Primary Sedimentary Structures from the Precambrian of Southeastern Sweden

Abstract

Abstract The Precambrian meta-sedimentary rocks of the Vastervik area, along Sweden's southeast coast, exhibit many well-preserved primary sedimentary structures. Cross-bedding, measuring from one cm to three m in amplitude, is the most common depositional feature preserved, other than the bedding sequences as such. Tabular and trough cross-beds occur in many variations. The Precambrian meta-sedimentary rocks of the Vastervik area, along Sweden's southeast coast, exhibit many well-preserved primary sedimentary structures. Cross-bedding, measuring from one cm to three m in amplitude, is the most common depositional feature preserved, other than the bedding sequences as such. Tabular and trough cross-beds occur in many variations. Taken together, abundant cross-bedding (often of a channel-fill type), flow structures, minor graded bedding, mud cracks, and oscillation ripple marks indicate that deposition in this Precambrian area was relatively rapid, and took place in a shallow-water environment, most likely...