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.
Glarus Thrust
Alps, E Switzerland
The Glarus thrust is a major thrust fault in the Alps of eastern Switzerland. Along the thrust the Helvetic nappes were thrusted more than 100 km to the north over the external Aarmassif and Infrahelvetic complex.
The thrust forms the contact between older (Helvetic) Permo-Triassic rock layers of the Verrucano group and younger (external) Jurassic and Cretaceous limestones and Paleogene flysch and molasse. The Glarus thrust crops out over a relatively large area in the cantons Glarus, St. Gallen and Graubünden, due to its horizontal orientation and the high local relief. Famous outcrops include those at Lochsite near Glarus (the town) and in a mountain cliff called Tschingelhörner between Elm and Flims (in the same cliff is a natural hole called the Martinsloch).