The new Mars climate database

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U-Pb SHRIMP zircon dating of Grenvillian metamorphism in Western Sierras Pampeanas (Argentina) : correlation with the Arequipa-Antofalla craton and constraints on the extent of the Precordillera Terrane

The Sierras Pampeanas of Argentina, the largest outcrop of pre-Andean crystalline basement in southern South America, resulted from plate interactions along the proto-Andean margin of Gondwana, from as early as Mesoproterozoic to Late Paleozoic times (e.g., Ramos, 2004, and references therein). Two discrete Paleozoic orogenic belts have been recognized: the Early Cambrian Pampean belt in the eastern sierras, and the Ordovician Famatinian belt, which partially overprints it to the west (e.g., Rapela et al., 1998). In the Western Sierras Pampeanas, Mesoproterozoic igneous rocks (ca. 1.0–1.2 Ga) have been recognized in the Sierra de Pie de Palo (Fig. 1) (McDonough et al., 1993 M.R. McDonough, V.A. Ramos, C.E. Isachsen, S.A. Bowring and G.I. Vujovich, Edades preliminares de circones del basamento de la Sierra de Pie de Palo, Sierras Pampeanas occidentales de San Juán: sus implicancias para el supercontinente proterozoico de Rodinia, 12° Cong. Geol. Argentino, Actas vol. 3 (1993), pp. 340–342.McDonough et al., 1993, Pankhurst and Rapela, 1998 and Vujovich et al., 2004) that are time-coincident with the Grenvillian orogeny of eastern and northeastern North America (e.g., Rivers, 1997 and Corrievau and van Breemen, 2000). These Grenvillian-age rocks have been considered to be the easternmost exposure of basement to the Precordillera Terrane, a supposed Laurentian continental block accreted to Gondwana during the Famatinian orogeny (Thomas and Astini, 2003, and references therein). However, the boundaries of this Grenvillian belt are still poorly defined, and its alleged allochthoneity has been challenged (Galindo et al., 2004). Moreover, most of the Grenvillian ages so far determined relate to igneous protoliths, and there is no conclusive evidence for a Grenvillian orogenic belt, other than inferred from petrographic evidence alone (Casquet et al., 2001). We provide here the first evidence, based on U–Pb SHRIMP zircon dating at Sierra de Maz, for a Grenville-age granulite facies metamorphism, leading to the conclusion that a continuous mobile belt existed throughout the proto-Andean margin of Gondwana in Grenvillian times

The latest (version 4.3) Mars Climate Database

Introduction: The Mars Climate Database (MCD) is a database of meteorological fields derived from General Circulation Model (GCM) numerical simulations of the Martian atmosphere and validated using available observational data. The MCD includes complementary post-processing schemes such as high spatial resolution interpolation of environmental data and means of reconstructing the variability thereof. The GCM is developed at Laboratoire de Météorologie Dynamique du CNRS (Paris, France) [1,2] in collaboration with the Open University (UK), the Oxford University (UK) and the Instituto de Astrofisica de Andalucia (Spain) with support from the European Space Agency (ESA) and the Centre National d'Etudes Spatiales (CNES)

Towards an integrated approach for monitoring the effects of chemical contaminants in the Spanish coastal Mediterranean waters

Oral communicationIn the past twelve years, chemical monitoring surveys in Spanish Mediterranean coastal waters have developed from the use of native mussels to an integrated sampling of native and caged mussels, fish (red mullet) and sediment. In addition, the application of biological effect measurements (using biomarkers and bioassays) in the same matrices is being gradually arising. So far, biological measurements have comprised a suite of biomarkers in fish (EROD, Ala-D and AChE activities, Metallothionein content, DNA integrity and micronuclei abnormalities) and in mussels (Stress on Stress, lysosomal membrane stability, Metallothionein content, Micronuclei frequency, AChE and antioxidant enzymes) as well as the sea urchin embryotoxicity test with Paracentrotus lividus in sediment elutriates. Most of the driving forces behind these changes came from recommendations and Standard Operation Practices provided by expert organizations as MED POL, ICES, and OSPAR, and these changes have considerably increased the costs of monitoring. However, higher costs of intensive monitoring activities will allow contributing to a more realistic assessment of the quality and health status of the marine ecosystem. For this purpose quality assurance and the development of assessment criteria for the selected methods is a prerequisite. These requirements are necessary to meet national and international obligations (EU-MSFD, EU-WFD). Here, we present and discuss the integrated chemical-biological effect approach that is currently being proposed for implementation in the Spanish Mediterranean monitoring programme 2010-2012. The selected biological measurements, the assessment criteria obtained so far and quality assurance processes are discussed in terms of feasibility.The Spanish Mediterranean Biomonitoring Programs of chemical contamination (BMCW and BMIS programs) are conducted by the Instituto Español de Oceanografía (IEO) under the responsibility of the Ministry of Environment (MEDPOLIEO Project in 2006 and 2-ESMARME Project in 2010-2012)

Biomonitoring strategy to assess the effects of chemical pollution along the Iberian Mediterranean Coast: Present state and future development

oral presentationSince 2001, the Oceanographic Centre of Murcia (Spanish Institute of Oceanography, IEO) started to include selected biomarkers within the chemical pollution monitoring activities conducted along the Iberian Mediterranean coast. The main objectives of this biomonitoring programme are: (1) the determination of spatial distribution and temporal trends of chemical pollution in coastal and reference areas; (2) to seek evidence of detrimental biological effects and assess them over time. Sediment samples, feral fish (Mullus barbatus) and wild mussels (Mytilus galloprovincialis) are analysed yearly for selected pollutants (trace metals, organochlorinated compounds and polycyclic aromatic hydrocarbons) and selected biomarkers are measured in fish and/or mussels (EROD activity, metallothionein content, micronuclei frequency, genotoxic damages, acetylcholinesterase, stress on stress and lysosomal membrane stability). An integrated chemical-biological effect assessment approach is being conducted at four selected areas since 2006. Due to its geographical location, Spain contributes to both the CEMP and MEDPOL programmes and our future strategy will be focused to achieve the harmonization of criteria among different programmes and to meet the monitoring requirements in a cost-effective and cost-efficient way. The general strategy and methods of this biomonitoring programme together with some preliminary results and future development (use of caged mussels) are described and discussed.This Biomonitoring Programme was initially funded by the Spanish Institute of Oceanography, IEO (projects BIOMEJIMED I, BIOMEJIMED II and BIOMEJIMED III). Since November 2005 it is funded by Ministry of Environment (MEDPOLIEO project)

A deformed alkaline igneous rock–carbonatite complex from the Western Sierras Pampeanas, Argentina: Evidence for late Neoproterozoic opening of the Clymene Ocean?

A deformed ca. 570Ma syenite–carbonatite body is reported from a Grenville-age (1.0–1.2 Ga) terrane in the Sierra de Maz, one of theWestern Sierras Pampeanas of Argentina. This is the first recognition of such a rock assemblage in the basement of the Central Andes. The two main lithologies are coarse-grained syenite (often nepheline-bearing) and enclave-rich fine-grained foliated biotite–calcite carbonatite. Samples of carbonatite and syenite yield an imprecise whole rock Rb–Sr isochron age of 582±60Ma (MSWD= 1.8; Sri = 0.7029); SHRIMP U–Pb spot analysis of syenite zircons shows a total range of 206Pb–238Uages between 433 and 612 Ma, with a prominent peak at 560–580Ma defined by homogeneous zircon areas. Textural interpretation of the zircon data, combined with the constraint of the Rb–Sr data suggest that the carbonatite complex formed at ca. 570 Ma. Further disturbance of the U–Pb system took place at 525±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. 433 and 612 Ma, with a prominent peak at 560–580Ma defined by homogeneous zircon areas. Textural interpretation of the zircon data, combined with the constraint of the Rb–Sr data suggest that the carbonatite complex formed at ca. 570 Ma. Further disturbance of the U–Pb system took place at 525±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. Sri = 0.7029); SHRIMP U–Pb spot analysis of syenite zircons shows a total range of 206Pb–238Uages between 433 and 612 Ma, with a prominent peak at 560–580Ma defined by homogeneous zircon areas. Textural interpretation of the zircon data, combined with the constraint of the Rb–Sr data suggest that the carbonatite complex formed at ca. 570 Ma. Further disturbance of the U–Pb system took place at 525±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. 433 and 612 Ma, with a prominent peak at 560–580Ma defined by homogeneous zircon areas. Textural interpretation of the zircon data, combined with the constraint of the Rb–Sr data suggest that the carbonatite complex formed at ca. 570 Ma. Further disturbance of the U–Pb system took place at 525±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. ±60Ma (MSWD= 1.8; Sri = 0.7029); SHRIMP U–Pb spot analysis of syenite zircons shows a total range of 206Pb–238Uages between 433 and 612 Ma, with a prominent peak at 560–580Ma defined by homogeneous zircon areas. Textural interpretation of the zircon data, combined with the constraint of the Rb–Sr data suggest that the carbonatite complex formed at ca. 570 Ma. Further disturbance of the U–Pb system took place at 525±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. 433 and 612 Ma, with a prominent peak at 560–580Ma defined by homogeneous zircon areas. Textural interpretation of the zircon data, combined with the constraint of the Rb–Sr data suggest that the carbonatite complex formed at ca. 570 Ma. Further disturbance of the U–Pb system took place at 525±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. 206Pb–238Uages between 433 and 612 Ma, with a prominent peak at 560–580Ma defined by homogeneous zircon areas. Textural interpretation of the zircon data, combined with the constraint of the Rb–Sr data suggest that the carbonatite complex formed at ca. 570 Ma. Further disturbance of the U–Pb system took place at 525±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. ±7Ma (Pampean orogeny) and at ca. 430–440Ma (Famatinian orogeny) and it is concluded that the Western Sierras Pampeanas basement was joined to Gondwana during both events. Highly unradiogenic 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. 87Sr/86Sr values in calcites (0.70275–0.70305) provide a close estimate for the initial Sr isotope composition of the carbonatite magma. Sm–Nd data yield Nd570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust. 570 values of +3.3 to +4.8. The complex was probably formed during early opening of the Clymene Ocean from depleted mantle with a component from Meso/Neoproterozoic lower continental crust.Fil: Casquet, C.. Universidad Complutense de Madrid; EspañaFil: Pankhurst, R .J.. No especifíca;Fil: Galindo, C.. Universidad Complutense de Madrid; EspañaFil: Rapela, Carlos Washington. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; ArgentinaFil: Fanning, C. M.. No especifíca;Fil: Baldo, Edgardo Gaspar Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Dahlquist, Juan Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: González Casado, J. M.. Universidad Autónoma de Madrid; EspañaFil: Colombo, Fernando. Consejo N

Temporal variability of waves at the proton cyclotron frequency upstream from Mars: Implications for Mars distant hydrogen exosphere

We report on the temporal variability of the occurrence of waves at the local proton cyclotron frequency upstream from the Martian bow shock from Mars Global Surveyor observations during the first aerobraking and science phasing orbit periods. Observations at high southern latitudes during minimum-to-mean solar activity show that the wave occurrence rate is significantly higher around perihelion/ southern summer solstice than around the spring and autumn equinoxes. A similar trend is observed in the hydrogen (H) exospheric density profiles over the Martian dayside and South Pole obtained from a model including UV thermospheric heating effects. In spite of the complexity in the ion pickup and plasma wave generation and evolution processes, these results support the idea that variations in the occurrence of waves could be used to study the temporal evolution of the distant Martian H corona and its coupling with the thermosphere at altitudes currently inaccessible to direct measurements.Fil: Bertucci, Cesar. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Romanelli, Norberto Julio. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Chaufray, J. Y.. LATMOS; FranciaFil: Gomez, Daniel Osvaldo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Mazelle, C.. IRAP; FranciaFil: Delva, M.. IWF-ÖAW; AustriaFil: Modolo, R.. LATMOS; FranciaFil: González Galindo, F.. Instituto de Astrofísica de Andalucía; EspañaFil: Brain, D. A.. University of Colorado Boulder; Estados Unido