Geograph - photograph every grid square

The whole of the eastern side of the Strathaird peninsula is bounded by low cliffs of the Druim an Fhuarain Sandstone Member of the Bearreraig Sandstone Formation of Aalenian to Bajocian stages (oldest Middle Jurassic). Although this is called a sandstone, the geological map key describes it as sandstone, cross-bedded and sandy limestone, massive or thinly bedded with fragments of crinoid ossicles, bivalve, bryozoans, belemnite and brachiopod fragments. The member is up to 485m thick, and quite variable. The soluble nature of the cement between sand grains means that the rock is easily eroded by solution, but being on the sheltered side of this bit of land, has not been washed away by wave action. The cross-bedding is thus shown up by deep etching of the surface of the cliff. Much more recently than the deposition of the sandstone, during the split that opened up the Atlantic Ocean, much igneous activity took place in parts of Western Scotland, and that is reflected here by the intrusion of basalt of Palaeogene age, most noticeably as NW-SE trending dykes (at right angles to the coast) which give rise to numerous geos, beloved of sea kayakers for poking into.