About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

CSPG Special Publications

Abstract


Intl. Symposium of the Devonian system: Papers, Volume II, 1967
Pages 1141-1147
Tectonic and Igneous Activity

Tectonic implications of Sedimentation in Spitsbergen and midland Scotland

P. F. Friend

Abstract

In many areas bordering the North Atlantic, vigorous Devonian earth-movements resulted in the formation of basins in which sediment accumulated above sea-level. Study of their depositional history provides information about the geometry, timing and processes of the late stages of Caledonian orogeny.

Both Spitsbergen and midland Scotland contain isolated basins in which are found thick accumulations of non-marine Devonian sedimentary strata. The Wood Bay Formation of Spitsbergen and the Lower Old Red Sandstone of midland Scotland were chosen for study and comparison. In each of the two selected areas the sediments are largely confined to a graben, with the boundary faults parallel to trends of pre-Devortian fold structures in the flanking blocks.

Isotopic age determinations of metamorphism and plutonism in these flanking blocks are very similar for both areas, as are the dates, based on palaeontological evidence, for the onset and duration of sedimentary down-warpings.

The lithological character and thickness of the stratigraphic sequences indicates that downwarping went on contemporaneously with deposition. Additional information about the location of the rising source areas comes from a study of palaeocurrents (Spitsbegen) and sediment derivation (midland Scotland). Sediment derivation work also allows the location of basin edges in parts of both areas.

The thickness of sediment, and the level of erosion in the source areas (as indicated by sediment composition) provide a measure of the amount of relative downwarp and uplift which occurred in different parts of the two basins. There is evidence that in north-east midland Scotland both downwarp and uplift were particularly strong.


Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24