THE BOOK
Some of the ideas discussed in this blog are published in my new book called "The Stonehenge Bluestones" -- available by post and through good bookshops everywhere. Bad bookshops might not have it....
To order, click
HERE

Monday 19 January 2015

The biggest erratic in Pembrokeshire?


 The Sleek Stone -- a famous monoclinal fold in the Lower Coal Measures.  The erratic is to the north of this little peninsula -- best approached at low tide......


On thumbing through those Geological Survey Memoirs, I discovered a note in the Milford Memoir about a giant erratic beneath the cliffs of Broad Haven (the one on St Bride's Bay) made of "columnar blue quartz-porphyry" and derived almost certainly from Ynys Bery / Ramsey Island.  Its dimensions are approx 3m x 3m x 3m -- which would make it a 50-tonner by my estimation -- and comparable to the giant erratic at Freshwater Gut, near Croyde in Devon.  It's located about 100 yards north of the Sleek Stone, Broad Haven.

I have never seen it myself, but I feel an expedition coming on.........

The Sleek Stone is at the south end of this satellite image, and the giant erratic must be in the bay which we see here in the centre of the photo.

1 comment:

TonyH said...

Will again quote from the same book I mentioned in the recent "Erratics of Baggy Point.." Post just now. This is R.F.Bidgood's "Two Villages".

It isn't about the Freshwater Gut giant erratic, but the neighbouring cliffs, and I thought people would be amused by the Biblical comparison once made by Devonshire forefathers:-

"An interesting example of weathering can be seen between Morte Point and Rockham. Tiny fragments of rock and sand dashed against the comparatively smooth face of the slate cliff by the fury of the Atlantic gales have resulted in a pitted effect, giving the impression of hieroglyphics. Long ago the forefathers of the village saw a likeness to Moses' tablets of stone and gave Commandment Gut its name."