The Tranearth Group is a

Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago (Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoi ...

lithostratigraphic Lithostratigraphy is a sub-discipline of stratigraphy, the geological science associated with the study of strata or rock layers. Major focuses include geochronology, comparative geology, and petrology. In general, strata are primarily igneous ...

group A group is a number of persons or things that are located, gathered, or classed together. Groups of people * Cultural group, a group whose members share the same cultural identity * Ethnic group, a group whose members share the same ethnic ide ...

(a sequence of

rock strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as e ...

) in the southern Lake District and

Howgill Fells The Howgill Fells are uplands in Northern England between the Lake District and the Yorkshire Dales, lying roughly within a triangle formed by the towns of Sedbergh and Kirkby Stephen and the village of Tebay.

of the

Pennines The Pennines (), also known as the Pennine Chain or Pennine Hills, are a range of uplands running between three regions of Northern England: North West England on the west, North East England and Yorkshire and the Humber on the east. Commonly ...

of northern

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...

. The name is derived from the locality of Tranearth near

Torver Torver is a village and civil parish in the South Lakeland district of Cumbria, England, south west of the village of Coniston and west of Coniston Water. Farming has always played an important part in Torver's history, though slate mining in ...

Cumbria Cumbria ( ) is a ceremonial and non-metropolitan county in North West England, bordering Scotland. The county and Cumbria County Council, its local government, came into existence in 1974 after the passage of the Local Government Act 1972. ...

. The Group is included within the

Windermere Supergroup The Windermere Supergroup is a geological unit formed during the Ordovician to Silurian periods ~, and exposed in northwest England, including the Pennines and correlates along its strike, in the Isle of Man and Ireland, and down-dip in the Southe ...

. It comprises laminated hemipelagites and

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, ...

s and some

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates ...

s and

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms wh ...

which achieve a thickness of between 500 and 1000m. It is divided into a lower Brathay Formation which is overlain by the Birk Riggs Formation (not present in the Howgills) and then by an upper Coldwell Formation.

References

* {{Refend Silurian System of Europe Geology of England Geological groups of the United Kingdom Geologic formations of the United Kingdom