Tectonics and Structural Geology

fracture

Minds over Methods: Dating deformation with U-Pb carbonate geochronology

EGU Guest blogger August 16, 2019

Cathodoluminescence image of calcite vein in background, with 100 micron laser ablation spots overlain top right and U-Pb isochron overlain left. Image credit: Nick Roberts

For this edition of Minds over Methods, we have invited Nick Roberts, a research scientist at the British Geological Survey, working within the Geochronology and Tracers Facility (GTF) running a LA-ICP-MS laboratory. Nick has a background in ‘hard-rock’ geology, incorporating geochemistry, geochronology, and magmatic and metamorphic petrology across a wide range of tectonic settings, and is now in ...[Read More]

Features from the field: Boudinage

Samuele Papeschi May 19, 2019

Boudins of amphibolite layers (metamorphosed basalts) that were stretched within quartz schists (Norway). Photo credits © Haakon Fossen.

The Features from the Field series is back! In our previous posts, we have shown how rocks can deform during ductile deformation, producing folds. Folds very commonly develop in rocks when rock layers are shortened by tectonic forces in a specific direction. On the other hand, when layers are extended, we develop boudins. Boudins – the term comes from the French word for ‘sausage’ – are frag ...[Read More]