Seismicity and Seismic Risk in the Offshore North Sea Area

Section 1: Geology and Tectonics.- Tectonics of the North Sea Basin and their possible relation to historical earthquakes.- North Sea seismotectonics and the role of geology in offshore seismic risk assessment.- Constraints on seismo-tectonic models for the North Sea.- What happens to the Rhine Graben “sub-plate boundary” where it meets the S. North Sea?.- Geology and tectonics. Panel Discussion. Introductory remarks.- Note: Possible neotectonic fault movements in Norway.- Discussion.- Section 2: Seismicity.- Seismicity of the North Sea Area.- Some problems concerning the seismicity of the North Sea area.- Non-random distribution of earthquakes in the North Sea basin area.- Seismicity and neotectonic structural activity of the Rhine Graben system in Central Europe.- Removal of Ghosts.- (presented by Hoang Trong Pho)/ Commentaires sur une carte seismique de la Mer du Nord et de la Mer de Norvège.- Discussion.- Section 3: Tides, Ocean Waves and Sea Level Changes.- Tidal research and seismicity.- Changes of relative mean sea-level and of mean tidal amplitude along the Dutch coast.- Extreme values of wind speed and wave height in the North Sea for defining design criteria of offshore installations.- Note: Seaquakes, an hazard to offshore platforms?.- Discussion.- Section 4: Instrumentation.- Instrumentation for North Sea seismic data acquisition.- Strong motion earthquake data acquisition and processing.- Ocean bottom seismic instrumentation.- Testing methods related to soil- and structure behaviour under dynamic loading.- Note on the detection and location capability of the Netherlands seismic stations for earthquakes in the North Sea basin.- Discussion.- Section 5: Soilmechanics, Liquefaction, Geotechnology.- Some remarks on the contribution of geo-technicalengineering to an estimation of seismic risk.- Problems in soil mechanics and earthquake engineering in the North Sea.- Seismic data requirements for the design of fixed platforms in the offshore North Sea area.- Evaluation of stability of North Sea sites.- Seismology: a geotechnical engineer’s view point.- Testing for liquefaction potential.- Modeling of strong ground motion from earthquakes.- Discussion.- Section 6: Risk Analysis.- Evaluation of seismic risk.- Seismic risk and the North Sea.- On some problems concerning seismic risk assessment for offshore structures in the North Sea.- Uncertainty in U.K. seismic hazard analysis 377.- Methodological aspects encountered in the Lower Rhine area seismic hazard analysis.- Outline of procedure for total seismic risk estimation.