On 21 April 2007, an Mw 6.2 earthquake produced an unforeseen chain of events in the Aysén fjord (Chilean Patagonia, 45.5°S). The earthquake triggered hundreds of subaerial landslides along the fjord flanks. Some of the landslides eventually involved a subaqueous component that, in turn, generated a series of displacement waves—tsunami‐like waves produced by the fast entry of a subaerial landmass into a water body—within the fjord [Naranjo et al., 2009; Sepúlveda and Serey, 2009; Hermanns et al., 2013]. These waves, with run‐ups several meters high along the shoreline, caused 10 fatalities. In addition, they severely damaged salmon farms, which constitute the main economic activity in the region, setting free millions of cultivated salmon with still unknown ecological consequences.

In CE 1960, Lake Cucao on Chiloé Island in south central Chile was inundated by the tsunami of the Great Chilean Earthquake (Mw 9.5). The area of what is now the lake basin has been submerged since the end of the rapid postglacial sea-level rise and has recorded tsunami inundations in its sediment record since then. This study reconstructs the tsunami history of Lake Cucao. Reflection-seismic profiles and side scan sonar data of the lake reveal a tidal delta with a crosscutting channel, which controls the sedimentary environment in the coast-facing part of Lake Cucao. The convergent pattern of seismic reflections near this channel indicates that tidal currents were active in the lake at least episodically since the formation of a major unconformity with strong reflection amplitude, which records the onset of lacustrine sedimentation. A radiocarbon date at the base of one of the 21 collected sediment cores dates this reflector to ~3800 years BP. Little net vertical displacement (≤ 2 m) in combination with an outlet river channel that can act as a pathway for sediment transport appears to have maintained the sensitivity of Lake Cucao to record tsunami inundation. The sedimentary record contains 15 clastic layers which are interpreted as tsunami deposits. The confidence level on the tsunami interpretation depends on five site-specific criteria, which are: (i) high magnetic susceptibility of the sediment indicating high clastic content, (ii) cross core correlation indicating widespread deposition, (iii) acoustic reflector correlation to the sedimentary record (also indicating widespread deposition), (iv) presence of mud clasts, and (v) age correlation to known paleotsunamis in the area. In this way, eight clastic layers are interpreted as tsunami deposits with a high confidence level, five with a medium confidence level and two with a relatively low confidence level. This study adds a long paleotsunami record on a coastline where extreme tsunamis occur frequently and where long (>2000 years) paleotsunami records are still sparse.

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In Palaeogene times, the 'Southern Bight' of the North Sea functioned as an intracratonic, shallow-marine, siliciclastic basin and accumulated a few hundred metres of gently dipping sediment packages. A fine-scale seismic-stratigraphical model for the Palaeogene was formulated on the basis of a dense, high-resolution reflection seismic grid. In total 13 major seismic-stratigraphical units were defined, based on geometry and seismic facies characteristics. The seismic stratigraphy has been complemented with the results of four cored wells near the Belgian coast, containing a nearly continuous, 200m thick sediment succession of Eocene age. Facies analyses of these cores suggest that part of these sediments were deposited on a muddy shelf and part in a delta environment. Evidence from relevant onshore outcrops has been used to complete the geological history of the Palaeogene, with special emphasis on the Eocene. A sedimentation model for the Eocene is presented, and relative sea-level changes, regional tectonic events and changes in sediment input are discussed. Genetic interpretation of the various lithological units and the largescale architecture of the ramp-type margin enable evaluation of sequence-stratigraphical concepts, initially defined for a typical shelf-slope-basin section along an Atlantic-type continental margin.

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