Tuesday 14 August 2018

The Permian Bockram Breccia - rocks newer than Carboniferous near Westhouse

Wheyyy - not just pretty flowers and sedges and lichens in this blog.  

Today it's geology..

I am going to write up how I learned that there are rocks newer than Carboniferous around here..

Roger and Liz Neale led an excellent day for Craven Conservation Group on the special rock formation which shows up in the stream bed near their house.

The Permian Brockram breccia





Here is what I wrote for a press release:

Craven Conservation Group were led on an exciting trip to see the “Permian Brockam Breccia” exposure at the gill below Fellbeck Farm near Westhouse on Sunday 12th August. 

The fact that the stream was (almost) dry meant the group could explore the sunken stream bed. 

Twelve members and friends attended the day led by Roger and Liz Neale of Bank House, Westhouse. 

Roger gave an introduction to Local geology in the morning and the group helped him sort specimens and look at how different types of local rock were used in different parts of the building.

Oyster Mushrooms, Horsehair Fungi and Field Mushrooms were spotted on the walk.



Roger had run the event the previous day for Cumbria Wildlife Trust- Kirkby Lonsdale Group

Roger explained how

Breccia is rock that is made out of angular pieces of rock that have been cemented together with sand.  At the base of the hills at this end of Craven - e.g. Ingleborough - are ancient sandstones/slates. On top of these are rocks formed in the Carboniferous period:  limestone, then the Yoredale Series (sandstone, shale and limestone layers) and then millstone grit at the top.  In the next geological period, the Permian, (which began 289.9 million years ago) desert conditions prevailed. There was a huge fault (cliff) maybe 6000ft high. In the desert occasional flash floods brought a jumble of sand and rocks over the limestone cliff. Some of the cracked rocks got cemented together to from the breccia, now called the Permian Brockram.




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The next meeting of Craven Conservation Group is An Insect Day at Broadrake Farm (Near Ribblehead  SD 740792) on  Thursday 23 August, 2018.   10am - 4pm. We plan to open the moth trap at 10am.
Find and record species around wildlife pond, meadow, limestone outcrops, mosses, grasses and trees. Enjoy wonderful views! Bring a picnic or tea/coffee refreshments available, toilet facilities.
(to book parking please phone 015242 41357)  Location: Broadrake, Chapel-le-Dale, Ingleton, LA6 3AX Age: Accompanied children welcome  www.craven-conservation-group.org.uk

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