Origin of CO2 and carbonate veins in mantle-derived xenoliths in the Pannonian Basin

The origin and evolution of CO2 inclusions and calcite veins in peridotite xenoliths of the Pannonian Basin, Hungary, were investigated by means of petrographic investigation and stable isotope analyses. The fluid inclusions recovered in paragenetic olivine and clinopyroxene belong to distinct populations: type A (texturally early) inclusions with regular shapes (often with negative crystal forms) forming intragranular trails, type B (texturally late) inclusions defining randomly oriented trails that reach grain boundaries Type B inclusions are often associated with silicate melt (type C) inclusions Stable carbon isotope compositions in inclusion-hosted CO2 were obtained by vacuum crushing followed by conventional dual inlet as well as continuous flow mass spectrometry in order to eliminate possible lab artifacts. Olivines, clino- and orthopyroxenes of the host peridotite have oxygen isotope compositions from 5.3 to 6.0 parts per thousand (relative to V-SMOW). without any relationship with xenolith texture. Some of the xenoliths contained calcite in various forms veins and infillings in silicate globules in veins, secondary carbonate veins filling cracks and metasomatic veins with diffuse margins The former two carbonate types have delta C-13 values around -13 parts per thousand (relative to V-PDB) and low Sr contents (<05 wt %), whereas the third type,veins with high-temperature metasomatic features have a delta C-13 value of -5 0 parts per thousand and high Sr contents up to 34 wt.% In spite of the mantle-like delta C-13 value and the unusually high Sr content typical for mantle-derived carbonate, trace element compositions have proven a crustal origin. This observation supports the conclusions of earlier studies that the carbonate melt droplets found on peridotite xenoliths in the alkaline basalts represent mobilized sedimentary carbonate. The large delta C-13 range and the C-12-enrichment in the carbonates can be attributed to devolanlization of the migrating carbonate or infiltration of surficial fluids containing C-12-rich dissolved carbon Carbon isotope compositions of inclusion-hosted CO2 range from -17 8 to -4.8 parts per thousand (relative to V-PDB) with no relation to the amount of CO2 released by vacuum crushing. Low-delta C-13 values measured by stepwise heating under vacuum suggest that the carbon component is pristine and not related to surficial contamination, and that primary mantle fluids with delta C-13 values around -5 parts per thousand were at least partly preserved in the xenoliths Tectonic reworking and heating by the basaltic magma resulted in partial CO2 release and local C-13-depletion. (C) 2010 Elsevier B V All rights reserved

Produtividade de pepino para processamento no Vale do São Francisco

Com o objetivo de identificar as cultivares mais produtivas de pepino para processamento, instalaram-se dois experimentos de maio a agosto de 1997, em Petrolina, PE. O delineamento experimental utilizado foi em blocos ao acaso, com 18 tratamentos e três repetições. A parcela foi composta de quatro linhas de 3,0 m de comprimento, com espaçamento de 1,0x0,30 m. Os frutos comerciais foram classificados na categoria conserva com 6 a 12 cm, e categoria cornichon, com 4,0 a 5,5 cm de comprimento. Na categoria conserva, as cultivares Eureka (34,54 t/ha) e Francipak (33,72 t/ha) destacaram-se em termos de produtividade. As cultivares Pioneiro, Vlaspik e Wisconsin SMR 18 apresentaram os menores desempenhos (21,43 a 23,45 t/ha). Verificou-se uma variação de 30,74 a 37,79 g/fruto e 9,01 a 14,81 frutos/planta. Na categoria cornichon, destacaram-se as cultivares Vlasset e Supremo, seguidas de Vlasstar e Prêmio, com produtividades acima de 10,0 t/ha. O pior desempenho foi da cultivar Wisconsin SMR 18, cuja produção de frutos foi 5,61 t/ha. Foram obtidas variações de 6,09 a 7,27 g/fruto e 11,48 a 24,15 frutos/planta.

Estimativas de parâmetros genéticos da variedade BR 5028-São Francisco no Nordeste brasileiro

O objetivo deste trabalho foi obter estimativas dos parâmetros genéticos da variedade de milho BR 5028-São Francisco, submetida a 13 ciclos de seleção entre e dentro de progênies de meios-irmãos em diferentes municípios dos estados de Sergipe e Bahia. As estimativas da variância genética aditiva decresceram após os três primeiros ciclos de seleção, registrando-se uma redução drástica do ciclo I para o II, provocada pelo estresse de umidade. O ganho médio esperado com a seleção entre e dentro de progênies de meios-irmãos, por ciclo de seleção, nos três ciclos iniciais, foi de 10,6%. A variabilidade genética dessa variedade permaneceu a mesma nos ciclos VI e VII, quando a seleção foi praticada em um só local. Foi observado aumento dessa variabilidade a partir do ciclo VIII, permanecendo constante entre os ciclos IX e XV, quando a seleção foi praticada em mais de um local. Os ganhos médios esperado e obtido (ciclo/ano) entre os ciclos VI e XV foram de 20,0% e 4,03%, respectivamente. As magnitudes das estimativas dos parâmetros genéticos, no decorrer de sucessivos ciclos de seleção, justificam a continuidade do programa de melhoramento para aumentar a produção.

Descripción geográfica y estadística de la provincia de Santa Cruz de la Sierra / por D. Francisco de Viedma,...

Collection : Colección de obras y documentos relativos a la historia antigua y moderna de las provincias del Río de La Plata ; t. 3, 1

Euclidis elementorum libri decem priores, à Francisco Maurolyco in epitomen contracti.

Colbertinus

1.° Sereni cylindricorum libri duo : Francisco Maurolyco interprete. — 2.° Archimedis libellus de circuli dimensione : eodem Maurolyco interprete.

Colbertinus

1.° Theonis, ex traditione Pappi, datorum libri duo : interprete Francisco Maurolyco ; cum ejusdem Maurolyci additionibus. — 2.° Euclidis phaenomena, cum expositione Maurolyci.

Colbertinus

geometricarum quaestionum libri duo : authore Francisco Maurolyco, Siculo.

Colbertinus

1.° Autolyci liber de sphaera quae movetur, cum interpretatione et commentario Francisci Maurolyci. — 2.° Theodosii de habitationibus, de noctibus ac diebus libri duo, cum ejusdem Maurolyci interpretatione et notis. — 3.° Autolyci de vario ortu et occasu siderum non errantium libri duo : interprete Francisco Maurolyco.

Colbertinus

radices motuum, latera diametrorum, distantiae tabellae, cum regulis ad calculum pertinentibus et demonstrationibus : authore Francisco Maurolyco.

Colbertinus

[caractères grecs] seu transparentium libellus in tres partes divisus : authore Francisco Maurolyco.

Colbertinus

Menelaï sphaericorum libri tres : interprete Francisco Maurolyco, Siculo.

Colbertinus

Climate and sea-level variations along the northwestern Tethyan margin during the Valanginian C-isotope excursion: Mineralogical evidence from the Vocontian Basin (SE France)

A high resolution mineralogical study (bulk-rock and clay-fraction) was carried out upon the hemipelagic strata of the Angles section (Vocontian Basin, SE France) in which the Valanginian positive C-isotope excursion occurs. To investigate sea-level fluctuations and climate change respectively, a Detrital Index (DI: (phyllosilicates and quartz)/calcite) and a Weathering Index (WI: kaolinite/(illite + chlorite)) were established and compared to second-order sea-level fluctuations. In addition, the mineralogical data were compared with the High Nutrient Index (HNI, based on calcareous nannofossil taxa) data obtained by Duchamp-Alphonse et al. (2007), in order to assess the link between the hydrolysis conditions recorded on the surrounding continents and the trophic conditions inferred for the Vocontian Basin. It appears that the mineralogical distribution along the northwestern Tethyan margin is mainly influenced by sea-level changes during the Early Valanginian (Pertransiens to Stephanophorus ammonite Zones) and by climate variations from the late Early Valanginian to the base of the Hauterivian (top of the Stephanophorus to the Radiatus ammonite Zones). The sea-level fall observed in the Pertransiens ammonite Zone (Early Valanginian) is well expressed by an increase in detrital inputs (an increase in the DI) associated with a more proximal source and a shallower marine environment, whereas the sea-level rise recorded in the Stephanophorus ammonite Zone corresponds to a decrease in detrital influx (a decrease in the DI) as the source becomes more distal and the environment deeper. Interpretation of both DI and WI, indicates that the positive C-isotope excursion (top of the Stephanophorus to the Verrucosum ammonite Zones) is associated with an increase of detrital inputs under a stable, warm and humid climate, probably related to greenhouse conditions, the strongest hydrolysis conditions being reached at the maximum of the positive C-isotope excursion. From the Verrucosum ammonite Zone to the base of the Hauterivian (Radiatus ammonite Zone) climatic conditions evolved from weak hydrolysis conditions and, most likely, a cooler climate (resulting in a decrease in detrital inputs) to a seasonal climate in which more humid seasons alternated with more arid ones. The comparison of the WI to the HNI shows that the nutrification recorded al: the Angles section from the top of the Stephanophorus to the Radiatus ammonite Zones (including the positive C-isotope shift), is associated with climatic changes in the source areas. At that time, increased nutrient inputs were generally triggered by increased weathering processes in the source areas due to acceleration in the hydrological cycle under greenhouse conditions This scenario accords with the widely questioned palaeoenvironmental model proposed by Lini et al., (1992) and suggests that increasing greenhouse conditions are the main factor that drove the palaeoenvironmental changes observed in the hemipelagic realm of the Vocontian Basin, during the Valanginian positive C-isotope shift. This high-resolution mineralogical study highlights short-term climatic changes during the Valanginian, probably associated to rapid changes in the C-cycle. Coeval Massive Parana-Etendeka flood basalt eruptions may explain such rapid perturbations. (C) 2011 Elsevier B.V. All rights reserved.