Pre-Late Weichselian submerged rock platforms off Stonehaven

Abstract

The existence of rock platforms around Scotland which pre-date the Late Weichselian (equivalent to the Late Devensian) glaciation is becoming increasingly apparent ([Sissons 1981][1]; [Browne and McMillan 1984][2]). This note describes the occurrence of three such platforms in the offshore area around Stonehaven, on the east coast of Scotland. The evidence for the platforms is based on the interpretation of seismic lines as shown in Plate 1. The platforms have been numbered 1 to 3 for reference, and their areal extent is indicated in Figure 1. These features appear to be unique to this area; however, work is in progress to find equivalent features elsewhere. The platforms have a step-like appearance and can be considered to be horizontal in profile as they slope gently away from the coast with apparent gradients of 0.5 to 2 m per kilometre. Platforms 1 and 2 appear to trend sub-parallel to the present shoreline; the trend of platform 3 is uncertain. Platform 1 occurs at a depth of 30 m below sea level and is over 1 km in width. The nature and location of the shoreward termination of this platform is uncertain because the seismic data do not extend inshore. Platform 2 occurs at a depth of 45 to 50 m and is about 4.5 km wide. Both platforms are cut into Devonian strata and are overlain by a discontinuous veneer of till and lithic-dominated littoral sands and gravels derived from the till. Platform 3 is the broadest platform extending to 7.5 km, . . . [1]: #ref-2 [2]: #ref-1