Sand and gravel resources, Sheet 97 Fraserburgh, Cainozoic of north-east Scotland
From: Merritt, J W, Auton, C A, Connell, E R, Hall, A M, and Peacock, J D. 2003. Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland).
Sheet 97 Fraserburgh
The principal resources of sand and gravel on Sheet 97 (P915374) are of four types.
- Moundy glaciofluvial ice-contact deposits, which occur between New Aberdour and Loch Strathbeg.
- Terraced glaciofluvial sheet deposits, which occur between Peathill and Rathven, and north-east of Loch of Strathbeg.
- Concealed deposits of glaciofluvial gravel in the vicinity of Howe of Byth pit (Appendix 1 Site 6).
- Spreads of blown sand, which back the coast between Fraserbrugh and Rattray Head.
Peacock (1983) has described these deposits in some detail. The glaciofluvial deposits are assigned to the Blackhills Sand and Gravel Formation (Chapter 8). Although predominantly sandy, the kettled, ice-contact deposits are typically very variable in grain size over short distances. Many of the deposits occur as coarsening-upward deltaic sequences (Peacock and Merritt, 2000d). As well as the ubiquitous clasts of hard metamorphic and igneous rocks, some of the more gravelly units contain sparse shells and clasts of soft sedimentary rocks (of Triassic, Jurassic and Early Cretaceous ages). Typical sections occur in pits near Blackhills (at NJ 926 609 and NJ 926 615) (P104110).
The terraced glaciofluvial deposits are composed predominantly of gravel derived from the local bedrock, but some of the lower lying spreads pass laterally into silt and clay. Considerable amounts of blown sand have accumulated adjacent to Loch Strathbeg. Along the coast, the blown sand is mainly medium grained and composed of quartz with minor amounts of feldspar; shell fragments and small pebbles are present locally. Several deeply weathered outcrops of Devonian conglomerate constitute potential sources of coarse gravel in the area to the west of New Aberdour. This material, which is decomposed to a depth of several metres locally, also extends on to the adjoining Banff sheet.