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Rivera L. & Kanamori H. (2005). Representations of the radiated energy in earthquakes. Geophysical journal international, 162, 148–155.
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Lande R., Engen S., Saether B.E., Filli F., Matthyssen E. & Weimerskirch H. (2002). Estimating density depence from population time series using demographic theory and life-history data. Am. Nat., 159(4), 321–337.
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Callot J.P. & Geoffroy L. (2004). Magma flow in the East Greenland dyke swarm inferred from AMS study: Magmatic growth of volcanic margin. Geophysical journal international, 159(2), 816–830.
Abstract: Volcanic passive margins (VPMs) are characterized by large volumes of melt emplaced within the lithosphere during break-up processes. Several data and a recently proposed conceptual model of volcanic margin development suggest that VPMs are fed from localized crustal zones of magma storage, underlying large polygenetic volcanoes localized above diapir-like instabilities of the asthenosphere. We investigated the magma flow pattern within the coast-parallel dyke swarm of the East Greenland VPM, which is the only outcropping VPM, over a distance of 125 km. The 44 sampled dykes are representative of the successive families of intrusions. Igneous petrofabrics are constrained by the measurements of the anisotropy of magnetic susceptibility. The magnetic fabrics are of medium to low anisotropy (P' < 1.08) and show moderately oblate ellipsoids (T > 0) . Flow-related fabrics are recorded in 75 per cent of the sampled dykes. We infer the flow directions from the imbrication geometry of the magnetic foliation planes at the dyke margins, and check the results by measuring the preferred orientation of plagioclase in thin sections cut in the magnetic principal planes. Due to probable fabric superposition, the magnetic lineation represents the zone axis for the distribution of magnetic foliation plane. We obtained 23 reliable flow directions that are predominantly horizontal and directed away from identified crustal reservoirs. This flow pattern supports the proposed model of VPM growth, and emphasizes the localized nature of the magma sources in the mantle. The entire flood basalt sequence appears to have been fed by a restricted number of crustal reservoirs and associated dyke swarms.
Programme: 290
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Pilidou, S., K.Priestley, O.Gudmundsson & E. Debayle. (2004). Upper mantle S-wave speed heterogeneity beneath the North Atlantic and the surrounding region from regional surface wave tomography. Geophysical journal international, 159, 1057–1076.
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Thébault, E.; Schott, J. J.; Mandea, M.; Hoffbeck, J. P. (2004). A new proposal for spherical cap harmonic modelling. Geophysical journal international, 159(2), 83–103.
Abstract: The geomagnetic field above the surface of the Earth in the current-free region may be expressed as the gradient of a scalar potential solving Laplace's equation. For regions with a fairly dense coverage of data at different altitudes, a regional model ought to offer a better spatial resolution of the regional field over the volume under study than a global field expanded in spherical harmonics (SH). The spherical cap harmonics analysis (SCHA) is an attractive regional modelling tool having close relationship with global SH. With the SCHA adopted so far, difficulties arise in upward continuation and in establishing a relationship between global and local Gauss coefficients. Such a relationship would be useful, for instance, for introducing prior constraint on an inverse problem dealing with the estimation of local Gauss coefficients based upon a local data set. In this paper, we show that these difficulties are overcome if the SCHA modelling is formulated as a boundary value (BV) problem in a cone bounded radially by the surface of the Earth and an upper surface suitable for satellite data, and bounded laterally in order to encompass a specific region of study. Although the example worked out here applies only to a limited class of fields, which verifies some special flux condition, the ideas behind this formalism are quite general and should offer a new way of processing data in a bounded region of space.
Keywords: magnetic field, regional modelling, spherical cap harmonic analysis
Programme: 139;905
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Artemieva, I., M. Billien, J.J. Lévêque, W. D. Mooney. (2004). Shear wave velocity, seismic attenuation, and thermal structure of the continental upper mantle. Geophysical journal international, 157, 607–628.
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Angelier F., Bost C.A., Giraudeau M., Bouteloup G., Dano S., Chastel O. (2008). Corticosterone and foraging behavior in a diving seabird: the Adélie penguin, Pygoscelis adeliae. Gen. Comp. Endocrinol., 156, 134–144.
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Cherel Y., Fontaine C., Jackson G.D., Jackson C.H., Richard P. (2009). Tissue, ontogenic and sex-related differences in ∂13C and ∂15N values of the oceanic squid Todarodes filippovae (Cephalopoda: Ommastrephidae). Mar. Biol., 156, 699–708.
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Jaeger A., Blanchard P., Richard P., Cherel Y. (2009). Using carbon and nitrogen isotopic values of body feathers to infer inter- and intra-individual variations of seabird feeding ecology during moult. Mar. Biol., 156, 1233–1240.
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VERREAULT J., VERBOVEN N., GABRIELSEN G., LETCHER R.J., CHASTEL O. (2008). Changes in prolactin in a highly organohalogen contaminated Arctic top predator seabird, the glaucous gull. Gen. Comp. Endocrinol., 156, 569–576.
Abstract: The factors influencing prolactin (PRL) variation in birds and in wildlife in general have rarely been investigated with respect to the physiological impacts of exposure to environmental contaminants. We investigated the associations between circulating baseline PRL levels and concentrations of eight persistent organohalogen contaminant (OHC) classes (i.e., major organochlorines and brominated flame retardants, and associated metabolic products) in blood (plasma) of free-ranging glaucous gulls (Larus hyperboreus), a top predator in the Norwegian Arctic, engaged in the process of incubation. We further examined whether plasma OHC concentrations were associated with the variation of PRL in glaucous gulls exposed to a standardized capture/restraint protocol. Plasma OHC concentrations in male glaucous gulls were 2-to 3-fold higher relative to females. Baseline PRL levels tended to be higher in females compared to males, although not significantly (p = 0.20). In both males and females, the 30-min capture/restraint protocol led on average to a 26% decrease in PRL levels, which resulted in a rate of PRL decrease of 0.76 ng/mL/min. The baseline PRL levels and the rate of decrease in PRL levels tended to vary negatively with plasma OHC concentrations in males, but not in females, although several of these associations did not adhere with the criterion of significance (a = 0.05). Present results suggest that in highly OHC-exposed male glaucous gulls, the control of PRL release may be affected by the direct or indirect modulating actions of OHCs and/or their metabolically derived products. We conclude that potentially OHC-mediated impact on PRL secretion in glaucous gulls (males) may be a contributing factor to the adverse effects observed on the reproductive behavior, development and population size of glaucous gulls breeding in the Norwegian Arctic.
Programme: 330
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