The geology of the area around Woodlands View is interesting and varied.  It is the reason why coal mining and stone quarrying have scarred the countryside and explains why the landscape is as dramatic as it is.

 

Panorama of Woodlands View

 Click on the above image to see an interactive version which you can zoom into

Woodlands View is at the southern edge of Todmorden Moor. The moor contains Carboniferous rocks (380-250 million years old). The rocks include sandstones, gritstone, mudstones (shale), coal seams and fireclay. The Carboniferous Period is when a lot of England’s coal was formed.

Interesting fossils can be found in these rocks, but the rocks themselves can also be worthy of note.

At first, much of rock underneath Woodlands View seems to be shale. The shale is easily weathered which is why it is exposed in the steeper sides of the valley. Some of the shale contains fossils and is stained yellow due to the presence of sulphur. Iron Pyrite can be found in small amounts on nodules, and a rainbow coloured rock that is possibly Peacock Ore (Bornite, a Sulphide mineral) can also be found. There are also deposits of coal, although most of this has been mined out in the past, so we only find small amounts.

 

 

Higher up on the moor behind us are sandstones and gritstones.  These rocks are more resistant to erosion, so form the flatter upland plateaus. There are spoil heaps left behind from mining that comprise of coal, shale, carbonate nodules and other minerals. 

If any geologists can tell us more about these rocks, Nettie would be very grateful.

Numerous Carboniferous fossils can be found in some of the spoil heaps left over from the coal mining. These fossils pre-date the dinosaurs and are from a time when the UK was located nearer to the equator. During the Carboniferous, the area that is now Woodlands View was probably covered in forests of ferns and club mosses. Shallow seas later inundated these forests, which are why both land based and marine fossils can be found.

 

 

Fossils that Nettie has unearthed include:

Goniatites- a type of mollusc that is an extinct form of ammonoid.  They look similar to ammonites to non-experts like Nettie.

Flat-shelled Gastropods- they look like snails and are a type of mollusc.

Dunbarella (Sp.)- a marine bivalve that lived in ancient shallow seas.

Marine Boullions- big hard balls of rock containing marine fossils including bivalves and gastropods. This particular example is 30 cm in diameter and has a mass of about 25 kg.

Lepidodendron – ‘tree like’ plants that grew in carboniferous forests.  Now extinct, fossils show that they could grow to heights of 30m. They are sometimes referred to as ‘scale trees’ due to the scale like marking on their fossilised trunks.

Stigmaria- this is the name given to parts of the root of carboniferous plants such as Lepidodendron. It is not always possible to identify what plant the root came from.

Coal balls – these are really interesting to people studying palaeobotany (the study of ancient plant life).  Coal balls are so called because they are found in coal seams.  They are not actually made of coal, nor are they always ball shaped either.   Coal balls are made from peat, which was permineralised by calcium and magnesium carbonates, forming a limestone concretion.  Apparently coal balls used to really annoy coal minors because they are so hard compared to the coal that the machines would break.

Coal balls are important because they contain marvelously preserved plant fossils and can include pollen, plant cells and spores.  These can give us a clue about what the environment was like a long time ago and help us to picture what some of the plants might have looked like.  Coal balls are also quite rare which makes the study of them all the more important.

The coal balls that are found in Todmorden are between 325- 280 million years old.

Nettie’s coal balls range in size from 5cm to 15 cm across.

 

 

 

Just a short walk up onto Todmorden Moor is a geology and heritage trail.  This takes you on a roughly 5.5 km walk around the moor following markers and interpretation boards.  It is well worth a visit but you do need to be careful as it is fairly rough and there are old areas of mining that can be dangerous. If you see an area of ground that looks like the image below then stay clear as there is a risk that the ground could collapse underneath you.

 

Danger Areas 

The land surrounding Todmorden is divided roughly East and West by a system of fault lines. Two Major Faults, the Deerplay and Cliviger Faults run roughly North West to South East with smaller faults running East to West, complicating the situation and giving the 'Todmorden Smash Belt' its name. The faults provide weak zones for weathering and erosion to shape the landscape. The Pennines rose towards the end of the Carboniferous Period as the result of the collision of two tectonic plates. Erosion and weathering has exposed coal measures, sandstones, mudstones to varying degrees, but with a marked difference East and West of Todmorden.

Geology of the Todmorden Area