This report describes the activities of the SAT_UHRS_2022 sea campaign carried out from May 10 to 15, 2022, aboard the RV Diplodus, operating from the port of Sesimbra. The main objective of this campaign was to carry out sea acceptance tests (SAT) for new components that were recently integrated into the ultra-high resolution seismic (UHRS) reflection data acquisition system of the Marine Geophysics Laboratory...
The SW Portuguese margin has been intensively studied, particularly for rifting, tectonic inversion and tectonic reactivation of the Atlantic passive margin. In this work we bring new data on the continental shelf, usually not acquired by the heavier geophysical methods (e.g. airborne or low resolution deep seismic-magnetic surveys). These new data allow casting a clear light bridging between the geological str...
The occurrence of sedimentary layers indicating high energy events is common in the continental shelves sedimentary record. Their presence has been usually related either to tsunami waves or storm waves. In both cases, the identification of the transport mechanism requires a variety of proxies. This work presents the preliminary results of the analysis of a gravity core (MW-107) collected at ca. 57 m water dept...
The MINEPLAT project (Assessment of the mineral resources potential in the continental shelf of Alentejo and of the environmental conditions caused by the tectonic uplift in the PlioceneQuaternary) allowed acquisition of 1700 km of ultra- high resolution seismic profiles, and full coverage of multibeam bathymetry and acoustic backscatter of 1450 km2 and 1940km of magnetic data of the Alentejo continental shelf,...
The Tagus River ebb-delta is located near an important city center off Lisbon, Portugal. The Tagus delta hosts various kilometer scale landslides, the most important of which has been mapped and described with a presumable age of ~11 ky and 10 km in length, 4 km wide and 20 m of maximum thickness. An equivalent area of gas trapped in the sediments has also been reported (Terrinha et al., 2019). The TAGUSGAS pro...
This paper synthesizes the geology of the Atlantic Margin off the coast of Iberia and surrounding Abyssal Plains using published thematic mapping freely downloadable from EMODNET-Geology portal at different scales. Selected information was chosen in order to highlight mineral occurrences and natural hazards overlaid on geological and morphological maps. Altogether, this information is published and interpreted ...
Outer shelf sedimentary records are promising for determining the recurrence intervals of tsunamis. However, compared to onshore deposits, offshore deposits are more difficult to access, and so far, studies of outer shelf tsunami deposits are scarce. Here, an example of studying these deposits is presented to infer implications for tsunami-related signatures in similar environments and potentially contribute to...
The Sines Contourite Drift (SCD), located in the Alentejo margin, southwest Iberian continental margin, has been through many depositional phases in result of dimatic variations and bottom current oscillations, which determined a variable depositional pattern and an irregular sedimentary evolution since the Late Pleistocene. The SCD, being in the main path of the Mediterranean Outflow Water (MOW), which greatly...
The importance of tsunami hazard assessment is only possible if a complete dataset of events is available, allowing the determination of the recurrence intervals of the tsunamis adapted to local and regional conditions. One possible way to know these intervals is to study the offshore sedimentary record, looking for sediment remobilised and transported by the incoming tsunami waves and generated backwash curren...
Outer shelf sedimentary records are promising for determining the recurrence intervals of tsunamis. However, compared to onshore deposits, offshore deposits are more difficult to access, and so far, studies of outer shelf tsunami deposits are scarce. Here, an example of studying these deposits is presented to infer implications for tsunami-related signatures in similar environments and potentially contribute to...