A description is given of overconsolidated sub-till clay sediments situated about 260 m a.s.l., i.e. 90 m above the local marine limit of the last deglaciation. The clay sediments contain neither macro- nor micro-fossils. Textural, mineralogical and geochemical investigations, strongly supported by the Ce deficient lanthanide abundance pattern, indicate marine depositional environment. The clay sediments are assumed to be of Middle-Weichselian age and are thus correlated with the Sandnes Interstadial, described from SW-Norway, and its analogues.
Overconsolidated sub-till clays in Herlandsdalen, lower Numedal, south Norway