Midland Valley Geology
The geology of carboniferous of the Midland Valley of Scotland
Research Aims
This essay will cover the basic geology of the Midland Valley, the changes in structure and volcano activities during the carboniferous period.
General introduction of the Midland Valley
The carboniferous is a period between 290 and 360 million years ago(Ref 1,p.8,Scotland Through Time). The Midland Valley was covered with lots of rainforest and numerous of coral reefs flourished in the tropical seas. Volcanos eruptions form the Campsie Fells in the central of Scotland. There are also quite a few active volcanos such as The Arthur’s Seat, North Berwick Law and Galtron Hills. The Midland Valley is described as the major geological terrane located between the Highland Boundary fault and the Southern Upland Fault. Predominant rocks in Midland Valley are sandstones and high concentration of coal from Aryshire to East Lothian (Ref 1,P.46,Midland Valley). More prominent is the landscape of the igneous rocks. The basaltic lavas form the major upland hills, predominant being the Pentlands, Ochils, Sidlaws, Campsies and Kilsyth Hills. (Ref 1 P.64,Midland …show more content…
Valley). Many volcanic eruptions deposited sediments in the shallow sea, rivers and deltas. Many igneous can be found with an evidence of lavas, tuffs, plugs dykes and sills.
Glasgow is build on a field of drumlins of tills. (Figure 1, The distribution of rocks in Midland Valley in present, Scottish Geology, 2008)
The rock types of the Midland Valley in the Carboniferous
In the period of Carboniferous, the central Scotland was flooded by shallow tropical seas where corals, shellfish and other seawater creatures flourished and formed limestones.
Limestone is an organic sedimentary rock, it was buried under many layers of sediment and exposed and weathered on the surface. Furthermore the rapid evolution and colonization by land plants is responsible for the formation of coal deposits, which was one the most important resources the Scotland’s economics depended on. Coals were formed from plants remained. In late Carboniferous sandstone, siltstone, mudstone, seat earth and coal predominantly river-delta environment. Figure 1 shows that the carboniferous sedimentary rocks are dominating the central of the Midland Valley, also there are carboniferous igneous rocks located in the north-west and east of
Midland. (Figure 2, The structure of the Arthur’s seat in present, St. Andrews University
Carboniferous volcanic activity in Midland Valley
Most of the high ground are related to the lavas, volcanic plugs and sills in Devonian and Carboniferous age (Ref 3, P.124).During the Carboniferous period, the continents was stretched due to extension and allowed magma to rise up and form volcanos. The volcano activity began in the end of the Devonian (400 million years ago) and continued to the early Permian(290-280 million years ago). The Caledonian Mountains is formed by the melting of the mantle lead to thinning of the crust, caused by Lithospheric stretching and compression in early and mid Carboniferous period. The Clyde plateau basalt lavas were erupted 335 millions years ago with an area of 3000km2 over the Midland Valley and create a horseshoe-shaped outcrop in Glasgow. There were plenty of volcano vents in the Clyde Plateau and quite a few are located in the north. Also there were quite a few volcano sat on the east-Scotland such as the Arthur’s Seat and Salisbury Crags in Edinburgh. Figure 2 shows the rock features of Arthur’s Seat and has good evidence to proof it was formed in the period of Carboniferous.
(Figure 3, Scottish Journal of Geology, 2015)
The igneous Activity
Many igneous activity in Carboniferous were associated with lithospheric stretching. The intrusion of horizontal sills are mainly quartz and dolerite. The Midland Valley Sill is the most extensive sill.(Fig 2) The sill acts as a cap rock to potect the underlying sedimentary rocks from erosion(Ref 5, Tectonic & volcanic features in Fife: Hill of Tarvit Area: Geological Events - Igneous Activity). The sill rocks form high ground in Midland Valley and they are very resistant. Figure 3 shows the timeline of the igneous activity between the end of Permian and Carboniferous. The Strathclyde Group has the most complicated formation than the others. The formation were mainly occur in the period of Visean.
Research Aims
This essay will cover the basic geology of the Midland Valley, the changes in structure and volcano activities during the carboniferous period.
General introduction of the Midland Valley
The carboniferous is a period between 290 and 360 million years ago(Ref 1,p.8,Scotland Through Time). The Midland Valley was covered with lots of rainforest and numerous of coral reefs flourished in the tropical seas. Volcanos eruptions form the Campsie Fells in the central of Scotland. There are also quite a few active volcanos such as The Arthur’s Seat, North Berwick Law and Galtron Hills. The Midland Valley is described as the major geological terrane located between the Highland Boundary fault and the Southern Upland Fault. Predominant rocks in Midland Valley are sandstones and high concentration of coal from Aryshire to East Lothian (Ref 1,P.46,Midland Valley). More prominent is the landscape of the igneous rocks. The basaltic lavas form the major upland hills, predominant being the Pentlands, Ochils, Sidlaws, Campsies and Kilsyth Hills. (Ref 1 P.64,Midland …show more content…
Valley). Many volcanic eruptions deposited sediments in the shallow sea, rivers and deltas. Many igneous can be found with an evidence of lavas, tuffs, plugs dykes and sills.
Glasgow is build on a field of drumlins of tills. (Figure 1, The distribution of rocks in Midland Valley in present, Scottish Geology, 2008)
The rock types of the Midland Valley in the Carboniferous
In the period of Carboniferous, the central Scotland was flooded by shallow tropical seas where corals, shellfish and other seawater creatures flourished and formed limestones.
Limestone is an organic sedimentary rock, it was buried under many layers of sediment and exposed and weathered on the surface. Furthermore the rapid evolution and colonization by land plants is responsible for the formation of coal deposits, which was one the most important resources the Scotland’s economics depended on. Coals were formed from plants remained. In late Carboniferous sandstone, siltstone, mudstone, seat earth and coal predominantly river-delta environment. Figure 1 shows that the carboniferous sedimentary rocks are dominating the central of the Midland Valley, also there are carboniferous igneous rocks located in the north-west and east of
Midland. (Figure 2, The structure of the Arthur’s seat in present, St. Andrews University
Carboniferous volcanic activity in Midland Valley
Most of the high ground are related to the lavas, volcanic plugs and sills in Devonian and Carboniferous age (Ref 3, P.124).During the Carboniferous period, the continents was stretched due to extension and allowed magma to rise up and form volcanos. The volcano activity began in the end of the Devonian (400 million years ago) and continued to the early Permian(290-280 million years ago). The Caledonian Mountains is formed by the melting of the mantle lead to thinning of the crust, caused by Lithospheric stretching and compression in early and mid Carboniferous period. The Clyde plateau basalt lavas were erupted 335 millions years ago with an area of 3000km2 over the Midland Valley and create a horseshoe-shaped outcrop in Glasgow. There were plenty of volcano vents in the Clyde Plateau and quite a few are located in the north. Also there were quite a few volcano sat on the east-Scotland such as the Arthur’s Seat and Salisbury Crags in Edinburgh. Figure 2 shows the rock features of Arthur’s Seat and has good evidence to proof it was formed in the period of Carboniferous.
(Figure 3, Scottish Journal of Geology, 2015)
The igneous Activity
Many igneous activity in Carboniferous were associated with lithospheric stretching. The intrusion of horizontal sills are mainly quartz and dolerite. The Midland Valley Sill is the most extensive sill.(Fig 2) The sill acts as a cap rock to potect the underlying sedimentary rocks from erosion(Ref 5, Tectonic & volcanic features in Fife: Hill of Tarvit Area: Geological Events - Igneous Activity). The sill rocks form high ground in Midland Valley and they are very resistant. Figure 3 shows the timeline of the igneous activity between the end of Permian and Carboniferous. The Strathclyde Group has the most complicated formation than the others. The formation were mainly occur in the period of Visean.