The 2dF galaxy redshift survey: near-infrared galaxy luminosity functions     

Shaun Cole  Peder Norberg  Carlton M. Baugh  Carlos S. Frenk  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Matthew Colless  Chris Collins  Warrick Couch  Nicholas Cross  Gavin Dalton  Roberto De Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Karl Glazebrook  Carole Jackson  Ofer Lahav  Ian Lewis  Stuart Lumsden  Steve Maddox  Darren Madgwick  John A. Peacock  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2001,326(1):255-273

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Radial velocities in the open cluster IC 2391     

Hugo Levato  Beatriz García  Carlos Loustó  Nidia Morrell 《Astrophysics and Space Science》1988,146(2):361-373

We have determined radial velocities for 31 stars in the field of the open cluster IC 2391, and derived the percentage of probable radial-velocity variables. We improved the orbit of one previously known spectroscopic binary, and confirmed the existence of two double-line binaries. We discussed with such data the membership to the cluster, the average cluster radial velocity and compared the incidence of short-period binaries among the Main-Sequence members of IC 2391 with the incidence for other clusters with similar average axial rotation of its members.Member of the Carrera del Investigador Científico del Consejo Nacional de Investigaciones Científicas y Técnicas de la República ArgentinaVisiting Astronomer, Cerro Tololo Inter-American Observatory, operated by AURA, Inc. under contract with the National Science Foundation.  相似文献   

The distribution of satellite galaxies: the great pancake     

Noam I. Libeskind  Carlos S. Frenk  Shaun Cole  John C. Helly  Adrian Jenkins  Julio F. Navarro  Chris Power 《Monthly notices of the Royal Astronomical Society》2005,363(1):146-152

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An old old friend revisited     

Carlos L. Aiken  John R. Sturgul 《Mathematical Geology》1971,3(4):381

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Ecosystem metabolism and carbon fluxes of a tidally-dominated coastal lagoon   总被引：1，自引：0，他引：1  

Rui?SantosEmail author  Jo?o?Silva  Ana?Alexandre  Nuria?Navarro  Cristina?Barrón  Carlos?M.?Duarte 《Estuaries and Coasts》2004,27(6):977-985

The metabolism and carbon flux in the western sector of the highly dynamic coastal lagoon Ria Formosa (south Portugal) were assessed to elucidate the relative importance of the contribution of the main communities, the treated sewage inputs from the adjacent city of Faro, and the exchange with the adjacent coastal waters to the ecosystem metabolism. The results depict the Ria Formosa as being a highly productive ecosystem dominated by the seagrassZostera noltii. The community dominated by the seagrassCymodocea nodosa had half of the gross production ofZ. noltii, followed by bare sediments and phytoplankton. The net contribution of seagrasses to community metabolism was negligible, as bothZ. noltii andC. nodosa showed a production: respiration ratio close to 1. Benthic microalgae emerge as the most important components of the net metabolism. The western sector of Ria Formosa was in metabolic balance during the summer when the study was done. Even though the total net ecosystem production was 7.22 Kmol C d⁻¹, the error associated with this estimate was 8.38 Kmol C d⁻¹, so ecosystem net production was not significantly different from zero. The Ria Formosa ecosystem is shallow and rapidly flushed by the tides, which force an important exchange of dissolved organic carbon (DOC) and particulate organic carbon (POC) with the adjacent coastal waters. The daily net export rate to the adjacent coastal waters, 0.98 Kmol d⁻¹, represented 7.6% of the net ecosystem production, suggesting that the bulk of the net ecosystem production accumulates within the ecosystem. The organic carbon retention in the western sector of the Ria Formosa is higher than net production, because the allochthonous carbon inputs from urban sewage enter the carbon mass balance with about 40% of the autochthonous processes, at about 1.6 Kmol d⁻¹ of DOC and 2.8 Kmol d⁻¹ of POC. The western sector of Ria Formosa has an organic carbon sink of about 46.4 tons per year. Most of this is harvested in the form of molluscs (clams, cuttlefish, etc.) and fish (sea bream, sea bass, etc.). The total carbon harvested every year in the form of bivalves is about 40 tons, rendering the Ria Formosa the most productive seafood area in Portugal.  相似文献   

Allometric laws and prediction in estuarine and coastal ecology   总被引：1，自引：0，他引：1  

Lora A. Harris  Carlos M. Duarte  Scott W. Nixon 《Estuaries and Coasts》2006,29(2):340-344

A theoretical and quantitative framework of first principles would benefit estuarine and coastal ecologists in search of predictions to enhance our understanding and management of marine resources. The Metabolic Theory of Ecology describes a possible unifying theory for ecology, including mechanistically derived equations that predict scaling exponents observed in empirical, allometric relationships from individuals to ecosystems. The controversy surrounding this theory should stimulate our exploration of its potential use in the coastal realm, where questions specific to an applied science may suggest new refinements and derivations, contributing to the overall progress of ecology.  相似文献   

Geology, geochemistry, and U–Pb geochronology of the Archean (2.74 Ga) Serra do Rabo granite stocks, Carajás Metallogenetic Province, northern Brazil     

Alex Souza Sardinha  Carlos Eduardo de Mesquita Barros  Robert Krymsky   《Journal of South American Earth Sciences》2006,20(4):327-339

The Carajás region, located in the southeastern part of the Amazon Craton, has been considered one of the most important mineral provinces in the world. The Serra do Rabo Granite (SRG) crops out near the eastern termination of the Carajás fault as two granite stocks, elongated approximately in an E–W direction, concordant with the regional structures. Leucomicrocline granite, hornblende–microcline granite, biotite–hornblende–microcline granite, hornblende syenogranite, and subordinate aplite are identified. The granites are grayish pink and coarse to medium grained and have mainly hypidiomorphic granular texture. Granophyric textures are common. The accessory minerals are ilmenite, apatite, zircon, allanite, and rare pyroxene.The SRG rocks are either massive or foliated, with a slightly anastomosed continuous S₁ foliation (E–W/subvertical) outlined by the preferred orientation of quartz, feldspars, and mafic minerals. Locally, decimeter- to meter-wide mylonite/ultramylonite bands (S_1m) occur along the E–W foliation. The S₁ foliation was developed under higher temperatures than those of the S_1m mylonite foliation. The SRG structural evolution was controlled by progressive deformation under decreasing temperature, indicative of syntectonic emplacement. The SRG also has relatively high SiO₂, K₂O, and Na₂O contents; high FeO*/(FeO*+MgO) ratios; high Zr, Ba, Nb, and Ga; and very high rare-earth element contents. The chemical signature is moderately alkaline and metaluminous, comparable to that of the A-type, A2, and ALK-3 granites. The origin of the SRG magmas may be related to the partial melting of crustal sources, such as previously metamorphosed calc-alkaline granites.The SRG crosscuts supracrustal rocks, promoting low-pressure/high-temperature metamorphism. The interaction between regional compressive stresses and the ballooning effect of the granite stocks promoted slight aureole flattening and rheological changes in the supracrustal rocks. The U–Pb zircon age of 2743±1.6 Ma is interpreted as the age of zircon crystallization, granite stock emplacement, and regional horizontal shortening. Other 2.7 Ga syntectonic alkaline granites (e.g. Estrela, Plaquê, Planalto) have been reported in the region.  相似文献   

Applying sandstone petrofacies to unravel the Upper Carboniferous evolution of the Paganzo Basin, northwest Argentina     

Laura I. Net  Carlos O. Limarino   《Journal of South American Earth Sciences》2006,22(3-4):239

A compositional study of sandstones belonging to the lower section of the Paganzo Group (Middle Carboniferous–Early Permian) in the Paganzo Basin (northwestern Argentina) helps unravel the stratigraphic and paleogeographic evolution of the basin. Three morphotectonic units constitute the complex basement of the basin: (1) to the east, the igneous–metamorphic basement of the Sierras Pampeanas and Famatina systems; (2) to the west, the Precordillera, made up of Early and Middle Paleozoic sedimentary rocks; and (3) the Upper Paleozoic volcanic arc along the western boundary with the Río Blanco Basin. On the basis of sandstone detrital modes of the Lagares, Malanzán, Loma Larga, Guandacol, Tupe, Punta del Agua, and Río del Peñón formations, seven petrofacies are distinguished: quartzofeldespathic (QF), quartzofeldespathic-metamorphic enriched (QF-Lm), quartzofeldespathic-sedimentary enriched (QF-Ls), mixed quartzolithic (QL), quartzolithic-volcanic (QLv), volcanolithic-quartzose (LvQ), and volcanolithic (Lv). The spatial and temporal distribution of these petrofacies suggest an evolutive model for the Upper Paleozoic sedimentary filling of the basin that includes three “petrosomes”: (1) the basement petrosome, a clastic wedge of arkosic composition that diachronically prograded and thinned from east to west; (2) the recycled orogen petrosome, revealing the Protoprecordillera as a positive element in the western Paganzo Basin during the Namurian; and (3) the volcanic arc petrosome, recording volcanic activity along the western margin of Gondwana during the Westphalian.  相似文献   

Tetrapods from the Upper Cretaceous (Turonian–Maastrichtian) Bauru Group of Brazil: a reappraisal     

Carlos Roberto A. Candeiro  Agustín G. Martinelli  Leonardo S. Avilla  Thomas H. Rich   《Cretaceous Research》2006,27(6):923-946

An updated, annotated list of all tetrapods from the Adamantina, Uberaba and Marília formations (Bauru Group), which constitute some of the best studied Upper Cretaceous units in Brazil, is presented. Tetrapod diversity in the Bauru Group is remarkable, including an admixture of typically austral Gondwanan taxa (e.g., abelisaurids, notosuchians) and boreal Gondwanan forms (e.g., carcharodontosaurids). Of note is the absence of Laurasian taxa in the upper portion of the Bauru Group. With the exception of some turtles, an anuran, mesoeucrocodylians and one titanosaur, most taxa from the Bauru Group are based on fragmentary and isolated bones, and as such many specimens can be identified only to a higher taxonomic level. Fishes, turtles, anurans, mesoeucrocodylians, dinosaurs, birds and mammals from the Adamantina and Marília formations resemble the latest Late Cretaceous vertebrate faunas from southern South America, except for the absence of ornithischian dinosaurs.  相似文献   

Enhancing Geo-Service Chaining through Deep Service Descriptions   总被引：2，自引：0，他引：2  

Rob Lemmens  Rolf de By  Michael Gould  reas Wytzisk  Carlos Granell  Peter van Oosterom 《Transactions in GIS》2007,11(6):849-871

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