ALBERT

Description: The Makran subduction zone has produced M 8+ earthquakes and subsequent tsunamis in historic times, hence indicating high risk for the coastal regions of southern Iran, Pakistan, and neighboring countries. Besides this, the Makran subduction zone is an end-member subduction zone featuring extreme properties, with one of the largest sediment inputs and the widest accretionary wedge on Earth. While surface geology and shallow structure of the offshore wedge have been relatively well studied, primary information on the deeper structure of the onshore part is largely absent. We present three crustal-scale, trench-perpendicular, deep seismic sounding profiles crossing the subaerial part of the accretionary wedge of the western Makran subduction zone in Iran. P-wave travel-time tomography based on a Monte Carlo Markov chain algorithm as well as the migration of automatic line drawings of wide-angle reflections reveal the crustal structure of the wedge and geometry of the subducting oceanic plate at high resolution. The images shed light on the accretionary processes, in particular the generation of continental crust by basal accretion, and provide vital basic information for hazard assessment and tsunami modeling

Description: In September 2017 three crustal-scale seismic profiles were acquired in southern Iran covering the subaerial accretionary wedge of the western part of the Makran Subduction zone. Each of the roughly north-south trending profiles was approximately 200 km long, and on each profile 9 to 10 artificial shots with charges between 400 and 800 kg of explosives were fired. The seismic signals were observed by 300 autonomous digital recorders with geophones on each profile. This dataset consists of the raw (continuous) data of the recorders (in proprietary cube format and MSEED-format) and the shot records in SEGY-format (standard exchange formats).

Description: Two recent tsunamis in late 2018, in Sulawesi and Anak Krakatau, Indonesia, strikingly demonstrated the high vulnerability of communities to tsunamis induced by landslides and volcanic mechanisms. Both tsunamis were the result of a chain (cascade) of events: on 28 September in Palu, on the island of Sulawesi, the cascade consisted of a sequence of earthquake - landslide - tsunami, while on 22 December, after a prolonged period of volcanic activity, a flank failure occurred on Anak Krakatau, which in turn triggered a tsunami (Walter et al, 2019). In both cases, the resulting tsunamis caught the local population largely unprepared and caused a high number of fatalities. This has been attributed to the limited understanding of tsunami generation from mechanisms other than fault rupture and the lack of an effective tsunami warning system for non-seismic events. Both events have raised questions in the Indonesian society and among the relevant authorities about appropriate strategies for improved preparedness, early warning and mitigation for such events. The German-Indonesian project "TsunamiRisk" aims to help answer these questions through applied geoscientific and social science research aimed at developing policy recommendations and enabling transfer into practice. The perspective of local communities must be given special consideration, as it is ultimately they who are confronted with the direct impacts of such events on the one hand and who must implement better preparation and long-term mitigation on the ground on the other. Therefore, the project investigates the specific framework conditions as well as existing experiences in Indonesian communities with previous earthquake/tsunami events in order to support the discussion about adequate strategies and approaches for preparedness, early warning and mitigation of non-seismic tsunami hazards at the local level. The starting point for all this is to have a better understanding of the tsunami threats that communities face. The present study is intended to make a contribution to this.

Description: Tsunamis constitute a significant hazard for European coastal populations, and the impact of tsunami events worldwide can extend well beyond the coastal regions directly affected. Understanding the complex mechanisms of tsunami generation, propagation, and inundation, as well as managing the tsunami risk, requires multidisciplinary research and infrastructures that cross national boundaries. Recent decades have seen both great advances in tsunami science and consolidation of the European tsunami research community. A recurring theme has been the need for a sustainable platform for coordinated tsunami community activities and a hub for tsunami services. Following about three years of preparation, in July 2021, the European tsunami community attained the status of Candidate Thematic Core Service (cTCS) within the European Plate Observing System (EPOS) Research Infrastructure. Within a transition period of three years, the Tsunami candidate TCS is anticipated to develop into a fully operational EPOS TCS. We here outline the path taken to reach this point, and the envisaged form of the future EPOS TCS Tsunami. Our cTCS is planned to be organised within four thematic pillars: (1) Support to Tsunami Service Providers, (2) Tsunami Data, (3) Numerical Models, and (4) Hazard and Risk Products. We outline how identified needs in tsunami science and tsunami risk mitigation will be addressed within this structure and how participation within EPOS will become an integration point for community development.