IGU Reports: Symposium (Lisboa, Portugal, 27-29/VIII/1997)     

Josephina Gómez Mendoza 《GeoJournal》1998,44(2):176-176

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Site-Testing Results at La Palma Observatory     

A.M. Varela  C. Muñoz-Tuñón  T. Mahoney 《Astrophysics and Space Science》1998,263(1-4):373-376

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CCD Photometry of Very Young Open Clusters     

A. Marco  G. Bernabeau  J.M. Torrejón  J. Fabregat 《Astrophysics and Space Science》1998,263(1-4):299-302

We are developing a long term programme to determine abundances of peculiar stars, as a function of age, in open clusters with ages ≤ 5 × 10⁷ yr. A fundamental part will be to deduce the ages and physical properties of these clusters with higher accuracy than in previous studies. As part of this effort we present here CCD uvbyβ photometry of two open clusters, NGC 884 and NGC 869. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Methoden zur Berechnung der Verdunstung des Neusiedler Sees     

Dr. Ferenc Kozma  Dr. Erzsébeth Tóth 《Theoretical and Applied Climatology》1975,23(1-2):99-109

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Eine Modifizierte Lösung der Randwertaufgabe Der Geodätischen Gravimetrie auf der Erdoberfläche     

Peter Biró 《Studia Geophysica et Geodaetica》1965,9(2):119-123

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Variación secular geomagnética en Sudamérica y alrededores con relación a todo el Hemisferio Sur     

Leónidas Slaucitajs 《Pure and Applied Geophysics》1964,59(1):75-83

Resumen Se aplica el análisis de energía de espectro a los datos de la variación secular geomagnética para tres observatorios del Hemisferio Sur: Pilar, Amberley, Mauritius. Las figuras 2–10 indican generalmente tres tipos de picos: a) de periodos de menos de 10 años; b) del periodo aproximado de la actividad solar de 10–11 años; c) de una fluctuación de 40–60 años. Los coeficientes de la expansión esférico-armónica de la variación secular muestran también una fluctuación del último tipo.

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Summary The power spectrum analysis is applied to geomagnetic secular variation data of three southern magnetic observatories: Pilar, Amberley, Mauritius. The figures 2–10 indicate in general three types of peaks: a) of periods less than 10 years; b) of approximately solar activity cycle; c) of 40–60 years fluctuation. Also the coefficients of spherical harmonic expansion of SV show the last type fluctuation.

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The significance of giant seismites in the Plio‐Pleistocene Baza palaeo‐lake (S Spain)     

Pedro Alfaro  Luis Gibert  Massimo Moretti  Francisco J. García‐Tortosa  Carlos Sanz de Galdeano  Jesús Galindo‐Zaldívar  Ángel C. López‐Garrido 《地学学报》2010,22(3):172-179

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Climate‐driven cyclicity in an Early Cretaceous synrift lacustrine series (Aguilón sub‐basin,NE Spain)     

Ana R. Soria  Arsenio Muñoz  Carlos L. Liesa  Aránzazu Luzón  Alfonso Meléndez  M. Nieves Meléndez 《地学学报》2012,24(5):407-416

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Fission track and U–Pb in situ dating applied to detrital zircon from the Vale do Rio do Peixe Formation,Bauru Group,Brazil     

A.N.C. Dias  C.A.S. Tello  F. Chemale  M.C.T.F. de Godoy  F. Guadagnin  P.J. Iunes  C.J. Soares  A.M.A. Osório  M.P. Bruckmann 《Journal of South American Earth Sciences》2011,31(2-3):298-305

Combined methods of fission track (FTM) and U–Pb in situ zircon dating were applied to sedimentary samples from the Vale do Rio do Peixe Formation, Bauru Basin, Brazil. Detrital zircons of nine samples were determined by the FTM, and the obtained ages varied from 239 Ma–825 Ma, which can be grouped into four main populations as the 230–300 Ma, 460–490 Ma, 500–650 Ma and 696–825 Ma groups. The U–Pb data show two clear source areas: the Early Paleozoic to Neoproterozoic zircons, ranging from 445 ± 14 to 708 ± 18 Ma, and the Paleoproterozoic zircons, ranging from 1879 ± 23 to 2085 ± 27 Ma. Subordinate occurrences of Early Neoproterozoic to Mesoproterozoic zircons (836 ± 15 and 1780 ± 38 Ma) were identified. The combined information allows us to characterize Early Brazilian, Brazilian and Rhyacian material as the main source for the zircons, which are areas situated to west of the Bauru Basin (e.g., Goiás Massif) that have been incorporated into the sedimentary cycles in the Phanerozoic (mainly in the Paraná Basin). FT zircon ages reflect the main denudation processes of the South American Plate from Neoproterozoic to Early Triassic as those related to orogenic cycles of Early Brazilian, Brazilian, Famatinian/Cuyanian and Gondwanide.  相似文献   

Do paleoclimate proxies agree? A test comparing 19 late Holocene climate and sea‐ice reconstructions from Icelandic marine and lake sediments     

Yarrow Axford  Camilla S. Andresen  John T. Andrews  Simon T. Belt  Áslaug Geirsdóttir  Guillaume Massé  Gifford H. Miller  Sædís Ólafsdóttir  Lindsay L. Vare 《第四纪科学杂志》2011,26(6):645-656

Geochemical, mineralogical and biological indicators preserved in sediments are widely used to reconstruct past climate change, but proxies differ in the degree to which their utility as climate indicators has been validated via laboratory experiments, modern spatial calibrations, or down‐core comparisons with instrumental climate data. Multi‐proxy studies provide another means of evaluating interpretations of proxies. This paper presents a multi‐proxy assessment comparing 19 sub‐centennially resolved late Holocene proxy records, covering the period 300–1900 AD, from seven Icelandic marine and lacustrine core sites. We employ simple statistical comparisons between proxy reconstructions to evaluate their correlations over time and, ultimately, their utility as proxies for regional climate. Proxies examined include oxygen isotopic composition of benthic and planktonic foraminifera, abundance of the sea‐ice biomarker IP₂₅, allochthonous quartz in marine sediments (a proxy for drift ice around Iceland), marine carbonate abundance, total organic carbon concentration, chironomid assemblages, lacustrine biogenic silica and carbon/nitrogen ratios in lake sediments. Most of the examined proxy records, including temperature and sea‐ice proxies, correlate strongly with each other over multi‐centennial timescales, and thus do appear to record changes in regional climate. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献