Archive Institutionnelle de l'Ifremer
Ifremer

Nouveaux documents

Ref.° 1-30 / 30 1 2 3

The krlging technique Is now employed ln more and more fields: mlnlng (Journel. 1977), hydrology (Delhomme, 197B; Shamsi et al" 1988; Dingman et al" 1988), fishery (Conan, 1989) and ecology (Robertson, 1987; Schotzko and O'Keeffe, 1989, 1990). Recent developments of the mathematlcal theory tend to extend the number of applications where Il may be used. Baslcally defined for the case of a statlonary spatial process, It now encompasses more general processes assuming less and less strong [...]
1991.   Rapport de contrat
In oyster production area the determination of the stock, estimation of mortality and growth rates are determinant for knowledge of the fishery. Growth models can be used to predict the time to reach marketable size (76 mm in Chesapeake Bay). They are also important in term of management, when they can predict the future value of the stock (Askew, 1978). Oyster growth models can be built by analysing growth of natural oysters but absolute age is orten unknown. Many authors report growth data in [...]
1991.   Rapport de contrat
Prou Jean, Heral Maurice, Goulletquer Philippe, Forget Maïté, Bougrier Serge, Razet Daniel
The project of cultivation of oyster has been designed to evaluate the growth rate, the mortality, the reproductive effort, production and biochemical composition of the oyster function of the density and the depth. This plan was intended: - to build model of growth rate, - to demonstrate the action of the different parameters on growth rate (temperature, food effect...), - to evaluate the density effect to see if the available food could be a limiting factor, - to estimate the effect of the [...]
1991.   Rapport de contrat
Daoud Mohamed A., Le Gall Bernard, Maury Rene, Rolet Joel, Huchon Philippe, Guillou Herve
The Tadjoura rift forms the westernmost edge of the westerly propagating Sheba ridge, between Arabia and Somalia, as it enters into the Afar depression. From structural and remote sensing data sets, the Tadjoura rift is interpreted as an asymmetrical south facing half-graben, about 40 km wide, dominated by a large boundary fault zone to the north. It is partially filled up by the 1-3 Myr old Gulf Basalts which onlapped the older Somali Basalts along its shallower southern flexural margin. The [...]
2011-01.   Tectonics
Watremez Louise, Leroy Sylvie, Rouzo Stephane, D'Acremont E., Unternehr P., Ebinger C., Lucazeau F., Al-Lazki A.
P>The wide-angle seismic (WAS) and gravity data of the Encens survey allow us to determine the deep crustal structure of the north-eastern Gulf of Aden non-volcanic passive margin. The Gulf of Aden is a young oceanic basin that began to open at least 17.6 Ma ago. Its current geometry shows first- and second-order segmentation: our study focusses on the Ashawq-Salalah second-order segment, between Alula-Fartak and Socotra-Hadbeen fracture zones. Modelling of the WAS and gravity data (three [...]
2011-02.   Geophysical Journal International
Ioualalen Mansour, Ratzov G., Collot Jean-Yves, Sanclemente E.
P>Shelf promontories exhibit very specific bathymetric features with regards to tsunamis. Because of their submerged cape morphology, a potential tsunami generated seawards of the promontory will exhibit a specific mode of propagation and coastal impact. To identify this peculiar tsunami signature, the Atacames Promontory, Ecuador, was chosen as a case study (another example is the shelf of the Nile delta, Egypt). The area is tectonically very active, hosts earthquakes among the most powerful [...]
2011-02.   Geophysical Journal International
Lebas E., Le Friant A., Boudon G., Watt S. F. L., Talling P. J., Feuillet Nathalie, Deplus Christine, Berndt C., Vardy M. E.
New high-resolution multichannel seismic data (GWADASEIS-2009 and JC45/46-2010 cruises; 72 and 60 channels, respectively) combined with previous data (AGUADOMAR-1999 and CARAVAL-2002; 6 and 24 channels, respectively) allow a detailed investigation of mass-wasting processes around the volcanic island of Montserrat in the Lesser Antilles. Seven submarine deposits have sources on the flanks of Montserrat, while three are related to the nearby Kahouanne submarine volcanoes. The most voluminous [...]
2011-05.   Geochemistry Geophysics Geosystems
Feuillet Nathalie, Beauducel F., Jacques E., Tapponnier P., Delouis B., Bazin S., Vallee M., King G. C. P.
On November 21, 2004, a magnitude 6.3 earthquake occurred offshore, 10 km south of Les Saintes archipelago in Guadeloupe (French West Indies). There were more than 30000 aftershocks recorded in the following two years, most of them at shallow depth near the islands of the archipelago. The main shock and its main aftershock of February 14, 2005 (M-w = 5.8) ruptured a NE-dipping normal fault (Roseau fault), mapped and identified as active from high-resolution bathymetric data a few years before. [...]
2011-10.   Journal Of Geophysical Research-solid Earth
Despres Agnes, Reverdin Gilles, D'Ovidio Francesco
A 12-yearlong thermosalinograph data set from ships of opportunity was used to make an extensive study of meso-scale surface fronts in the western part of the North Atlantic subpolar gyre from 1997 to 2009. Fronts are identified on a sea-surface-salinity/sea surface temperature gradient criterion with a typical width of 20 to 60 km. The seasonal hydrographic properties of fronts are investigated. We find that, whereas salinity jumps across fronts are close to the larger scale variations, the [...]
2011-10.   Journal Of Geophysical Research-oceans
Feuillet Nathalie, Beauducel Francois, Tapponnier Paul
The oblique convergence between North American and Caribbean plates is accommodated in a bookshelf faulting manner by active, oblique-normal faults in the northern part of the Lesser Antilles arc. In the last 20 years, two M > 6 earthquakes occurred along a large, arc parallel, en echelon fault system, the 16 March 1985 in Redonda and 21 November 2004 in Les Saintes. A better understanding of active faulting in this region permit us to review the location and magnitude of historical earthquakes [...]
2011-10.   Journal Of Geophysical Research-solid Earth
1 2 3