Carbonaceous chondrites as analogs for the composition and alteration of Ceres          下载免费PDF全文

Harry Y. McSween Jr.  Joshua P. Emery  Andrew S. Rivkin  Michael J. Toplis  Julie C. Castillo‐Rogez  Thomas H. Prettyman  M. Cristina De Sanctis  Carle M. Pieters  Carol A. Raymond  Christopher T. Russell 《Meteoritics & planetary science》2018,53(9):1793-1804

The mineralogy and geochemistry of Ceres, as constrained by Dawn's instruments, are broadly consistent with a carbonaceous chondrite (CM/CI) bulk composition. Differences explainable by Ceres’s more advanced alteration include the formation of Mg‐rich serpentine and ammoniated clay; a greater proportion of carbonate and lesser organic matter; amounts of magnetite, sulfide, and carbon that could act as spectral darkening agents; and partial fractionation of water ice and silicates in the interior and regolith. Ceres is not spectrally unique, but is similar to a few other C‐class asteroids, which may also have suffered extensive alteration. All these bodies are among the largest carbonaceous chondrite asteroids, and they orbit in the same part of the Main Belt. Thus, the degree of alteration is apparently related to the size of the body. Although the ammonia now incorporated into clay likely condensed in the outer nebula, we cannot presently determine whether Ceres itself formed in the outer solar system and migrated inward or was assembled within the Main Belt, along with other carbonaceous chondrite bodies.  相似文献   

A new archival infrastructure for highly-structured astronomical data     

Erik Dovgan  Cristina Knapic  Massimo Sponza  Riccardo Smareglia 《Experimental Astronomy》2018,45(1):41-55

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Advances and Practices on the Research, Prevention and Control of Land Subsidence in Coastal Cities     

YAN Xuexin  YANG Tianliang  XU Yan  Luigi TOSI  Esther STOUTHAMER  Heri ANDREAS  Philip MINDERHOUD  Anirut LADAWADEE  Ramon HANSSEN  Gilles ERKENS  Pietro TEATINI  LIN Jinxin  Roberta BONì  Jarinya CHIMPALEE  HUANG Xinlei  Cristina Da LIO  Claudia MEISINA  Francesco ZUCCA 《《地质学报》英文版》2020,94(1):162-175

Land subsidence severely threatens most of the coastal plains around the world where high productive industrial and agricultural activities and urban centers are concentrated. Coastal subsidence damages infrastructures and exacerbates the effect of the sea-level rise at regional scale. Although it is a well-known process, there is still much more to be improved on the monitoring, mapping and modeling of ground movements, as well as the understanding of controlling mechanisms. The International Geoscience Programme recently approved an international project (IGCP 663) aiming to bring together worldwide researchers to share expertise on subsidence processes typically occurring in coastal areas and cities, including basic research, monitoring and observation, modelling and management. In this paper, we provide the research communities and potential stakeholders with the basic information to join the participating teams in developing this project. Specifically, major advances on coastal subsidence studies and information on well-known and new case studies of land subsidence in China, Italy, The Netherlands, Indonesia, Vietnam and Thailand are highlighted and summarized. Meanwhile, the networking, dissemination, annual meeting and field trip are briefly introduced.  相似文献   

Editorial: 50 Years of <Emphasis Type="Italic">Solar Physics</Emphasis>     

Paul Charbonneau  John Leibacher  Cristina Mandrini  Lidia van Driel-Gesztelyi  Michael S. Wheatland 《Solar physics》2016,291(12):3461-3465

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Analysing uncertainties in climate change impact assessment across sectors and scenarios     

Calum Brown  Evan Brown  Dave Murray-Rust  George Cojocaru  Cristina Savin  Mark Rounsevell 《Climatic change》2015,128(3-4):293-306

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In memory of a great mentor and good friend: Eugenio Fresi (1943–2010)     

Maria Cristina Gambi  Michele Scardi 《Marine Ecology》2011,32(2):258-260

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Spatial and temporal variability of deep-water algal assemblages in the Northwestern Mediterranean: The effects of an exceptional storm     

Laura Navarro  Enric Ballesteros  Cristina Linares  Bernat Hereu 《Estuarine, Coastal and Shelf Science》2011

There are deep-water populations of the endemic and threatened Mediterranean brown alga Cystoseira zosteroides in the Medes Islands Marine Reserve (NW Mediterranean). Here, the distribution, population structure, individual growth, mortality and recruitment rates of this species over two years are described in relation to the effects of an exceptional storm. We found a high spatial variability in the structure and dynamics of C. zosteroides populations at small geographical scales, suggesting that environmental factors acting at the population level display a key role in population size structure, mortality and recruitment. The elevated mortality rates recorded at some locations (almost 80%) is amongst the highest recorded for perennial algae as a consequence of a single storm, emphasizing the importance of episodic catastrophic events in the maintenance of these deep-water, slow-growing populations. These findings are of particular importance not only to fully understand the ecology of C. zosteroides, but also for its conservation.  相似文献   

A spatiotemporal calculus for reasoning about land-use trajectories   总被引：1，自引：0，他引：1  

Adeline Marinho Maciel  Gilberto Camara  Lubia Vinhas  Michelle Cristina Araújo Picoli  Rodrigo Anzolin Begotti  Luiz Fernando Ferreira Gomes de Assis 《International journal of geographical information science》2019,33(1):176-192

Earth observation images are a powerful source of data about changes in our planet. Given the magnitude of global environmental changes taking place, it is important that Earth Science researchers have access to spatiotemporal reasoning tools. One area of particular interest is land-use change. Using data obtained from images, researchers would like to express abstractions such as ‘land abandonment’, ‘forest regrowth’, and ‘agricultural intensification’. These abstractions are specific types of land-use trajectories, defined as multi-year paths from one land cover into another. Given this need, this paper introduces a spatiotemporal calculus for reasoning about land-use trajectories. Using Allen’s interval logic as a basis, we introduce new predicates that express cases of recurrence, conversion and evolution in land-use change. The proposed predicates are sufficient and necessary to express different kinds of land-use trajectories. Users can build expressions that describe how humans modify Earth’s terrestrial surface. In this way, scientists can better understand the environmental and economic effects of land-use change.  相似文献   

Corrigendum to “Pb,Cu and Cd distribution in five estuary systems of Marche,central Italy” [Mar. Pollut. Bull. 96 Issue 1–2, (15 July 2015) 441–449]     

Anna Annibaldi  Silvia Illuminati  Cristina Truzzi  Giulia Libani  Giuseppe Scarponi 《Marine pollution bulletin》2017,114(1):635

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The supergene origin of ruthenian hexaferrum in Ni‐laterites          下载免费PDF全文

Thomas Aiglsperger  Joaquín A. Proenza  Salvador Galí  Jordi Rius  Francisco Longo  Cristina Domènech 《地学学报》2017,29(2):106-116

For two decades, the nature of Fe‐rich, oxygen‐bearing, Ru–Os compounds found in the supergene environment has been debated. Ru–Os–Fe‐oxides and nano‐intergrowths of ruthenium with magnetite have been proposed. We applied FE‐SEM, EMPA, μ‐Raman spectroscopy and synchrotron tts‐μXRD to Ru–Os–Fe compounds recovered from Ni‐laterites from the Dominican Republic. The results demonstrate that a significant portion of Fe exists in a common structure with the Ru–Os alloy, that is, ruthenian hexaferrum. This mineral occurs both as nanoparticles and as micrometric patches within a matrix of Fe‐oxide(s). Our data suggest that supergene ruthenian hexaferrum with a (Ru_0.4(Os,Ir)_0.1Fe_0.5)_?1.0 stoichiometry represents the most advanced weathering product of primary laurite within Ni‐laterites from the Dominican Republic.  相似文献