Detrital rutile geochemistry and thermometry as guides to provenance of Jurassic-Paleocene sandstones of the Norwegian Sea

Abstract

This paper explores the potential for use of rutile geochemistry as a provenance tracer in Jurassic-Paleocene sandstones in hydrocarbon exploration wells from the Norwegian Sea. Previous studies in this area, concentrating on provenance-sensitive heavy-mineral ratios, garnet geochemistry, tourmaline geochemistry, and detrital zircon geochronology, established the presence of five distinct sand types (MN1, MN2a, MN3, MN4, and MN5), sourced from different parts of the Norwegian and Greenland landmasses to the east and west of the basin. Approximately 50 rutile grains from two samples of each of these sand types have been analyzed by laser ablation inductively coupled plasma mass spectrometry. Differences in Cr and Nb contents indicate that there are significant variations in the relative abundance of rutiles derived from metamafic and metapelitic sources, with Norwegian-sourced sandstones (MN1, MN3 and MN5) having higher proportions of metamafic rutile compared with Greenland-sourced sandstones (MN2a and MN4)