Tectonics and Structural Geology

TS Must-Read – Cowie (1998) A healing-reloading feedback control on the growth rate of seismogenic faults

The Must-read team April 4, 2022

This study provides a simple numerical model of fault rupture that describes the development of fault systems from the initial nucleation of numerous small faults to the localisation of deformation into few major faults. The model presented is based on two main considerations: first, earthquakes cause stress changes that can either advance or delay failure on neighbouring faults. Second, for failu ...[Read More]

TS Must-Read – Caine et al., 1996 Fault zone architecture and permeability structure

The Must-read team February 21, 2022

Caine et. al. (1996) is a cornerstone paper which describes, compares and quantifies brittle fault zones and their permeability (fluid flow) properties from observations. Doing so, the paper initiates the accumulation of information on the permeability of brittle fault zones described previously (Randolph and Johnson 1989; Scholz 2019; Byerlee 1993). The study begins by defining fault zones as com ...[Read More]

Features from the Field: Shear Zones and Mylonites

Samuele Papeschi, Sandra McLaren and Hannah Davies January 25, 2021

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]

TS Must-Read – Mckenzie and Parker (1967) The North Pacific: an example of tectonics on a sphere

The Must-read team September 30, 2020

The paper describes how large, rigid, aseismic regions can be defined with Euler’s theorem, which describes the geometry of motion on a sphere, i.e. the Earth’s surface. Points on these large and rigid blocks move in relation to other blocks describing small circles set by their rotation pole. The paper describes this as “paving stone theory”, where tectonic plates are “paving stones”, and success ...[Read More]

Patience Anne Cowie (1964 – 2020): A Geology Superhero

Anouk Beniest June 23, 2020

An artists illustration of Patience Cowie (credit: Annique van der Boon)

Welcome to the first post in a new series being hosted on the TS blog! This series “Influential women of Tectonics and Structural Geology” is aimed at highlighting women who have had a key contribution to the field of tectonics and/or structural geology. Patience’s contribution to the field of faults changed the way geologists looked at faults. Her work continues to be used to an ...[Read More]

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]

Minds over Methods: The faults of a rift

Åke Fagereng June 5, 2019

Looking south along the Malawi rift, with escarpment to the right and Chilwa Intrusions in the valley floor. Credit: Åke Fagereng

Do ancient structures control present earthquakes in the East African Rift? Åke Fagereng, Reader in Structural Geology, School of Earth and Ocean Sciences, Cardiff University For this edition of Minds over Methods, we have invited Åke Fagereng, reader in Structural Geology at the School of Earth and Ocean Sciences, Cardiff University. Åke writes about faults in the Malawi rift, and the seismic ha ...[Read More]