. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  1. 20. Detail, of tower, northeast facade, showing condition of skirt ...

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

    20. Detail, of tower, northeast facade, showing condition of skirt roof, windows, truncated chimney, dentil course, view to northwest from lift-bed truck, 65mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  2. 1. GENERAL VIEW, FROM NORTHEAST. FRONT FACES EAST. Photocopied from ...

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

    1. GENERAL VIEW, FROM NORTHEAST. FRONT FACES EAST. Photocopied from photograph taken August 4, 1965 by Jack Crosby of the Michigan Historical Commission - Hotel Williams, Log Building No. 4, Murray Bay, Munising, Alger County, MI

  3. 1. GENERAL VIEW, FROM NORTHEAST. FRONT (with screened porch) FACES ...

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

    1. GENERAL VIEW, FROM NORTHEAST. FRONT (with screened porch) FACES EAST. Photocopied from photograph taken August 4, 1965 by Jack Crosby of the Michigan Historical Commission. - Hotel Williams, Williams Log House, Murray Bay, Munising, Alger County, MI

  4. 3. NORTHEAST SIDE, WITH A SINGLE BULLET GLASS WINDOW AND ...

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

    3. NORTHEAST SIDE, WITH A SINGLE BULLET GLASS WINDOW AND SOUTHEAST REAR WITH ENTRY DOOR. - Edwards Air Force Base, South Base Sled Track, Observation Block House, Station "O" area, east end of Sled Track, Lancaster, Los Angeles County, CA

  5. 18. EASTERNMOST 12FOOT CAMERA TOWER. Looking northeast. Edwards Air ...

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

    18. EASTERNMOST 12-FOOT CAMERA TOWER. Looking northeast. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  6. 18. DETAIL VIEW SHOWING MASSIVE TRUCK ASSEMBLY AT NORTHEAST CORNER ...

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

    18. DETAIL VIEW SHOWING MASSIVE TRUCK ASSEMBLY AT NORTHEAST CORNER OF STRUCTURE WITH DOUBLE RAILROAD TRACK; VIEW TO WEST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28417, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  7. 1. John N. Vogel, Photographer, June 2000 View to northeast. ...

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

    1. John N. Vogel, Photographer, June 2000 View to northeast. General view of emergency dam steam plant and hoists. - St. Mary's Falls Canal, Soo Locks, Emergency Dam Steam Plant, St. Mary's River at Falls, Sault Ste. Marie, Chippewa County, MI

  8. Interior, looking northeast Beale Air Force Base, Perimeter Acquisition ...

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

    Interior, looking northeast - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Emergency Generator Enclosure, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

  9. 5. VIEW OF SOUTHEAST AND NORTHEAST ELEVATIONS, SHOWING BRIDGE TO ...

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

    5. VIEW OF SOUTHEAST AND NORTHEAST ELEVATIONS, SHOWING BRIDGE TO NAPPING BUILDING AT LEFT AND STEEL I-BEAM HOIST ON ROOF WITH PARAPET, LOOKING WEST - Massachusetts Mills, Cloth Room-Section 15, 95 Bridge Street, Lowell, Middlesex County, MA

  10. 8. JAMESTOWN ISLAND LOOP ROAD, VIEW TO NORTHEAST OF WINE ...

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

    8. JAMESTOWN ISLAND LOOP ROAD, VIEW TO NORTHEAST OF WINE MAKING SIGN (STOP 5). NOTE WICKET MADE OF VINES IN FOREGROUND. - Jamestown Island Loop Road, Jamestown Island, Jamestown, James City County, VA

  11. 4. DOWNSTREAM ELEVATION. DETAIL OF BUTTRESS ADDITION ON NORTHEAST WING ...

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

    4. DOWNSTREAM ELEVATION. DETAIL OF BUTTRESS ADDITION ON NORTHEAST WING WALL. - Core Creek County Bridge, Spanning Core Creek, approximately 1 mile South of State Route 332 (Newtown Bypass), Newtown, Bucks County, PA

  12. INTERIOR TOWER ROOM LOOKING NORTHEAST. Oregon Inlet Coast Guard ...

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

    INTERIOR TOWER ROOM LOOKING NORTHEAST. - Oregon Inlet Coast Guard Station, Northern end of Pea Island, East side of State Road 1257, 0.3 mile North of North Carolina Highway 12, Rodanthe, Dare County, NC

  13. 44. NORTHEAST VIEW OF IRON DESULPHERIZATION BUILDING, WITH CALCIUM CARBIDE ...

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

    44. NORTHEAST VIEW OF IRON DESULPHERIZATION BUILDING, WITH CALCIUM CARBIDE SILO ADJACENT TO BUILDING ON RIGHT. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  14. 17. NORTHEAST CORNER OF BUILDING 345 (ENTRY CONTROL BUILDING) IN ...

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

    17. NORTHEAST CORNER OF BUILDING 345 (ENTRY CONTROL BUILDING) IN STORAGE AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

  15. Building 904, oblique view to northeast, 210mm lens Travis ...

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

    Building 904, oblique view to northeast, 210mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  16. 13. INTERIOR OF NORTHEAST PHOTO TOWER WITH WINDOW OPEN; ELECTRICAL ...

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

    13. INTERIOR OF NORTHEAST PHOTO TOWER WITH WINDOW OPEN; ELECTRICAL POWER BOX BELOW WINDOW - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  17. BATHROOM OFF BEDROOM AT NORTHEAST CORNER OF GROUND FLOOR, NORTH ...

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

    BATHROOM OFF BEDROOM AT NORTHEAST CORNER OF GROUND FLOOR, NORTH WING. SHOWERS STAND SEPARATELY FROM BATHTUBS IN FACILITY NO. 299 - Hamilton Field, Base Commander's Quarters, 299 Casa Grande Real, Novato, Marin County, CA

  18. 15. Detail, cracks evidencing structural failure, northeast rear, view to ...

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

    15. Detail, cracks evidencing structural failure, northeast rear, view to southwest, 90mm lens. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  19. 12. Detail, typical window with fireproof shutters open, northeast rear, ...

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

    12. Detail, typical window with fireproof shutters open, northeast rear, view to southwest, 135mm lens. Note cracks evidencing structural failure. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  20. 13. Detail, typical window with fireproof shutters closed, northeast rear, ...

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

    13. Detail, typical window with fireproof shutters closed, northeast rear, view to southwest, 135mm lens. Note cracks evidencing structural failure. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  1. 14. Detail, crack evidencing structural failure, northeast rear, view to ...

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

    14. Detail, crack evidencing structural failure, northeast rear, view to southwest, 90mm lens. Note failure of sandstone lintel above window. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  2. FIRST FLOOR, A view from the northeast corner of the ...

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

    FIRST FLOOR, A view from the northeast corner of the clean room (Room 54) looking southwest - Department of Energy, Mound Facility, Isolated Building (I Building), One Mound Road, Miamisburg, Montgomery County, OH

  3. BASEMENT, A view looking northeast that captures the storage lockers ...

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

    BASEMENT, A view looking northeast that captures the storage lockers in the woman's side of the change room (Room 119A) - Department of Energy, Mound Facility, Isolated Building (I Building), One Mound Road, Miamisburg, Montgomery County, OH

  4. 2. SOUTH (AIR SIDE) AND SOUTHWEST ELEVATIONS, LOOKING NORTHEAST FROM ...

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

    2. SOUTH (AIR SIDE) AND SOUTHWEST ELEVATIONS, LOOKING NORTH-EAST FROM BUILDING 340 ROOF. PARKING LOT G IN FOREGROUND. - Newark International Airport, Administration Building, Brewster Road between Route 21 & New Jersey Turnpike Exchange No. 14, Newark, Essex County, NJ

  5. 66. SOUTH PLANT CHEMICAL STORAGE TANKS. VIEW TO NORTHEAST. ...

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

    66. SOUTH PLANT CHEMICAL STORAGE TANKS. VIEW TO NORTHEAST. - Rocky Mountain Arsenal, Bounded by Ninety-sixth Avenue & Fifty-sixth Avenue, Buckley Road, Quebec Street & Colorado Highway 2, Commerce City, Adams County, CO

  6. 3. Oblique view of front (northwest) and left side (northeast) ...

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

    3. Oblique view of front (northwest) and left side (northeast) elevations, looking south. - Downtown Short Pump Grocery, West Broad Street (State Route 250) & Three Chopt Road, Short Pump, Henrico County, VA

  7. OBLIQUE VIEW OF THE NORTHEAST SIDE AND THE SOUTHEAST END ...

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

    OBLIQUE VIEW OF THE NORTHEAST SIDE AND THE SOUTHEAST END OF FACILITY S 633. VIEW FACING WEST. - U.S. Naval Base, Pearl Harbor, Bombproof Facilities, Various locations throughout base, Pearl City, Honolulu County, HI

  8. 2. View looking northeast at Dixie Cotton Mill warehouses. Note ...

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

    2. View looking northeast at Dixie Cotton Mill warehouses. Note firestops between sections of the building to prevent fire from spreading. - Dixie Cotton Mill, Warehouses, 710 Greenville Street, La Grange, Troup County, GA

  9. View from southwest to northeast of cooling towers for perimeter ...

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

    View from southwest to northeast of cooling towers for perimeter acquisition radar building and PAR power plant - Stanley R. Mickelsen Safeguard Complex, Cooling Tower, In Limited Access Area, between Service Roads D & A, Nekoma, Cavalier County, ND

  10. Detail view of operator's housing, northeast corner of bascule span ...

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

    Detail view of operator's housing, northeast corner of bascule span - Old Young's Bay Bridge, Spanning Young's Bay at Milepoint 6.89 on Warrenton-Astoria Highway (Highway No. 9), Astoria, Clatsop County, OR

  11. 2. MAGAZINE P, WITH ENTRANCE DOOR IN FOREGROUND, LOOKING NORTHEAST. ...

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

    2. MAGAZINE P, WITH ENTRANCE DOOR IN FOREGROUND, LOOKING NORTHEAST. - NIKE Missile Base C-84, Underground Storage Magazines & Launcher-Loader Assemblies, Easternmost portion of launch area, Barrington, Cook County, IL

  12. EXTERIOR, A view looking northeast at the south and west ...

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

    EXTERIOR, A view looking northeast at the south and west facades of the building and staircase - Department of Energy, Mound Facility, Hydrolysis House Building (HH Building), One Mound Road, Miamisburg, Montgomery County, OH

  13. EXTERIOR, A view looking northeast toward the south elevation and ...

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

    EXTERIOR, A view looking northeast toward the south elevation and stacks of HH Building - Department of Energy, Mound Facility, Hydrolysis House Building (HH Building), One Mound Road, Miamisburg, Montgomery County, OH

  14. 5. Detail view northeast of facade of Armory Street Pump ...

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

    5. Detail view northeast of facade of Armory Street Pump House. - Lake Whitney Water Filtration Plant, Armory Street Pumphouse, North side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  15. 4. Perspective view northeast of Armory Street Pump House. ...

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

    4. Perspective view northeast of Armory Street Pump House. - Lake Whitney Water Filtration Plant, Armory Street Pumphouse, North side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  16. 1. West portal of Tunnel 25, contextual view to northeast ...

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

    1. West portal of Tunnel 25, contextual view to northeast from Tunnel 24 (HAER CA-200), 135mm lens. - Central Pacific Transcontinental Railroad, Tunnel No. 25, Milepost 133.09, Applegate, Placer County, CA

  17. 7. SHARP CURVES IN RHODES DITCH NEAR NORTHEAST PART OF ...

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

    7. SHARP CURVES IN RHODES DITCH NEAR NORTHEAST PART OF PROJECT. VIEW TO SOUTHEAST. - Natomas Ditch System, Rhodes Ditch, West of Bidwell Street, north of U.S. Highway 50, Folsom, Sacramento County, CA

  18. 1. GUARD RESIDENCE, GARAGE, NORTHWEST FRONT AND NORTHEAST SIDE LOOKING ...

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

    1. GUARD RESIDENCE, GARAGE, NORTHWEST FRONT AND NORTHEAST SIDE LOOKING SOUTH - Union Ranger District Compound, Garage-Guard Residence, Fronting State Highway 203, at West edge of Union, Union, Union County, OR

  19. 2. RANGERS RESIDENCE, GARAGE, NORTHWEST BACK AND NORTHEAST SIDE, LOOKING ...

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

    2. RANGERS RESIDENCE, GARAGE, NORTHWEST BACK AND NORTHEAST SIDE, LOOKING SOUTH - Union Ranger District Compound, Garage-Rangers Residence, Fronting State Highway 203, at West edge of Union, Union, Union County, OR

  20. 11. Northeast front, dock no. 493. View to west. ...

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

    11. Northeast front, dock no. 493. View to west. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  1. 3. View northeast, west facade of Lake Forest (original Forest ...

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

    3. View northeast, west facade of Lake Forest (original Forest Cottage structure incorporated into renamed structure) - Lake Placid Club, Forest Wing, East side of Mirror Lake Drive, North of State Route 86 & Main, North Elba, Essex County, NY

  2. View from northeast to southwest of PAR site sentry station; ...

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

    View from northeast to southwest of PAR site sentry station; formerly the bachelor's enlisted men's quarter (BEQ) - Stanley R. Mickelsen Safeguard Complex, Sentry Station, North of Second Avenue & West of Electrical Switch Station No. 2, Nekoma, Cavalier County, ND

  3. 10. LOOKING NORTHEAST AT THE LINDE 400 TONS PER DAY ...

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

    10. LOOKING NORTHEAST AT THE LINDE 400 TONS PER DAY LOW PURITY OXYGEN MAKING PLANT IN THE LOW PURITY BULK OXYGEN BUILDING. - U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  4. 14. VEHICLE STORAGE BUILDING NORTHWEST SIDE AND NORTHEAST REAR. VIEW ...

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

    14. VEHICLE STORAGE BUILDING NORTHWEST SIDE AND NORTHEAST REAR. VIEW TO SOUTHEAST. - Minuteman III ICBM Launch Control Facility November-1, 1.5 miles North of New Raymer & State Highway 14, New Raymer, Weld County, CO

  5. INTERIOR VIEW, WEST WALL OF THE NORTHEAST BED CHAMBER. AN ...

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

    INTERIOR VIEW, WEST WALL OF THE NORTHEAST BED CHAMBER. AN ARCHED BED ALCOVE IS FLANKED BY THE MAIN ROOM DOOR ON THE LEFT AND A CLOSET DOOR ON THE RIGHT - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  6. Perspective view of east facade from northeast National Home ...

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

    Perspective view of east facade from northeast - National Home for Disabled Volunteer Soldiers, Pacific Branch, Main Mental Health Building, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  7. 7. Northeast view interior, air traffic control and landing system ...

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

    7. Northeast view interior, air traffic control and landing system room 25 - Selfridge Field, Building No. 1050, Northwest corner of Doolittle Avenue & D Street; Harrison Township, Mount Clemens, Macomb County, MI

  8. 1. View northeast of front (west) and side (south) of ...

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

    1. View northeast of front (west) and side (south) of building - National Home for Disabled Volunteer Soldiers Western Branch, Ward Memorial Building, Franklin Avenue, southeast of Intersection with Rowland Avenue, Leavenworth, Leavenworth County, KS

  9. 6. DECK #4 TOPSIDE FROM NORTHEAST CORNER END PIECE FOR ...

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

    6. DECK #4 TOPSIDE FROM NORTHEAST CORNER END PIECE FOR ROBOTIC ARM FOR ANCHORING ASTRONAUT FOR MECHANICAL WORK. - Marshall Space Flight Center, Neutral Buoyancy Simulator Facility, Rideout Road, Huntsville, Madison County, AL

  10. 36. VIEW LOOKING NORTHEAST, SHOWING HYPHEN CONNECTOR BETWEEN ENGINE HOUSE ...

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

    36. VIEW LOOKING NORTHEAST, SHOWING HYPHEN CONNECTOR BETWEEN ENGINE HOUSE AND CARETAKER'S COTTAGE (4' x 5' negative) - Fairmount Waterworks, East bank of Schuylkill River, Aquarium Drive, Philadelphia, Philadelphia County, PA

  11. View northeast, oblique contextual view of hoboken rail yard in ...

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

    View northeast, oblique contextual view of hoboken rail yard in immediate background, Manhattan Skyline in distance. - Delaware, Lackawanna & Western Railroad Freight & Rail Yard, Long Slip Canal, New Jersey Transit Hoboken Rail Yard, Hoboken, Hudson County, NJ

  12. 19. PHOTOCOPY OF c. 1920 VIEW LOOKING NORTHEAST. COURTESY OF ...

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

    19. PHOTOCOPY OF c. 1920 VIEW LOOKING NORTHEAST. COURTESY OF GWENDOLYN G. de CLAIRVILLE, HUNTINGTON, WEST VIRGINIA 11743 - Lefferts Tide Mill, Huntington Harbor, Southdown Road, Huntington, Suffolk County, NY

  13. 17. GENERAL VIEW, LOOKING NORTHEAST TO SOUTHWEST, SHOWING RELATIONSHIP OF ...

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

    17. GENERAL VIEW, LOOKING NORTHEAST TO SOUTHWEST, SHOWING RELATIONSHIP OF TRUSS TO COLUMNS AND BAYS - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  14. 1. GENERAL VIEW SHOWING NORTHEAST END (FRONT) OF TRANSIT SHED, ...

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

    1. GENERAL VIEW SHOWING NORTHEAST END (FRONT) OF TRANSIT SHED, IN CONTEXT WITH LOADING YARD AND DERRICK, LOOKING WEST - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  15. 18. GENERAL VIEW, LOOKING NORTHEAST TO SOUTHWEST, SHOWING RELATIONSHIP TO ...

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

    18. GENERAL VIEW, LOOKING NORTHEAST TO SOUTHWEST, SHOWING RELATIONSHIP TO OFFICE AREA TO STAIRS - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

  16. 6. VIEW SHOWING NORTHEAST END OF WHARF REAR FROM LANDSLIDE ...

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

    6. VIEW SHOWING NORTHEAST END OF WHARF REAR FROM LANDSLIDE - U.S. Naval Base, Pearl Harbor, Berthing Wharf S378, Beckoning Point, Southeast of Cowpens Street, Ford Island, Pearl City, Honolulu County, HI

  17. 4. VIEW TO NORTHEAST, SKINNER SALT ROASTERS, SAMPLING BUILDING, WATER ...

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

    4. VIEW TO NORTHEAST, SKINNER SALT ROASTERS, SAMPLING BUILDING, WATER TOWER, AND OFFICE BUILDING. - Vanadium Corporation of America (VCA) Naturita Mill, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  18. 3. In context, from southwest facing northeast, playground between buildings. ...

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

    3. In context, from southwest facing northeast, playground between buildings. Building 12-A on right, Building 12-B on left. - Clark Howell Homes, Building 12-A, 500 Lovejoy Street, Atlanta, Fulton County, GA

  19. 3. In context, from southwest facing northeast, playground between buildings. ...

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

    3. In context, from southwest facing northeast, playground between buildings. Building 12-A, right, Building 12-A, left. - Clark Howell Homes, Building 12-B, 516 Lovejoy Street, Atlanta, Fulton County, GA

  20. VIEW, LOOKING NORTHEAST, OF CHEMISTRY LAB, LOCATED ON MEZZANINE ABOVE ...

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

    VIEW, LOOKING NORTHEAST, OF CHEMISTRY LAB, LOCATED ON MEZZANINE ABOVE AND EAST OF FLOTATION CELLS. MAIN USE WAS SAMPLE ANALYSIS TO DETERMINE OPTIMUM REAGENT MIXES AND QUANTITIES. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  1. 14. September 20, 1950, source not known VIEW NORTHEAST, SOUTH ...

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

    14. September 20, 1950, source not known VIEW NORTHEAST, SOUTH ELEVATIONS, MECHANICS SAVINGS BANK AND ADJOINING BUILDING TO EAST - Mechanics Savings Bank Building, 80 Pearl Street, Hartford, Hartford County, CT

  2. INTERIOR VIEW, LOOKING NORTHEAST, WITH OVENS (LEFT) AND SLAB BEING ...

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

    INTERIOR VIEW, LOOKING NORTHEAST, WITH OVENS (LEFT) AND SLAB BEING PROCESSED THROUGH PRESS/STECKLER (RIGHT). - Central Iron Foundry, Hot Strip Mill Building, 1700 Holt Road, Holt, Tuscaloosa County, AL

  3. 1. HOUSE, VIEW TO NORTHEAST, SUMMER KITCHEN AND SMOKE HOUSE ...

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

    1. HOUSE, VIEW TO NORTHEAST, SUMMER KITCHEN AND SMOKE HOUSE ARE IN THE BACKGROUND - Kiel Farmstead, House, East side State Route 4, one half mile south of U.S. Route 64, Mascoutah, St. Clair County, IL

  4. Detail view looking northeast at ramp 3. View shows remaining ...

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

    Detail view looking northeast at ramp 3. View shows remaining stone inlay to provide traction surface. - Naval Air Station North Island, Seaplane Ramps Nos. 2, 3 & 4, North Island, San Diego, San Diego County, CA

  5. 1. VIEW NORTHEAST, LEFT TO RIGHT COLD CALIBRATION TEST STAND ...

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

    1. VIEW NORTHEAST, LEFT TO RIGHT COLD CALIBRATION TEST STAND COLD CALIBRATION BLOCKHOUSE IN FOREGROUND. - Marshall Space Flight Center, East Test Area, Cold Calibration Test Stand, Huntsville, Madison County, AL

  6. 29. INTERIOR VIEW TO THE NORTHEAST OF CONTROL PANEL AND ...

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

    29. INTERIOR VIEW TO THE NORTHEAST OF CONTROL PANEL AND VIEWING WINDOW IN ROOM 105, THE CONTROL ROOM. - Nevada Test Site, Pluto Facility, Disassembly Building, Area 26, Wahmonie Flats, Cane Spring Road, Mercury, Nye County, NV

  7. 1. EXTERIOR VIEW TO THE NORTHEAST OF A BROCK HOUSE ...

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

    1. EXTERIOR VIEW TO THE NORTHEAST OF A BROCK HOUSE USED FOR THE WATER FILTERING SYSTEM. - Nevada Test Site, Pluto Facility, Water Filtering System Brock House, Area 26, Wahmonie Flats, Cane Spring Road, Mercury, Nye County, NV

  8. 3. EXTERIOR VIEW TO THE NORTHEAST OF A RAILROAD CAR ...

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

    3. EXTERIOR VIEW TO THE NORTHEAST OF A RAILROAD CAR ON THE TRACKS AND THE PARTS OF AN ENGINE STAND. - Nevada Test Site, Pluto Facility, Area 26, Wahmonie Flats, Cane Spring Road, Mercury, Nye County, NV

  9. 16. INTERIOR VIEW TO THE NORTHEAST OF ROOM 107, THE ...

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

    16. INTERIOR VIEW TO THE NORTHEAST OF ROOM 107, THE HOT STORAGE AND PACKAGING ROOM. - Nevada Test Site, Pluto Facility, Disassembly Building, Area 26, Wahmonie Flats, Cane Spring Road, Mercury, Nye County, NV

  10. 1. Keeper's house, light tower and bell house, view northeast, ...

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

    1. Keeper's house, light tower and bell house, view northeast, northwest and southwest sides - Burnt Coat Harbor Light Station, At Hackamock Head on Swan's Island opposite Harbor Island at entrance to Burnt Coat Harbor, Swans Island, Hancock County, ME

  11. 8. Bell house, view southwest, southeast side and northeast front ...

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

    8. Bell house, view southwest, southeast side and northeast front - Burnt Coat Harbor Light Station, At Hackamock Head on Swan's Island opposite Harbor Island at entrance to Burnt Coat Harbor, Swans Island, Hancock County, ME

  12. FACILITY 847, NORTHWEST END AND NORTHEAST SIDE, QUADRANGLE J, OBLIQUE ...

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

    FACILITY 847, NORTHWEST END AND NORTHEAST SIDE, QUADRANGLE J, OBLIQUE VIEW FACING SOUTH-SOUTH-SOUTHEAST. - Schofield Barracks Military Reservation, Quadrangles I & J Barracks Type, Between Wright-Smith & Capron Avenues near Williston Avenue, Wahiawa, Honolulu County, HI

  13. 11. General interior elevation viewed from midspan toward the northeast, ...

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

    11. General interior elevation viewed from midspan toward the northeast, showing the corrugated metal barriers on both sides and the asphalt deck. - Post Road Bridge, State Route 7-A, Havre de Grace, Harford County, MD

  14. 1. INTAKE CHANNEL LOOKING NORTHEAST; WATER FROM BEAVER BROOK ENTERS ...

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

    1. INTAKE CHANNEL LOOKING NORTHEAST; WATER FROM BEAVER BROOK ENTERS THE INTAKE CHANNEL HERE. - Hondius Water Line, 1.6 miles Northwest of Park headquarters building & 1 mile Northwest of Beaver Meadows entrance station, Estes Park, Larimer County, CO

  15. 13. SETTLING TANK, OVERFLOW DITCH, NORTHEAST SIDE; OVERFLOW DITCH RETURNED ...

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

    13. SETTLING TANK, OVERFLOW DITCH, NORTHEAST SIDE; OVERFLOW DITCH RETURNED EXCESS WATER TO BEAVER BROOK. - Hondius Water Line, 1.6 miles Northwest of Park headquarters building & 1 mile Northwest of Beaver Meadows entrance station, Estes Park, Larimer County, CO

  16. Perspective view toward east, northeast from Line Street showing west ...

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

    Perspective view toward east, northeast from Line Street showing west front and south end - University of Idaho, University Classroom Building, Line Street between University Avenue & Idaho Avenue, Moscow, Latah County, ID

  17. View of camera station located northeast of Building 70022, facing ...

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

    View of camera station located northeast of Building 70022, facing northwest - Naval Ordnance Test Station Inyokern, Randsburg Wash Facility Target Test Towers, Tower Road, China Lake, Kern County, CA

  18. 7. GROUND FLOOR, NORTHEAST PARLOR, LOOKING TOWARD EAST WALL, VIEW ...

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

    7. GROUND FLOOR, NORTHEAST PARLOR, LOOKING TOWARD EAST WALL, VIEW SHOWING WOODEN FLOORBOARDS, FIREPLACE AND MANTEL, OVERMANTEL, CORNICE AND PILASTER STRIPS AND FURNISHINGS - Clover Fields, Forman's Lodge Road, Wye Mills, Talbot County, MD

  19. 2. OBLIQUE VIEW TO NORTHEAST ALONG FRONT OF SANTA ANA ...

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

    2. OBLIQUE VIEW TO NORTHEAST ALONG FRONT OF SANTA ANA RIVER DIVERSION DAM. NOTE CABLE CAR SUSPENSION CABLE AT GATE ATOP DAM. - Santa Ana River Hydroelectric System, Santa Ana River Diversion Dam, Redlands, San Bernardino County, CA

  20. LOOKING NORTHEAST AT FOUNDRY BUILDING. CLOSED DOORS ON LEFT ARE ...

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

    LOOKING NORTHEAST AT FOUNDRY BUILDING. CLOSED DOORS ON LEFT ARE TO MACHINE SHOP, LARGE OPEN DOOR TO THE FOUNDRY, AND THE SMALL OPEN DOOR ON RIGHT TO CORE ROOM. - Knight Foundry, 13 Eureka Street, Sutter Creek, Amador County, CA

  1. 22. LOOKING NORTHEAST AT FOUNDRY BUILDING. CLOSED DOORS ON LEFT ...

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

    22. LOOKING NORTHEAST AT FOUNDRY BUILDING. CLOSED DOORS ON LEFT ARE TO MACHINE SHOP, LARGE OPEN DOOR TO THE FOUNDRY, AND THE SMALL OPEN DOOR ON RIGHT TO CORE ROOM. - Knight Foundry, 13 Eureka Street, Sutter Creek, Amador County, CA

  2. 20. DETAIL WITH FIRE HYDRANT, LOOKING NORTHEAST Kodiak Naval ...

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

    20. DETAIL WITH FIRE HYDRANT, LOOKING NORTHEAST - Kodiak Naval Operating Base, Aircraft Storehouse, U.S. Coast Guard Station, Albatross Avenue near Cape Spencer Street, Kodiak, Kodiak Island Borough, AK

  3. 8. VIEW OF FRONT ELEVATION, BUILDING 2, FACING NORTHEAST. ...

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

    8. VIEW OF FRONT ELEVATION, BUILDING 2, FACING NORTHEAST. - New Orleans City Railroad Company, Canal Station, Square 365, bounded by Canal, North Dupre, Iberville, & North White Streets, New Orleans, Orleans Parish, LA

  4. 13. INTERIOR VIEW OF BUILDING 1, FACING NORTHEAST. New ...

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

    13. INTERIOR VIEW OF BUILDING 1, FACING NORTHEAST. - New Orleans City Railroad Company, Canal Station, Square 365, bounded by Canal, North Dupre, Iberville, & North White Streets, New Orleans, Orleans Parish, LA

  5. 22. INTERIOR VIEW OF BUILDING 2, FACING NORTHEAST. New ...

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

    22. INTERIOR VIEW OF BUILDING 2, FACING NORTHEAST. - New Orleans City Railroad Company, Canal Station, Square 365, bounded by Canal, North Dupre, Iberville, & North White Streets, New Orleans, Orleans Parish, LA

  6. 2. VIEW OF FRONT ELEVATION, CANAL STATION COMPLEX, FACING NORTHEAST ...

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

    2. VIEW OF FRONT ELEVATION, CANAL STATION COMPLEX, FACING NORTHEAST - New Orleans City Railroad Company, Canal Station, Square 365, bounded by Canal, North Dupre, Iberville, & North White Streets, New Orleans, Orleans Parish, LA

  7. 7. VIEW OF FRONT ELEVATION CONCRETE BLOCK SCREEN, FACING NORTHEAST. ...

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

    7. VIEW OF FRONT ELEVATION CONCRETE BLOCK SCREEN, FACING NORTHEAST. - New Orleans City Railroad Company, Canal Station, Square 365, bounded by Canal, North Dupre, Iberville, & North White Streets, New Orleans, Orleans Parish, LA

  8. 6. VIEW OF FRONT ELEVATION, BUILDING 1, FACING NORTHEAST. ...

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

    6. VIEW OF FRONT ELEVATION, BUILDING 1, FACING NORTHEAST. - New Orleans City Railroad Company, Canal Station, Square 365, bounded by Canal, North Dupre, Iberville, & North White Streets, New Orleans, Orleans Parish, LA

  9. DETAIL TOP VIEW OF AERIAL TRAMWAY DRIVE MECHANISM, LOOKING NORTHEAST. ...

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

    DETAIL TOP VIEW OF AERIAL TRAMWAY DRIVE MECHANISM, LOOKING NORTHEAST. THE FRICTION BRAKING SYSTEM CAN BE SEEN IN SHADOW ABOVE THE LARGE CABLE WHEEL BELOW. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

  10. 58. NORTHEAST SIDE ELEVATION OF BUILDING 370 (ADMINISTRATIVE OFFICE BUILDING) ...

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

    58. NORTHEAST SIDE ELEVATION OF BUILDING 370 (ADMINISTRATIVE OFFICE BUILDING) IN BASE SPARES AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

  11. 32. NORTHEAST CORNER OF BUILDING 232 (MINE SHOP) IN ASSEMBLY ...

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

    32. NORTHEAST CORNER OF BUILDING 232 (MINE SHOP) IN ASSEMBLY AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

  12. 49. NORTHEAST FRONT ELEVATION OF BUILDING 365 (ARMAMENT TESTING BUILDING) ...

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

    49. NORTHEAST FRONT ELEVATION OF BUILDING 365 (ARMAMENT TESTING BUILDING) IN BASE SPARES AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

  13. OBLIQUE VIEW OF NORTHWEST AND NORTHEAST SIDES OF HYDROELECTRIC POWER ...

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

    OBLIQUE VIEW OF NORTHWEST AND NORTHEAST SIDES OF HYDROELECTRIC POWER HOUSE, OLD BYPASS IN BACKGROUND, VIEW TOWARDS SOUTH - St. Lucie Canal, Lock No. 1, Hydroelectric Power House, St. Lucie, Cross State Canal, Okeechobee Intracoastal Waterway, Stuart, Martin County, FL

  14. OBLIQUE VIEW OF NORTHEAST AND SOUTHEAST SIDES OF HYDROELECTRIC POWER ...

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

    OBLIQUE VIEW OF NORTHEAST AND SOUTHEAST SIDES OF HYDROELECTRIC POWER HOUSE, VIEW TOWARDS WEST - St. Lucie Canal, Lock No. 1, Hydroelectric Power House, St. Lucie, Cross State Canal, Okeechobee Intracoastal Waterway, Stuart, Martin County, FL

  15. 2. Contextual view looking east, northeast, showing west elevation of ...

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

    2. Contextual view looking east, northeast, showing west elevation of Packing House and Union Ice building. - College Heights Lemon Packing House, 519-532 West First Street, Claremont, Los Angeles County, CA

  16. 8. NORTHEAST CORNER OF ORIGINAL MILL WITH SMALL ADDITIONS AND ...

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

    8. NORTHEAST CORNER OF ORIGINAL MILL WITH SMALL ADDITIONS AND OUTBUILDINGS. NOTE ORIGINAL DUST CHIMNEY ON RIGHT AND WATER TOWER ON LEFT. - Selma Cotton Mill, 218 Morgan Avenue, Selma, Dallas County, AL

  17. 10. NORTHEAST CORNER CONSTRUCTION DETAIL, VIEW OF SIDEWALK. TAMARACK BRIDGE ...

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

    10. NORTHEAST CORNER CONSTRUCTION DETAIL, VIEW OF SIDEWALK. TAMARACK BRIDGE IN LEFT REAR. - Cascade Creek Bridge, Spanning Cascade Creek on New Big Oak Flat Road, Yosemite Village, Mariposa County, CA

  18. SOUTHEAST (SIDE) AND NORTHEAST (REAR) ELEVATIONS OF BUILDING. VIEW TO ...

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

    SOUTHEAST (SIDE) AND NORTHEAST (REAR) ELEVATIONS OF BUILDING. VIEW TO NORTHWEST - Plattsburgh Air Force Base, Composite Medical Facility, New York Road, south of Route 9 Intersection, Plattsburgh, Clinton County, NY

  19. VIEW LOOKING NORTHEAST AT EARTH MOUND. NOTE THE RECTANGULAR OPENINGS ...

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

    VIEW LOOKING NORTHEAST AT EARTH MOUND. NOTE THE RECTANGULAR OPENINGS USED FOR OBSERVATION EQUIPMENT AND PERISCOPE TOPS. - Marshall Space Flight Center, Redstone Rocket (Missile) Test Stand, Dodd Road, Huntsville, Madison County, AL

  20. 15. SOUTHEAST AND NORTHEAST WALLS OF CREW SHELTER LOCATED BETWEEN ...

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

    15. SOUTHEAST AND NORTHEAST WALLS OF CREW SHELTER LOCATED BETWEEN THE PURSUIT PLANE BAYS OF AR-9. - Edwards Air Force Base, South Base, Rammed Earth Aircraft Dispersal Revetments, Western Shore of Rogers Dry Lake, Boron, Kern County, CA

  1. 4. PERSPECTIVE VIEW TO THE NORTHEAST OF THE CREW SHELTER ...

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

    4. PERSPECTIVE VIEW TO THE NORTHEAST OF THE CREW SHELTER IN AR-8. - Edwards Air Force Base, South Base, Rammed Earth Aircraft Dispersal Revetments, Western Shore of Rogers Dry Lake, Boron, Kern County, CA

  2. Looking Northeast in Oxide Building at Reactors on Second Floor ...

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

    Looking Northeast in Oxide Building at Reactors on Second Floor Including Reactor One (Left) and Reactor Two (Right) - Hematite Fuel Fabrication Facility, Oxide Building & Oxide Loading Dock, 3300 State Road P, Festus, Jefferson County, MO

  3. OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. GENERATOR ...

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

    OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. GENERATOR BUILDING TOP LEFT, OFFICE AND STOREROOM TOP CENTER, ROTARY KILN AND CONDENSER PLATFORM RIGHT. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  4. 35. OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. ...

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

    35. OVERHEAD VIEW OF VIVIANNA WORKS ORE BIN LOOKING NORTHEAST. GENERATOR BUILDING TOP LEFT, OFFICE AND STOREROOM TOP CENTER, ROTARY KILN AND CONDENSER PLATFORM RIGHT. - Mariscal Quicksilver Mine & Reduction Works, Terlingua, Brewster County, TX

  5. 5. VIEW OF GENERAL REFRACTORIES COMPANY (GREFCO) HOUSES, NORTHEAST SIDE ...

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

    5. VIEW OF GENERAL REFRACTORIES COMPANY (GREFCO) HOUSES, NORTHEAST SIDE OF PENNSYLVANIA AVENUE LOOKING NORTH. HOUSE NO. 77 AT RIGHT. - Town of Mount Union, Near U.S. Highway 522, Mount Union, Huntingdon County, PA

  6. View looking northeast of console table and mirror flanked by ...

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

    View looking northeast of console table and mirror flanked by 18th century French chairs in the first floor Reception Hall - Perry Belmont House, 1618 New Hampshire Avenue, NW, Washington, District of Columbia, DC

  7. 3. VIEW OF NORTHEAST CORNER OF THE BUILDING FROM ABOVE, ...

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

    3. VIEW OF NORTHEAST CORNER OF THE BUILDING FROM ABOVE, APPROXIMATELY AT 10TH. FLOOR LEVEL. VIEW OVERLOOKS CORNER OF FRANKLIN AND 15TH STREET. - Pacific Telephone & Telegraph Company Building, 1519 Franklin Street, Oakland, Alameda County, CA

  8. 6. DETAIL VIEW OF NORTHEAST END OF BRIDGE, SHOWING ROCKER ...

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

    6. DETAIL VIEW OF NORTHEAST END OF BRIDGE, SHOWING ROCKER ARM PORTION OF BASCULE - Seddon Island Scherzer Rolling Lift Bridge, Spanning Garrison Channel from Tampa to Sedden Island, Tampa, Hillsborough County, FL

  9. 18. VIEW NORTHEAST, SHAFT, CAM, AND OPERATING ARM FOR NORTH ...

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

    18. VIEW NORTHEAST, SHAFT, CAM, AND OPERATING ARM FOR NORTH END LOCK, INBOARD SIDE OF WEST BASCULE GIRDER - Grand Street Bridge, Spanning Pequonnock River at Grand Street, Bridgeport, Fairfield County, CT

  10. 4. View of center tower at Clover Island, facing northeast. ...

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

    4. View of center tower at Clover Island, facing northeast. Pasco-Kennewick automobile bridge in background, lower right. - Pasco-Kennewick Transmission Line, Columbia River Crossing Towers, Columbia Drive & Gum Street, Kennewick, Benton County, WA

  11. 8. VIEW OF ROOM 101 (ASSEMBLY ROOM) FROM NORTHEAST CORNER ...

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

    8. VIEW OF ROOM 101 (ASSEMBLY ROOM) FROM NORTHEAST CORNER SHOWING FLEXIBLE AIR-CONDITIONING DUCT - Vandenberg Air Force Base, Space Launch Complex 3, Vehicle Support Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  12. General view of Antenna Array and building complex, looking northeast ...

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

    General view of Antenna Array and building complex, looking northeast - Over-the-Horizon Backscatter Radar Network, Tulelake Radar Site Receive Sector Six Antenna Array, Unnamed Road West of Double Head Road, Tulelake, Siskiyou County, CA

  13. 113. COOLING WATER PIPING INTO COMPRESSORS, NORTHEAST CORNER OF MECHANICAL ...

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

    113. COOLING WATER PIPING INTO COMPRESSORS, NORTHEAST CORNER OF MECHANICAL EQUIPMENT ROOM (201), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  14. 1. PIER 4, NORTHEAST CORNER, FROM WEST END OF NORTH ...

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

    1. PIER 4, NORTHEAST CORNER, FROM WEST END OF NORTH MARGINAL WHARF, LOOKING SOUTHEAST ACROSS BERTH AREAS, WITH SIGNAL TOWER AT CENTER. - Oakland Naval Supply Center, Piers 4 & 5, Piers 4 & 5, Oakland, Alameda County, CA

  15. 16. PERSPECTIVE VIEW (NORTHEAST) OF WEST TERREPLEIN OF SOUTHWEST DEMIBASTION ...

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

    16. PERSPECTIVE VIEW (NORTHEAST) OF WEST TERREPLEIN OF SOUTHWEST DEMI-BASTION SHOWING RELATIONSHIP TO MAIN GATE AND OFFICERS' QUARTERS - Fort Washington, Fort, 13551 Fort Washington Road, Fort Washington Forest, Prince George's County, MD

  16. 1. PERSPECTIVE VIEW (NORTHEAST) FROM ESPLANADE OF NORTHWEST DEMIBASTION SHOWING ...

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

    1. PERSPECTIVE VIEW (NORTHEAST) FROM ESPLANADE OF NORTHWEST DEMI-BASTION SHOWING GLACIS AND RELATIONSHIP TO MAIN GATE - Fort Washington, Fort, 13551 Fort Washington Road, Fort Washington Forest, Prince George's County, MD

  17. 90. VIEW NORTHEAST OF BUILDING 98 OIL HOUSE AND STORAGE ...

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

    90. VIEW NORTHEAST OF BUILDING 98 OIL HOUSE AND STORAGE TANK; OIL FOR POWER GENERATION WAS UNLOADED FROM TANK CARS AND STORED AT THIS FACILITY - Scovill Brass Works, 59 Mill Street, Waterbury, New Haven County, CT

  18. 3. Oil House, Southern Pacific Railroad Carlin, northeast elevation, view ...

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

    3. Oil House, Southern Pacific Railroad Carlin, northeast elevation, view to southwest (135mm lens). - Southern Pacific Railroad, Carlin Shops, Oil House, Foot of Sixth Street, Carlin, Elko County, NV

  19. INTERIOR OF MAIN SPACE IN NORTHEAST SHOPS SECTION, VIEW FACING ...

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

    INTERIOR OF MAIN SPACE IN NORTHEAST SHOPS SECTION, VIEW FACING SOUTH-SOUTHEAST. - Naval Air Station Barbers Point, Assembly & Repair Shop, Between Enterprise Avenue & Wright, Midway, & Langley Streets, Ewa, Honolulu County, HI

  20. Partial Northeast Elevation Mill #5 East & #5 West ...

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

    Partial Northeast Elevation - Mill #5 East & #5 West (Part 4), Typical Floor - Partial Plan Mill #5 East & #5 West (Part 4) - Boott Cotton Mills, John Street at Merrimack River, Lowell, Middlesex County, MA

  1. 112. REFRIGERANT CONDENSER TANKS AND PRESSURE CONTROLS IN NORTHEAST CORNER ...

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

    112. REFRIGERANT CONDENSER TANKS AND PRESSURE CONTROLS IN NORTHEAST CORNER OF MECHANICAL EQUIPMENT ROOM (201), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  2. 4. VIEW OF NORTHEAST RAILING TERMINATION; VIEWED FROM THE WEST ...

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

    4. VIEW OF NORTHEAST RAILING TERMINATION; VIEWED FROM THE WEST - La Verkin Creek Bridge, Spanning La Verkin Creek on State Route 17, 0.7 miles northwest of La Verkin , La Verkin, Washington County, UT

  3. View to northeast, showing west elevation and south side. Proximity ...

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

    View to northeast, showing west elevation and south side. Proximity of fence of adjacent subdivision precluded photography of north side. - Drew-Sherwood Farm, Barn, 7927 Elk Grove Boulevard, Elk Grove, Sacramento County, CA

  4. 2. GENERAL VIEW LOOKING NORTHEAST, SHOWING COKE MACHINE (CENTER), INTERMEDIATE ...

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

    2. GENERAL VIEW LOOKING NORTHEAST, SHOWING COKE MACHINE (CENTER), INTERMEDIATE TIPPLE (RIGHT), AND OVENS - Shoaf Mine & Coke Works, East side of Shoaf, off Township Route 472, Shoaf, Fayette County, PA

  5. 92. VIEW OF CHART RECORDERS AND PERSONAL COMPUTER LINING NORTHEAST ...

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

    92. VIEW OF CHART RECORDERS AND PERSONAL COMPUTER LINING NORTHEAST CORNER OF AUTOPILOT ROOM - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  6. VIEW OF PARTIAL FRONT ELEVATION OF MARINE BARRACKS, LOOKING NORTHEAST ...

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

    VIEW OF PARTIAL FRONT ELEVATION OF MARINE BARRACKS, LOOKING NORTHEAST (with scale stick) - Naval Computer & Telecommunications Area Master Station, Eastern Pacific, Radio Transmitter Facility Lualualei, Marine Barracks, Intersection of Tower Drive & Morse Street, Makaha, Honolulu County, HI

  7. VIEW OF PARTIAL FRONT ELEVATION OF MARINE BARRACKS, LOOKING NORTHEAST ...

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

    VIEW OF PARTIAL FRONT ELEVATION OF MARINE BARRACKS, LOOKING NORTHEAST (without scale stick). - Naval Computer & Telecommunications Area Master Station, Eastern Pacific, Radio Transmitter Facility Lualualei, Marine Barracks, Intersection of Tower Drive & Morse Street, Makaha, Honolulu County, HI

  8. TOPOGRAPHIC VIEW OF MAIN STREET LOOKING NORTHEAST, WITH THE FIRST ...

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

    TOPOGRAPHIC VIEW OF MAIN STREET LOOKING NORTHEAST, WITH THE FIRST BANK OF JOSEPH IN THE FOREGROUND, AND THE SCHLUER BUILDING NEAR THE CENTER OF FRAME. - Joseph Main Street, Between Joseph & Second Avenues, Joseph, Wallowa County, OR

  9. View towards the northeast of coffee beans drying on the ...

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

    View towards the northeast of coffee beans drying on the third floor with hopper and drum type dryer in background - Santaella Coffee Processing Site, Highway 139, Kilometer 10.6, Maraguez, Ponce Municipio, PR

  10. 2. General view to northeast along Barton Avenue showing central ...

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

    2. General view to northeast along Barton Avenue showing central courtyard and rotunda of hospital - Portsmouth Naval Hospital, Hospital Building, Rixey Place, bounded by Williamson Drive, Holcomb Road, & The Circle, Portsmouth, Portsmouth, VA

  11. 3. MAIN HOSPITAL, VIEW OF EAST SIDE AND NORTHEAST CORNER. ...

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

    3. MAIN HOSPITAL, VIEW OF EAST SIDE AND NORTHEAST CORNER. - Presidio of San Francisco, Letterman General Hospital, Building No. 27, Letterman Hospital Complex, Edie Road, San Francisco, San Francisco County, CA

  12. 4. View northeast of west (partial) and south elevations. ...

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

    4. View northeast of west (partial) and south elevations. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  13. 29. View of oil storage shed, looking northeast. Photo by ...

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

    29. View of oil storage shed, looking northeast. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  14. 17. General view of dam and headworks, looking northeast. Photo ...

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

    17. General view of dam and headworks, looking northeast. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  15. 2. VIEW OF NORTHWEST SIDE SHOWING NORTHEAST (GABLE END) FRONT. ...

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

    2. VIEW OF NORTHWEST SIDE SHOWING NORTHEAST (GABLE END) FRONT. (BUILDING 114 IS VISIBLE ON RIGHT.) - Fort McPherson, World War II Station Hospital, G. U. Treatment Unit Dispensary, Thorne Avenue, Atlanta, Fulton County, GA

  16. Fireplace detail, east wall, northeast secondfloor room, main block, showing ...

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

    Fireplace detail, east wall, northeast second-floor room, main block, showing ghost of surround and mantle. - Lazaretto Quarantine Station, Wanamaker Avenue and East Second Street, Essington, Delaware County, PA

  17. Detail of northeast stair entry with vaulted stair landing and ...

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

    Detail of northeast stair entry with vaulted stair landing and ghost of former stair arch below stepped rail, facing west. - Marine Barracks, Panama Canal, Barracks Building, 100' North of Thatcher Highway, Balboa, Former Panama Canal Zone, CZ

  18. INTERIOR VIEW LOOKING NORTHEAST, SHOWING FURNACE NO. 1 (ca. 1910. ...

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

    INTERIOR VIEW LOOKING NORTHEAST, SHOWING FURNACE NO. 1 (ca. 1910. Nameplate reads: "Heroult Electric Furnace, Capacity 6 tons, Built by American Bridge Company, Pencoyd, PA, No. 33") - Braeburn Alloy Steel, Braeburn Road at Allegheny River, Lower Burrell, Westmoreland County, PA

  19. AERIAL VIEW, LOOKING NORTHEAST, SHOWING ANIMAS RIVER IN CENTER FOREGROUND, ...

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

    AERIAL VIEW, LOOKING NORTHEAST, SHOWING ANIMAS RIVER IN CENTER FOREGROUND, POWERHOUSE IN LEFT CENTER, AND SHENANDOAH-DIVES (MAYFLOWER) MILL AND TAILINGS PONDS IN DISTANCE. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  20. 10. View to northeast from near siphon structure showing broad, ...

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

    10. View to northeast from near siphon structure showing broad, U-shaped earthen banked ditch - Natomas Ditch System, Blue Ravine Segment, Juncture of Blue Ravine & Green Valley Roads, Folsom, Sacramento County, CA

  1. 3. Oblique view of 213 Division Street, looking northeast, showing ...

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

    3. Oblique view of 213 Division Street, looking northeast, showing rear (west) facade and south side, 215 Division Street is visible at left and Fairbanks Company appears at right - 213 Division Street (House), Rome, Floyd County, GA

  2. 2. Oblique view of 215 Division Street, looking northeast, showing ...

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

    2. Oblique view of 215 Division Street, looking northeast, showing rear (west) facade and south side, 217 Division Street is visible at left and Fairbanks Company appears at right - 215 Division Street (House), Rome, Floyd County, GA

  3. 3. Keeper's house, view northwest, southeast and northeast sides ...

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

    3. Keeper's house, view northwest, southeast and northeast sides - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  4. 4. Light tower and keeper's house, view northeast, southwest side ...

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

    4. Light tower and keeper's house, view northeast, southwest side - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  5. 2. Keeper's house and light tower, view southwest, northeast and ...

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

    2. Keeper's house and light tower, view southwest, northeast and northwest sides - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  6. Straight on view of northeast side of Olive Switching Station ...

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

    Straight on view of northeast side of Olive Switching Station from north side of San Fernando Road facing southwest - Olive Switching Station, 13355 San Fernando Road, Los Angeles, Los Angeles County, CA

  7. 18. UPPER STATION, FIRST FLOOR, OPERATOR'S CABIN, LOOKING NORTH, NORTHEAST. ...

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

    18. UPPER STATION, FIRST FLOOR, OPERATOR'S CABIN, LOOKING NORTH, NORTHEAST. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  8. 14. UPPER STATION, FRONT AND WEST FACADES, LOOKING NORTHEAST. ...

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

    14. UPPER STATION, FRONT AND WEST FACADES, LOOKING NORTHEAST. - Monongahela Incline Plane, Connecting North side of Grandview Avenue at Wyoming Street with West Carson Street near Smithfield Street, Pittsburgh, Allegheny County, PA

  9. FEATURE 2, OPEN SIDE OF SHELTER, VIEW FACING NORTHEAST. ...

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

    FEATURE 2, OPEN SIDE OF SHELTER, VIEW FACING NORTHEAST. - Naval Air Station Barbers Point, Anti-Aircraft Battery Complex-Shelter, East of Coral Sea Road, northwest of Hamilton Road, Ewa, Honolulu County, HI

  10. SOUTHWEST SIDE OF TANK, WITH ENTRY DOOR. Looking northeast ...

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

    SOUTHWEST SIDE OF TANK, WITH ENTRY DOOR. Looking northeast - Edwards Air Force Base, X-15 Engine Test Complex, Tank & Garage, Rogers Dry Lake, east of Runway between North Base & South Base, Boron, Kern County, CA

  11. View looking southwest showing northeast corner, with northwest corner of ...

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

    View looking southwest showing northeast corner, with northwest corner of building no. 1015 (ice house/storage shed) showing at the left. - McGraw Ranch, Eagle's Nest Cabin, McGraw Ranch Road, Estes Park, Larimer County, CO

  12. 1. FRONT CORNER, LOOKING NORTHEAST, TOP HALF OF 'DUTCH DOORS' ...

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

    1. FRONT CORNER, LOOKING NORTHEAST, TOP HALF OF 'DUTCH DOORS' LEANING AGAINST FRONT WALL. - A. D. Wilcox Drift Mine, Boiler Cabin, Linda Creek near Dalton Highway, Bettles, Yukon-Koyukuk Census Area, AK

  13. 4. VIEW SHOWING EXCAVATION IN ARIZONA CANAL, 8 MILES NORTHEAST ...

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

    4. VIEW SHOWING EXCAVATION IN ARIZONA CANAL, 8 MILES NORTHEAST OF PHOENIX. NOTE MEN DRILLING AND EXCAVATING IN OPERATION; CAMELBACK MOUNTAIN IN THE DISTANCE Photographer: Walter J. Lubken. No date - Arizona Canal, North of Salt River, Phoenix, Maricopa County, AZ

  14. PLANT AND PIER #2 EXCAVATION. View is to the northeast, ...

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

    PLANT AND PIER #2 EXCAVATION. View is to the northeast, looking from Humboldt County side of river toward Trinity County side - South Fork Trinity River Bridge, State Highway 299 spanning South Fork Trinity River, Salyer, Trinity County, CA

  15. 15. View northeast of main control panels, Arctic and Tropic ...

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

    15. View northeast of main control panels, Arctic and Tropic Chambers, in machine area. - Natick Research & Development Laboratories, Climatic Chambers Building, U.S. Army Natick Research, Development & Engineering Center (NRDEC), Natick, Middlesex County, MA

  16. 8. Keeper's house, view west, southeast and northeast sides ...

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

    8. Keeper's house, view west, southeast and northeast sides - Goat Island Light Station, Goat Island, next to entrance to Cape Porpoise Harbor, just south of Trott Island, Cape Porpoise, York County, ME

  17. 7. VIEW OF APPROACH TO BRIDGE #2, LOOKING NORTHEAST, WITH ...

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

    7. VIEW OF APPROACH TO BRIDGE #2, LOOKING NORTHEAST, WITH WEST END OF BRIDGE #3 IN BACKGROUND. ROCK OVERHANG IS VISIBLE - Goat Trail Mining Road, Highway 20, 1.5 miles North of Newhalem, Newhalem, Whatcom County, WA

  18. 10. VIEW LOOKING NORTHEAST, COLUMN SUPPORTS, HOPPER CHUTES AND CONCRETE ...

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

    10. VIEW LOOKING NORTHEAST, COLUMN SUPPORTS, HOPPER CHUTES AND CONCRETE SUPPORT LIPS, AND CONVEYOR DRIVE SHAFT ON SUBDECK - West Shore Railroad, Pier 7 Grain Elevator, Hudson River & Pershing Road vicinity, West New York, Hudson County, NJ

  19. 32. DETAIL OF PAYLOAD PRESSURIZATION PANEL LOCATED IN NORTHEAST CORNER ...

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

    32. DETAIL OF PAYLOAD PRESSURIZATION PANEL LOCATED IN NORTHEAST CORNER OF SLC-3W MST STATION 78 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  20. 4. DETAIL VIEW, LOOKING NORTHEAST, SHOWING BEARING BLOCK AND CONCRETE ...

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

    4. DETAIL VIEW, LOOKING NORTHEAST, SHOWING BEARING BLOCK AND CONCRETE FILLED CYLINDRICAL STEEL RING PIER, WEST TRUSS OF MAIN SPAN AT SOUTH END - Little Missouri River Bridge, Spanning Little Missouri River at CR 179, Okolona, Clark County, AR