The Late Precambrian succession in north-west Oscar II Land, Spitsbergen

• Published in: Geological Magazine
• Main Author: Waddams, P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1983
• Subjects: Northern Norway; Oscar II Land; Spitsbergen
• Online Access: http://dx.doi.org/10.1017/s0016756800025437; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0016756800025437

Summary This paper describes the late Precambrian rocks in north-west Oscar II Land, western Spitsbergen, with particular emphasis on an upper (Haaken Formation) and lower (Trondheimfjella Formation) diamictite sequence. It is argued that both diamictites are glacigenic, formed by ice-rafting over distal turbidite basins, and correspond to the two Varangian tillite horizons of northern Norway and elsewhere. This leads to a radical reinterpretation of the age of the Oscar II Land succession, much of which now appears to be Vendian. With the exception of the Trondheimfjella Formation, which records an early phase of deepening of the depositional basin, the lower half of the succession (St Jonsfjorden Group) comprises mainly shallow water shelf sediments. The upper half of the succession (Comfortlessbreen Group) was deposited within a basinward prograding turbidite fan system, with the Haaken Formation representing the distal component of the complex. A return to a mixed clastic-carbonate shelf environment is recorded by the overlying Palaeozoic rocks.