A method for combining the asymptotic operator designed by Beylkin (Born migration operator) for the solution of linearized inverse problems with full waveform inversion is presented. This operator is used to modify the standard L2 norm that measures the distance between synthetic and observed data. The modified misfit function measures the discrepancy of the synthetic and observed data after t…

Recent evidence suggests that a portion of the Canary plume travelled northeastwards below the lithosphere of the Atlas Mountains in North Africa towards the Alboran domain and was captured ∼10 Ma ago by the Gibraltar subduction system in the Western Mediterranean. The capture would have been associated with the mantle return flow induced by the west ward retreating slab that would have …

Several dinoflagellate species in the genus Blastodinium are gut parasites of marine planktonic copepods. However, there is only limited information on the occurrence and infection frequencies of Blastodinium spp. in the field and almost no information on the functional impact on their hosts. We report upon the effects of Blastodinium sp. infection on Calanus finmarchicus from the northeastern …

Measurements of seismic anisotropy are commonly used to constrain deformation in the upper mantle. Observations of anisotropy at mid-mantle depths are, however, relatively sparse. In this study we probe the anisotropic structure of the mid-mantle (transition zone and uppermost lower mantle) beneath the Japan, Izu-Bonin, and South America subduction systems. We present source-side shear wave spl…

Mating in many copepod species is not random; moreover, individuals have preferences for certain qualities in their mates. This study tested whether female mating status (virgin versus mated) affects mate choice in males in the copepod species Acartia tonsa and Acartia hudsonica, both in laboratory and field populations. In addition, the costs and benefits associated with mating twice versus on…

The PP precursors are seismic waves that form from underside reflections of P waves off discontinuities in the upper mantle transition zone (MTZ). These seismic phases are used to map discontinuity topography, sharpness, and impedance contrasts; the resulting structural variations are then often interpreted as evidence for temperature and/or mineralogy variations within the mantle. The PP precu…

One of the main challenges in contemporary biological oceanography is to understand the factors that drive the spatial heterogeneity of pelagic organisms. Our study was performed at 10-m depth intervals within the upper 50 m of the ocean, at two different localities on the West Spitsbergen Shelf in the summers of 2009 and 2010. The fine-scale patterns in vertical zooplankton distribution were …

Seismic full waveform inversion (FWI) has been applied to simple elastic problems with certain symmetries, such as isotropic, transverse isotropic or vertical transversely isotropic media. In this study, the FWI concept is extended to the most general anisotropic case with 21 independent elastic material parameters and no symmetry plane (triclinic). Beside a short description of the 3-D finite…

To test the paradigm that large-bodied zooplankton species dominate in fishless lakes, we evaluated crustacean zooplankton composition of 53 fishless boreal lakes across a broad geographic scale (north-west Saskatchewan, Canada) in relation to contemporary environmental factors. Lake productivity, acid–base status and intensity of invertebrate predation were the three major environmental filt…

In our paper published earlier we discussed forecasts of earthquake focal mechanism and ways to test the forecast efficiency. Several verification methods were proposed, but they were based on ad hoc, empirical assumptions, thus their performance is questionable. We apply a conventional likelihood method to measure the skill of earthquake focal mechanism orientation forecasts. The advantage of…