Pembrokeshire geology

Broad Haven (south) to Stackpole Head Viewed from Stackpole Head, cloud-streets of cumulus set off the land and seascape looking towards Barafundle bay just left of centre. To the right, the light grey Carboniferous Limestone gives way to cliffs of 'Old Red Sandstone'.

Broad Haven (south) to Stackpole Head The cliffs of Stackpole Head consist of Carboniferous Limestone gently dipping south. There are sea caves and other solution features visible: the prominent bedding plane just below the cliff top displays palaeo-karst pot-hole-like features. Caldey Island is on the centre skyline; Llanmadoc Hill and Rhosili Down on the Gower Peninsula can be seen in the far distance just above the headland.

Broad Haven (south) to Stackpole Head Viewed from Mowingword Point, Mowingword Bay, backed by Gun Cliff, is inaccessible except by sea or climbing down the cliffs (climbing equipment and experience needed). The prominent Pinnacle Stack is in the middle of the bay. Church Rock just offshore from Broad Haven (S) is visible in the upper left. The flat, Tertiary age '200-foot erosion surface' is well seen in this photo.

Broad Haven (south) to Stackpole Head Immediately inland from Box Bay in the previous photo is the 'Sandy Pit' doline; a large karst solution hollow. There is a connection with the sea at the base, so marine erosion has probably contributed to the enlargement of the hollow. The name 'Sandy Pit' possibly refers to a partial filling with post-glacial blown sand (subsequently largely exploited and excavated?) This panoramic view shows the large size of the doline and consists of three landscape photos stitched together with Photoshop software.

Broad Haven (south) to Stackpole Head Immediately inland from Box Bay in the previous photo is the 'Sandy Pit' doline; a large karst solution hollow. There is a connection with the sea at the base, so marine erosion has probably contributed to the enlargement of the hollow. The name 'Sandy Pit' possibly refers to a partial filling with post-glacial blown sand (subsequently largely exploited and excavated?) The sea stack of Church Rock is visble in the distance to the left of centre.

Broad Haven (south) to Stackpole Head Just east of Broad Haven and Saddle Point is Box Bay with well developed sea-caves at its eastern end. Can you see the climbers? The rocks are Carboniferous Limestone. Box Bay is sometimes known as Sandy Pit Bay (after the doline just inland of the bay). Neither names are used on the Ordnance Survey maps. The headlands of Mowingword and Stackpole Head are at the far right. This is a panoramic view consisting of two landscape photos sticthed together using Photshop software. Also taken using a polarising filter. I'm pleased with how the clouds have turned out.

Broad Haven (south) to Stackpole Head Just east of Broad Haven and Saddle Point is Box Bay with well developed sea-caves at its eastern end. Can you see the climbers? The rocks are Carboniferous Limestone. Box Bay is sometimes known as Sandy Pit Bay (after the doline just inland of the bay). Neither names are used on the Ordnance Survey maps.

Broad Haven (south) to Stackpole Head Church Rock sea stack, with its steeple-like point lies just off shore from Broad Haven. This is a view from Saddle Pooint at the eastern end of Broad Haven. The rocks here are Carboniferous Limestone. There are two Broad Havens in Pembrokeshire. This is the southern one (the other is in the west in St Brides Bay).

Broad Haven (south) to Stackpole Head This is a view from the western end of Broad Haven, looking east towards the Carboniferous Limestone cliffs of Stackpole Head. Caldey Island is on the distant skyline. There are two Broad Havens in Pembrokeshire. This is the southern one (the other is in the west in St Brides Bay).

A beautiful summer's day on the Pembrokeshire Coast Path above the western end of Marloes Sands, looking over to Gateholm Island and Gateholm Stack, with Skokholm Island on the skyline. The rocks here are Devonian age 'Old Red Sandstone'. Such a contrast in weather to when I was last here!

A view over the small inlet of Victoria Bay near Marloes in Pembrokeshire. Slabs of Silurian age sandstones dip at about 40° to the south.

A view over the small inlet of Victoria Bay near Marloes in Pembrokeshire. Skokholm Island is visible in the distance. Slabs of Silurian age sandstones dip at about 40° to the south.

St Brides Haven in Pembrokeshire shows off her colours! Red sandstones and mudstones of the Devonian age Old Red Sandstone contrast with the turquoise sea on this beautiful summer's day. The rocks are gently folded into a series of open anticlines and synclines, visible on the far side of the inlet. The white building is Cliff Cottage (available for holiday let).

St Brides Haven in Pembrokeshire shows off her colours! Red sandstones and mudstones of the Devonian age Old Red Sandstone contrast with the turquoise sea on this beautiful summer's day. The rocks are gently folded into a series of open anticlines and synclines, visible on the far side of the inlet. The prominent building on the left skyline is St Brides Castle, a 19th-century baronial country mansion.

Solifluction deposit ('head') on the east side of St Brides Haven, Pembrokeshire. This consists of a jumbled mass of angular sandstone fragments derived from the underlying Old Red Sandstone and was formed by freeze-thaw action at the end of the last glacial period. These deposits would have been part of the permafrost layer which partially melted during the summer months, refreezing again during the winter. Small-scale fold-like features near the base are cryoturbation structures, probably due to ice-wedging as the refreezing permafrost layer expanded upwards. The walking stick is about 0.9 m long.

Druidston Haven geology: Cliff Section 1 interpretation Interpretation No.1 of a series of six photos and interpretations to illustrate the geology of Druidston Haven, Pembrokeshire. Photo No.1 of a series of six photos and interpretations to illustrate the geology of Druidston Haven, Pembrokeshire. The background is a panoramic view of two photos stitched together using Photoshop software. The cliffs of Druidston Haven mostly consist of Ordovician (Caradocian) age shales with some thin sandstones. During the Caledonian orgogeny at the end of the Silurian period, these were deformed into a series of mostly upright open folds. These were then re-folded by Variscan movements at the end of Carboniferous, to become largely recumbent (near horizontal) or partly inverted, facing down towards the south. The Ordovician rocks form a horst - a ridge or block of strata faulted against younger rocks on either side. The Druidston Horst is bounded by the South Druidston Boundary Fault at the south end of the Haven, and the North Druidston Boundary Fault at the north end. These photos show the section midway along the horst from the stream to the Southern Boundary Fault at the far end.

Druidston Haven geology: Cliff Section 1 Photo No.1 of a series of six photos and interpretations to illustrate the geology of Druidston Haven, Pembrokeshire. This is a panoramic view of two photos stitched together using Photoshop software. The cliffs of Druidston Haven mostly consist of Ordovician (Caradocian) age shales with some thin sandstones. During the Caledonian orgogeny at the end of the Silurian period, these were deformed into a series of mostly upright open folds. These were then re-folded by Variscan movements at the end of Carboniferous, to become largely recumbent (near horizontal) or partly inverted, facing down towards the south. The Ordovician rocks form a horst - a ridge or block of strata faulted against younger rocks on either side. The Druidston Horst is bounded by the South Druidston Boundary Fault at the south end of the Haven, and the North Druidston Boundary Fault at the north end. These photos show the section midway along the horst from the stream to the Southern Boundary Fault at the far end.

Druidston Haven geology: Cliff Section 2 interpretation Interpretation No.2 of a series of six photos and interpretations to illustrate the geology of Druidston Haven, Pembrokeshire. The cliffs of Druidston Haven mostly consist of Ordovician (Caradocian) age shales with some thin sandstones. During the Caledonian orgogeny at the end of the Silurian period, these were deformed into a series of mostly upright open folds. These were then re-folded by Variscan movements at the end of Carboniferous, to become largely recumbent (near horizontal) or partly inverted, facing down towards the south. The Ordovician rocks form a horst - a ridge or block of strata faulted against younger rocks on either side. The Druidston Horst is bounded by the South Druidston Boundary Fault at the south end of the Haven, and the North Druidston Boundary Fault at the north end. These photos show the section midway along the horst from the stream to the Southern Boundary Fault at the far end.