5 Murchison’s View
The changing landscape
The view in front of you takes in Dudley Castle on the adjacent limestone hill. Beyond the castle the ground rises up to Rowley Hills that are made of the igneous rock, dolerite/microgabbro intruded into the landscape 307 million years ago. The panel in front of you (and inset in picture above) shows how this landscape was in the 1830’s when Murchison came here to study the local rocks.
Sir Roderick Impey Murchison was a Scottish geologist who lived from 1792 to 1871. Murchison’s significance to the Wren’s Nest, was that he established the Silurian System, of which the rocks of this hill are a part.
View of central Birmingham from Murchison’s View. The ground between here and Birmingham is underlain by clays and sandstones of the Carboniferous time. You are standing at the top of a quarry face that falls away in front of you. This was where they mined the Silurian Lower Quarried Limestone for two centuries. Etchings in the art collection of Dudley Museum show that here in 1800 the hill had been completely stripped of all trees. Since that time mother nature has naturally re-vegetated this hill.
Today this landscape is managed by on site wardens and their volunteers so that we can keep these views open to be enjoyed by all visitors. The view that you see shows how the rocks below the surface dramatically affect the nature of the landscape above them. The hard rocks like the limestones and dolerite are resistant to weathering and stand as tall hills. Between the hills the softer rocks such as the clays and sandstones of the coal field are more easily worn away and become the low-lying valleys between the hills.
Look at the rock face behind you.
What direction are these rock beds dipping? How does that compare with the dip direction you have seen previously?
Dipping away to the west and in the opposite direction are the correct answers. You are now looking at the western arm of the arched fold that forms the Wren’s Nest Hill. The fault zone would be visible if rocks were exposed just beyond the right side of the picture.
The dip of the beds on the western arm of the anticline (pericline) is not as steep as that on the eastern side. The dip here is about 40 degrees to the west. On the next leg of this Voyage, as you walk along the western arm of the pericline, looking northwards, the oldest rocks will be to your right, getting younger to your left.
Do Task 5
Do Task 5 before moving off.
Walk back along the way you came, then at the marker post follow the path around to your left.
Task 5 Questions
What is the name of the City you can see on the horizon to the east?
What rocks form the Rowley hills?