(Inclined Devonian Cliffs) - 2004
The main rocks of the area are of the Devonian period and are mainly mudstones that have been altered into weak slates, they are strongly inclined and to the east of the beach a fault divides the rocks between the Portscatho formation in the west and the Pendower formation to the east.
Running along the back of the bay is a fine example of a raised beach. This was formed relatively recently within the last 2 million years and shows that the sea levels were once higher than at present, this raised beach sits directly upon the Devonian rocks and is a classic example of unconformity, as the rocks that span the period in between (approx. 350 million years) have completely disappeared.
Occasionally after winter storms a submerged forest is uncovered which contains many familiar species of trees, it’s thought that these forests which can be found all over the South West are around 3 thousand years old and show that unlike at the time of the raised beach the sea levels were many metres lower during the ice ages.
Apart from microfossils from the Portscatho rocks there are no fossils to be found in either the cliffs or raised beach, the whole area is protected by SSSI status so please do not hammer or disturb the cliff formations. To collect fossils we need to head to the eastern end of the bay and travel back in time to
the Ordovician period.
For anyone interested in the Late Devonian, further East at Carne, the Carne Formation of the Devonian are part of the Givetian stage.
| Ordovician |
Abundant Exotic Blocks of Quartzite and Limestone within Devonian Breccias and Conglomerates (The Veryan Series).
Caused by unstable sedimentological conditions
such as submarine faulting.
|
|
Devonian |
Late |
Famennian |
354 to 364 |
| Frasnian |
364 to 370 |
Middle |
Givetian |
370 to 380 |
| Eifelian |
380 to 391 |
Early |
Emsian |
391 to 400 |
| Praghian |
400 to 412 |
| Lochkovian |
412 to 417 |
|
FORMATIONS AND DEPOSITS |
LOCATIONS |
M
I
D
D
L
E
R
E
D
S
A
N
D
S
T
O
N
E |
Carne Formation |
Pendower Beach |
| Millbuie Sandstone Group |
Eathie
Balintore
Cromarty
Tarbat Ness
|
| Strath Rory Group |
|
| John O'Groats Sandstone Group |
John o' Groats |
Upper Caithness Flagstone Group |
Mey Subgroup |
Thurso |
| Ham-Skarfskerry Subgroup |
Thurso |
| Latheron Subgroup |
Thurso |
| Spital Beds |
Thurso
Spittal |
| Achanarras & Niandt Limestone Member |
Achanarras |
| Lower Caithness Flagstone Group |
Robbery Head Subgroup |
|
| Lybster Subgroup |
| |
|
|
FORMATIONS AND DEPOSITS |
LOCATIONS |
| Hangman Sandstone Formation |
Minehead |
| Walls Hill Limestone |
|
| Lummaton Shell Bed |
|
| Pendower Formation |
Pendower Beach |
| Daddy Hole Limestone |
Daddy Hole (Torquay)
Hopes Nose (Torquay)
|
M
I
D
D
L
E
R
E
D
S
A
N
D
S
T
O
N
E |
Col-Bheinn Formation |
|
| Smeorail Formation |
|
| Lower Caithness Flagstone Group |
Hillhead Red Bed Subgroup |
|
| Berriedale Flagstone Formation |
|
| Berriedale Sandstone Formation |
|
| Clyth Subgroup |
|
Badbea Breccia /
Ellen's Geo Con |
|
|
1:250 000 Geological Map of Lands End District
Geological Maps are sold either Flat or Folded for Solid, or Seabed geology. Special editions may be available for certain locations. For a complete list click the link below.
Click here to BUY ONLINE from our Store |
|
1: 50 000 Geological Map of Falmouth Area
Geological Maps are sold either Flat or Folded for Solid, Drift or combined geology. Special editions may be available for certain locations. For a complete list of
1: 50 000 maps, click the link below.
Click here to BUY ONLINE from our Store |
