NJG75-4-04
1995
Stacked fluviodeltaic cycles in the Upper Proterozoic Godkeila Member, Varanger Peninsula, northern Norway
75
4
pp. 229-242

The Upper Proterozoic Godkeila Member in the Persfjorden area (Varanger Peninsula) comprises four stacked fiuviodeltaic cycles, 70-200 m thick. Four facies associations have been distinguished: (A) prodelta sandy turbidites; (B) silt-dominated delta front; (C) sand-dominated delta front; and (D) sandy, braided alluvial plain. Each cycle is a shoaling-upward succession of associations B-+ ( ±A) -+ B -+C-+ D. The characteristics of the facies associations suggest a fiuvial-dominated delta with low-gradient braided rivers entering a relatively low-energy, tide-inliuenced basin. The stratigraphy of the individual cycles suggests progradation under an overall relative rise in sea level. The erosional surface between the fiuvial and marine associations may, in contrast, represent a minor relative fall in sea leve! and thus a forced regression. The cycle termination is attributed to an intermittent, possible fault-controlled shift of the depocentre. The considerable regional thickness variations of the Godkeila Member (600-1450 m) along the depositional strike is thought to be mainly a result of differential subsidence.

Signe-Line Røe, Geologisk Institutt, Universitetet i Bergen, 5007 Bergen, Norway.

0029-196X