Technical report for cruise 0206 - sampling for environmental geochemistry and sediment instability in fjrods of Western Norway

Abstract

A sampling cruise with NGU's research vessel \"Seisma\" to selected fjords inMøre and Romsdal and Sogn og Fjordane, western Norway was undertaken inJune-July, 2002. The objective of this crusie was to obtain sample material tostudy the fate of heavy metals and to gain understanding of their transportmechanisms, carrier phases, bioavailability, budgeting and provenances. Fjordsoccurring both in areas with relatively high and low natural heavy-metalbackground were sampled. Sample material from fjords with significantindustrial activities was also obtained. To facilitate the link betweeninorganic sediment geochemistry and metal abundances in fish and sea mussels,the sampling plans were coordinated with Fiskeridirektoratet and Oceanor whorun their own environmental programs that focus on biota.Sampling in Rogaland (Karmsundet\/Skudenesfjorden and the southwestern part ofBoknafjorden) was undertaken to obtain cores for dating of slide activity.Several slide scars have previously been mapped in Karmsundet\/Skudenesfjordenand in SW Boknafjorden with the aid of swath bathymetry and relatively lowresolution shalloww seismic data, but the age of these mass movements has sofar been unknown.A modified Niemistø corer was used as the sampling device throughout thecruise. Altogether 157 sediment cores were obtained. Typical penetration depths(core lenght) ranged between 0.4 and 0.6 m, but in areas with fluffy,unconsolidated sediments penetration depths up to 1.1 m were reached.