Sunday, January 25, 2015

St Brides Bay A Journey Back In Time


St Brides Haven
I leave St Brides Haven with the aim to bridge a section of the Pembrokeshire coast I have yet to complete from here to Solva, otherwise known as St Brides Bay.

Stack Rocks from Halfway Rock (the Camel formation is clear to the left of Stack Rocks)
Forecast wasnt the best but with five kids currently over my house I take my chances and escape the madness. Force 4-5 possible 6 North Easterly, sea state moderate, showers. I figured this section of the coast should be mostly sheltered from the worst of the winds.
Syncline fold in the Old Red Sandstone
The geology either side of St Brides Haven is mainly Old Red Sandstone, which make the cliffs really stand out.

Nearing Mill Haven you can clearly see where the Old Red Sandstone ends and is replaced with the Grey Igneous Rock of the Pre-Cambrian period. It was a really dull miserable day, not good for taking photos.

Through Howney Stone opposite Stack Rocks the sea state picked up with brisk wind causing waves to break. A lone Razor Bill was bobbing about in the waves, most have now migrated for the winter.

The grey igneous rocks are now distinctively different to the deep red cliffs near St Brides. This irregular belt between Mill Haven and Little Haven is known as the Johnston Series and are the oldest rocks in Pembrokeshire (well over 1,000 million years).

The old igneous headlands are more typical in the north of Pembrokeshire, Dinas Head, Stumble for instance. South Pembrokeshire is mainly made up of sediments which are much younger.
From Musselwick just before Little Haven the geology turns to coal measures made up of Sandstone and Shales, Millstone Grit and thin Anthracite Coal Seams. These are the youngest rocks in Pembrokshire (280 million years old).

I got very close to an Otter in this cove, I dont think he saw me. Although by the time I removed my gloves to get my camera out he disappeared beneath the water.


Layers of alternating stone can clearly be seen here up on the cliff. Black Mudstone collected on the sea floor then as they shallowed a thin layer of fine sandstone sits on top. Thick layers of Sandstone lay on top of that from delta deposits, bleached due to leaching in a tropical environment.

Extreme folds in the sediment can be seen at either ends of the bays at Little and Broad Haven.


Shag Rock with Broad Haven in background
Its now easy to understand how St Brides Bay has been formed. The brittle softer rock has given way to the ongoing pounding of the sea forming shallow bays cut into the coal measures leaving harder sandstones at the headlands.

Sleek Stone
At the end of Broad Haven beach is an impressive Monocline formation (asymmetrical up-fold in the strata) known as Sleek Stone. The rock resembles a huge beached whale with a big bite out of it!

Following the coast toward Druidston, named after a 12th century knight who settled here, the cliffs show more evidence of the erosion that continues to eat away at the cliffs.

Haroldston Bridge
It is now low tide so I am unable to pass under Haroldston Bridge, a natural arch linking a small rocky outcrop to the main cliff.

I stop off at a small inaccessible bay just prior to Druidston Haven but its too cold to stop for long. I dont know why maybe its the miserable weather but I didnt have the motivation in me to carry on any further. So I continue on a little further with Rickets Head south of Newgale in view before turning back.

I paddle into the small sheltered lagoon under Haroldston Bridge on the way back for a cuppa to warm me up.
Whilst having a cuppa I caught a sight of a Peregrine leaving the cliff with what looked like a small bloodied rodent in its talons.

Passing Broad Haven the surf which was more evident earlier had ceased so I landed at Small Haven in front of this impressive looking cave.

Continuing my journey the sea state got worse the further south I went. I decide not to make the small detour out to Stack Rocks.

I chased this Curlew most of the way back, every time I got within shooting distance he flew off. I finally managed to get this shot.

It made for some good rock-hopping opportunities amongst the red stones with the tide being so low. It also kept me out of the wind.

Typically the sun decided to show its face when I got back to St Brides Haven so I took a short walk up the coastal path to The Nab Head.

St Brides Bay and Stack Rocks

Ramsey Island basking in the sun

There was a Kestrel hovering above the cliff who didnt seem bothered about my presence. A bit further along two pigeons flew down amongst the cliffs at break neck speed quickly followed by another Peregrine. Good day for wildlife!

So I didnt get to my intended destination but I had an enjoyable paddle none the less. I saw my first otter and got a few glimpses of some fascinating birds that occupy this coast. Please correct any of my geological jargon if Im wrong, Im learning.

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