Acoustic estimation of longline tuna abundance   总被引：1，自引：1，他引：0  

Bertrand  Arnaud; Josse  Erwan 《ICES Journal of Marine Science》2000,57(4):919-926

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An application of Iatroscan thin-layer chromatography with flame ionization detection—lipid classes of microorganisms as biomarkers in the marine environment     

M. Goutx  C. Gerin  J.C. Bertrand 《Organic Geochemistry》1990,16(4-6)

Iatroscan TLC-FID combines the separatory capabilities of thin-layer chromatography (TLC) (on silica coated chromarods) with the possibility of quantitation by flame ionization detection (FID). It can be used to separate lipid extracts into classes of compounds ranging from neutral to polar products. The rapidity with which this system provides lipid class profiles from small samples makes it particularly useful in oceanographic studies where routine analyses of large numbers of samples are required. Lipid classes were analysed in 4 marine bacterial strains grown on various substrates and 10 microalgae isolated from the marine environment and grown in batch cultures. Data on lipid composition of these microorganisms were obtained and compared to literature data. Results show that ratios between classes of compounds within the different groups of microorganisms were characteristic enough to constitute a good print of bacterial or phytoplankton sources in organic matter in sea water. In a preliminary study, phospholipid classes from a bacterial strain and a microalga were separated. Results show that the determination of ratios between phospholipid classes in organic matter could represent an improvement in the utilization of lipid classes as biomarkers.  相似文献   

Correlations among the reflectances of vitrinite, chitinozoans, graptolites and scolecodonts     

Rudolf Bertrand 《Organic Geochemistry》1990,15(6)

Paleozoic marine sequences sampled in outcrops and wells of northeastern Gaspe Peninsula (Quebec Appalachians) yield kerogen composed in part of vitrinite and zooclasts (chitinozoans, scolecodonts and graptolites) on which reflectance measurements were made.The comparison between means of random measurements show that reflectance of chitinozoans is similar to that of telinite (vitrinite with a cellular texture) and that the reflectance of scolecodonts is significantly lower than that of telinite in the lower range of studied values. At higher reflectivities differences decrease but, at the end of the condensate gas zone reflectancea are not yet identical. As shown by previous studies, reflectance of graptolites is slightly less than that of telinite.Pyrobitumen reflectance is related to the lithology of the host-rock and no generalized correlation can be established between the reflectance of pyrobitumen and that of vitrinite.  相似文献   

The Perte-du-Rhône Formation,a new Cretaceous (Aptian-Cenomanian) lithostratigraphic unit in the Jura mountains (France and Switzerland)     

Antoine Pictet  Michel Delamette  Bertrand Matrion 《Swiss Journal of Geoscience》2016,109(2):221-240

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Experimental and Numerical Study of Wind and Turbulence in a Near-Field Dispersion Campaign at an Inhomogeneous Site     

Xiao Wei  Eric Dupont  Eric Gilbert  Luc Musson-Genon  Bertrand Carissimo 《Boundary-Layer Meteorology》2016,160(3):475-499

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Interactions between fish and fisher's spatial distribution and behaviour: an empirical study of the anchovy (Engraulis ringens) fishery of Peru   总被引：1，自引：0，他引：1  

Bertrand  Sophie; Diaz  Erich; Niquen  Miguel 《ICES Journal of Marine Science》2004,61(7):1127-1136

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Assessment of wind-forcing impact on a global wind-wave model using the TOPEX altimeter     

Hui Feng  Doug Vandemark  Yves Quilfen  Bertrand Chapron  Brian Beckley 《Ocean Engineering》2006,33(11-12):1431-1461

The study presents assessment of an operational wave model (Wavewatch III), focusing upon the model sensitivity to wind-forcing products. Four wind fields are used to drive the model, including the NCEP/NCAR reanalysis and three other products that assimilate various satellite wind measurements having high spatial resolution, including the QuikSCAT scatterometer. Three wave field statistics: significant wave height, mean zero-crossing wave period, and mean square slope are compared with collocated TOPEX altimeter derivatives to gauge the relative skill of differing wind-forced model runs, as well as to demonstrate an extended use of the altimeter beyond simply supplying wave height for wave model validation and assimilation. Results suggest that model output is critically sensitive to choice of the wind field product. Higher spatial resolution in the wind fields does lead to improved agreement for the higher-order wave statistics.  相似文献   

Neogene exhumation and relief evolution in the eastern Betics (SE Spain): Insights from the Sierra de Gador          下载免费PDF全文

Marianne Janowski  Nicolas Loget  Cécile Gautheron  Jocelyn Barbarand  Nicolas Bellahsen  Jean Van Den Driessche  Julien Babault  Bertrand Meyer 《地学学报》2017,29(2):91-97

The Betics are a key area to study an orogenic landscape disrupted by late‐orogenic extension. New low‐temperature thermochronology (LTT) data (AHe and AFT) coupled with geomorphic constraints in the Sierra de Gador (Alpujarride complex) are used to reconstruct the cooling history and evolution of relief during the Neogene. We document three stages: (1) a fast cooling event between 23 and 16 Ma associated with the well‐known extensive tectonic exhumation of the Alpujarride unit, (2) a period of slow cooling between 16 and 7.2 Ma related to a planation event and (3) a post‐7.2 Ma surface uplift associated with the inversion of the Alboran domain undetected by LTT. The planation event followed by this late uplift can explain the occurrence of inherited low‐relief surfaces overlain by Tortonian–Messinian platform deposits at the top of the range. Finally, we propose that the Sierra de Gador is a more transient landscape than the nearby Sierra Nevada.  相似文献   

Origin of components in Chilean thermal waters     

François Risacher  Bertrand Fritz  Arturo Hauser 《Journal of South American Earth Sciences》2011,31(1):153-170

Thermal waters of northern (18°–27°S) and southern (37°–45°S) Chile occur in two very different climatic, geologic and hydrologic environments: arid closed basins with abundant evaporites in the north; humid climate and well drained valleys in the south. The origin and behavior of the main components of the two groups of waters are examined and compared to each other. The modeling of the alteration of volcanic rocks leads to water compositions very different from those observed both in the north and south. In addition to hydrothermal alteration and deep emanations, the Cl/Br ratio reveals a major contribution of saline waters to the two groups: infiltrating brines from salt lakes in the north; seawater in the south.In the north, concentrations of Cl, Br, Na, K, Ca, SO₄, Li, B, Si result from the mixing of alteration waters with recycled brines. Hydrothermal alteration is obscured by this massive saline input, except for Mg. δ³⁴S values are consistent with an origin of sulfate from salar brines, which are themselves derived from deep Tertiary gypsum. In the south, two processes account for the composition of thermal waters: mixing of alteration waters with seawater and deep magmatic contribution. The mixing process controls the concentration of Cl, Br, Na, Alk, Si, K, Ca, Mg. Magmatic inputs are detectable for SO₄, Li and B. δ³⁴S suggests that sulfate stems from the mixing of alteration waters with either marine SO₄ in coastal waters or with deep SO₂ in inland waters. In both the north and south, the Mg concentration is drastically lowered (<1 μmol/L) by the probable formation of a chlorite-type mineral. In the south, very small amounts of seawater (<1% in volume) are sufficient to imprint a clear signature on thermal waters. Not only coastal springs are affected by seawater mixing, but also remote inland springs, as far as 150 km from the sea. Subduction of marine sediments in the accretive margin could be the source of the marine imprint in thermal waters of southern Chile. Seawater may be expelled from the subducted lithosphere and incorporated into the mantle source.  相似文献   

Impacts of Kelvin wave forcing in the Peru Humboldt Current system: Scenarios of spatial reorganizations from physics to fishers   总被引：2，自引：1，他引：1  

Sophie Bertrand  Boris Dewitte  Jorge Tam  Erich Díaz  Arnaud Bertrand   《Progress in Oceanography》2008,79(2-4):278

Because climate change challenges the sustainability of important fish populations and the fisheries they support, we need to understand how large scale climatic forcing affects the functioning of marine ecosystems. In the Humboldt Current system (HCS), a main driver of climatic variability is coastally-trapped Kelvin waves (KWs), themselves originating as oceanic equatorial KWs. Here we (i) describe the spatial reorganizations of living organisms in the Humboldt coastal system as affected by oceanic KWs forcing, (ii) quantify the strength of the interactions between the physical and biological component dynamics of the system, (iii) formulate hypotheses on the processes which drive the redistributions of the organisms, and (iv) build scenarios of space occupation in the HCS under varying KW forcing. To address these questions we explore, through bivariate lagged correlations and multivariate statistics, the relationships between time series of oceanic KW amplitude (TAO mooring data and model-resolved baroclinic modes) and coastal Peruvian oceanographic data (SST, coastal upwelled waters extent), anchoveta spatial distribution (mean distance to the coast, spatial concentration of the biomass, mean depth of the schools), and fishing fleet statistics (trip duration, searching duration, number of fishing sets and catch per trip, features of the foraging trajectory as observed by satellite vessel monitoring system). Data sets span all or part of January 1983 to September 2006. The results show that the effects of oceanic KW forcing are significant in all the components of the coastal ecosystem, from oceanography to the behaviour of the top predators – fishers. This result provides evidence for a bottom-up transfer of the behaviours and spatial stucturing through the ecosystem. We propose that contrasting scenarios develop during the passage of upwelling versus downwelling KWs. From a predictive point of view, we show that KW amplitudes observed in the mid-Pacific can be used to forecast which system state will dominate the HCS over the next 2–6 months. Such predictions should be integrated in the Peruvian adaptive fishery management.  相似文献