Analysis of vessel influence on spatial behaviour of fish schools using a multi-beam sonar and consequences for biomass estimates by echo-sounder     

Soria  Marc; Freon  Pierre; Gerlotto  Francois 《ICES Journal of Marine Science》1996,53(2):453-458

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The influence of tidal streams on the pre-spawning movements of atlantic herring, Clupea harengus L., in the St Lawrence estuary     

Lacoste  Karine N.; Munro  Jean; Castonguay  Martin; Saucier  Francois J.; Gagne  Jacques A. 《ICES Journal of Marine Science》2001,58(6):1286-1298

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The switching between zonal and blocked mid-latitude atmospheric circulation: a dynamical system perspective     

Davide Faranda  Giacomo Masato  Nicholas Moloney  Yuzuru Sato  Francois Daviaud  Bérengère Dubrulle  Pascal Yiou 《Climate Dynamics》2016,47(5-6):1587-1599

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A revised stratigraphic framework for later Cenozoic sequences in the northeastern Mediterranean region     

Cengiz Yetiş  Gilbert Kelling  Prof. Dr. Sungu L. Gökçen  Francois Baroz 《International Journal of Earth Sciences》1995,84(4):794-812

This study describes the lithostratigraphic character of mid-Cenozoic (Oligocene-Pliocene) sequences in different parts of the northeastern Mediterranean area and offers a detailed stratigraphic correlation for this region. The sequences concerned are drawn from the Camardi area (south-central Anatolia), the Adana Basin, the Misis Mountains and the Kyrenia Range (northern Cyprus) and the submerged Florence Rise (west of Cyprus). The stratigraphic relationships identified here indicate the following: (a) Following the middle Eocene (Lutetian) regression there was uplift throughout the entire region; (b) Episodes of fluvial and lacustrine deposition in intramontane settings ensued in most of this region during the late Eocene/early Miocene interval; (c) Following a regionally extensive phase of tectonic compression, major marine transgression commenced in the late Oligocene in northern Cyprus and in the early Miocene in adjacent southern Turkey, with the exception of the Ecemi§ Fault Zone where continental deposition continued; (d) These Oligo-Miocene transgressive sequences comprise a broadly diachronous complex of both shallow and deeper marine facies, including reefal carbonates, littoral clastics, basinal shales and fan-turbidites; (e) Deeper marine Miocene facies persisted longer in the Misis area and in northern Cyprus; (f) A regional regression occurred throughout most of the area during the late Serravallian to Tortonian interval and is marked by the abrupt, locally discordant appearance of extensive shallow marine, deltaic and fluvial deposits; (g) Continued regression in the Messinian led to the formation of significant evaporite deposits in the western and southern parts of the region, but localized uplift of the Misis area is attested by the initial deformation of the Neogene rocks there and the absence of Messinian sediments from this area; (h) In the Pliocene there was extensive emergence of the northern parts of the region interrupted by brief marine incursions. The present-day drainage pattern was established at this time; (i) Marine conditions persisted longer in northern Cyprus, where emergence occurred only in the latest Pliocene.  相似文献   

Geomechanics in hard rock mining: lessons from two case histories     

Francois E. Heuze 《Geotechnical and Geological Engineering》1983,1(1):3-25

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The practice of fast conditional simulations through the LU decomposition of the covariance matrix   总被引：9，自引：0，他引：9  

Francois Alabert 《Mathematical Geology》1987,19(5):369-386

The LU-matrix approach to conditional simulations allows fast generation of large numbers of realizations for a given stochastic process. Simplicity, flexibility, and quality are its main advantages. Its implementation for cases where dense grids and/or large numbers of conditioning data cause computational problems is discussed. A case study is presented.  相似文献   

Water concentrations and hydrogen isotope compositions of alkaline basalt-hosted clinopyroxene megacrysts and amphibole clinopyroxenites: the role of structural hydroxyl groups and molecular water     

István Kovács  Attila Demény  György Czuppon  Christophe Lécuyer  Francois Fourel  Qun-Ke Xia  Jia Liu  Zsanett Pintér  Edit Király  Kálmán Török  Ábel Szabó  Etienne Deloule  György Falus  Tamás Fancsik  Zoltán Zajacz  Judit Sándorné Kovács  Beatrix Udvardi 《Contributions to Mineralogy and Petrology》2016,171(5):38

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Crystallization conditions in the Upper Pollara magma chamber, Salina Island, Southern Tyrrhenian Sea   总被引：1，自引：0，他引：1  

P. Donato  H. Behrens  R. De Rosa  F. Holtz  F. Parat 《Mineralogy and Petrology》2006,86(1-2):89-108

Summary Pyroclastites erupted from the Upper Pollara magma chamber (13 ka, Salina Island, Aeolian Archipelago) resulted from mingling and mixing of rhyolitic and andesitic magmas. An experimental study has been conducted on the rhyolitic end-member to constrain the pre-eruptive conditions of the magma. In order to check for the role of mixing on the equilibrium phase assemblage, three different starting compositions, corresponding to three different mixing degrees, have been used. The crystallization experiments were conducted at two different oxygen fugacities and at variable temperature and fluid contents. The results indicate that the natural mineralogical assemblage can only be reproduced from a composition showing a certain degree of mixing. Assuming a pressure of 200 MPa (generally accepted for the Aeolian Islands), the pre-eruptive temperature of the magmas is estimated between 755 and 800 °C and the water content of the melt was higher than 4–4.5 wt.%. The Upper Pollara magma crystallized at relatively high fO₂ (ΔlogfO₂ = Ni–NiO + 1 log unit), compared to rhyolitic magmas from Lipari and Vulcano. As this difference has not been observed for the most primitive magmas the difference in fO₂ could be related to different degassing processes operating in Salina and Lipari – Vulcano magmas.  相似文献   

Late Quaternary climatic changes in southern Chile, as recorded in a diatom sequence of Lago Puyehue (40°40′ S)     

Mieke Sterken  Elie Verleyen  Koen Sabbe  Griet Terryn  Francois Charlet  Sébastien Bertrand  Xavier Boës  Nathalie Fagel  Marc De Batist  Wim Vyverman 《Journal of Paleolimnology》2008,39(2):219-235

A late Quaternary diatom stratigraphy of Lago Puyehue (40°40′ S, 72°28′ W) was examined in order to infer past limnological and climatic changes in the South-Chilean Lake District. The diatom assemblages were well preserved in a 1,122 cm long, ¹⁴C-dated sediment core spanning the last 17,900 years, and were in support of an early deglaciation of Lago Puyehue. The presence of a short cold spell in South Chile, equivalent to the Younger Dryas event in the Northern Hemisphere, the Antarctic Cold Reversal in Antarctica, or the Huelmo-Mascardi event in southern South America, was not clearly evidenced in the diatom data, although some climate instability may have occurred between 13,400 and 11,700 cal. yr. BP, and a relatively long period (between 16,850 and 12,810 cal. yr. BP) with low absolute abundances and biovolumes could be tentatively interpreted as a period of low rainfall and/or temperatures. An increase in the moisture supply to the lake was tentatively inferred at 12,810 cal. yr. BP. After 9,550 cal. yr. BP, inferred stronger and longer persisting summer stratification, may have been the result of the higher temperatures associated with an early-Holocene thermal optimum. The mid-Holocene appeared to be characterized by a decrease in precipitation, culminating around 5,000 cal. yr. BP, and rising again after 3,000 cal. yr. BP, likely associated with a previously documented lowered frequency and amplitude of El Niño events. An increase in precipitation during the late Holocene (3,000 cal. yr. BP–present) might have marked subsequent increased frequency of El Niño occurrences, leading to drier summers and slightly moister winters in the area.  相似文献   

A Bayesian analysis of Generalized Pareto Distribution of runoff minima   总被引：1，自引：0，他引：1       下载免费PDF全文

Youcun Liu  Miaojie Lu  Xueli Huo  Yonghong Hao  Hongkai Gao  Yan Liu  Yonghui Fan  Yuhuan Cui  Francois Metivier 《水文研究》2016,30(3):424-432

Global climate change models have predicted the intensification of extreme events, and these predictions are already occurring. For disaster management and adaptation of extreme events, it is essential to improve the accuracy of extreme value statistical models. In this study, Bayes' Theorem is introduced to estimate parameters in Generalized Pareto Distribution (GPD), and then the GPD is applied to simulate the distribution of minimum monthly runoff during dry periods in mountain areas of the Ürümqi River, Northwest China. Bayes' Theorem treats parameters as random variables and provides a robust way to convert the prior distribution of parameters into a posterior distribution. Statistical inferences based on posterior distribution can provide a more comprehensive representation of the parameters. An improved Markov Chain Monte Carlo (MCMC) method, which can solve high‐dimensional integral computation in the Bayes equation, is used to generate parameter simulations from the posterior distribution. Model diagnosis plots are made to guarantee the fitted GPD is appropriate. Then based on the GPD with Bayesian parameter estimates, monthly runoff minima corresponding to different return periods can be calculated. The results show that the improved MCMC method is able to make Markov chains converge faster. The monthly runoff minima corresponding to 10a, 25a, 50a and 100a return periods are 0.60 m³/s, 0.44 m³/s, 0.32 m³/s and 0.20 m³/s respectively. The lower boundary of 95% confidence interval of 100a return level is below zero, which implies that the Ürümqi River is likely to cease to flow when 100a return level appears in dry periods. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献