Upstairs-downstairs: supercontinents and large igneous provinces,are they related?     

Kent C. Condie  Anne Davaille  Richard C. Aster  Nicholas Arndt 《International Geology Review》2015,57(11-12):1341-1348

There is a correlation of global large igneous province (LIP) events with zircon age peaks at 2700, 2500, 2100, 1900, 1750, 1100, and 600 and also probably at 3450, 3000, 2000, and 300 Ma. Power spectral analyses of LIP event distributions suggest important periodicities at 250, 150, 100, 50, and 25 million years with weaker periodicities at 70–80, 45, and 18–20 Ma. The 25 million year periodicity is important only in the last 300 million years. Some LIP events are associated with granite-forming (zircon-producing) events and others are not, and LIP events at 1900 and 600 Ma correlate with peaks in craton collision frequency. LIP age peaks are associated with supercontinent rifting or breakup, but not dispersal, at 2450–2400, 2200, 1380, 1280, 800–750, and ≤200 Ma, and with supercontinent assembly at 1750 and 600 Ma. LIP peaks at 2700 and 2500 Ma and the valley between these peaks span the time of Neoarchaean supercraton assemblies. These observations are consistent with plume generation in the deep mantle operating independently of the supercontinent cycle and being controlled by lower-mantle and core-mantle boundary thermochemical dynamics. Two processes whereby plumes can impact continental assembly and breakup are (1) plumes may rise beneath supercontinents and initiate supercontinent breakup, and (2) plume ascent may increase the frequency of craton collisions and the rate of crustal growth by accelerating subduction.  相似文献   

Long-term evolution of space debris under the J_2 effect,the solar radiation pressure and the solar and lunar perturbations     

Daniel Casanova  Alexis Petit  Anne Lemaître 《Celestial Mechanics and Dynamical Astronomy》2015,123(2):223-238

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The Citizen’s Round Table process: canvassing public opinion on energy technologies to mitigate climate change   总被引：1，自引：1，他引：0  

Anne Pisarski  Peta Ashworth 《Climatic change》2013,119(2):533-546

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Coasts, water levels, and climate change: A Great Lakes perspective     

Andrew D. Gronewold  Vincent Fortin  Brent Lofgren  Anne Clites  Craig A. Stow  Frank Quinn 《Climatic change》2013,120(4):697-711

The North American Laurentian Great Lakes hold nearly 20 % of the earth’s unfrozen fresh surface water and have a length of coastline, and a coastal population, comparable to frequently-studied marine coasts. The surface water elevations of the Great Lakes, in particular, are an ideal metric for understanding impacts of climate change on large hydrologic systems, and for assessing adaption measures for absorbing those impacts. In light of the importance of the Great Lakes to the North American and global economies, the Great Lakes and the surrounding region also serve as an important benchmark for hydroclimate research, and offer an example of successful adaptive management under changing climate conditions. Here, we communicate some of the important lessons to be learned from the Great Lakes by examining how the coastline, water level, and water budget dynamics of the Great Lakes relate to other large coastal systems, along with implications for water resource management strategies and climate scenario-derived projections of future conditions. This improved understanding fills a critical gap in freshwater and marine global coastal research.  相似文献   

Ex situ cultivation of Aplysinaaerophoba close to in situ conditions: ecological, biochemical and histological aspects     

Anne Klöppel  Martin Pfannkuchen  Annika Putz  Peter Proksch  & Franz Brümmer 《Marine Ecology》2008,29(2):259-272

Sponges provide the largest number of biologically active natural products known from the marine environment and continue to be a very well studied phylum of marine fauna. The Mediterranean sponge Aplysina aerophoba accumulates brominated isoxazoline alkaloids such as Aplysinamisin-1, Aerophobin-2, Isofistularin-3 and the biotransformation product Aeroplysinin-1, which possesses, for example, antibiotic and cytotoxic properties. Until now, it is still being discussed which organisms – the sponge itself or associated microorganisms – are responsible for metabolite production. For cultivating Aplysina individuals under ex situ conditions, we surveyed relevant ecological factors in situ and controlled them in our aquarium system. We maintained A. aerophoba for more than 9 months and analysed changes of metabolite content and composition, microbial association as well as morphology in situ and ex situ under different light exposure. Although sponges showed slight reduction during maintenance, ex situ cultivation similar to in situ conditions provides a promising method to keep sponges and obtain their bioactive metabolites.  相似文献   

IGU Discussion On Geography Today,Yesterday, And Tommorrow     

Anne Buttimer  Paul Claval 《The Professional geographer》1987,39(2):221-224

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[Without Title]     

Anne Marie de Grosbois 《Environmental Geology》2006,50(6):935-939

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Early fill of the Western Irish Namurian Basin: a complex relationship between turbidites and deltas   总被引：1，自引：0，他引：1  

John D. Collinson  Ole Martinsen  Bente Bakken  Anne Kloster 《Basin Research》1991,3(4):223-242

The Western Irish Namurian Basin developed in Early Carboniferous times as a result of extension across the Shannon Lineament which probably coincides with the lapetus Suture. During the late Dinantian, axial areas of the NE-SW elongate trough became deep, whilst shallow-water limestones were deposited on the flanks. This bathymetry persisted into the Namurian when carbonate deposition ceased. In axial areas, a relatively thick mudstone succession spans earliest Namurian to Chokierian whilst on the northwestern marginal shelf, a thin, condensed Namurian mudstone sequence, in which pre-Chokierian sediments are apparently absent, rests unconformably on the Dinantian. From late Chokierian to early Kinderscoutian, the basin was filled by sand-dominated clastic sediments. Sand deposition began in the axial area with deposition of a thick turbidite sequence, the Ross Formation, which is largely equivalent to the condensed mudstone succession on the flanks. Turbidity currents flowed mainly axially towards the north-east and deposited a sequence lacking well-defined patterns of vertical bed-thickness change. Channels and slide sheets occur towards the top of the formation. The turbidite system seems to have lacked well-defined lobes and stable distributary channels. Overlying the Ross Formation, the Gull Island Formation shows a decreasing incidence of turbidite sandstones at the expense of increasing siltstones. This formation is characterized by major slides and slumps interbedded with undisturbed strata. In the flanking areas of the basin, the formation is thinner, has only a few turbidites in the sequence above the condensed mudstones and contains only one slide sheet. Overall the formation is interpreted as the deposit of a major prograding slope, the lower part representing a ramp upon which turbidites were deposited, the upper part a highly unstable muddy slope lacking any conspicuous feeder channels through which sand might have been transferred to deeper water. Progradation of the slope appears to have been increasingly from the northwestern flank of the trough which is similar to the direction deduced for the overlying deltaic Tullig cyclothem which completes the initial basin fill. Whilst several features of the succession can be explained by envisaging the whole sequence as the product of one linked depositional system, the shifting directions of palaeocurrents and palaeoslope raise problems. The switch from axial to lateral supply casts doubt on the strict application of Walther's Law to the total sequence and seems to demand large avulsive shifts of the delta system on the shelf area to the west.  相似文献   

[Without Title]     

Anne Marie de Grosbosis 《Environmental Geology》2005,49(2):339-343

Events

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Characterisation of Soot Emitted by Domestic Heating,Aircraft and Cars Using Diesel or Biodiesel   总被引：1，自引：0，他引：1  

Anne?Smekens  Ricardo?Henrique?Moreton?Godoi  Patrick?Berghmans  René?Van?GriekenEmail author 《Journal of Atmospheric Chemistry》2005,52(1):45-62

The characterisation of aggregates, like soot, firstly requires the determination of the size distribution of the primary particles. The primary particle size of combustion generated aggregates depends upon the combustion environment and the formation conditions, such as temperature, pressure and fuel-to-air ratio, among others. Since the combustion characteristics are different in the different types of burners, the characterisation of primary particles may offer the possibility to distinguish soot from different sources. In this paper, we present the signature of the primary particles and the aggregates of soot emitted by cars using diesel or biodiesel, by domestic heating, and by aircraft exhausts, which can be considered as the major sources as derived from measurements on transmission electron micrographs. The size distributions of all aggregates types with different aerodynamic diameter were log-normal and quasi-monodisperse. The size distribution of the primary particles for soot emitted by different sources showed minor differences. However, a comparison between the diameter of the primary particles and those obtained using a standard method for carbon black revealed discrepancies. The median diameter of the primary particles was combined with the median number of primary particles in an aggregate to calculate the relative particle surface area available for adsorption. In a similar way, the relative specific surface area was determined. The surface area was measured using the Brunauer-Emmett-Teller (B.E.T.) nitrogen adsorption method and the relative surface area available for adsorption was calculated.  相似文献