Memoria de tesis doctoral presentada por Miquel Camafort Blanco para obtener el título de Doctor en Ciencias de la Tierra por la Universitat de Barcelona (UB), realizada bajo la dirección del Dr. César Rodríguez Ranero y de la Dra. Eulàlia Gràcia i Mont del Institut de Ciències del Mar (ICM-CSIC).-- 266 pages, figures, This PhD thesis presents a geological and geophysical study that characterizes the Quaternary stratigraphy, geomorphology, recent tectonics, and discusses their implications to understand the geodynamic evolution of North Tunisia, including the emerged land and continental margin. The study area spans much of the region containing the boundary between the African and Eurasian tectonic plates in this sector. The onshore main structural pattern strikes in a NE-SW trend that extends offshore, into the North Tunisian continental margin plateau that is part of the same recent deformation system. I have carried out specific analyses of these two onshore and offshore regions where present-day tectonics has been previously poorly studied. Although some limited activetectonic studies had been carried out onshore, the offshore area was scarcely studied to date, and never explored in the detail presented in this work, let alone studied in an onshore-offshore integrative study. To carry out the joint study of the two regions we have had to take different methodological approaches.
Onshore Northern Tunisia we applied a morphometric relief analysis of digital elevation models based in drainage network metrics to characterize active tectonics and its influence into the drainage evolution of the area. This analysis was ground-truthed with a field campaign in March 2015 to examine the several morphometric anomalies obtained with the relief analysis carried out before. Our analysis indicates that recent river captures have been the main factor driving the fluvial network reorganization in Northern Tunisia. Morphometric indices evidence fluvial network reorganization that indicates that the catchment area of the Medjerda River has increased through time by capturing adjacent axial valleys to the east of its previous drainage divide. These captures are probably driven by the gradual uplift of adjacent axial valleys by reverse/oblique slip faults like El Alia-Teboursouk and Dkhila faults or associated folding. Our fieldwork discovered that these faults cut Pleistocene sediments and possible associated coseismic structures were identified, further supporting recent fault activity with estimated maximum magnitudes (Mw) of 6.7 and 6.5 respectively for each fault. [...], The author of this thesis has been supported by the project Geomargen-2 funded by Repsol and EU project EMODnet-HRSM. Additional funding has been obtained on the framework of SHAKE (CGL2011-30005-C02-02) and INSIGHT (CTM2015-70155-R) projects. This work was carried out within the Grup de Recerca Consolidat de la Generalitat de Catalunya Barcelona Centre for Subsurface Imaging (B-CSI) (2017SGR1662)

19 pages, 7 figures, 4 tables, A geomorphological analysis of the submarine landslides geographical information system catalogue of the Geological Survey of Spain has revealed three main groups of submarine landslides associated with (1) deep-ocean seamount ridges (extinct spreading centres), (2) volcanic islands and (3) continental margins. These three groups have statistically significant morphometric differences, as determined from analysis of variance (ANOVA) and Tukey's HSD Tests, in total length (runout), total area, maximum deposit width and bathymetric depth. Volcanic island-related slope failures affect larger areas of the seafloor and their headwall escarpments often extend above sea-level. Slope failures associated with seamount ridges are the deepest, between 3500 and 5500 m, and display relatively high width-to-length ratios. Finally, landslides on continental margins show two sub-groups. Landslides on tectonically controlled margins have smaller runouts and total area and larger average slope gradients than margins where tectonic controls are limited. These results demonstrate that submarine landslide morphology is strongly controlled by the geological-tectonic setting, This work has been supported by the EU-funded projects GARAH (GeoERA GE-1), EMODnet High Resolution Seabed Mapping (EASME/EMFF/2015/1.3.1.7/SI2.74125) and EMODnet Bathymetry–High Resolution Seabed Mapping (EASME/EMFF/2018/007). Funding was provided by the ‘Ministerio de Ciencia, Innovación y Universidades’ and the European Regional Development Fund through project INSIGHT (CTM2015-70155-R), Peer reviewed

12 pages, 8 figures, 2 tables, The development of overpressure in continental margins is typically evaluated with hydrogeological models. Such approaches are used to both identify fluid flow patterns and to evaluate the development of high pore pressures within layers with particular physical properties that may promote slope instability. In some instances, these models are defined with sediment properties based on facies characterization and proxy values of porosity; permeability or compressibility are derived from the existing literature as direct measurements are rarely available. This study uses finite-element models to quantify the differences in computed overpressure generated by fine-grained hemipelagic sediments from the Gulf of Cadiz, offshore Martinique and the Gulf of Mexico, and their consequences in terms of submarine slope stability. By comparing our simulation results with in situ pore pressure data measured in the Gulf of Mexico, we demonstrate that physical properties measured on volcanic-influenced hemipelagic sediments underestimate the computed stability of a submarine slope. Physical properties measured on sediments from the study area are key to improving the reliability and accuracy of overpressure models, and when that information is unavailable, literature data from samples with similar lithologies, composition and depositional settings enable better assessment of the overpressure role as a pre-conditioning factor in submarine landslide initiation, Davide Mencaroni was supported by a Marie Skłodowska-Curie Doctoral Fellowship through the SLATE Innovative Training Network within the European Union Framework Programme for Research and Innovation Horizon 2020 under Grant Agreement No. 721403. The Spanish ‘Ministerio de Economia y Competitividad’ and the European Regional Development Fund through grant CTM2015-70155-R (project INSIGHT) are also acknowledged, Peer reviewed

Cruise Report ImagiNg large SeismogenIc and tsunamiGenic structures of the gulf of cadiz with ultra-High resolution Technologies (INSIGHT), R/V Sarmiento de Gamboa, 30 September - 20 October 2019.-- 127 pages, 103 figures, 11 tables, annexes, This report contains exhaustive information on the objectives, activities, instrumentation used and preliminary data acquired during the 2nd Leg of the INSIGHT cruise, which started in Vigo (Spain) on September 30 and finished in Cadiz (Spain), on October 20, 2019, and took place on boardthe Spanish R/V BO Sarmiento de Gamboa. This 2nd Leg was aimed at imaging and characterizing, with the highest possible resolution, selected active seismogenic faults, large slope failures and investigate their relation with fluid seepage in the Gulf of Cadiz. The large-scale features of most of these elements, such as fault systems and slope failures have been previously mapped and characterized (i.e. geometry, dynamics and kinematics) during national and European projects and cruises. […], The survey was mainly funded through the Spanish ministry Plan Nacional Program (INSIGHT project, Ref. # CTM2015-70155-R) (Coordinators Roger Urgeles & Eulàlia Gràcia)

Memoria de tesis doctoral presentada por Cristina Sànchez Serra para obtener el título de Doctora en Ciències de la Terra por la Universitat de Barcelona (UB), realizada bajo la dirección de la Dra. Eulàlia Gràcia Mont y del Dr. Roger Urgeles Esclasans del Institut de Ciències del Mar (ICM-CSIC).-- 254 pages, figures, tables, annexes, The southwestern margin of the Iberian Peninsula, which includes the Gulf of Cadiz, is characterized by present-day active deformation mainly driven by the NW-SE trending convergence between the African and Eurasian plates. This area hosts some of the largest earthquakes that have occurred in Western Europe leading to major disasters such as the 1755 Lisbon earthquake and tsunami. In the SW Iberian margin there is not yet a complete understanding of the active tectonics and related contemporary sedimentary processes. Further to that, there is a lack of accurate parameters to properly characterize the main active faults, and produce high-quality models of fault rupture and subsequent tsunami generation and propagation.
To fill in, at least partially, these gaps of knowledge, this PhD Thesis develops the following research:
1) An analysis using a multi-scale dataset consisting of multi-beam echo-sounder, 2D multi-channel seismic reflection profiles and high-resolution sidescan sonar (TOBI) data of the Cape São Vicente area to identify the sedimentary and tectonic processes that developed in the region, the interaction between the two and how those gave origin to one of the largest canyons in the Atlantic Ocean. [...], The author of this PhD thesis has been supported by a four-year Pre-Doc FPI “Formación de Personal Investigador” grant (ref. BES-2016-078877) from “Ministerio de Ciencias e Innovación” between 2017 and 2021. The Spanish “Ministerio de Ciencia e Innovación” and the European Regional Development Fund are also acknowledged for funding through grant CTM2015-70155-R (project INSIGHT)

Memoria de tesis doctoral presentada por Davide Mencaroni para obtener el título de Doctor en Ciències de la Terra por la Universitat de Barcelona (UB), realizada bajo la dirección del Dr. Roger Urgeles Esclasans y del Dr. Jaume Llopart Serra del Institut de Ciències del Mar (ICM-CSIC).-- 251 pages, figures, tables, Contourite drifts are the depositional expression of bottom currents, which are capable of shaping the morphology of the seafloor by transporting, eroding and reworking marine sediments, and are distributed on continental slopes worldwide. Synchronous interaction between bottom currents and turbidity currents have been reported often in channel-levée systems where the thickness of the turbidity current exceeds that of the levées. Such interplay between along-slope and down-slope sedimentary process is one of the mechanisms by which “mixed turbidite-contourite systems” can originate. Being composed by the winnowed finest part of turbidity currents and potentially able to deposit at sedimentation rates of several m/kyr, mixed systems constitute a potential source of overpressure development in marine sediments.
The Alentejo basin is located in the northern edge of the Gulf of Cadiz (SW Iberian margin), from which is separated by the São Vicente Canyon, one of the most prominent geomorphological features in SW Iberia. The area is characterized by an extensive contourite depositional system, generated by the Mediterranean Outflow Water (MOW) bottom current. The Alentejo basin hosts multiple mass transport deposits (MTDs) and scars, which are typically considered to be triggered by the frequent seismic activity related to the movement of multiple active faults present in the area. The combined presence of a contourite depositional system, a deeply incised canyon, mass wasting processes and potentially seismogenic faults makes the Alentejo basin the ideal study area to assess: a) how does contour currents interact with sediments transported along deeply incised canyons? b) How does mixed contourite – turbidite systems affect the development of overpressure within marine sediments, and consequently the stability of submarine slopes? [...], This research received funding by the European Union’s Horizon 2020 research and innovating program under the Marie Sklodowska-Curie grant via project ITN-SLATE (grant agreement No 721403). The Spanish “Ministerio de Ciencia e Innovación” and the European Regional Development Fund are also acknowledged for funding through grant CTM2015-70155-R (project INSIGHT), Peer reviewed