Folding at Broadhaven
Pembrokeshire, SW Wales
One of The Geological Society's 100 Great Geosites. Asymmetric folds in interbedded Carboniferous siltstones, shales and coal horizons are cut here by a number of northward-propagating thrusts. This classic structure has been studied in some detail (e.g. Williams and Chapman,1983) as it provides an excellent outcrop example to examine the interplay between faulting and folding during deformation.
Trevayne
Pembrokeshire, SW Wales
Large-scale harmonic fold within Carboniferous siltstones, shales and coal horizons. Close inspection of the fold core reveals several low offset thrust segments which probably formed to accommodate the relatively tight interlimb angle here. The cross-section below shows the transition in structural style between this location, Monkstone Point and Saundersfoot.
Trevayne
Pembrokeshire, SW Wales
Large-scale harmonic fold within Carboniferous siltstones, shales and coal horizons. Close inspection of the fold core reveals several low offset thrust segments which probably formed to accommodate the relatively tight interlimb angle here. The cross-section below shows the transition in structural style between this location, Monkstone Point and Saundersfoot.
Multi-phase folding, Boyne Limestone
NE Scotland
These thinly bedded, greenish grey and cream units of the Boyne Limestone Formation (Argyll Group) were deposited in a shallow marine setting and later folded during the Caledonian Orogeny (390-490 Mya). The Caledonian Orogeny deformed and metamorphosed large tracts of Europe, America and North Africa; this small outcrop (c. 100cm x 25cm x 25cm) near Portsoy, NE Scotland, records some of this deformation at a macro scale.
Complex fold patterns are recorded in these thin interbeds of calc-silicate rocks, metalimestones and calcareous semipelites of Neoproterozoic age (541-1000 Mya). The dominant folding pattern here is associated with a third phase of Caledonian deformation (D3) which overprints an earlier D1 phase, resulting in fold interference patterns which can be seen on some surfaces.
Lat: 57° 40' 56"N, Long: 2° 38' 37"W
