Full-Scale Spectrum of Boundary-Layer Winds   总被引：1，自引：1，他引：0  

Xiaoli G. Larsén  Søren E. Larsen  Erik L. Petersen 《Boundary-Layer Meteorology》2016,159(2):349-371

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Subalpine fires: the roles of vegetation,climate and,ultimately, land uses     

Bérangère Leys  Christopher Carcaillet 《Climatic change》2016,135(3-4):683-697

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Can we learn from the past? Four hundred years of changes in adaptation to floods and droughts. Measuring the vulnerability in two Hispanic cities   总被引：2，自引：0，他引：2  

Salvador Gil-Guirado  José-Antonio Espín-Sánchez  María Del Rosario Prieto 《Climatic change》2016,139(2):183-200

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Nephelinite lavas at early stage of rift initiation (Hanang volcano,North Tanzanian Divergence)     

Céline Baudouin  Fleurice Parat  Carole M. M. Denis  Fredrik Mangasini 《Contributions to Mineralogy and Petrology》2016,171(7):64

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Zinc-rich clays in supergene non-sulfide zinc deposits     

F. Choulet  M. Buatier  L. Barbanson  R. Guégan  A. Ennaciri 《Mineralium Deposita》2016,51(4):467-490

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External controls on the distribution,fabrics and mineralization of modern microbial mats in a coastal hypersaline lagoon,Cayo Coco (Cuba)   总被引：1，自引：0，他引：1       下载免费PDF全文

Anthony Bouton  Emmanuelle Vennin  Aurélie Pace  Raphaël Bourillot  Christophe Dupraz  Christophe Thomazo  Arnaud Brayard  Guy Désaubliaux  Pieter T. Visscher 《Sedimentology》2016,63(4):972-1016

Active, carbonate‐mineralizing microbial mats flourish in a tropical, highly evaporative, marine‐fed lagoonal network to the south of Cayo Coco Island (Cuba). Hypersaline conditions support the development of a complex sedimentary microbial ecosystem with diverse morphologies, a variable intensity of mineralization and a potential for preservation. In this study, the role of intrinsic (i.e. microbial) and extrinsic (i.e. physicochemical) controls on microbial mat development, mineralization and preservation was investigated. The network consists of lagoons, forming in the interdune depressions of a Pleistocene aeolian substratum; they developed due to a progressive increase in sea‐level since the Holocene. The hydrological budget in the Cayo Coco lagoonal network changes from west to east, increasing the salinity. This change progressively excludes grazers and increases the saturation index of carbonate minerals, favouring the development and mineralization of microbial mats in the easternmost lagoons. Detailed mapping of the easternmost lagoon shows four zones with different flooding regimes. The microbial activity in the mats was recorded using light–dark shifts in conjunction with microelectrode O₂ and HS^? profiles. High rates of O₂ production and consumption, in addition to substantial amounts of exopolymeric substances, are indicative of a potentially strong intrinsic control on mineralization. Seasonal, climate‐driven water fluctuations are key for mat development, mineralization, morphology and distribution. Microbial mats show no mineralization in the permanently submersed zone, and moderate mineralization in zones with alternating immersion and exposure. It is suggested that mineralization is also driven by water‐level fluctuations and evaporation. Mineralized mats are laminated and consist of alternating trapping and binding of grains and microbially induced magnesium calcite and dolomite precipitation. The macrofabrics of the mats evolve from early colonizing Flat mats to complex Cerebroid or Terrace structures. The macrofabrics are influenced by the hydrodynamic regime: wind‐driven waves inducing relief terraces in windward areas and flat morphologies on the leeward side of the lagoon. Other external drivers include: (i) storm events that either promote (for example, by bioclasts covering) or prevent (for example, by causing erosion) microbial mat preservation; and (ii) subsurface degassing, through mangrove roots and desiccation cracks covered by Flat mats (i.e. forming Hemispheroids and Cerebroidal structures). These findings provide in‐depth insights into understanding fossil microbialite morphologies that formed in lagoonal settings.  相似文献   

A Criterion for Brittle Failure of Rocks Using the Theory of Critical Distances     

Jorge Castro  Sergio Cicero  César Sagaseta 《Rock Mechanics and Rock Engineering》2016,49(1):63-77

This paper presents a new analytical criterion for brittle failure of rocks and heavily over-consolidated soils. Griffith’s model of a randomly oriented defect under a biaxial stress state is used to keep the criterion simple. The Griffith’s criterion is improved because the maximum tensile strength is not evaluated at the boundary of the defect but at a certain distance from the boundary, known as half of the critical distance. This fracture criterion is known as the point method, and is part of the theory of critical distances, which is utilised in fracture mechanics. The proposed failure criterion has two parameters: the inherent tensile strength, σ ₀, and the ratio of the half-length of the initial crack/flaw to the critical distance, a/L. These parameters are difficult to measure but they may be correlated with the uniaxial compressive and tensile strengths, σ _c and σ _t. The proposed criterion is able to reproduce the common range of strength ratios for rocks and heavily overconsolidated soils (σ _c/σ _t = 3–50) and the influence of several microstructural rock properties, such as texture and porosity. Good agreement with laboratory tests reported in the literature is found for tensile and low-confining stresses.  相似文献   

Analysis of extreme rainfall in the Ebre Observatory (Spain)     

Núria Pérez-Zanón  M. Carmen Casas-Castillo  Raúl Rodríguez-Solà  Juan Carlos Peña  Anna Rius  J. Germán Solé  Ángel Redaño 《Theoretical and Applied Climatology》2016,124(3-4):935-944

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Damaging hailstorms in South Moravia,Czech Republic,in the seventeenth to twentieth centuries as derived from taxation records     

Rudolf Brázdil  Kateřina Chromá  Hubert Valášek  Lukáš Dolák  Ladislava Řezníčková 《Theoretical and Applied Climatology》2016,123(1-2):185-198

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Daily precipitation statistics in a EURO-CORDEX RCM ensemble: added value of raw and bias-corrected high-resolution simulations     

A. Casanueva  S. Kotlarski  S. Herrera  J. Fernández  J. M. Gutiérrez  F. Boberg  A. Colette  O. B. Christensen  K. Goergen  D. Jacob  K. Keuler  G. Nikulin  C. Teichmann  R. Vautard 《Climate Dynamics》2016,47(3-4):719-737

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