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Abstract. The final aim of the present work is to propose a NTHMP-benchmarked numerical tool for landslide-generated tsunami hazard assessment. To achieve this, the novel Multilayer-HySEA model is validated using laboratory experiment data for landslide-generated tsunamis. In particular, this second part of the work deals with granular slides, while the first part, in a companion paper, considers rigid slides. The experimental data used have been proposed by the US National Tsunami Hazard and Mitigation Program (NTHMP) and were established for the NTHMP Landslide Benchmark Workshop, held in January 2017 at Galveston (Texas). Three of the seven benchmark problems proposed in that workshop dealt with tsunamis
generated by rigid slides and are collected in the companion paper
(Macías et al., 2021). Another three benchmarks considered tsunamis generated by granular slides. They are the subject of the present study. The seventh benchmark problem proposed the field case of Port Valdez, Alaska, 1964 and can be found in Macías et al. (2017). In order to reproduce the laboratory experiments dealing with granular slides, two models need to be coupled: one for the granular slide and a second one for the water dynamics. The coupled model used consists of a new and efficient hybrid finite-volume–finite-difference implementation on GPU architectures of a
non-hydrostatic multilayer model coupled with a Savage–Hutter model. To introduce the multilayer model more fluidly, we first present the equations of the one-layer model, Landslide-HySEA, with both strong and weak couplings between the fluid layer and the granular slide. Then, a brief description of the multilayer model equations and the numerical
scheme used is included. The dispersive properties of the multilayer model can be found in the companion paper. Then, results for the three NTHMP benchmark problems dealing with tsunamis generated by granular slides are presented with a description of each benchmark problem.

18 pages, 10 figures, supporting information https://doi.org/10.1029/2021JB022328.-- Data Availability Statement: The results of the simulations through each fault domain, scripts needed to build the unstructured mesh, and the files containing the frictional setup can be found here: https://figshare.com/projects/Dynamic_rupture_simulation_results_from_Prada_et_al_preprint_https_doi_org_10_1002_essoar_10507023_1_/120540.-- This is a contribution of the Barcelona Center for Subsurface Imaging that is a Grup de Recerca de la Generalitat de Catalunya (2017 SGR 1662) ; Megathrust earthquakes are strongly influenced by the elastic properties of rocks surrounding the fault. In contrast to friction, these properties can be derived in situ from geophysical measurements along the seismogenic zone. However, they are often overestimated in numerical simulations, particularly in the shallow megathrust. Here we explore the influence that realistic depth-varying upper-plate elastic properties along the megathrust have on earthquake rupture dynamics and tsunamigenesis using 3D dynamic rupture and tsunami simulations. We compare results from three subduction zone scenarios with homogeneous and heterogeneous elastic media, and bimaterial fault. Elastic properties in the heterogeneous model follow a realistic depth-distribution derived from controlled-source tomography models of subduction zones. We assume the same friction properties for all scenarios. Simulations in the heterogeneous and homogeneous models show that rigidity depth variations explain the depth-varying behavior of slip, slip rate, frequency content, and rupture time. The depth-varying behavior of slip, frequency content, and rupture duration quantitatively agree with previous predictions based on worldwide data compilations, explaining the main depth-dependent traits of tsunami earthquakes and large shallow megathrust earthquakes. Large slip, slow rupture and slip rate amplification in bimaterial simulations are largely controlled by elastic rock properties of the most compliant side of the fault, which in subduction zones is the upper plate. Large shallow slip and trenchward increasing upper-plate compliance of the heterogeneous model lead to the largest co-seismic seafloor deformation and tsunami amplitude. This highlights the importance of considering realistic upper-plate rigidity variations to properly assess the tsunamigenic potential of megathrust earthquakes ; M. Prada is funded by the Beatriu de Pinós postdoctoral programme of the Government of Catalonia's Secretariat for Universities and Research of the Ministry of Economy and Knowledge (Ref # 2017BP00170). Jean-Paul Ampuero is supported by the Investments in the Future project UCAJEDI (ANR-15-IDEX-01) managed by the French National Research Agency (ANR). First author and ICM have had funding support of the "Severo Ochoa Centre of Excellence" accreditation (CEX2019-000928-S) of the Spanish Research Agency (AEI). [.] Tsunami-HySEA code development is supported by the Spanish Government-FEDER funded project MEGAFLOW (RTI2018-096064-B-C21) ; Peer reviewed

El presente artículo muestra los resultados de la investigación desarrollada en torno al aporte socioeconómico de la producción de trucha en el Encano (Pasto) y tiene como objetivo general, realizar un diagnóstico del estado actual, tendencias y desafíos económicos asociados al proceso de generación de valor agregado a partir de los residuos de la producción de trucha en dicho territorio, teniendo en cuenta el enfoque teórico del desarrollo económico local y la sostenibilidad del medio ambiente. El estudio es de tipo descriptivo, analítico e interpretativo. Metodológicamente se realizó una revisión de variables cuantitativas y cualitativas que permitieron determinar el aporte socioeconómico de la producción truchícola en la región, a partir de la aplicación de entrevistas semiestructuradas a los diferentes actores relacionados con la actividad. Los resultados arrojan que el potencial aprovechamiento de los residuos de esta especie, con el fin de obtener concentrado alimenticio de diferentes grados de hidrolisis de manera técnico-científico a escala piloto, permitiría avanzar en la superación de brechas tecnológicas, productivas y ambientales asociadas a la actividad, pero se requiere coordinar y articular las acciones de los distintos actores sociales involucrados, en torno a la formación de capacidades técnicas y funcionales, transferencia de tecnología e infraestructura.

9 pages, 4 figures, 4 supplementary videos, supplementary information https://doi.org/10.1038/s41598-021-95729-6 ; Tsunamis are triggered by sudden seafloor displacements, and usually originate from seismic activity at faults. Nevertheless, strike-slip faults are usually disregarded as major triggers, as they are thought to be capable of generating only moderate seafloor deformation; accordingly, the tsunamigenic potential of the vertical throw at the tips of strike-slip faults is not thought to be significant. We found the active dextral NW–SE Averroes Fault in the central Alboran Sea (westernmost Mediterranean) has a historical vertical throw of up to 5.4 m at its northwestern tip corresponding to an earthquake of Mw 7.0. We modelled the tsunamigenic potential of this seafloor deformation by Tsunami-HySEA software using the Coulomb 3.3 code. Waves propagating on two main branches reach highly populated sectors of the Iberian coast with maximum arrival heights of 6 m within 21 and 35 min, which is too quick for current early-warning systems to operate successfully. These findings suggest that the tsunamigenic potential of strike-slip faults is more important than previously thought, and should be taken into account for the re-evaluation of tsunami early-warning systems ; This study was supported by the Spanish projects DAMAGE (CGL2016-80687-R AEI/FEDER), FAUCES (CTM2015-65461-C2-1-R), RNM148, B-RNM-301-UGR18 and AGORA P18-RT-3275 Junta de Andalucía. [.] Research partially funded by the Programa Operativo FEDER Andalucía 2014-2020, call made by the University of Jaén 2018. The ICM-CSIC authors acknowledge Severo Ochoa funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2019-000928-S) ; Peer reviewed

Abstract. The 1958 Lituya Bay landslide-generated
mega-tsunami is simulated using the Landslide-HySEA model, a recently
developed
finite-volume Savage–Hutter shallow water coupled numerical model.
Two factors are crucial if the main objective of the numerical simulation is
to reproduce the maximal run-up with an accurate simulation of the inundated
area and a precise recreation of the known trimline of the 1958 mega-tsunami
of Lituya Bay: first, the accurate reconstruction of the initial slide and then
the choice of a suitable coupled landslide–fluid model able to reproduce how
the energy released by the landslide is transmitted to the water and then
propagated. Given the numerical model, the choice of parameters appears to be
a point of major importance, which leads us to perform a sensitivity analysis.
Based on public domain topo-bathymetric data, and on information extracted
from the work of Miller (1960), an approximation of Gilbert Inlet
topo-bathymetry was set up and used for the numerical simulation of the
mega-event. Once optimal model parameters were set, comparisons with
observational data were performed in order to validate the numerical results.
In the present work, we demonstrate that a shallow water type of model is
able to accurately reproduce such an extreme event as the Lituya Bay
mega-tsunami. The resulting numerical simulation is one of the first
successful attempts (if not the first) at numerically reproducing, in detail,
the main features of this event in a realistic 3-D basin geometry, where no
smoothing or other stabilizing factors in the bathymetric data are applied.