TS
Tectonics and Structural Geology

rheology

TS Must-Read – Bürgmann and Dresen (2008): Rheology of the Lower Crust and Upper Mantle: Evidence from Rock Mechanics, Geodesy and Field Observations

February 2, 2024
TS Must-Read – Bürgmann and Dresen (2008): Rheology of the Lower Crust and Upper Mantle: Evidence from Rock Mechanics, Geodesy and Field Observations

In 2008 Roland Bürgmann and Georg Dresen published their Must-Read paper on the rheology of the lower crust and upper mantle, based on findings from the lab, the field and space. As stated in the introduction, “rheology is the study of the flow and deformation of all forms of matter,” and as such the rheology of the Earth’s lower crust and upper mantle is closely linked to the evolution and deform ...[Read More]

Features from the Field: Shear Zones and Mylonites

, and January 25, 2021
Features from the Field: Shear Zones and Mylonites
Dextral, ductile shear zones crosscut foliated schist at Cap de Creus (Catalona, Spain). Photo © Jordi Carreras

The San Andreas Fault in California, the Alpine Fault in New Zealand, or the Main Frontal Thrust in the Himalayas are some of the most famous and largest fault zones that accommodate the relative displacement between two adjacent crustal blocks. Such faults, however, represent only the shallower expression of something much bigger: a crustal shear zone. In the first 10 kilometers or so of the crus ...[Read More]

Features from the Field: Chevron Folds

June 12, 2020
Features from the Field: Chevron Folds
Chevron folds in the radiolarites from Batain, Oman. Photo © Simon Virgo via Imaggeo

Folds are among the most strikingly beautiful structures we can observe in rocks. There are several ways folds may form in rocks. For instance, folds in sedimentary rocks may develop by liquefaction of soft sediments, but the most common way to produce folds – and also my favorite – is by deformation. When rocks are compressed by tectonic forces, layers (or foliations) bend and warp, p ...[Read More]