93 research outputs found
Tentative chromosomal assignment of the glucose phosphate isomerase gene in cattle, sheep and goat by in situ hybridization
On the contribution of the horizontal sea-bed displacements into the tsunami generation process
The main reason for the generation of tsunamis is the deformation of the
bottom of the ocean caused by an underwater earthquake. Usually, only the
vertical bottom motion is taken into account while the horizontal co-seismic
displacements are neglected in the absence of landslides. In the present study
we propose a methodology based on the well-known Okada solution to reconstruct
in more details all components of the bottom coseismic displacements. Then, the
sea-bed motion is coupled with a three-dimensional weakly nonlinear water wave
solver which allows us to simulate a tsunami wave generation. We pay special
attention to the evolution of kinetic and potential energies of the resulting
wave while the contribution of the horizontal displacements into wave energy
balance is also quantified. Such contribution of horizontal displacements to
the tsunami generation has not been discussed before, and it is different from
the existing approaches. The methods proposed in this study are illustrated on
the July 17, 2006 Java tsunami and some more recent events.Comment: 30 pages; 14 figures. Accepted to Ocean Modelling. Other authors
papers can be downloaded at http://www.lama.univ-savoie.fr/~dutykh
The Making of the NEAM Tsunami Hazard Model 2018 (NEAMTHM18)
The NEAM Tsunami Hazard Model 2018 (NEAMTHM18) is a probabilistic hazard model for tsunamis generated by earthquakes. It covers the coastlines of the North-eastern Atlantic, the Mediterranean, and connected seas (NEAM). NEAMTHM18 was designed as a three-phase project. The first two phases were dedicated to the model development and hazard calculations, following a formalized decision-making process based on a multiple-expert protocol. The third phase was dedicated to documentation and dissemination. The hazard assessment workflow was structured in Steps and Levels. There are four Steps: Step-1) probabilistic earthquake model; Step-2) tsunami generation and modeling in deep water; Step-3) shoaling and inundation; Step-4) hazard aggregation and uncertainty quantification. Each Step includes a different number of Levels. Level-0 always describes the input data; the other Levels describe the intermediate results needed to proceed from one Step to another. Alternative datasets and models were considered in the implementation. The epistemic hazard uncertainty was quantified through an ensemble modeling technique accounting for alternative models’ weights and yielding a distribution of hazard curves represented by the mean and various percentiles. Hazard curves were calculated at 2,343 Points of Interest (POI) distributed at an average spacing of ∼20 km. Precalculated probability maps for five maximum inundation heights (MIH) and hazard intensity maps for five average return periods (ARP) were produced from hazard curves. In the entire NEAM Region, MIHs of several meters are rare but not impossible. Considering a 2% probability of exceedance in 50 years (ARP≈2,475 years), the POIs with MIH >5 m are fewer than 1% and are all in the Mediterranean on Libya, Egypt, Cyprus, and Greece coasts. In the North-East Atlantic, POIs with MIH >3 m are on the coasts of Mauritania and Gulf of Cadiz. Overall, 30% of the POIs have MIH >1 m. NEAMTHM18 results and documentation are available through the TSUMAPS-NEAM project website (http://www.tsumaps-neam.eu/), featuring an interactive web mapper. Although the NEAMTHM18 cannot substitute in-depth analyses at local scales, it represents the first action to start local and more detailed hazard and risk assessments and contributes to designing evacuation maps for tsunami early warning.publishedVersio
Detailing the impact of the Storegga Tsunami at Montrose, Scotland
The Storegga tsunami, dated in Norway to 8150250 years. Sedimentology showed that at Montrose, three tsunami waves came from the northeast or east, over-ran pre-existing marine sands and weathered igneous bedrock on the coastal plain. Incorporation of an inundation model predicts well a tsunami impacting on the Montrose Basin in terms of replicate direction and sediment size. However, under-estimation of run-up persisted requiring further consideration of palaeotopography and palaeo-near-shore bathymetry for it to agree with sedimentary evidence. Future model evolution incorporating this will be better able to inform on the hazard risk and potential impacts for future high-magnitude submarine generated tsunami events
Sedimentary evidence for a mid-Holocene iceberg-generated tsunami in a coastal lake, west Greenland
Tentative chromosomal assignment of the glucose phosphate isomerase gene in cattle, sheep and goat by <it>in situ </it>hybridization
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