On a large, glacially transported mass of Lower Cretaceous rock at Leavad in the County of Caithness

Abstract

The section seen in the sand-pit at Leavad near Rangag, twelve miles W.S.W. of Wick, has been described in two papers, printed in the Transactions of this Society: the first, on “Egg-shaped stones dredged from Wick Harbour”2 the second, “On Cretaceous Rocks in Caithness.”3 In the latter paper the finding of fossils in the large nodular masses of sandstone imbedded in the sand of the pit was recorded. These fossils were determined by Dr Lee and Dr Hitchin, Palaeontologists to the Geological Survey, to be of Lower Cretaceous (Neocomian) age. It was also said that the sand and sandstone are parts of the same deposit, the cementing material having been removed in solution from what is now sand, while the nodular masses of sandstone, in which the fossils are found, are the more durable parts of the same deposit still retaining their calcareous cementing material. Whether this Cretaceous deposit rested on boulder clay or on the flagstones of the Old Red Sandstone formation was an important point which was left unsettled. There was no section showing what underlay the sand, and no direct evidence was then obtained to determine whether this deposit was in situ or was a mass transported by ice. The occurrence of an isolated patch of Cretaceous rock, which was seen to be not less than 130 yards long, far distant from any other rocks of Cretaceous age, the nearest being those of Skye, Mull, and Morvern, was considered of sufficient interest to warrant the further investigation