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Sample records for formacoes geologicas pertencentes

  1. Geologic, geophysical, and in situ stress investigations in the vicinity of the Dining Car Chimney, Dining Car/Hybla gold tunnels, Nevada Test Site, with sections on geologica investigations, geophysical investigations, and in situ stress investigations

    USGS Publications Warehouse

    Townsend, D.R.; Baldwin, M.J.; Carroll, R.D.; Ellis, W.L.; Magner, J.E.

    1982-01-01

    The Hybla Gold experiment was conducted in the U12e.20 drifts of the E-tunnel complex beneath the surface of Rainier Mesa at the Nevada Test Site. Though the proximity of the Hybla Gold working point to the chimney of the Dining Car event was important to the experiment, the observable geologic effects from Dining Car on the Hybla Gold site were minor. Overburden above the working point is approximately 385 m (1,263 ft). The pre-Tertiary surface, probably quartzite, lies approximately 254 m (833 ft) below the working point. The drifts are mined in zeolitized ash-fall tuffs of tunnel bed 4, subunits K and J, all of Miocene age. The working point is in subunit 4J. Geologic structure in the region around the working point is not complex. The U12e.20 main drift follows the axis of a shallow depositional syncline. A northeast-dipping fault with displacement of approximately 3 m (10 ft) passes within 15.2 m (50 ft) of the Hybla Gold working point. Three faults of smaller displacement pass within 183-290 m (600-950 ft) of the working point, and are antithetic to the 3-m (10-ft) fault. Three exploratory holes were drilled to investigate the chimney of the nearby Dining Car event. Four horizontal holes were drilled during the construction of the U12e.20 drifts to investigate the geology of the Hybla Gold working point.

  2. Daniel A. Valencio 1928”1987

    NASA Astrophysics Data System (ADS)

    Schneider, Otto

    Daniel A. Valencio, Professor of Geophysics at Buenos Aires University, died on May 28, 1987, shortly before his 59th birthday. A pioneer of paleomagnetism and tectonophysics in Latin America, Valencio was an outstanding teacher and investigator in these disciplines.His original employment as an exploration geophysicist in Argentina and Cuba led him to become interested in solid Earth sciences in general in the 1960s. At that time, he laid the foundations of the Laboratory of Paleomagnetism at the Departamento de Ciencias Geologicas of Buenos Aires University. This facility has become a very active center of research and teaching, with emphasis on an interdisciplinary approach that includes the participation of an important group of pupils.

  3. Reconstruction of multistage massive rock slope failure: Polymethodical approach in Lake Oeschinen (CH)

    NASA Astrophysics Data System (ADS)

    Knapp, Sibylle; Gilli, Adrian; Anselmetti, Flavio S.; Hajdas, Irka

    2016-04-01

    Lateglacial and Holocene rock-slope failures occur often as multistage failures where paraglacial adjustment and stress adaptation are hypothesised to control stages of detachment. However, we have only limited datasets to reconstruct detailed stages of large multistage rock-slope failures, and still aim at improving our models in terms of geohazard assessment. Here we use lake sediments, well-established for paleoclimate and paleoseismological reconstruction, with a focus on the reconstruction of rock-slope failures. We present a unique inventory from Lake Oeschinen (Bernese Alps, Switzerland) covering about 2.4 kyrs of rock-slope failure history. The lake sediments have been analysed using sediment-core analysis, radiocarbon dating and seismic-to-core and core-to-core correlations, and these were linked to historical and meteorological records. The results imply that the lake is significantly younger than the ~9 kyrs old Kandersteg rock avalanche (Tinner et al., 2005) and shows multiple rock-slope failures, two of which could be C14-dated. Several events detached from the same area potentially initiated by prehistoric earthquakes (Monecke et al., 2006) and later from stress relaxation processes. The data imply unexpected short recurrence rates that can be related to certain detachment scarps and also help to understand the generation of a historical lake-outburst flood. Here we show how polymethodical analysis of lake sediments can help to decipher massive multistage rock-slope failure. References Monecke, K., Anselmetti, F.S., Becker, A., Schnellmann, M., Sturm, M., Giardini, D., 2006. Earthquake-induced deformation structures in lake deposits: A Late Pleistocene to Holocene paleoseismic record for Central Switzerland. Eclogae Geologicae Helvetiae, 99(3), 343-362. Tinner, W., Kaltenrieder, P., Soom, M., Zwahlen, P., Schmidhalter, M., Boschetti, A., Schlüchter, C., 2005. Der nacheiszeitliche Bergsturz im Kandertal (Schweiz): Alter und Auswirkungen auf die

  4. Historical hydrology and database on flood events (Apulia, southern Italy)

    NASA Astrophysics Data System (ADS)

    Lonigro, Teresa; Basso, Alessia; Gentile, Francesco; Polemio, Maurizio

    2014-05-01

    . More details on previous results of this research activity were recently published (Polemio, 2010; Basso et al., 2012; Lonigro et al., 2013) References Basso A., Lonigro T. and Polemio M. (2012) "The improvement of historical database on damaging hydrogeological events in the case of Apulia (Southern Italy)". Rendiconti online della Società Geologica Italiana, 21: 379-380; Lonigro T., Basso A. and Polemio M. (2013) "Historical database on damaging hydrogeological events in Apulia region (Southern Italy)". Rendiconti online della Società Geologica Italiana, 24: 196-198; Polemio M. (2010) "Historical floods and a recent extreme rainfall event in the Murgia karstic environment (Southern Italy)". Zeitschrift für Geomorphologie, 54(2): 195-219.

  5. Deductive Coordination of Multiple Geospatial Knowledge Sources

    NASA Astrophysics Data System (ADS)

    Waldinger, R.; Reddy, M.; Culy, C.; Hobbs, J.; Jarvis, P.; Dungan, J. L.

    2002-12-01

    Deductive inference is applied to choreograph the cooperation of multiple knowledge sources to respond to geospatial queries. When no one source can provide an answer, the response may be deduced from pieces of the answer provided by many sources. Examples of sources include (1) The Alexandria Digital Library Gazetteer, a repository that gives the locations for almost six million place names, (2) The Cia World Factbook, an online almanac with basic information about more than 200 countries. (3) The SRI TerraVision 3D Terrain Visualization System, which displays a flight-simulator-like interactive display of geographic data held in a database, (4) The NASA GDACC WebGIS client for searching satellite and other geographic data available through OpenGIS Consortium (OGC) Web Map Servers, and (5) The Northern Arizona University Latitude/Longitude Distance Calculator. Queries are phrased in English and are translated into logical theorems by the Gemini Natural Language Parser. The theorems are proved by SNARK, a first-order-logic theorem prover, in the context of an axiomatic geospatial theory. The theory embodies a representational scheme that takes into account the fact that the same place may have many names, and the same name may refer to many places. SNARK has built-in procedures (RCC8 and the Allen calculus, respectively) for reasoning about spatial and temporal concepts. External knowledge sources may be consulted by SNARK as the proof is in progress, so that most knowledge need not be stored axiomatically. The Open Agent Architecture (OAA) facilitates communication between sources that may be implemented on different machines in different computer languages. An answer to the query, in the form of text or an image, is extracted from the proof. Currently, three-dimensional images are displayed by TerraVision but other displays are possible. The combined system is called Geo-Logica. Some example queries that can be handled by Geo-Logica include: (1) show the

  6. Paleoseismic observations of an onshore transform boundary: The Magallanes-Fagnano fault, Tierra del Fuego, Argentina

    USGS Publications Warehouse

    Costa, C.H.; Smalley, R., Jr.; Schwartz, D.P.; Stenner, H.D.; Ellis, M.; Ahumada, E.A.; Velasco, M.S.

    2006-01-01

    We present preliminary information on the geomorphologic features and paleoseismic record associated with the ruptures of two Ms 7.8 earthquakes that struck Tierra del Fuego and the southernmost continental margin of South America on December 17, 1949. The fault scarp was surveyed in several places cast of Lago Fagnano and a trench across a secondary fault trace of the Magallanes-Fagnano fault was excavated at the Ri??o San Pablo. The observed deformation in a 9 kyr-old peat bog sequence suggests evidence for two, and possibly three pre-1949 paleoearthquakes is preserved in the stratigraphy. The scarp reaches heights up to 11 m in late Pleistocene-Holocence(?) deposits, but the vertical component of the 1949 events was always less than ???1 m. This observation also argues for the occurrence of previous events during the Quaternary. Along die part of the fault we investigated east of Lago Fagnano, the horizontal component of the 1949 rupture does not exceed 4 m and is likely lower than 0.4 m, which is consistent with the kinematics of a local releasing bend, or at the end of a strike-slip rupture zone. ?? 2006 Revista de la Asociacio??n Geolo??gica Argentina.

  7. Lithostratigraphy and depositional history of the Late Cenozoic hominid-bearing successions in the Yuanmou Basin, southwest China

    NASA Astrophysics Data System (ADS)

    Urabe, Atsushi; Nakaya, Hideo; Muto, Tetsuji; Katoh, Shigehiro; Hyodo, Masayuki; Shunrong, Xue

    2001-09-01

    Late Cenozoic strata bearing hominids and hominoids are distributed in the Yuanmou Basin, Yunnan, southwest China. Incisors of Homo erectus discovered in these strata in 1965 reportedly show primitive features known in Africa (Hu, Acta geologica sinica 1 (1973, p. 65). However, recent paleomagnetic study has revealed that the age of the hominid correlates to the early Brunhes chron (Hyodo et al., Journal of human evolution (2001), submitted). The lithostratigraphy of the successions that yield many mammalian fossils including those of the hominid, and the record of Equus is re-examined. The successions are divided in ascending order into the Longchuan, Shagou, Gantang (newly proposed Yangliuchun and Daipojing Members) and Yuanmou (newly proposed Dainawu and Niujianbao Members) Formations, based on different lithology and sedimentary facies. The newly proposed depositional systems of the formations are in ascending order, alluvial fan, ephemeral braided river, sandy braided river, ephemeral gravelly braided river and alluvial fan systems. The change in facies and paleocurrents revealed in the successions suggest that the basin was initiated as a syncline basin at ca 3.5 Ma and was completed as an asymmetric half graben by active movement of the eastern marginal fault in the early Middle Pleistocene.

  8. A revised inoceramid biozonation for the Upper Cretaceous based on high-resolution carbon isotope stratigraphy in northwestern Hokkaido, Japan

    NASA Astrophysics Data System (ADS)

    Hayakawa, Tatsuya; Hirano, Hiromichi

    2013-06-01

    Hayakawa, T., Hirano, H. 2013. A revised inoceramid biozonation for the Upper Cretaceous based on high-resolution carbon isotope stratigraphy in northwestern Hokkaido, Japan. Acta Geologica Polonica, 63 (2), 239-263. Warszawa. Biostratigraphic correlations of inoceramid bivalves between the North Pacific and Euramerican provinces have been difficult because the inoceramid biostratigraphy of the Japanese strata has been based on endemic species of the northwest Pacific. In this study, carbon stable isotope fluctuations of terrestrial organic matter are assembled for the Upper Cretaceous Yezo Group in the Haboro and Obira areas, Hokkaido, Japan, in order to revise the chronology of the inoceramid biozonation in Japan. The carbon isotope curves are correlated with those of marine carbonates in English and German sections with the aid of age-diagnostic taxa. According to the correlations of the carbon isotope curves, 11 isotope events are recognised in the sections studied. As a result of these correlations, the chronology of the inoceramid biozones of the Northwest Pacific has been considerably revised. The revised inoceramid biozones suggest that the timing of the origination and extinction of the inoceramids in the North Pacific biotic province is different from the stage/substage boundaries defined by inoceramids, as used in Europe and North America.

  9. Impacts of heavy groundwater pumping on hydrogeological conditions in Libya: Past and present development and future prognosis on a regional scale

    NASA Astrophysics Data System (ADS)

    Elgzeli, Yousef M.; Ondovčin, Tomáš; Hrkal, Zbyněk; Krásný, Jiří; Mls, Jiří

    2013-06-01

    Elgzeli, Y.M., Ondovčin, T., Hrkal, Z., Krasny, J. and Mls, J. 2011. Impacts of heavy groundwater pumping on hydrogeological conditions in Libya: Past and present development and future prognosis on a regional scale. Acta Geologica Polonica, 63 (2), 283-296. Warszawa. Libya, like many other regions with arid climates, suffers from inadequate water resources to cover all the needs of this rapidly developing country. Increasing amounts of water are needed to supply the population, as well as for agricultural irrigation and industrial use. As groundwater is the main water source in the country, it represents a natural resource of the highest economic and social importance. Conceptual and numerical models were implemented on a regional scale to show how the natural situation has changed following heavy groundwater abstraction during the last decades in the northwestern part of the country. The results of the numerical model indicated that the current zones of depression of the piezometric surface could have been caused by smaller withdrawn amounts than previously estimated. The differences in the assessed withdrawn groundwater volumes seem to be quite high and might have a considerable influence on the future possibilities of groundwater use in the study region.

  10. On variation in Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian of western Kazakhstan

    NASA Astrophysics Data System (ADS)

    Kennedy, William James

    2013-12-01

    Kennedy, W.J. 2013. On variation in Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian of western Kazakhstan Acta Geologica Polonica, 63(4), 443-468. Warszawa. An assemblage of 94 specimens of Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian Sharpeiceras schlueteri Subzone of the Mantelliceras mantelli Zone of the Besakty section in the Mangyshlak Mountains of western Kazakhstan includes 26 complete adults that range from to 59-174 mm in diameter. No size-related dimorphism was detected in the assemblage, which shows wide, continuous intraspecific variation. This is described in terms of five formae; from robust to gracile these are: ventriosa, varians sensu stricto, subtuberculata , intermedia, and subplana. The ratio of robust (ventriosa + varians sensu stricto) to gracile (subtuberculata + intermedia + subplana) individuals is 34% to 66%. The reference specimens of the formae and their synonyms are described and illustrated, and related to the Besakty material. The modification of adult body chamber ornament of all formae is documented, and Jakeiceras Cooper and Owen, 2011 is shown to be based on an adult of a passage form between forma subtuberculata and forma intermedia. The differences between Lower Cenomanian S. varians, lower Middle Cenomanian S. coupei (Brongniart, 1822), and upper Middle and lower Upper Cenomanian S. lymensis Spath, 1926b are described and illustrated.

  11. V Olimpíada Brasileira de Astronomia

    NASA Astrophysics Data System (ADS)

    Villas da Rocha, J. F.; Canalle, J. B. G.; Wuesnche, C. A.; de Medeiros, J. R., Silva, A. V. R.; Lavouras, D. F.; Dottori, H. A.; Maia, M. A. G.; Vieira Martins, R.; Poppe, P. C. R.

    2003-08-01

    Neste trabalho apresentamos os resultados da V Olimpíada Brasileira de Astronomia, a qual ocorreu em 11/05/2002 em todos os estabelecimentos de ensino fundamental ou médio previamente cadastrados. Participaram do evento 60.338 alunos distribuídos por 1469 escolas pertencentes a todos os Estados brasileiros. Uma equipe de 5 alunos foi escolhida para representar o Brasil na VII Olimpíada Internacional de Astronomia que ocorreu na Rússia em 2002 e dois de nossos alunos ganharam a medalha de bronze naquele evento.

  12. Lithological and structural controls for glacial valley development in the Valais, Swiss Alps

    NASA Astrophysics Data System (ADS)

    Valla, P. G.; Herman, F.; Champagnac, J.-D.

    2009-04-01

    variations. These results clearly indicate that glacial erosion can be highly modulated by structural and lithological conditions. References : - Anderson, R. S., Molnar, P. and Kessler, M. A. (2006). Features of glacial valley profiles simply explained. Journal of Geophysical Research Earth Surface, 111 (1), F01004. - Champagnac, J.-D., Sue, C., Delacou, B. and Burkhard, M. (2003). Brittle orogen-parallel extension in the internal zones of the Swiss Alps (South Valais). Ecologae Geologicae Helvetiae, 96 (3), pp. 325-338. - Harbor, J. M. (1995). Development of glacial-valley cross sections under conditions of spatially variable resistance to erosion. Geomorphology, 14 (2), pp. 99-10. - Herman, F. and Braun, J. (2008). Evolution of the glacial landscape of the Southern Alps of New Zealand: Insights from a glacial erosion model. Journal of Geophysical Research Earth Surface, 113 (2), F02009. - Hubbard, M., Mancktelow, N.S. (1992). Lateral displacement during Neogene convergence in the western and central Alps. Geology, 20 (10), pp. 943-946. - Hinderer, M. (2001). Late quaternary denudation of the Alps, Valley and lake fillings and modern river loads. Geodinamica Acta, 14 (4), pp. 231-263. - Kelly, M. A., Buoncristiani, J.-F. and Schlüchter, C. (2004). A reconstruction of the last glacial maximum (LGM) ice-surface geometry in the western Swiss Alps and contiguous Alpine regions in Italy and France. Eclogae Geologicae Helvetiae, 97(1), pp. 57-75. - MacGregor, K. R., Anderson, R. S., Anderson, S. P. and Waddington, E. D. (2000). Numerical simulations of glacial-valley longitudinal profile evolution. Geology, 28(11), pp. 1031-1034.

  13. Assessing the Record of Anoxic/Dysoxic Events in Lower Aptian Cupido/La Peña Formations, Northeastern Mexico

    NASA Astrophysics Data System (ADS)

    Maurrasse, F. J.; Barragan-Manzo, R.; Ponton, C.

    2008-05-01

    -thick each that are remarkably devoid of benthic foraminifers. They occur at 5. 72 m, 11.45m and 29.6 m, respectively, below the La Peña Fm. Variations within the Cupido Fm are consistent with fluctuating high- productivity, well-oxygenated neritic environment punctuated by development of hypoxic to anoxic bottom waters (Maurrasse et al., 2006). These recurrent episodes of severe oxygen depletion fall within the time interval that may be correlational with the infrajacent D. deshayesi to possibly the D. wessi zones in the Mediterranean ammonite biozonation scheme. We interpret these horizons to represent recurrent hypoxic to anoxic bottom conditions that are local expression of global forcing factors during Cretaceous greenhouse conditions that lead to well-defined OAE-1a and the subsequent anoxic events. Barragan-Manzo, R., and Maurrasse, F., (2008) Revista Mexicana de Ciencias Geologicas, v. 25, 1, p. 145-157. Barragan-Manzo, R., and Mendez-Franco, 2005, Towards a standard ammonite zonation for the Aptian (Lower Cretaceous) of northern Mexico. Revista Mexicana de Ciencias Geologicas, v. 22, 1, p. 39-47. Maurrasse, F. J-M. R., Barragan-Manzo, R., and Ponton, C. 2006, Cupido- La Peña Formations: High-Productivity to Super-Productivity during the Cretaceous Enhanced Greenhouse Conditions, GSA Abst.with programs v. 38, no 7, p. 491.

  14. Ordovidan K-bentonites in the Precordillera of San Juan and its tectomasmatic significance

    USGS Publications Warehouse

    Cingolani, C.A.; Huff, W.; Bergstrom, S.; Kolata, D.

    1997-01-01

    A succession of approximately 35 early Middle Ordovician K-bentonite beds are exposed in the Precordillera region near the town of Jachal, in San Juan Province (at Cerro Viejo and La Chilca sections). They occur in argillaceous limestone in the upper part of the San Juan Limestone and in the interbedded shales and mudstones at the base of the overlying Los Azules Formation. Total thickness of the K-bentonite-bearing interval is 23 m and individual beds range from 1 to 65 cm thick. An essentially Arenig-Llanvirn age for the K-bentonite succession is indicated by the presence of graptolites diagnostic of the Paraglossograptus tentaculatus Zone and conodonts indicating the Eoplacognathus suecicus Zone. The bentonites consist mainly of Rl ordered illite/smectite, characteristic of most of the lower Paleozoic K-bentonites, plus volcanogenic crystals. Similar to other K-bentonites, these probably represent the distal, glass-rich portion of fall-out ash beds derived from collision zone explosive volcanism. The geochemical data and preliminary plots on the magmatic discrimination diagram indicate the parental magma was of rhyolite to trachyandesite composition. Tectonic discrimination diagrams show the setting of Cerro Viejo ash layers as falling on the boundary between volcanic arc and within plate rocks, typical of collision margin felsic volcanic rocks. U-Pb isotope dating for two zircon fractions from one sample show a lower concordia intercept of 461, +7-10 Ma coincident with the biostratigraphic age. Thus, they have important implications for the origin and early history of the allochtonous Precordillera terrane and the Pacific margin of South America. Furthermore, they are potentially important in interpretations of the paleogeographic relations of Laurentia and Gondwana during Ordovician time. ?? 1997 Asociacio??n Geolo??gica Argentina.

  15. Tectonic stress inversion of large multi-phase fracture data sets: application of Win-Tensor to reveal the brittle tectonic history of the Lufilan Arc, DRC

    NASA Astrophysics Data System (ADS)

    Delvaux, Damien; Kipata, Louis; Sintubin, Manuel

    2013-04-01

    Large fault-slip data sets from multiphase orogenic regions present a particular challenge in paleostress reconstructions. The Lufilian Arc is an arcuate fold-and-thrust belt that formed during the late Pan-African times as the result of combined N-S and E-W amalgamation of Gondwana in SE-DRCongo and N-Zambia. We studied more than 22 sites in the Lufilian Arc, and its foreland and correlated the results obtained with existing result in the Ubende belt of W-Tanzania. Most studied sites are characterized by multiphase brittle deformation in which the observed brittle structures are the result of progressive saturation of the host rock by neoformed fractures and the reactivation of early formed fractures. They correspond to large mining exploitations with multiple large and continuous outcrops that allow obtaining datasets sufficiently large to be of statistical significance and often corresponding to several successive brittle events. In this context, the reconstruction of tectonic stress necessitates an initial field-base separation of data, completed by a dynamic separation of the original data set into subsets. In the largest sites, several parts of the deposits have been measured independently and are considered as sub-sites that are be processed separately in an initial stage. The procedure used for interactive fault-slip data separation and stress inversion will be illustrated by field examples (Luiswishi and Manono mining sites). This principle has been applied to all result in the reconstruction of the brittle tectonic history of the region, starting with two major phases of orogenic compression, followed by late orogenic extension and extensional collapse. A regional tectonic inversion during the early Mesozoic, as a result of far- field stresses mark the transition towards rift-related extension. More details in Kipata, Delvaux et al.(2013), Geologica Belgica 16/1-2: 001-017 Win-Tensor can be downloaded at: http://users.skynet.be/damien.delvaux/Tensor/tensor-index.html

  16. Mineralogical and petrological investigations of rocks cored from depths higher than 440m during the CFDDP drilling activities at the Campi Flegrei caldera (southern Italy).

    NASA Astrophysics Data System (ADS)

    Mormone, Angela; Piochi, Monica; Balassone, Giuseppina; Carlino, Stefano; Somma, Renato; Troise, Claudia; De Natale, Giuseppe

    2014-05-01

    The Campi Flegrei caldera is one of the highest-risk volcanic areas on the Earth and the drilling exploiting activities carried by the Azienda Geologica Italiana Petroli (AGIP) and the Società Anonima Forze Endogene Napoletane (SAFEN) since the '40 have produced the main constrains to the definition of the subsurface structure of the caldera. The eastern part of the caldera represents among the least known in the area in terms of both volcanic and geothermal evolution. Recently, in the 2012, the Campi Flegrei Deep Drilling Project (CFDDP) allowed performing a 506m hole in this sector of the caldera, i.e. in the Bagnoli Plain, where the western districts of the Neapolitan city developed. Here, we present the preliminary results from mineralogical, geochemical and petrological investigations of drilling core samples collected at -443 m and -506 m of depths. Scanning electron microscopy (SEM), microanalysis by energy dispersive spectroscopy (EDS) together with investigations by back-scattered electron mode (SEM-BSE), and powder X-Ray diffraction (XRD) allowed: 1) defining the primary sample lithology; 2) examining the features of both primary and secondary minerals; 3) describing the relationships among texture and secondary mineralization. Sr isotope analyses were furthermore performed on separated feldspars. Density measurements were also carried out on the bottom core. The investigated samples are representative of strongly altered, massive pyroclastic tuffs, which made of a chaotic ashy to sandy matrix including low crystalline juvenile scoria and pumice fragments. Textural features of secondary mineralization are consistent with circulation of hydrothermal fluids as the results of a wide geothermal resource in the caldera. Comparing the paleo-temperature inferred by authigenic minerals occurrence and the temperature measured at the bottom hole (~60°C) during geophysical logs, we suggest the cooling of the hydrothermal system in the eastern sector of the caldera.

  17. Silicified sea life - Macrofauna and palaeoecology of the Neuburg Kieselerde Member (Cenomanian to Lower Turonian Wellheim Formation, Bavaria, southern Germany)

    NASA Astrophysics Data System (ADS)

    Schneider, Simon; Jager, Manfred; Kroh, Andreas; Mitterer, Agnes; Niebuhr, Birgit; Vodrazka, Radek; Wilmsen, Markus; Wood, Christopher J.; Zagorsk, Kamil

    2013-12-01

    Schneider, S., Jager, M., Kroh, A., Mitterer, A., Niebuhr, B., Vodražka, R., Wilmsen, M., Wood, C.J. and Zagoršek, K. 2013. Silicified sea life - Macrofauna and palaeoecology of the Neuburg Kieselerde Member (Cenomanian to Lower Turonian Wellheim Formation, Bavaria, southern Germany). Acta Geologica Polonica, 63(4), 555-610. Warszawa. With approximately 100 species, the invertebrate macrofauna of the Neuburg Kieselerde Member of the Wellheim Formation (Bavaria, southern Germany) is probably the most diverse fossil assemblage of the Danubian Cretaceous Group. Occurring as erosional relicts in post-depositional karst depressions, both the Cretaceous sediments and fossils have been silicified during diagenesis. The Neuburg Kieselerde Member, safely dated as Early Cenomanian to Early Turonian based on inoceramid bivalve biostratigraphy and sequence stratigraphy, preserves a predominantly soft-bottom community, which, however, is biased due to near-complete early diagenetic loss of aragonitic shells. The community is dominated by epifaunal and semi-infaunal bivalves as well as sponges that settled on various (bio-) clasts, and may widely be split into an early bivalve-echinoid assemblage and a succeeding sponge-brachiopod assemblage. In addition to these groups we document ichnofauna, polychaete tubes, nautilids and bryozoans. The fauna provides evidence of a shallow to moderately deep, calm, fully marine environment, which is interpreted as a largescale embayment herein. The fauna of the Neuburg Kieselerde Member is regarded as an important archive of lower Upper Cretaceous sea-life in the surroundings of the Mid-European Island.

  18. Evidence of the latest Ordovician sea level drop on Avalonia in the Condroz Inlier, Belgium, and dating with chitinozoans by comparison with the Ashgill type area, Cautley District, U.K.

    NASA Astrophysics Data System (ADS)

    Vanmeirhaeghe, J.; Vandenbroucke, T.; Verniers, J.

    2003-04-01

    . Geologica Belgica, 5 (in press). VANMEIRHAEGHE, J. &VERNIERS, J. (submitted). Chitinozoans of the Fosses and Génicot Formations (western Condroz Inlier) and further proofs of the Hirnantian glaciation in Belgium. Review of Palaeobotany and Palynology.

  19. Graphical representations of the chemistry of garnets in a three-dimensional MATLAB based provenance plot

    NASA Astrophysics Data System (ADS)

    Knierzinger, Wolfgang; Palzer, Markus; Wagreich, Michael; Meszar, Maria; Gier, Susanne

    2016-04-01

    A newly developed, MATLAB based garnet provenance plot allows a three-dimensional tetrahedral representation of the chemistry of garnets for the endmembers almandine, pyrope, spessartine and grossular. Based on a freely accessible database of Suggate & Hall (2013) and additional EPMA-data on the internet, the chemistry of more than 2500 garnets was evaluated and used to create various subfields that correspond to different facies conditions of metapelitic, metasomatic and metaigneous rocks as well as granitic rocks. These triangulated subfields act as reference structures within the tetrahedron, facilitating assignments of garnet chemistries to different lithologies. In comparison with conventional tenary garnet discrimination diagrams by Mange & Morton (2007), Wright/Preston et al. (1938/2002) and Aubrecht et al. (2009), this tetrahedral provenance plot enables a better assessment of the conditions of formation of garnets by reducing the overlapping of certain subfields. In particular, a clearer distinction between greenschist facies rocks, amphibolite facies rocks and granitic rocks can be achieved. First applications of the tetrahedral garnet plot provided new insights on sedimentary processes during the Lower Miocene in the pre-Alpine Molasse basin. Bibliography Aubrecht, R., Meres, S., Sykora, M., Mikus, T. (2009). Provenance of the detrital garnets and spinels from the Albian sediments of the Czorsztyn Unit (Pieniny Klippen Belt , Western Carpathians, Slovakia). In: Geologica Carpathica, Dec. 2009, 60, 6, pp. 463-483. Mange, M.A., Morton, A.C. (2007). Geochemistry of Heavy Minerals. In: Mange, M.A. & Wright, D.T.(2007).Heavy Minerals in Use, Amsterdam, pp. 345-391. Preston, J., Hartley, A., Mange-Rajetzky, M., Hole, M., May, G., Buck, S., Vaughan, L. (2002). The provenance of Triassic continental sandstones from the Beryl Field, northern North Sea: Mineralogical, geochemical and sedimentological constraints. In: Journal of Sedimentary Research, 72, pp. 18

  20. The ESI scale, an ethical approach to the evaluation of seismic hazards

    NASA Astrophysics Data System (ADS)

    Porfido, Sabina; Nappi, Rosa; De Lucia, Maddalena; Gaudiosi, Germana; Alessio, Giuliana; Guerrieri, Luca

    2015-04-01

    studies have been reviewed: the destructive 1976 February 4 Guatemala, earthquake (M 7.5) and the 1743 February 20 Nardò, historical earthquake (Salento, Southern Italy). The re-analysis of both earthquakes contributes to define more realistic seismic scenarios in terms of intensities assessment and consequent regional seismic hazards. References Michetti A.M., Esposito E., Guerrieri L., Porfido S., Serva L., Tatevossian R., Vittori E., Audemard F., Azuma T., Clague J., Comerci V., Gurpinar A., Mccalpin J., Mohammadioun B., Mörner N.A, Ota Y. And E. Roghozin - 2007. Intensity Scale ESI 2007, Mem. Descrittive della Carta Geologica d'Italia, Roma, 74, 53 pp

  1. Middle Miocene coralline algal facies from the NW Transylvanian Basin (Romania)

    NASA Astrophysics Data System (ADS)

    Chelaru, Ramona; Bucur, Ioan I.; Sǎsǎran, Emanoil; Bǎlc, Ramona; Tǎmas, Tudor

    2016-04-01

    s\\varan E., Bucur I.I., Bǎlc R., Tǎmas T. & Beldean C. (2011). Carbonate facies with rhodoliths from Vǎlenii Șomcutei (NW Transylvanian Basin). In: Bucur I.I. & Sǎs\\varan E. (eds) - 10th International Symposium on Fossil Algae, Cluj-Napoca, Abstract Book, p. 16. [2] Szakács A., Pécskay Z., Silye L., Balogh K., Vlad D. & Fülöp A. (2012). On the age of the Def Tuff, Transylvanian Basin (Romania). Geologica Carpathica, vol. 63(2), p. 139-148.

  2. 40Ar/39Ar dating of the Honghuaqiao Formation in SE China

    NASA Astrophysics Data System (ADS)

    Chang, S.; Zhang, H.; Hemming, S. R.; Mesko, G. T.; Fang, Y.

    2010-12-01

    The Jehol Biota, defined as the characteristic Eosestheria-Ephemeropsis-Lycoptera assemblage (Grabau, 1923, Bulletin of the Geological Survey of China), is widely distributed in eastern and central Asia (Li et al., 1982, Acta Geologica Sinica; Chen, 1988, Acta Palaeontologica Sinica). Abundant and varied fossils of the terrestrial Jehol Biota, including plants, insects, dinosaurs, birds, mammals, and freshwater invertebrates, have been discovered from the Dabeigou, the Yixian and the Jiufotang Formations (or their correlative strata) in northeast China from the Liaoning and Hebei Provinces and Inner Mongolia (Chen and Jin, 1999, Acta Palaeontologica Sinica). In addition, strata that may be correlative with the classic Jehol fossil-bearing formations have been identified extensively in central and eastern China, the Korean Peninsula, Mongolia, and Siberia. In the past three decades mollusk, conchostracan, ostracod, insect, fish, and plant fossils from localities in southeastern China, interpreted as related to the Jehol biota of the northeast, have been found (Mateer and Chen, 1986, Cretaceous Research; Li, 2003, Chinese Science Bulletin; Chen, Li and Batten, 2007, Geological Journal). However, a detailed correlation between the classic Jehol outcrops and the more recently found localities to the South and West has yet to emerge. Volcanic rocks from the Honghuaqiao fossil-bearing Formation in Tuzhou City of eastern Anhui Province, southeastern China provide an excellent opportunity to rectify this situation. Preliminary results of a pilot study suggest that the Honghuaqiao Formation is equivalent to the Longwanshan Formation of Anhui Province, southeastern China and the Yixian Formation, northeastern China (Chang et al., 2009, AGU abstract). Initial 40Ar/39Ar results indicate that conchostracans from the upper Honghuaqiao Formation are approximately 130 Ma. Our ongoing work aims to establish a high-resolution chronostratigraphy for Tuzhou City in Anhui Province

  3. Radioactive source materials in Los Estados Unidos de Venezuela

    USGS Publications Warehouse

    Wyant, Donald G.; Sharp, William N.; Rodriguez, Carlos Ponte

    1953-01-01

    high-grade hydrothermal pitchblende deposits; and highly possible for small, medium- to high-grade despots of carnotite-or copper-uranium bearing sandstone. Recommendations for the Venezuelan uranium program include 1) the systematic collection of a mass general radiometric data by examining sample collections, expanding the gamma-ray program, encouraging the use of Geiger counter by field geologists, and by enlisting the aid of the general public; 2) , the examination of specific areas or localities, chosen on the basis of geologic favorability from the results of the amassing of data, or obtained by hints and rumors; 3), the organization of a unit within the Direccion Tecnica de Geologica to direct, collection, and collate metric data. It is emphasized that to be most fruitful the program requires the application of sounds and imaginative geologic theory.

  4. Minerals and clay minerals assemblages in organic-rich facies: the case study of the Sinemurian-Pliensbachian carbonate deposits of the western Lusitanian Basin (Portugal)

    NASA Astrophysics Data System (ADS)

    Caniço, Ana; Duarte, Luís V.; Silva, Ricardo L.; Rocha, Fernando; Graciano Mendonça Filho, João

    2015-04-01

    phase, and marks the disappearance of the organic-rich facies and increase of carbonate sedimentation. This enrichment was likely favored by the development of more humid conditions at the Sinemurian-Pliensbachian transition. References Duarte, L.V., Silva, R.L., Oliveira, L.C.V., Comas-Rengifo, M.J., Silva, F. 2010. Organic-rich facies in the Sinemurian and Pliensbachian of the Lusitanian Basin, Portugal: Total Organic Carbon distribution and relation to transgressive-regressive facies cycles. Geologica Acta 8, 325-340.

  5. Short-term climate changes in the Holsteinian Interglacial - EGU2012-132

    NASA Astrophysics Data System (ADS)

    Nitychoruk, J.; Bińka, K.; Ruppert, H.; Tudryn, A.

    2012-04-01

    .C., Pross, J., Brauer, A., Kotthoff, U., Lotter, A.F. 2010. Vegetation dynamics and climate variability during the Holsteinian interglacial based on a pollen record from Dethlingen (northern Germany). Quaternary Science Reviews, 29, 3298-3307. Nitychoruk, J. 2000. Climate reconstruction from stable-isotope composition of the Mazovian Interglacial (Holsteinian) lake sediments in eastern Poland. Acta Geologica Polonica, 50, 247-294. Nitychoruk, J., Bińka, K., Hoefs, J., Ruppert, H. & Schneider, J. 2005. Climate reconstruction for the Holsteinian Interglacial in Eastern Poland and its comparison with isotopic data from Marine Isotope Stage 11. Quaternary Science Reviews, 24, 631-644.

  6. Present activity and seismogenic potential of a low-angle normal fault system (Città di Castello, Italy): Constraints from surface geology, seismic reflection data and seismicity

    NASA Astrophysics Data System (ADS)

    Brozzetti, Francesco; Boncio, Paolo; Lavecchia, Giusy; Pace, Bruno

    2009-01-01

    We present new constraints on an active low-angle normal fault system in the Città di Castello-Sansepolcro basin (CSB) of the northern Apennines of Italy. New field data from the geological survey of the Carta Geologica d' Italia (CARG project) define the surface geometry of the normal fault system and lead to an interpretation of the CROP 03 deep-crust seismic reflection profile (Castiglion Fiorentino-Urbania segment), with particular attention paid to the geometry of the Plio-Quaternary extensional structures. Surface and sub-surface geological data are integrated with instrumental and historical seismicity in order to define the seismotectonics of the area. Low-angle east-dipping reflectors are the seismic expression of the well-known Altotiberina Fault (AF), a regional extensional detachment on which both east- and west-dipping high-angle faults, bounding the CSB, sole out. The AF breakaway zone is located ˜ 10 km west of the CSB. Within the extensional allochthon, synthetic east-dipping planes prevail. Displacement along the AF is ˜ 4.5 km, which agrees with the cumulative offset due to its synthetic splays. The evolution of the CSB has mainly been controlled by the east-dipping fault system, at least since Early Pleistocene time; this system is still active and responsible for the seismicity of the area. A low level of seismic activity was recorded instrumentally within the CSB, but several damaging earthquakes have occurred in historical times. The instrumental seismicity and the intensity data points of the largest historical earthquakes (5 events with maximum MCS intensity of IX to IX-X) allow us to propose two main seismogenic structures: the Monte Santa Maria Tiberina (Mmax = 5.9) and Città di Castello (Mmax up to 6.5) normal faults. Both are synthetic splays of the AF detachment, dipping to the NE at moderate (45-50°) to low (25-30°) angles and cutting the upper crust up to the surface. This study suggests that low-angle normal faults (at least

  7. Active faulting Vs other surface displacing complex geomorphic phenomena. Case studies from a tectonically active area, Abruzzi Region, central Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Lo Sardo, Lorenzo; Gori, Stefano; Falcucci, Emanuela; Saroli, Michele; Moro, Marco; Galadini, Fabrizio; Lancia, Michele; Fubelli, Giandomenico; Pezzo, Giuseppe

    2016-04-01

    could be possible to infer the genesis of the scarps as due to complex tectono-karstic phenomena. As for case (ii), our ongoing analyses are aimed to analyze the tectonic "significance" of some closed depressions, up to 4 km long and to 0,5-1 km large, that occur along the south-western slope of the Gran Sasso Range. All these small depression are NW-SE trending. As already described by Bosi et al. (1989), Galadini and Giuliani (1993), D'Agostino et al. (1998), Falcucci et al. (2015), these closed depressions are bounded by scarps carved onto the carbonate bedrock and, subordinately, onto early Quaternary slope deposits, reaching height of up to 5 m. These scarps are preferentially NE dipping, even if in few cases some SW dipping scarp are also present . The field work has permitted to attest that these scarps are related to shear planes that that displaced two subsequent of Early Pleistocene breccias formations (the Valle Valiano Fm. and Fonte Vedice Fm.; Bosi e Bertini, 1993; D'agostino et al., 1997). A paleoseismological trench was also performed across one of these scarps, attesting the activity of these shear planes also in recent times, providing indications result about the deformation style. Reference Bertini, T., & Bosi, C. (1993). La tettonica quaternaria della conca di Fossa (L'Aquila). Il Quaternario, 6(2), 293-314. Bertini, T., Bosi, C., & Galadini, F. (1989). La conca di Fossa-S. Demetrio dei Vestini. CNR, Centro di Studio per la Geologia Tecnica, ENEA, PAS in Elementi di tettonica pliocenicoquaternaria ed indizi di sismicita olocenica nell'Appennino laziale-abruzzese, Societa Geologica Italiana, L'Aquila, 26-58. Bosi, C., & Bertini, T. (1970). Geologia della media valle dell'Aterno. Memorie Società Geologica Italiana, 9(4), 719-777. D'Agostino, N., F. Speranza, & R. Funiciello., (1997) "Le Brecce Mortadella dell'Appennino Centrale: primi risultati di stratigrafia magnetica." Il Quaternario10.2: 385-388. D'Agostino, N., Chamot-Rooke, N., Funiciello, R

  8. Active faulting Vs other surface displacing complex geomorphic phenomena. Case studies from a tectonically active area, Abruzzi Region, central Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Lo Sardo, Lorenzo; Gori, Stefano; Falcucci, Emanuela; Saroli, Michele; Moro, Marco; Galadini, Fabrizio; Lancia, Michele; Fubelli, Giandomenico; Pezzo, Giuseppe

    2016-04-01

    could be possible to infer the genesis of the scarps as due to complex tectono-karstic phenomena. As for case (ii), our ongoing analyses are aimed to analyze the tectonic "significance" of some closed depressions, up to 4 km long and to 0,5-1 km large, that occur along the south-western slope of the Gran Sasso Range. All these small depression are NW-SE trending. As already described by Bosi et al. (1989), Galadini and Giuliani (1993), D'Agostino et al. (1998), Falcucci et al. (2015), these closed depressions are bounded by scarps carved onto the carbonate bedrock and, subordinately, onto early Quaternary slope deposits, reaching height of up to 5 m. These scarps are preferentially NE dipping, even if in few cases some SW dipping scarp are also present . The field work has permitted to attest that these scarps are related to shear planes that that displaced two subsequent of Early Pleistocene breccias formations (the Valle Valiano Fm. and Fonte Vedice Fm.; Bosi e Bertini, 1993; D'agostino et al., 1997). A paleoseismological trench was also performed across one of these scarps, attesting the activity of these shear planes also in recent times, providing indications result about the deformation style. Reference Bertini, T., & Bosi, C. (1993). La tettonica quaternaria della conca di Fossa (L'Aquila). Il Quaternario, 6(2), 293-314. Bertini, T., Bosi, C., & Galadini, F. (1989). La conca di Fossa-S. Demetrio dei Vestini. CNR, Centro di Studio per la Geologia Tecnica, ENEA, PAS in Elementi di tettonica pliocenicoquaternaria ed indizi di sismicita olocenica nell'Appennino laziale-abruzzese, Societa Geologica Italiana, L'Aquila, 26-58. Bosi, C., & Bertini, T. (1970). Geologia della media valle dell'Aterno. Memorie Società Geologica Italiana, 9(4), 719-777. D'Agostino, N., F. Speranza, & R. Funiciello., (1997) "Le Brecce Mortadella dell'Appennino Centrale: primi risultati di stratigrafia magnetica." Il Quaternario10.2: 385-388. D'Agostino, N., Chamot-Rooke, N., Funiciello, R

  9. 3D modelling of the Austroalpine-Penninic collisional wedge of the NW Alps: dataset management and preliminary results

    NASA Astrophysics Data System (ADS)

    Monopoli, Bruno; Bistacchi, Andrea; Bertolo, Davide; Dal Piaz, Giovanni; Gouffon, Yves; Massironi, Matteo; Sartori, Mario; Vittorio Dal Piaz, Giorgio

    2016-04-01

    considered as a sort of pseudo-stratigraphy, since they are the oldest feature that can be traced continuously at the map scale. For this reason we have developed a set of attributes identifying the tectonic and lithological units (a "legend"), implemented both in the GIS database and in the 3D models, which at the same time is compatible with the data structure of 3D modelling packages like Move and Skua/Gocad, and allows tracing the complex hierarchic classification of the units mapped in the GIS. This allows for the almost automatic and consistent two-way transfer of data between the GIS and geomodelling environments. E.g. results of 3D modelling, which is based on input data originally stored in the GIS, will eventually be transferred back to the GIS. The results of this study, which are preliminarily presented here, will open new opportunities to study the collision- and subduction-related nappe architecture and kinematics with younger deformations removed, and will eventually lead (with additional studies) to a step-by-step retrodeformation supported by modern technologies, following the path traced by Argand at the beginning of the 20th century. Argand E. 1909. L'exploration géologique des Alpes pennines centrales. Bull. Soc. Vaudoise Sci. Nat., 45, 217-276. Argand A. 1911. Les nappes de recouvrement des Alpes pennines et leurs prolongements structuraux. Mat. Carte Géol. Suisse, 31, 25. Argand A. 1916. Sur l'arc des Alpes occidentales. Eclogae Geol. Helv., 14, 145-191. Franchi S., Mattirolo E., Novarese V., Stella A. & Zaccagna D. 1908. Carta geologica delle Alpi Occidentali alla scala 1:400.000. Regio Ufficio Geologico, Roma. Gerlach H. 1869. Die Penninischen Alpen. N. Denkschr. Schweiz. Natf. Ges., 23, 132. Gerlach H. 1871. Das Suedwestliche Wallis. Beitraege Geol. Karte Schweiz, 9, 175. Giordano F. 1869. Sulla orografia e sulla geologica costituzione del Gran Cervino. Atti R. Acc. Sci. Torino, 4, 304-321.

  10. The Campi Flegrei caldera-hosted high-temperature and high-saline geothermal system in the Southern Italy: the implication of the geothermal resource as derived by the present state of the knowledge through 70 years of volcanological, structural, petrolog

    NASA Astrophysics Data System (ADS)

    Piochi, M.; Di Vito, M. A.; Mormone, A.; De Natale, G.; Tramelli, A.; Troise, C.; Carlino, S.

    2012-04-01

    The Campi Flegrei caldera (Italy) hosts a geothermal system characterized by: i) high thermal gradient (temperature up to 420°C at 3050 m b.s.l.), ii) high temperature (up to ~90-150°C at very shallow depth) fumaroles, iii) multiple meteoric to brine (TDS up to 33 g•l-1; temperature up to 95 °C) aquifers and iv) at least 1500 tonnes per day of CO2 emissions. This area is highly urbanized despite the repeated occurrence of ground deformation phenomena accompanied by seismicity with volcano-tectonic and long-period micro-earthquakes. The caldera has been widely studied by geologist and geophysicists. In particular, since '40s, the caldera has drawn scientific interest for its geothermal capability inducing the companies AGIP (Azienda Geologica Italiana Petroli) and SAFEN (Società Anonima Forze Endogene Napoletane) to drill more than one hundred 80-to-3100 m deep wells. However this experience did not reach the exploitation phase due to technological and communication problems. The geothermal potential (thermal and electric) is evaluated of about 6 GWy. The recent Campi Flegrei Deep Drilling Project [De Natale and Troise, 2011], sponsored by the International Continental Scientific Drilling Program, foresees the realization of medium-to-deep wells in the caldera with the ambition of stimulating interest in geothermal energy exploitation and technology development and, in addition of installing downhole monitoring systems. The geological knowledge of the area is the benchmark for the drilling sites selection. We reconstructed a multi-disciplinary conceptual model updated on the basis of the most recent scientific results and findings. In particular, the constrains (the most important are listed in brackets) comes from: i) boreholes (litho-stratigraphy, aquifer location, depth-related temperature), ii) fieldwork (stratigraphy, location of structural fractures and eruption vents), iii) petrology and melt inclusions (pressure and temperature of magma with

  11. A helium isotope cross-section study through the Vulture line, southern Apennines

    NASA Astrophysics Data System (ADS)

    Caracausi, Antonio; Martelli, Mauro; Nuccio, Mario; Paternoster, Michele; Stuart, Finlay

    2013-04-01

    present at Mt. Vulture volcano and the surrounding area, while it decreases toward the Tyrrhenian sea. This may be due to different causes: a) volatiles degassing from near-surface melts beneath Mt. Vulture are quantitatively dominant with respect to crustal gases, in contrast to gas emissions located close to the peri-Thyrrenian area and/or b) the 3He/4He of the peri-Tyrrhenian magmas is expected to be lower than 6 Ra. Our data suggest the active role of Vulture line (lithospheric faults) to transfer towards the surface mantle-derived fluids from magmatic bodies or from asthenospheric upwelling of hot, possible molten material (Ökeler et al., 2009) accumulated to the base of the crust. Buettner, A., Principe, C., Villa, I.M., Bocchini, D., 2006. 39Ar-40Ar geochronology of Monte Vulture. In: Principe, C. (Ed.), La Geologia del Monte Vulture. Grafiche Finiguerra, Lavello, Italy, pp. 73-86. Doglioni, C., Mongelli, F., Pieri, P., 1994. The Puglia uplift (SE Italy): an anomaly in the foreland of the Apenninic subduction due to buckling of a thick continental lithosphere. Tectonics 13 (5), 1309-1321. D'Orazio, M., Innocenti, F., Tonarini, S., Doglioni, C., 2007. Carbonatites in a subduction system: the Pleistocene alvikites from Mt. Vulture (southern Italy). Lithos 98, 313-334. Ökeler, A., Gu, Y.J., Lerner-Lam, A., Steckler, M.S., 2009. Seismic structure of the southern Apennines as revealed by wave form modelling of regional surface waves. Geophysical Journal International 178, 1473-1492. Schiattarella, M., Beneduce, P., Giano, S.I., Giannandrea, P., Principe, C., 2005. Assetto strutturale ed evoluzione morfotettonica quaternaria del vulcano del Monte Vulture (Appennino Lucano). Bollettino della Societa Geologica Italiana 124, 543-562.

  12. Sediment yield estimation in mountain catchments of the Camastra reservoir, southern Italy: a comparison among different empirical methods

    NASA Astrophysics Data System (ADS)

    Lazzari, Maurizio; Danese, Maria; Gioia, Dario; Piccarreta, Marco

    2013-04-01

    using sediment storage in reservoirs provides a good opportunity: i) to test the reliability of the empirical methods used to estimate the sediment yield; ii) to investigate the catchment dynamics and its spatial and temporal evolution in terms of erosion, transport and deposition. References Ciccacci S., Fredi F., Lupia Palmieri E., Pugliese F., 1980. Contributo dell'analisi geomorfica quantitativa alla valutazione dell'entita dell'erosione nei bacini fluviali. Bollettino della Società Geologica Italiana 99: 455-516. Mitasova H, Hofierka J, Zlocha M, Iverson LR. 1996. Modeling topographic potential for erosion and deposition using GIS. International Journal of Geographical Information Systems 10: 629-641. Renard K.G., Foster G.R., Weesies G.A., McCool D.K., Yoder D.C., 1997. Predicting soil erosion by water: a guide to conservation planning with the Revised Universal Soil Loss Equation (RUSLE), USDA-ARS, Agricultural Handbook No. 703.

  13. Early Pleistocene climate cycles in continental deposits of the Lesser Caucasus of Armenia inferred from palynology, magnetostratigraphy, and 40Ar/39Ar dating

    NASA Astrophysics Data System (ADS)

    Joannin, Sebastien; Cornée, Jean-Jacques; Münch, Philippe; Fornari, Michel; Krijgsman, Wout; Nahapetyan, Samuel; Gabrielyan, Ivan; Ollivier, Vincent; Roiron, Paul; Chataignier, Christine

    2010-05-01

    obliquity orbital parameter. The influence of precession could not be established from the Shamb data. Pollen and macroflora both indicate that glacial periods were cold and dry and that interglacials were warm with local humidity. The early Pleistocene climatic model for Western Asia is thus similar to the climatic model for the Mediterranean area. Bruch, A., Gabrielyan, I.G., 2002. Quantitative data of the Neogene climatic development in Armenia and Nakhichevan. Acta Universitatis Carolinae - Geologica 46, 41-48. Joannin, S., Cornée, J.J., Münch, P., Fornari, M., Vasiliev, J., Krijgsman, W., Nahapetyan, S., Gabrielyan, Y., Ollivier, V., Roiron, P., Chataignier, C. In press. Early Pleistocene climatic cycles in continental deposits of the Lesser Caucasus of Armenia inferred from palynology, magnetostratigraphy, and 40Ar/39Ar dating. Earth and Planetary Science Letters. Mitchell, J., Westaway, R., 1999. Chronology of Neogene and Quaternary uplift and magmatism in the Caucasus: constraints from K-Ar dating of volcanism in Armenia. Tectonophysics 304, 157-186.

  14. Lichenometry dating of rock collapse related to the great Lisbon Earthquake (1755) at the SE part of Spain

    NASA Astrophysics Data System (ADS)

    Perez-Lopez, Raul; Rodriguez-Pascua, Miguel Angel; Silva, Pablo G.; Bischoff, James L.; Owen, Lewis A.; Giner-Robles, Jorge L.; Díez-Herrero, Andres

    2010-05-01

    by the great Lisbon Earthquake of 1755, suggesting an ESI macroseismic intensity ranging between VII and VIII (Michetti et al., 2007) from a locality located 660 km eastward away from the city of Lisbon. This value is in contrast with the EMS intensity of V-VI estimated by Martínez-Solares (2001). Martínez-Solares, J. M. (2001): Los efectos en España del Terremoto de Lisboa (1 de noviembre de 1755). Ed. Dirección General del Instituto Geográfico Nacional. Madrid. 756 p. (In Spanish). Michetti, et al. (2007): Intensity Scale ESI 2007. Memoria Descriptiva Carta Geologica Italiana, 74: 41.

  15. Helium and carbon isotope systematics of Rungwe geothermal gases and fluids; southern Tanzania

    NASA Astrophysics Data System (ADS)

    Barry, P. H.

    2009-12-01

    P. H. BARRY1*, D. R. HILTON1, T. P. FISCHER2, J. M. DE MOOR2, F. MANGASINI3 C. RAMIREZ4 1 Geosciences Research Division, Scripps Institution of Oceanography, UCSD, La Jolla, California 92093-0244, USA (*Correspondence: pbarry@ucsd.edu) 2 Department of Earth and Planetary Sciences, MSC 03 2040, 1 University of New Mexico, Albuquerque, New Mexico 87131-0001, USA. 3 Department of Mining and Mineral Processing Engineering, University of Dar Es Salaam, PO Box 35131, Dar Es Salaam, Tanzania. 4 Centro de Investigaciones en Ciencias Geologicas, Escuela Centroamericana de Geologia, Universidad de Costa Rica. The East African Rift (EAR) is the largest modern example of continental rifting, extending from the Afar depression in the north to the Rungwe region in southern Tanzania. EAR volcanism is attributed to the presence of one or more mantle plumes [1]. Late Miocene to recent volcanism and geothermal activity mark the Rungwe region [2], with mafic eruptions as recently as 200 years ago. Our aim is to delineate the southern geographical extent of plume influence on the propagating EAR by investigating the He-CO2 characteristics of geothermal fluids in the Rungwe region. We report new helium (He) and carbon (C) isotopes (3He/4He, δ13C) and relative abundance (CO2/3He) characteristics for a suite of 20 geothermal gas and fluid samples from 11 different localities in the Rungwe region. He-isotopes are in good agreement with previous reports [3], and range from ~1 RA to ~7 RA (MORB-like values), indicating admixture between upper mantle He and variable proportions of radiogenic He. C-isotopes ranges from -2.8 to -6.5 ‰ (vs. PDB) with all falling in the MORB range (~4.5 ± 2‰). CO2/3He ratios vary over 5 orders of magnitude from ~3 x 10^9 (MORB-like) to higher values (up to ~3 x 10^13) normally associated with crustal lithologies. Taken together, the He-CO2 data can be explained by 2-component mixing of a deep-seated mantle source with crustal component(s). There are no

  16. Microinclusion of Lower-Mantle Rock in Diamond

    NASA Astrophysics Data System (ADS)

    Kaminsky, Felix; Wirth, Richard

    2014-05-01

    A microinclusion of a rock fragment was identified within one of the diamonds from the Rio Soriso placer deposit in the Juina area, Brazil. It is composed of iron carbide, magnesiowüstite and two orthorhombic, postspinel phases, Fe-Mg-Cr and Ca-Cr oxides. All mineral grains are closely intergrown, demonstrating their single-stage origin, except iron carbide, which is partly resorped that implies its early crystallization. Diffraction patterns of iron carbide grains reveal two mineral species, nitrogen-containing analogues of chalypite Fe7C3 (or Fe2C) [1] and yarlongite Fe9C4 [2]. They contain up to 17.5 at.% of N in the cation part (N/(C+N) = 0.47) and should be considered as nitrocarbides. In addition to N, admixtures of O and Si present in these mineral species. Magnesiowüstite has, in its cation composition, 47.75-67.16 at.% Fe, 36.72-47.75 at.% Mg, and minor admixtures of Mn and Cr. Among the two new oxides with orthorhombic structure, one is a polymorph of chromite (Fe2+,Mg,Mn) (Cr,Fe3+,Al,V)2O4, which is new in terrestrial environment. It is analogues to xieite, found in the Suizhou meteorite [3], but strongly enriched in Fe. The other orthorhombic mineral fits the stoichiometry Ca(Cr,Fe3+)2O4. This compound is new in the natural environment; the CaCr2O4 postspinel phase is known only as a synthetic compound [4]. The studied association was formed within the lower mantle at pressure conditions above 40 GPa (that correspond to the formation of CaTi2O4 [5]). The presence of magnesiowüstite and chalypite suggests the rock origin in the lower part of the lower mantle. References: Kaminsky, F.V., Wirth, R. (2011) Iron carbide inclusions in lower-mantle diamond from Juina, Brazil. Canadian Mineralogist 49(2), p. 555-572. Shi, N., Bai, W., Li, G., Xiong, M., Fang, Q., Yang, J., Ma, Z., Rong, H. (2009) Yarlongite: A new metallic carbide mineral. Acta Geologica Sinica 83(1), 52-56. Chen, M., Shu, J., Mao, H.-k. (2008) Xieite, a new mineral of high-pressure FeCr2O4

  17. Lower Cretaceous Puez key-section in the Dolomites - towards the mid-Cretaceous super-greenhouse

    NASA Astrophysics Data System (ADS)

    Lukeneder, A.; Halásová, E.; Rehákova, D.; Józsa, Š.; Soták, J.; Kroh, A.; Jovane, L.; Florindo, F.; Sprovieri, M.; Giorgioni, M.; Lukeneder, S.

    2012-04-01

    of Earth Sciences, 103/1, 138-158. Lukeneder A. 2008. The ecological significance of solitary coral and bivalve epibionts on Lower Cretaceous (Valanginian-Aptian) ammonoids from the Italian Dolomites. Acta Geologica Polonica, 58/4, 425-436. Lukeneder, A., Aspmair, C. 2006. Startigraphic implication of a new Lower Cretaceous ammonoid fauna from the Puez area (Valanginaian - Aptian, Dolomites, Southern Alps, Italy). Geo.Alp, 3, 55-91.

  18. The Southern Part of the Southern Volcanic Zone (SSVZ; 42-46S) of the Andes: History of Medium and Large Explosive Holocene Eruptions

    NASA Astrophysics Data System (ADS)

    Stern, C. R.; Naranjo, J. A.

    2008-12-01

    Michinmahuida, because no evidence of tephra from this eruption is found around the Chaitén volcano. The younger and larger of these eruptions (MIC2) generated rhyolites similar in composition to those erupted from Chaitén, suggesting some possible relation between the Michinmahuida and Chaitén magma plumbing systems. Chaitén erupted at approximately <9370 BP based on dating of charcoal within the pyroclastic flow deposit produced by this eruption. This deposit decreases from 3.5 m thick 10 km north of the volcano to 1.5 m thick 30 km north of the volcano, and is covered by a 1.65 to 0.3 m thick tehra fall deposit of rhyolite pumice capped by a thin layer of dark mafic scoria. We consider the pre-May 2008 rhyolite obsidian dome to have formed at this time, or at least before 5610 BP, the age of pre-historic occupation sites with obsidian artifacts fashioned from this obsidian (Stern et al. 2002). Both the thickness of this deposit and the size of the dome in the crater prior to the May 2008 eruption suggest that the current event is not yet as large as the 9370 BP event, which ended with the eruption of a more mafic magma. Thus the current eruption cycle may have a way to go yet before it is complete. Naranjo et al. 1993, Boletin No 44, SERNAGEOMIN, 50 p. Naranjo and Stern 1998, Bull Volcanology 59: 291-306. Naranjo and Stern 2004, Revista Geologica de Chile 31: 225-240. Stern et al. 2002, Anales del Intituto de la Patagonia 30: 167-174.

  19. Landslide hazard prediction in the North-Eastern Apennines (Italy)

    NASA Astrophysics Data System (ADS)

    Disperati, L.; Guastaldi, E.; Rindinella, A.

    2003-04-01

    training dataset of occurrences and a test dataset, a cross validation is made. The valuation both for flows and slides was performed through Prediction Rate Curves (PRC). By utilising the occurrences of the test dataset, PRC derived from the relation between CF trend in the whole area (cumulative percentage), portion of total area and number of landslides. As result, engineering geology can be indicated as the dominant factor for PRC of flows; likewise engineering geology, land use and RBS combination is the more effective combination. On the other side, slope and aspect resulted less determinative in best PRC trend. Moreover, the combination of engineering geology and slope allowed the computation of best PRC for landslide. References CARMIGNANI L. (2001): Realizzazione della cartografia geologica e geotematica e dei relativi supporti informatici alla scala 1/10.000 -- Progetto 1 -- Zona Nord. Progetti strumentali alla funzione di ricostruzione. Interventi strutturali comunitari obiettivo 5b -- Misura 3.1.4 Azioni di ricostruzione e recupero del tessuto urbano infrastrutturale nei territori colpiti dal sisma (Azione 7). Contratto tra la Regione Marche -- Servizio Urbanistica e Cartografia e l'Università degli Studi di Siena. Rapporto Finale. Università degli Studi di Siena, Dipartimento di Scienze della Terra, Dicembre 200 1, pp. 6 I. CHUNG C. J. (1999): Prediction models in spatial data analysis for landslide hazard mapping -- Natural Resources Canada, Geological Survey of Canada-Mineral Resources Division-Spatial Data Analysis Laboratory, http://www.nrcan.gc.ca/gsc/mrd/sdalweb/landslides/index.htm. CHUNG C. J., FABBRI A.G. (1993): The representation of geoscience information for data integration. Non-renewable Resources, v. 2., n. 3, pp. 1 22-139. CHUNG C. J., FABBRI A.G., VAN WESTEN C.J (1995).- Multivariate regression analysis for landslide hazard zonation. In Carrara, A. and Guzzetti, F., eds.: "Geographical Information Systems in Assessing Natural Hazards

  20. FREEWAT: an HORIZON 2020 project to build open source tools for water management.

    NASA Astrophysics Data System (ADS)

    Rossetto, Rudy; Borsi, Iacopo; Foglia, Laura

    2015-04-01

    Geologica Italiana Volume 24, 282-283

  1. On the origin of zebra textures in Mississippi Valley-Type Pb-Zn Deposits with a special emphasis on the San Vicente Mine, Peru

    NASA Astrophysics Data System (ADS)

    Kelka, Ulrich; Koehn, Daniel

    2014-05-01

    grain boundaries move according to a rate law based on dissolution-precipitation processes as a function of differences in surface energy. Layered distributions of particle densities are initially set as a background. With this simple simulation of grain growth influenced by particle distributions we show, that this process is able to develop structural patterns that are very similar to those present in the natural samples from the San Vicente Mine in Peru. References BONS P D, KOEHN D, and JESSELL W (2008) Microdynamic Simulation. Springer-Verlag Berlin Heidelberg FONTBONTé L (1993) Self-organization fabrics in carbonate-hosted ore deposits: the example of diagenetic crystallization rhythmites (DCRs), In: Current research in geology applied to ore deposits. Proceedings of the Second Biennial SGA Meeting, Granada, Spain, p. 11 -14 MERINO E, CANALS A, and FLECHTER R C (2006) Genesis of self-organized zebra textures in burial dolomites: Displacive veins, induced stress, and dolomitization. Geologica Acta, Vol. 4 No. 3, p. 383-393

  2. Deep seated gravitational slope deformations and large landslides: implications on landslide hazard of urban areas and coastal erosion phenomena of Mount Poro headland

    NASA Astrophysics Data System (ADS)

    Guerricchio, A.; Simeone, V.

    2012-04-01

    square kilometers. Its movement towards NW produced a typical coastline, with a strong progradation towards NW and W from Punta della Tonnara to Parghelia and up to Fiumara della Ruffa (WSW of Tropea). The DSGSD involves the granitic bedrock as well as the transgressive Tortonian deposits, made by sands with the presence of Clypeasters, which are topped by arenaceous banks, for a total depth of 150 m. DSGSDs involving granitic rocks were probably due to more deformable lithotypes, like biotite schists, which work as substratum of granitic rocks at a not very deep depth, like in other areas of Calabria. Finally, the slow sliding towards N and NW of the landslide shapes the coast like a bow, thus causing strong erosion phenomena of the coastline. Ietto A & Calcaterra D. (1988). Deformazioni gravitative profonde e tettonica presso Tropea (M.te Poro, Calabria)", Memorie della Societa Geologica Italiana, 41, pp. 911-915, Rome, Italy. Guerricchio A. (2000). La fragilità del territorio dell'Italia centro-meridionale desumibile da immagini da satellite. X Congr. Naz. dei Geologi. International Conference: Il Territorio fragile; I, 443-482, Rome, Italy.

  3. Benthic foraminiferal and isotopic patterns during the Early Eocene Climatic Optimum (Aktulagay section, Kazakhstan)

    NASA Astrophysics Data System (ADS)

    Deprez, Arne; Tesseur, Steven; Stassen, Peter; D'haenens, Simon; Steurbaut, Etienne; King, Christopher; Claeys, Philippe; Speijer, Robert P.

    2015-04-01

    basin development. Akhmetiev and Beniamovskii (2009) also found a transition from a paratropical to a monsoonal (seasonal) climate, based on simultaneous land vegetation changes. This change coincides with the peak of the EECO, as indicated by its position close to the base of NP13 and rising δ13Cepibenthic values from 52 to 50 Ma. Although it is tempting to link the observed patterns to climate change, we cannot exclude that changing paleogeography and variable connections between the Peri-Tethys and the Tethys, Atlantic and the Arctic Oceans largely determined the long-term period of dysoxia and anoxia during deposition of the sapropel beds at the Peri-Tethyan seafloor. Akhmetiev, M.A., Beniamovskii, V.N., 2009. Geologica Acta 7, 297-309. King, C. et al., 2013. Stratigraphy 10, 171-209.

  4. Geologic map of Mészáros revisited: Pioneering tectonic mapping of the Transdanubian Range in the early 1980s

    NASA Astrophysics Data System (ADS)

    Zámolyi, A.; Horváth, F.; Kovács, G.; Timár, G.; Székely, B.

    2009-04-01

    the faults mapped by Mészáros (1983) coincide fairly well with their microtectonic measurements. TR is nowadays interpreted as the uppermost Cretaceous thrust sheet of the Alpine nappes based on the interpretation of seismic surveys (Rumpler & Horváth, 1988; Horváth, 1993) and microtectonic measurements (Kiss & Fodor, 2007). We integrated the map into a GIS environment in order to evaluate the spatial accuracy of tectonic features and deformation style in the study area. Georeferencing was based upon control points applying rubber sheeting. Geological formations were digitized as polygons with their respective attributes (colour- or numerically coded). Three different categories of bounding elements are represented on the map: established, supposed and covered by younger geologic formations. Mészáros put a major emphasis on tectonic features, using 21 different line-types for representation. Digital terrain analysis methods using a 10 m DTM reveal a good correlation of the fault pattern with geomorphologic features, especially in the category of confirmed strike-slip faults. The connection of tectonic elements with the topography is a very anticipatory way of thinking for the early 1980s that became widely accepted by the end of the century. Csontos, L., Tari, G., Bergerat, F., Fodor, L. 1991. Tectonophysics, 199, 73-91. Horváth, F. 1993. In: Cloething, S., Sassi, W. & Horváth, F. (eds.) Tectonophysics, 226, 333-358. Kiss, A., Fodor, L. I. 2007. Geologica Carpathica, 58(5), 465-475. Mészáros, J. 1983. Ann. Rep. Hung. Geol. Inst. 1981, 485-502. Prinz, Gy. 1926. Danubia könyvkiadó, Pécs, 202 p. Rumpler, J., Horváth, F. 1988. In: L.H. Royden and F. Horváth (eds.) AAPG Mem. 45, Tulsa, Okl., 153-169p. Uhlig, V. 1907. Sitz. Ber. Akad. Wiss., math.- nat., Kl. 116(1), 871-982.

  5. The chronology of the India-Asia collision

    NASA Astrophysics Data System (ADS)

    Garzanti, Eduardo; Hu, Xiumian

    2016-04-01

    volcaniclastic to ophioliticlastic fluvio-deltaic sediments derived from the uplifting Asian margin (Najman et al., 2010; Hu et al., 2012). Tethys Himalayan successions were finally involved in tectonic deformation and very low-grade metamorphism around Lutetian times (47-44 Ma; Garzanti and Brignoli, 1989; Bonhomme and Garzanti, 1991). CITED REFERENCES Bonhomme M., Garzanti E. 1991. Geologic Alpine Memoirs 16:15-16. DeCelles P.G., Kapp P., Gehrels G.E., Ding L. 2014. Tectonics 33:824-849. Garzanti E., Baud A., Mascle G. 1987. Geodinamica Acta 1:297-312. Garzanti E., Brignoli G. 1989. Eclogae). Eclogae Geologicae Helvetiae 82:669-684. Garzanti E, Hu X. 2015. Gondwana Research 28:165-178. Hu X., Sinclair H.D., Wang J., Jiang H., Wu F. 2012. Basin Research 24:520-543. Hu X., Garzanti E., Moore T., Raffi I. 2015. Geology 43:859-862. Li J., Hu X., Garzanti E., An W. Wang J. 2015. Journal of Asian Earth Sciences, 104:39-54. Najman, Y., Appel, E., Boudagher-Fadel, M., Bown, P., Carter, A. et al. 2010. Journal of Geophysical Research 115:B12416 doi:10.1029/2010JB007673. Wu F.Y., Ji W.Q., Wang J.G., Liu C.Z., Chung S.L., Clift P.D. 2014. American Journal of Science 314:548-579.

  6. Assessment of local seismic response of the Stracciacappa maar (Central Italy)

    NASA Astrophysics Data System (ADS)

    Moscatelli, Massimiliano; Simionato, Maurizio; Gaudiosi, Iolanda; Sottili, Gianluca; Pagliaroli, Alessandro; Sirianni, Pietro; Pileggi, Domenico; Avalle, Alessandra; Giallini, Silvia; Razzano, Roberto; Mancini, Marco; Vignaroli, Gianluca; Piscitelli, Sabatino; Bellanova, Jessica; Calamita, Giuseppe; Perrone, Angela; Lanzo, Giuseppe

    2016-04-01

    properties of soils, the cyclic soil behavior was investigated in laboratory through the Double Specimen Direct Simple Shear device. Particular care was given to organic clays within the lacustrine deposits, which show a stronger linearity and lower damping ratio with respect to inorganic clays of similar plasticity. The collected geological-geophysical dataset suggests the coalescence of several eruptive centres localized at different depths and laterally distributed within the present-day Stracciacappa maar. Data are currently processed for subsequent 2D and 3D numerical simulations of site effects. REFERENCES De Rita D. and Zanetti G., 1986. I centri esplosivi di Baccano e di Stracciacappe (Sabatini orientali, Roma): analogie e differenze della modellistica esplosiva in funzione del grado di interazione acqua/magma. Memorie della Società Geologica Italiana, 35, 689-697. Marra F., Sottili G., Gaeta M., Giaccio B., Jicha B., Masotta M., Palladino D.M., Deocampo D.M., 2014. Major explosive activity in the Monti Sabatini Volcanic District (central Italy) over the 800-390 ka interval: geochronological-geochemical overview and tephrostratigraphic implications Sottili G., Palladino D.M., Marra F., Jicha B., Karner D.B., Renne P., 2010. Geochronology of the most recent activity in the Sabatini Volcanic District, Roman Province, central Italy. Journal of Volcanology and Geothermal Research, 196, 20-30.

  7. Cu isotope variability in Bavariás largest Cu-Zn deposit in Kupferberg (NE Bavaria, Germany)

    NASA Astrophysics Data System (ADS)

    Höhn, Stefan; Frimmel, Hartwig E.; Debaille, Vinciane; Debouge, Wendy

    2016-04-01

    contrast, undoubtedly supergene native copper and malachite yielded δ65Cu of as much as 1.75 ‰ which is in line with observations on supergene Cu mineralization elsewhere (Mathur and Fantle 2015). Our new results suggest a principle phase of hypogene Cu-mineralization, possibly related to Variscan metamorphic fluid circulation, with subsequent supergene Cu-mineralization due to interaction with groundwater having been subordinate. Literature Ikehata, K., Notsu, K., Hirata, T. (2011): Copper isotope characteristics of copper-rich minerals from Besshi-Type volcanogenic massive sulfide deposits, Japan, determined using a femtosecond LA-MC-ICP-MS.- Economic Geology 106, 307-316. Markl, G., Lahaye, Y., Schwinn, G. (2006): Copper isotopes of redox processes in hydrothermal mineralization.- Geochimica et Cosmochimica Acta 70, 4215-4228. Mathur, R. & Fantle, M.S. (2015): Copper isotopic perspectives on supergene processes: Implications for the global Cu cycle.- Elements 11, 323-329. Urban, H. & Vaché, R. (1972): Die Kupfererzlagerstätte von Kupferberg-Wirsberg (Oberfranken) im Lichte neuer Aufschlüsse.- Geologica Bavarica 65, 74-106.

  8. Neogene transtensional brittle tectonics in the Lepontine D

    NASA Astrophysics Data System (ADS)

    Allanic, C.; Sue, C.; Champagnac, J.-D.

    2009-04-01

    -parallel extensional phase, at least in the Lepontine Dome. We propose a kinematic model for the Central Alps in which the emplacement of the Lepontine Dome is driven by a pull-apart-like process controlled by the counterclockwise rotation of the Apulian indenter. This model refers to the paleostress field we documented and to kinetics of the main faults bounding the dome. Associated to these processes, lateral escape linked to the Apulia indentation/rotation would have enhanced the global extensional scheme of the Lepontine Dome. REFERENCES Allanic, C., et al. (2006), A paleo-seismogenic Lepontine dome? New insights from pseudotachylytes-generating faults, Geochimica et Cosmochimica Acta, Vol. 70 (18), Suppl. 1, p9 Goldschmidt conf. Melbourne. Bistacchi, A., and Massironi M. (2000), Post-nappe brittle tectonics and kinematic evolution of the north-western Alps: an integrated approach, Tectonophysics, 327, 267-292. Champagnac, J. D., Sue, C., Delacou, B., Burkhard, M. (2006), Miocene orogen-parallel extension in the inner Western Alps revealed by dynamical fault analyses, Tectonics, 25, 1-26. Ciancaleoni, L., and Marquer D. (2008), Late Oligocene to early Miocene lateral extrusion at the eastern borders of the Lepontine dome of the Central Alps (Bergell and Insubric areas, Eastern Central Alps), Tectonics, 27, TC4008, doi:10.1029/2007TC002196, 2008. Grosjean, G., Sue, C., Burkhard, M. (2004), Late Neogene brittle extension in the vicinity of the Simplon fault zone, central Alps, Switzerland., Eclogae Geologicae Helvetiae, 97, 33-46.

  9. Tectonic mélanges and the exhumation of HP ophiolites: a case-study from the Ligurian Alps

    NASA Astrophysics Data System (ADS)

    Federico, Laura; Crispini, Laura; Scambelluri, Marco; Capponi, Giovanni; Malatesta, Cristina

    2010-05-01

    fluids released from the slab (e.g. Gerya et al., 2002). Here a forced flow inside serpentinites sampled different HP lenses from different depths and forced them to flow towards surface. The pattern of the studied mélange could be applicable at larger scale in the Ligurian Alps, where various HP units may be larger-scale equivalents of blocks, and may have been exhumed in a subduction channel inside serpentinites. Different units of the Voltri massif display metamorphic peaks at conditions ranging from eclogite- to blueschist-facies and available geochronological constraints reveal the heterogeneous timing of eclogite- facies metamorphic re-equilibrations (Federico et al., 2005; Rubatto & Scambelluri, 2003). However, pervasive retrograde - stage tectonics and greenschist imprint (Capponi & Crispini, 2002) mask structural relationships among units acquired at high pressure conditions. As a consequence, we discuss formation of the studied mélange and the feasibility of the subduction channel mode of exhumation at larger scale, in the Voltri massif, as already invoked for the Monviso Massif of the Western Alps (Guillot et al., 2004). Capponi, G., Crispini, L. - 2002 - Eclogae Geologicae Helvetiae, v. 95, 31-42. Federico, L., Capponi, G., Crispini, L., Scambelluri, M., & Villa, I.M. - 2005 - EPSL, 240, 668-680 Federico L., Crispini L., Scambelluri M. & Capponi G. - Geology, 35 (6), 499 - 502. Gerya, T.V., Stockhert, B. & Perchuk, A.L. - 2002 - Tectonics, 21(6), 1056. Guillot, S., Schwartz, S., Hattori, K., Auzende, A.L. & Lardeaux, J.M. - 2004 - in Beltrando, M., Lister, G., Ganne, J., and Boullier, A., eds., Evolution of the western Alps: Insights from metamorphism, structural geology, tectonics and geochronology, Journal of the Virtual Explorer, Electronic Edition, ISSN 1441-8142, v. 16, Paper 3. Rubatto D., Scambelluri M. - 2003 - Contrib. Mineral. Petrol. 146 (3), 341- 355.

  10. Nonlinear geochemical dynamics and petrography: Burial dolomitization (Invited)

    NASA Astrophysics Data System (ADS)

    Merino, E.

    2010-12-01

    both the formation of self-organized syntaxial zebra veins [4,9] hosted by the replacive dolomite, and the curving of the displacive (“saddle”) dolomite crystals, precisely as observed petrographically. The model also explains why dolomitization affects only limestones and why MVT Pb and Zn ores are hosted in dolostones. [1] Merino (1984), in Nicolis & Baras, eds., Chemical Instabilities, NATO Adv. Sci. Series C 120, 305-328. [2] Merino, Wang (2001) in H.J. Krug & J.H. Kruhl, eds., Non-Equilibrium Processes in Geoscience, Self-Organization Yearbook 11, 13-45 (Dunker Humblot) [3] Ortoleva et al (1982) Amer J Sci 282, 617-643. [4] Merino et al (2006) Geologica Acta 4, 383-393. [5] Merino et al (1983) Contrib Min. Petrol. 82, 360-370. [6] Haase et al (1980) Science 209, 272-274; Wang, Merino (1992) GCActa 56, 587-596. [7] Merino, Banerjee (2008) J. Geology 116, 62-75. [8] Wang et al (2009) Nature-Geoscience 2, 781-784. [9] Merino, Canals (2010) Dynamics of dolomitization, Amer J Sci, submitted. [10] Wilson et al (2001) Amer J Sci 301, 727-752; Caspard et al (2004) Geofluids 4, 40-60; Whittaker et al (2004) in Braithwaite et al, eds., Geometry and Petrogenesis of Dolomite Hydrocarbon Reservoirs, Geol Soc London, Spec Publ 235, 99-139; Jones, Xiao (2005) Amer Assoc Petroleum Geologists bull. 89, 577-601.

  11. Espectroscopia multi-objeto e imageamento de Abell 586 com GMOS - o estado dinâmico de um aglomerado de galáxias com arcos gravitacionais

    NASA Astrophysics Data System (ADS)

    Cypriano, E. S.; Sodrã©, L., Jr.; Kneib, J.-P.; Campusano, L.

    2003-08-01

    Nesse trabalho é apresentado um estudo do conteúdo de massa do aglomerado de galáxias A586 (z = 0.171) bem como sua distribuição espacial. Isso foi feito a partir de dados de espectroscopia multi-objeto e imageamento obtidos com o instrumento GMOS acoplado ao telescópio Gemini-Norte. A massa desse aglomerado foi estudada a partir da posição dos seus arcos gravitacionais (lentes fortes), da medida estatística da distorção na forma das galáxias de fundo (lentes fracas) e através da dispersão de velocidades de uma amostra de cerca de 30 galáxias pertencentes ao aglomerado (teorema do virial). Os dois primeiros métodos não dependem do estado dinâmico do aglomerado, enquanto que o terceiro sim. Desse modo, comparando seus resultados pode-se estimar o grau de relaxamento desse sistema. Dados de raios X presentes na literatura também serão incluídos nessa análise. Nossos resultados preliminares a partir das técnicas de lentes fracas, mostram que, supondo que a distribuição de massa desse aglomerado seja a de uma esfera isotérmica, espera-se que ele apresente uma dispersão de velocidades de 1330+/-78 km s-1, em contradicao com medidas similares feitas por Dahle et al. 2002 que encontram valores tão altos quanto 1680 km s-1. Já o estudo dinâmico resultou numa dispersão de velocidades de ~950 km s-1.

  12. A Concepção de Universo entre Alunos do Ensino Médio de São Paulo e suas Fontes de Aquisição

    NASA Astrophysics Data System (ADS)

    Araújo, M. A. A.; Elias, D. C. N.; Amaral, L. H.; Araújo, M. S. T.; Voelzke, M. R.

    2006-08-01

    Nesse trabalho procurou-se identificar por meio de um questionário as concepções de Universo, de espaço e tempo que sustentam a visão de mundo de um grupo de 270 estudantes de Ensino Médio, pertencentes a três escolas de São Paulo. As questões relacionadas aos conhecimentos prévios dos estudantes permitiram constatar que há pouco conhecimento acerca dos temas investigados, destacando-se que apenas 20% dos alunos foram capazes de relacionar as semanas com as fases da lua, enquanto 28% associaram as estações do ano à inclinação do eixo de rotação da Terra e 23% tinham noções das distâncias entre objetos celestes próximos da Terra. Enquanto 56% conseguiram relacionar o Big Bang com a origem do Universo, verificou-se que 37% reconheciam ano-luz como unidade de distância e 60% concebiam o Sol como uma estrela. No que se refere às fontes de aquisição que proporcionaram esses conhecimentos, apesar de 60% dos alunos indicarem a escola como principal fonte dos conhecimentos de Ast! ronomia, verificou-se claramente que para a maioria dos alunos seus conceitos ainda são inadequados, havendo necessidade de aprimoramento da abordagem desses conteúdos, pois apesar de popular, a Astronomia ainda é veiculada de maneira pouco esclarecedora e com imprecisões. Nesse contexto, são discutidas algumas possíveis contribuições que podem ser dadas para o ensino de Astronomia pelo uso das ferramentas computacionais nas escolas.

  13. VIII Olimpíada Brasileira de Astronomia e Astronáutica

    NASA Astrophysics Data System (ADS)

    Garcia Canalle, João Batista; Villas da Rocha, Jaime Fernando; Wuensche de Souza, Carlos Alexandre; Pereira Ortiz, Roberto; Aguilera, Nuricel Villalonga; Padilha, Maria De Fátima Catta Preta; Pessoa Filho, José Bezerra; Soares Rodrigues, Ivette Maria

    2007-07-01

    Neste trabalho apresentamos as motivações pelas quais organizamos, em conjunto, pela primeira vez, a Olimpíada Brasileira de Astronomia incluindo a Astronáutica, em colaboração com a Agência Espacial Brasileira. Esta ampliação contribuiu para atrair ainda mais alunos, professores, escolas e patrocinadores para participarem desta Olimpíada. Em 2005 participaram da VIII Olimpíada Brasileira de Astronomia e Astronáutica (VIII OBA) 187.726 alunos distribuídos por 3.229 escolas, pertencentes a todos os estados brasileiros, incluindo o Distrito Federal. O crescimento em número de alunos participantes foi 52,4% maior do que em 2004. Em abril de 2005 organizamos, em Itapecerica da Serra, SP, um curso para os 50 alunos previamente selecionados e participantes da VII OBA e ao final selecionamos, dentre eles, uma equipe de 5 alunos, os quais representaram o Brasil na X Olimpíada Internacional de Astronomia, na China, em outubro de 2005. Ganhamos, pela primeira vez, uma medalha de ouro naquele evento. Em Agosto de 2005, organizamos a VIII Escola de Agosto para 50 alunos e respectivos professores, em Águas de Lindóia, SP, juntamente com a XXXI reunião anual da Sociedade Astronômica Brasileira (SAB). Em novembro de 2005 realizamos a I Jornada Espacial, em São José dos Campos, com 22 alunos e 22 professores selecionados dentre os participantes que melhores resultados obtiveram nas questões de Astronáutica da VIII OBA. Neste trabalho detalhamos os resultados da VIII OBA bem como as ações subseqüentes.

  14. Fluid Inclusion characteristics of syn-late orogenic Co-Ni-Cu-Au deposits in the Siegerland District of the Rhenish Massif, Germany

    NASA Astrophysics Data System (ADS)

    Wohlgemuth, Christoph; Hellmann, André; Meyer, Franz Michael

    2013-04-01

    studied. The fluid inclusions are located on healed intragranular trails in quartz-I grains and subordinate in quartz-II. The inclusions are 5-20 μm in size and are aqueous biphase (L+V) showing a constant L/V ratio of 4. Homogenization is always to the liquid with Th (L) = 170-250°C (202°C mean). The salinity is moderate, with a range in Tm between -8 to -3°C, corresponding to 5 - 10 mass-% NaCl eq. (8.2 mass-% mean). There is no difference between fluid inclusions investigated in quartz-I and quartz-II. Despite the common occurrence of siderite in synorogenic siderite-quartz-veins, carbonate is absent in the alteration assemblage, implying a low CO2-activity in the fluids. Isochore calculations, combined with the paleo-geothermal gradient deduced for peak metamorphic conditions (Oncken, 1991) shows that the trapping temperature of the fluid is likely in the range between 220-300°C. The study shows that Co-Ni-Cu-Au mineralization has formed at the district scale from a relative homogeneous, aqueous fluid of moderate salinity, which may have been derived from the devolatilization of the sedimentary pile in deeper crustal regions. Ahrendt, H., Hunziker, J.C. and Weber, K. (1978). Z.dt.geol.Ges.129, 229-247. Hein, U.F. (1993). Min. Mag. 57, 451-476. Hellmann, A., Wagner, T., Meyer, F.M. (2012b). Tagungsband Geologica Belgica 2012. Hellmann, A., Meyer F.M., Cormann, A., Peters, M. (2011a). Referate-Band MinPet 2011, 40. Oncken, O (1991). Annales de la Société géologique de Belgique 2, 139-159. Slack, J.F., et al. (2010). USGS Open File Report 2010-2012, 13 pp.

  15. Prograde and retrograde metamorphic processes in high-pressure subduction zone serpentinites from East Thessaly, Greece

    NASA Astrophysics Data System (ADS)

    Koutsovitis, Petros

    2016-04-01

    al 2002: Geologica Carpathica 53, 164-165; [6] Deschamps, et al 2013: Lithos 178, 96-127; [7] Hattori & Guillot, 2007: G-Cubed 8 (9); [8] Barnes et al 2014: Chemi Geol 389, 29-47; [9] Melfos et al 2009: Geoph. Res. Abst, 11.

  16. Low-grade metamorphism in the eastern Southern Alps: Distribution, conditions, timing and implications for the tectonics of the Alps and NW Dinarides

    NASA Astrophysics Data System (ADS)

    Neubauer, Franz; Heberer, Bianca; Genser, Johann; Friedl, Getrude

    2014-05-01

    main body of the Alpine orogen exposed north of the E-trending Periadriatic fault. In previous interpretations, the eastern Southalpine unit was considered to differ in many respects from Alpine units north of the Periadriatic fault including (1) no Alpine metamorphic overprint and, therefore, (2) also no Alpine ductile deformation in contrast to amphibolite- and even eclogite- grade metamorphism (ca. 100 - 85 Ma) in Austroalpine units north of the fault, and by (3) S- to SW-, Adria-directed vergency of the deformation of mostly Eocene to Neogene age in contrast to all units basically directed to the north and northwest, towards the stable European plate. The Southalpine unit is considered as back-thrust of the Middle-Late Eocene plate collision between Stable Europe and the Alpine thrust wedge (Doglioni & Bosellini, 1987). The new data from the eastern part of the Southalpine unit challenge this view and imply a steadily but slowly growing Adria-directed thrust wedge between Maastrichtian and Early Eocene times. Acknowledement: The work has been supported by the Austrian Science Fund (project no. 22,110). References Borojević Šoštarić, S. Neubauer, F., Handler, R., Palinkaš, L. A., 2012. Variscan vs. Alpine tectonothermal events in NW-Dinarides: constraints from 40Ar/39Ar dating. Geologica Carpathica, 63, 441-452. Doglioni, C., Bosellini, A., 1987. Eoalpine and mesoalpine tectonics in the Southern Alps. Geologische Rundschaus, 76, 735-754. Feijth, J., 2002. Paleozoic and Mesozoic tectonometamorphic development and geochronology of the Orobic chain (Southern Alps, Lombardy, Italy). PhD thesis, Faculty of Engineering and Applied Geosciences, Technical University of Berlin, 136 p. Ilić, A., Neubauer, F., Handler, R. (submitted). Formation of a structural dome due to transpression: The Lim unit in Central Dinarides. Journal of Structural Geology. Läufer, A.L., Frisch, W., Steinitz, G., Loeschke, J., 1997. Exhumed fault-bounded Alpine blocks along the Periadriatic

  17. Gratkorn - A new late Middle Miocene vertebrate fauna from Styria (Late Sarmatian, Austria)

    NASA Astrophysics Data System (ADS)

    Gross, M.; Böhme, M.; Prieto, J.

    2009-04-01

    still under investigation. We are especially grateful to Gudrun Daxner-Höck, Ursula Göhlich (both Natural History Museum Vienna) and Getrud Rössner (University of Munich) for their comments to the rodents, ruminants, proboscidians and bird remains. References Böhme, M., Ilg, A., Winklhofer, M. 2008. Late Miocene "washhouse" climate in Europe.- Earth and Planetary Science Letters, 275: 393-401. Gross, M., 2008. A limnic ostracod fauna from the surroundings of the Central Paratethys (Late Middle Miocene/Early Late Miocene; Styrian Basin; Austria).- Palaeogeography, Palaeoclimatology, Palaeoecology, 264/3-4: 263-276. Harzhauser, M., Gross, M. & Binder, H., 2008. Biostratigraphy of Middle Miocene (Sarmatian) wetland systems in an Eastern Alpine intramontane basin (Gratkorn Basin, Austria): the terrestrial gastropod approach.- Geologica Carpathica, 59/1: 45-58.

  18. Land to sea record of the mega-eustatic cycle including the Messinian Salinity Crisis in the Mediterranean Andalusia

    NASA Astrophysics Data System (ADS)

    Jouannic, Gwénaël.; Gorini, Christian; Jolivet, Laurent; Clauzon, Georges; Suc, Jean-Pierre; Gargani, Julien; Melinte-Dobrinescu, Mihaela Carmen; Meyer, Bertrand

    2010-05-01

    , H. (in press) - The tectonic structure of the Alboran Margin of Morocco. Revista de la Sociedad Geologica de España, 20, 3-4, 119-125. CIESM (2008) - Executive Summary. In: The Messinian Salinity Crisis from mega-deposits to microbiology - A consensus report (F. Briand, ed), CIESM Workshop Monographs, 33, 7-28. Clauzon, G., Suc, J.-P., Gautier, F., Berger, A., Loutre, M.-F. (1996) - Alternate interpretation of the Messinian salinity crisis: controversy resolve? Geology, 24, 363-366. Clauzon, G., Suc, J.-P., Popescu, S.-M., Marunteanu, M., Rubino, J.-L., Marinescu, F., Melinte, M.C. (2005) - Influence of the Mediterranean sea-level changes over the Dacic Basin (Eastern Paratethys) in the Late Neogene. The Mediterranean Lago Mare facies deciphered. Basin Research, 17, 437-462. Clauzon, G., Suc, J.-P., Melinte-Dobrinescu, M.C., Jouannic, G., Jolivet, L., Rubino, J.-L., Popescu, S.-M., Gorini, C., Bache, F., Estrada, F. (2009) - New insights from the Andalusian Sorbas and Vera basins. 13rd RCMNS Congress Naples, Acta Naturalia de L'Ateneo Parmense, 45, 1-4, 334-335. Gautier, F., Clauzon, G., Suc, J.-P., Cravatte, J., Violanti, D. (1994) - Age et durée de la crise de salinité messinienne. C. R. Acad. Sci. Paris, sér. 2, 318, 1103-1109. Hsü, K.J., Cita, M.B., Ryan, W.B.F. (1973) - The origin of the Mediterranean evaporites. In: Leg 13 (W.B.F. Ryan and K.J. Hsü, eds), Initial Report of the Deep Sea Drilling Project, 13, 1203-1231. Krijgsman, W., Hilgen, F.J., Raffi, I., Sierro, F.J., Wilson, D.S. (1999) - Chronology, causes and progression of the Messinian salinity crisis. Nature, 400, 652-655. Mauffret, A., Ammar, A, Gorini, C., Jabour, H. (2007) - The Alboran Sea (Western Mediterranean) revisited with a view from the Moroccan Margin. Terra Nova, 19, 195-203.

  19. Soil water erosion on Mediterranean vineyards. A review based on published data

    NASA Astrophysics Data System (ADS)

    Prosdocimi, Massimo; Cerdà, Artemi; Tarolli, Paolo

    2015-04-01

    soil and water management techniques to the farmers and implement soil erosion mitigation policies at appropriate spatial scales. Acknowledgements The RECARE project is funded by the European Commission FP7 program, ENV.2013.6.2-4 "Sustainable land care in Europe". References Blavet, D., De Noni, G., Le Bissonnais, Y., Leonard, M., Maillo, L., Laurent, J.Y., Asseline, J., Leprun, J. C., Arshad, M. A., Roose, E.: Effect of land use and management on the early stages of soil water erosion in French Mediterranean vineyards, Soil & Tillage Research, 106, 124-136, 2009. Brenot, J., Quiquerez, A., Petit, C., Garcia, J.-P., Davy, P.: Soil erosion rates in Burgundian vineyards, Bolletino della Società Geologica Italiana, Volume Speciale 6, 169-174, 2006. Casalí, J., Giménez, R., De Santisteban, L., Alvarez-Mozos, J., Mena, J., Del Valle de Lersundi, J.: Determination of long-term erosion rates in vineyards of Navarre (Spain) using botanical benchmarks, Catena, 78, 12-19, doi:10.1016/ j.catena.2009.02.015, 2009. Cerdà, A., Doerr, S. H.: Soil wettability, runoff and erodibility of major dry-Mediterranean land use types on calcareous soils, Hydrological Processes, 21, 2325-2336, doi: 10.1016/j.catena.2008.03.010, 2007. Ferrero, A., Usowicz, B., Lipiec, J.: Effects of tractor traffic on spatial variability of soil strength and water content in grass covered and cultivated sloping vineyard, Soil & Tillage Research, 84, 127-138, 2005. Leh, M., Bajwa, S., Chaubey, I.: Impact of land use change on erosion risk: and integrated remote sensing geographic information system and modeling methodology, Land Degradation & Development, 24, 409- 421, doi 10.1002/ldr.1137, 2013. Leonard, J., Andrieux, P.: Infiltration characteristics of soils in Mediterranean vineyards in southern France, Catena, 32, 209-223, 1998. Martinez-Casasnovas, J. A., Ramos, M. C., Benites, G.: Soil and water assessment tool soil loss simulation at the sub-basin scale in the Alt Penedès-Anoia vineyard region (NE

  20. New data on the FWF project P20018-N10: The Puez key-section in the Dolomites (Southern Alps; N-Italy)

    NASA Astrophysics Data System (ADS)

    Lukeneder, A.; Mayrhofer, S.

    2009-04-01

    . 2008. The ecological significance of solitary coral and bivalve epibionts on Lower Cretaceous (Valanginian-Aptian) ammonoids from the Italian Dolomites. Acta Geologica Polonica, 58/4, 425-436, Warschau. Lukeneder, A., Aspmair, C., 2006. Startigraphic implication of a new Lower Cretaceous ammonoid fauna from the Puez area (Valanginaian - Aptian, Dolomites, Southern Alps, Italy). Geo.Alp, 3,55-91.

  1. New integrated data (isotopes, lithology, geochemistry, ammonites etc.) from the Lower Cretaceous Puez key-section in the Dolomites (Southern Alps; N-Italy; FWF project P20018-N10)

    NASA Astrophysics Data System (ADS)

    Lukeneder, Alexander

    2010-05-01

    Cretaceous sea level changes, allow conclusions to be drawn on palaeoclimate and yield results on the biostratigraphic age coupled with more stable, exact ages resulting from the well-established techniques of magnetostratigraphy. Lukeneder A. 2008. The ecological significance of solitary coral and bivalve epibionts on Lower Cretaceous (Valanginian-Aptian) ammonoids from the Italian Dolomites. Acta Geologica Polonica, 58/4, 425-436. Lukeneder, A., Aspmair, C. 2006. Startigraphic implication of a new Lower Cretaceous ammonoid fauna from the Puez area (Valanginaian - Aptian, Dolomites, Southern Alps, Italy). Geo.Alp, 3,55-91.

  2. The San Niccolo' experimental area for studying the hydrology of coastal Mediterranean peatlands

    NASA Astrophysics Data System (ADS)

    Rossetto, Rudy; Barbagli, Alessio; Sabbatini, Tiziana; Silvestri, Nicola; Bonari, Enrico

    2015-04-01

    . & Trevisan D. (2012) - A simple model to assess nitrogen and phosphorus contamination in ungauged surface drainage networks: application to the Massaciuccoli Lake Catchment, Italy. Journal of Environmental Quality 41, 544-53. Rossetto,R., Basile, P., Cavallaro, E., Menichetti,S., Pistocchi, C., Sabbatini, T., Silvestri, N. & Bonari, E. (2010a) - Phosphorous presence in groundwater from peat oxidation: preliminary results from the Lake Massaciuccoli area (Italy). International Groundwater Symposium I.A.H.R. Valencia (Spain). Rossetto R., Basile P., Cannavò S., Pistocchi C., Sabbatini T., Silvestri N. & Bonari E. (2010b) - Surface water and groundwater monitoring and numerical modeling of the southern sector of the Massaciuccoli Lake basin (Italy). Rendiconti Online Società Geologica Italiana 11, 189-190.

  3. Gradiente radial de [Mg/Fe] em duas galáxias elípticas

    NASA Astrophysics Data System (ADS)

    Milone, A.; Capelato, H.

    2003-08-01

    Basicamente, são propostos dois cenários de evolução quí mio-dinâmico para os sistemas esferoidais: (i) o hierárquico através da fusão e/ou acresção de sub-sistemas com ou sem surtos de formação estelar, e (ii) o colapso monolí tico dissipativo com formação estelar interrompida por um vento galáctico. Ambos, dentro de certos limites, conseguem explicar os gradientes internos de metalicidade estelar presentes nas galáxias elí pticas bem como a relação observada entre a metalicidade central e a massa (Mg20 vs. log sv0). No entanto, nenhum prevê uma variação interna para a razão de abundâncias Mg/Fe que indiretamente define a escala temporal da formação estelar. Empregamos a espectroscopia óptica de fenda longa com a finalidade de recuperar as histórias de formação estelar, de enriquecimento quí mico e da dinâmica dentro de determinadas regiões das galáxias. Os espectros de média resolução (FWHM = 7,1 Å) e escala angular de 1,092 arcsec/pixel foram coletados com o telescópio 1,60m do OPD/LNA. Comparamos nossas medidas de linhas de absorção com resultados espectrofotométricos de modelos de populações estelares simples - mais especificamente os í ndices do Sistema Lick como Mg2, Mg b, < Fe > e Hb - a fim de se investigar as variações internas de [Fe/H], [Mg/Fe] e idade. Para duas galáxias elí pticas, NGC 1052 e NGC 7796, pertencentes a ambientes de baixa densidade, encontramos uma variação radial da razão Mg/Fe decrescente do centro para fora em regiões de 0,6 e 1 raio efetivo respectivamente. Discutimos alguns cenários de enriquecimento quí mico para estas duas galáxias.

  4. High School Student's Alternative Conceptions About the Phenomenon of the Formation of the Moon Phases. (Spanish Title: Concepciones Alternativas de Alumnos de Educación Media Sobre el Fenómeno de Formación de las Fases de La Luna.) Concepções Alternativas de Alunos do Ensino Médio Sobre o Fenômeno de Formação das Fases da Lua

    NASA Astrophysics Data System (ADS)

    Iachel, Gustavo; Langhi, Rodolfo; Fernandes Scalvi, Rosa Maria

    2008-07-01

    Forty students, at ages between 14 and 18 years old, from three schools in Bauru city, were questioned about their alternative conceptions concerning the phenomenon of formation of the Moon Phases. It was observed that some of the pupils confound the phenomenon of the formation of the Moon Phases with the phenomenon of the formation of the lunar eclipses, others are unaware of the reason of the phenomenon, they present incoherent alternative conceptions of the reality or incomplete conceptions. The results found here are aimed at the teachers of Elementary Education and can be used as a subsidy for future development of new pedagogical methods. Cuarenta estudiantes, con edad entre 14 y 18 años, pertenecientes a tres escuelas de la ciudad de Bauru, fueron cuestionados sobre sus concepciones alternativas acerca del fenómeno de la formación de las fases de la Luna. Fue observado que algunos alumnos confunden el fenómeno de formación de las fases de la Luna con el fenómeno de formación de los eclipses lunares, otros desconocen el motivo delfenómeno, presentan concepciones alternativas incoherentes con la realidad o bien presentan concepciones incompletas. Los resultados aquí encontrados son destinados a los profesores de la Enseñanza Básica y podrán ser usados como ayuda para el futuro desarrollo de nuevos métodos pedagógicos. Quarenta estudantes, com idades entre 14 e 18 anos, pertencentes a três escolas da cidade de Bauru, foram questionados sobre suas concepções alternativas acerca do fenômeno de formação das fases da Lua. Foi observado que alguns dos alunos confundem o fenômeno da formação das fases da Lua com o fenômeno da formação dos eclipses lunares, outros desconhecem o motivo do fenômeno, apresentam concepções alternativas incoerentes com a realidade ou então concepções incompletas. Os resultados aqui encontrados são destinados aos professores do Ensino Básico e poderão ser usados como subsídio parafuturo desenvolvimento de

  5. Abundâncias químicas de estrelas T Tauri fracas

    NASA Astrophysics Data System (ADS)

    Rojas, G. A.; Gregorio-Hetem, J.

    2003-08-01

    Apresentamos resultados do estudo de 44 estrelas pré-seqüência principal, para as quais buscamos realizar uma classificação espectroscópica e determinar parâmetros estelares e abundâncias químicas. A amostra foi escolhida da seguinte maneira : 21 objetos selecionados a partir de catálogos de objetos jovens, como o Pico dos Dias Survey e o Herbig Bell Catalogue, e 23 objetos selecionados a partir de contrapartidas ópticas de fontes de raios X detectadas pelo satélite ROSAT. Dentre 24 objetos previamente classificados como estrelas T Tauri Fracas, apenas 7 revelaram ser realmente pertencentes à essa classe, sendo os demais objetos T Tauri Clássicas ou estrelas evoluídas da pré-seqüência principal. Esse resultado demonstra que o critério mais utilizado para distinguir as T Tauri Clássicas das T Tauri Fracas, baseado na largura equivelente da emissão Ha, não é suficiente para determinar o estágio evolutivo desses objetos. Para o cálculo de parâmetros estelares e abundâncias, foram escolhidas as estrelas que apresentam características ideais para esse tipo de estudo, como ausência de velamento, baixa velocidade de rotação e espectros com razão sinal-ruído adequada. Os parâmetros estelares como temperatura efetiva e gravidade foram determinados através do equilíbrio de excitação e ionização das linhas de Ferro, e as abundâncias químicas foram calculadas utilizando o método de síntese espectral. Serão apresentados os parâmetros estelares e as abundâncias de Lítio para toda a amostra, e abundâncias de vários elementos quimicos para 7 estrelas estudadas em maior detalhe

  6. Geology and Tectonic Evolution of the Kazdaǧ Massif (NW Anatolia)

    NASA Astrophysics Data System (ADS)

    Erdoğan, B.; Akay, E.; Hasözbek, A.; Satır, M.; Siebel, W.

    2009-04-01

    and paleogeographic evolution of the southern part of the northwestern Anatolia. Geologica Romana 27, 13-80 Bingöl, E. (1971) Classification of age determination methods and application of Rb/Sr and K/Ar methods in Kazdağ. Bulletin of the Mineral Research and Exploration Institute of Turkey 14, 1-16 (in Turkish) Duru, M., Pehlivan, Ş., Şentürk, Y., Yavaş, F. ve Kar, H. (2004) New results on the lithostratigraphy of the Kazdağ Massif in northwest Turkey. Turkish Journal of Earth Sciences 13, 177-186 Okay, A.I and Monie, P. (1997) Early Mesozoic subduction in the eastern Mediterranean: Evidence from Triassic eclogite in northwest Turkey. Geology 25, 595-598 Okay, A.I and Satır, M. (2000) Coeval plutonism and metamorphism in a latest Oligocene metamorphic core complex in northwestern Turkey. Geological Magazine 137, 495-516 Okay, A.I, Siyako, M and Burkan, K.A. (1991) Geology and tectonic evolution of the Biga Peninsula, northwestern Turkey. Bulletin of the Technical University of İstanbul 44, 191-256 Okay, A.I, Monod, O and Monie, P. (2002) Triaasic blueschists and eclogites from northwestern Turkey: vestiges of the Paleo-Tethyan subduction. Lithos 64, 155-178 Okay, A.I, Satır, M., Maluski, H., Sıyako, M., Monie, P., Metzger, R., Akyüz, S., (1996) Paleo- and Neo-Tethyan events in northwestern Turkey: Geologic and geochronologic constrains. The Tectonic Evolution of Asia, 420-441 Topuz, G, Altıner, D, Satır, M, and Schwartz, W.H. (2004) Low-grade metamorphic rocks from the Pulur Complex, NE Turkey: implications for the pre-Liassic evolution of the Eastern Pontides. International Journal of Earth Science, 93, 72-91 Yaltırak C. and Okay A.İ (1994) Geology of the Paleo-Tethyan units in the north of Edremit Bay. Bulletin of the Technical University of İstanbul , 3/1, 67-79 (in Turkish)

  7. Final results on the Jurassic-Cretaceous boundary in the Gresten Klippenbelt (Austria): Macro-, micro-, nannofossils, isotopes, geochemistry, susceptibility, gamma-log and palaeomagnetic data as environmental proxies of the early Penninic Ocean history

    NASA Astrophysics Data System (ADS)

    Lukeneder, A.; Halásová, E.; Kroh, A.; Mayrhofer, S.; Pruner, P.; Reháková, D.; Schnabl, P.; Sprovieri, M.

    2009-04-01

    radioactivity of the rock and represents a direct function of its clay-mineral content. Higher radioactivity reflects a higher clay content. The gamma-log curve supports the biostratigraphic data very well. The gamma response becomes gradually weaker in the upper, undisturbed part of the section (Nu10-Nu0, Berriasian). The lower part (Nu18-Nu10, Tithonian) of the section shows the highest gamma responses. The gamma curve pattern at Nutzhof therefore shows decreasing values what corresponds well with decreasing values of susceptibility as well with the contrastingly, increasing values in carbonate content (from 50 per cent up to 95 per cent CaCo3) and increasing grey scale values (up to 250). The above reported results strongly suggest that the section mirrors a change of the depositional position of the Nutzhof section from a shallower into a deeper region, and a more stable environment on the European Helvetic shelf to slope during the Late Jurassic to Early Cretaceous time. References Hardenbol, J., Thierry, J., Farley, M. B., Jacquin, T., de Graciansky, P. C. & Vail, P. R. (1998): Mesozoic and Cenozoic sequence stratigraphy of European basins. - SEMP, Special Publications, 60, 1998. Tulsa. Henning, S., Weissert, H., Bulot, L. 1999. C-isotope stratigraphy, a calibration tool between ammonite- and magnethostratigraphy: the Valanginian-Hauterivian transition. Geologica Carpathica, 50 (1), 91-96. Kroh, A., Lukeneder, A. 2009. Crinoids from the Late Jurassic of the Nutzhof section (Lower Austria, Gresten Klippenbelt). - Annalen des Naturhistorischen Museums in Wien, Serie A, 110: 383-399. Lukeneder A. 2009. New biostratigraphic ammonite data from the Jurassic/Cretaceous boundary at Nutzhof (Gresten Klippenbelt, Lower Austria) Annalen des Naturhistorischen Museums in Wien, Serie A, 110: 313-329. Pruner, P. Schnabl, P., Lukeneder A. 2009. Preliminary results of magnetostratigraphic investigations across the Jurassic/Cretaceous boundary strata at Nutzhof, Austria. Annalen des

  8. Some deep caves in Biokovo Mountain (Croatia)

    NASA Astrophysics Data System (ADS)

    Garasic, Mladen; Garasic, Davor

    2014-05-01

    ., (2006b): "Ekspedicija Velebita 2005", Velebiten 43, pp. 2-21, SO PDS Velebit, Zagreb. Bla\\vsković, I. (1998): The two stages of structural formation of the coastal belt of the External Dinarides, Geologica Croatica, vol 51/1, Zagreb. Bockovac, Ž. (1999): Jama Amfora. Speleo'zin, 12, 7, pp. 14-15, Karlovac. Garašić, M.(1986): Hydrogeology and Morphogenesis of the Caves in Croatin Karst. Ph.D. Thesis, 1-161, University of Zagreb, Faculty of Geology, Zagreb. Garašić, M.(1989): New conception of the morphogenesis and hydrogeology of the speleological objects in karst area in Croatia (Yugoslavia). 10. International Congress of Speleology, Procceedings, vol.1, pp. 234-236, s1.8, Budapest, Hungary. Garašić, M.(1991): Morphological and Hydrogeological Classification of Speleological structures (Caves and Pits) in the Croatian Karst area. Geolo\\vski vjesnik, vol.44, pp. 289-300, Zagreb. Garašić, M.(1995): Speleogeneza u okviru hidrogeologije krša i procesa karstifikacije. 1. Hrvatski geolo\\vski kongres, Opatija, Zbornik radova, Proceedings, 177-182, Zagreb. Garašić, M.(2009a): Izvješće o speleolo\\vskom istraživanju, fotografskom i topografskom snimanju, te hidrogeolo\\vskim opservacijama u novootvorenoj jami (kaverni) u tunelu "Sveti Ilija" (servisna tunelska cijev), na stacionaži km 1+193, na trasi spojne ceste Zagvozd - Ba\\vska voda u Dalmaciji. University of Zagreb. pp. 1-39, Zagreb. Garašić, M.(2009b): Izvješće o speleolo\\vskom istraživanju, fotografskom i topografskom snimanju, te hidrogeolo\\vskim opservacijama u novootvorenoj jami (kaverni) u tunelu "Sveti Ilija" (servisna tunelska cijev), na stacionaži km 1+415, na trasi spojne ceste Zagvozd - Ba\\vska voda u Dalmaciji. University of Zagreb. pp. 1-43, Zagreb. Garašić, M.(2009c): Izvješće o speleolo\\vskom istraživanju, fotografskom i topografskom snimanju, te hidrogeolo\\vskim opservacijama u novootvorenoj jami (kaverni) u tunelu "Sveti Ilija" (servisna tunelska cijev), na stacionaži km