Vade Member
Hordaland Group,
Lark Formation
Name
English/ Norwegian
Vade Member / Vadeleddet
Derivatio nominis
Vade is a giant from Norse mythology who wades across fjords.
Original definition
Isaksen, D. & Tonstad, K. 1989. A revised Cretaceous and Tertiary lithostratigraphic
nomenclature for the Norwegian North Sea. NPD-Bulletin, No. 5, 59 pp.
Lithology
The member consists of thinly interbedded, light green to grey, very
fine-grained sandstones and siltstones. These are glauconitic, slightly
micaceous and well sorted.
Thickness
The member is 72 m thick in the type well
2/2-1
and 60 m in the reference well
2/3-2
.
Geographical distribution
The formation has only been recovered in blocks 2/2 and 2/3.
Type well
Well name
2/2-1
.
Interval of type section (m)
From 2172 m to 2100 m in the type well 2/2-1.
Reference well
Well name
2/3-2
.
Interval of reference section (m)
From 1855 m to 1795 m in reference well 2/3-2.
Boundaries
Lower boundary (basal stratotype)
The lower boundary is recognized by a decrease in gamma-ray readings and an
increase in velocity from the claystones of the underlying
Lark Formation into the Vade Member.
Upper boundary (characteristics)
The upper boundary is characterized by an increase in gamma-ray response
and decrease in velocity from the Vade Member the claystones of the
Lark Formation.
Age
Late Oligocene.
Depositional environment
The sandstones of the Vade Member were deposited in a shallow marine
environment. Their deposition can be seen as a response to an eustatic
fall in sea-level or tectonic uplift in the area. A source area in the
east or northeast was suggested by Isaksen & Tonstad (1989).
Remarks
