Tag: Geology

Hoy by Mirran Hall

the layers of sandstone on the cliffs of Hoy as viewed from the sea

The layers of red and honey-coloured sandstone that make up the cliffs are between 380 and 370 million years old and date from the Devonian Period, when Scotland lay south of the equator and was part of a huge desert continent. – Scottish Geology Trust

The end of the Carboniferous ‘icehouse’ world

Sedimentary evidence for global climates 320 Ma ago. As well as the large tracts of glaciogenic sediments, smaller occurrences and examples of polished rock surfaces over which ice had passed show the probable full extent (blue line) of ice sheets across the southern, Gondwana sector of Pangaea (Credit: after Fig 7.3, S104, Earth and Space, ©Open University 2007)