Geodiversity and cultural heritage case study: Edinburgh
The modern urban landscape of Scotland is an intimate blend of geodiversity and cultural influences. In Edinburgh the physical landscape of the city is fundamentally shaped by its underlying sedimentary and volcanic rocks formed during the Devonian and Carboniferous.
Differential erosion over many millions of years has shaped the present landscape, with the more resistant volcanic rocks now forming the higher ground. The Braid, Blackford and Pentland Hills are remnants of volcanoes that were active around 400 million years ago; Arthur's Seat, Calton Hill, Castle Rock and the Craiglockhart Hills were formed by slightly younger volcanic activity around 350 million years ago.
Molten rock from the Arthur's Seat volcano was intruded between layers of sedimentary rock and now forms the spectacular dolerite escarpment that overlooks Holyrood Park and the Scottish Parliament. During the Quaternary, ice sheets eroded the bedrock, forming a streamlined, ice-moulded landscape.
Locally, the more resistant igneous rocks protected the sedimentary rocks on their lee sides, so that crag-and-tail landforms were produced, notably at Castle Rock and the Royal Mile, which now form the centrepiece of the Old Town, also a World Heritage site.
Geology is equally closely woven through the fabric of the city buildings. First worked to produce stone for Edinburgh Castle in the 17th century, Craigleith Quarry was one of the principal sources of building stone during the 18th and 19th centuries and its sandstone features prominently in the buildings of the New Town.
More recent building works have involved the use of stone from further afield in Scotland, notably the the Museum of Scotland (Clashach sandstone) and the Scottish Parliament (Kemnay granite and Caithness flags), adding to the urban geodiversity.
As part of a process of raising awareness of Earth heritage in the urban environment, 'naming stones' events have been held in Edinburgh to help reconnect the built and natural heritage in people's minds.