Calton Hill
Also within
Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| SK116713 | — | Favourable | 5.15 | 2012-01-26 |
| SK119711 | — | Favourable | 5.15 | 2012-01-26 |
Geology & landscape
Mining / Industrial: Quarry · Geological Period: Carboniferous · Rock Type: Basalt
Landscape processes: Volcanic / Igneous
Description
Area, 6.5 ha. 16.0 ac. Description This largely restored quarry is of considerable importance to geologists because of the occurrence of a very rare rock type within the basalt lavas which are exposed here. The Calton Hill area was the site of a volcanic vent during early Carboniferous times, some 330 million years ago and the basalt lavas occur within the vent. The lavas contain nodules of rocks known as spinel lherzolites and harzburgites, which originated from very deep within the Earth’s crust and which were brought to the surface during the volcanic activity. Consequently, such rocks are very rare and this is the only locality in England at which they are found. Their study enables geologists to understand better the processes which take place within volcanic complexes.