Tectonics and Structural Geology

The power and pitfalls of compliments

Anne Pluymakers January 19, 2022

Credit: cottonbro. Distributed via Pexels.

Part of a good workplace vibe is good contact between colleagues, as well as good contact between you and your supervisor – or between you and your supervisee. A potentially complex ingredient is the power of compliments. Compliments, per definition, are meant well. However, they can backfire enormously, when they are not received in the spirit in which they are meant. Additionally, part of being ...[Read More]

Geomythology. Hawaii islands and the journey of Pele

Filippo Carboni January 12, 2022

A painting of the Goddess Pele, PELEHONUAMEA (Photo credit: Herb Kane)

Hotspot Theory How would you explain a series of volcanoes in the middle of the ocean such as the Hawaii, the Midway or the Canary islands? J.T. Wilson, in 1963, suggested they are formed by relatively small, long-lasting, and exceptionally hot regions of magma located beneath the Earth crust, so-called “hotspots” (Wilson, 1963). Firstly, he applied this idea to the Hawaiian Islands, but the conce ...[Read More]

TS Must-Read – Molnar & England (1990): Late Cenozoic uplift of mountain ranges and global climate change: chicken or egg?

The Must-read team January 7, 2022

The idea that the Pleistocene glaciation was caused by a late Cenozoic rise of mountain ranges had been developed since the mid 19th century. Although this original idea did not hold, new arguments for a relation between a late Cenozoic uplift of mountains and global cooling were presented from the 1970s onward. These arguments focused on how increased surface elevations would affect the albedo, t ...[Read More]

Extensional tectonics at oceanic transform faults: a new perspective on plate tectonics

Yu Ren November 24, 2021

Viscosity structure of the oceanic transform fault revealed by geodynamic simulations. Credit: Grevemeyer et al., 2021.

Yu Ren is a PhD candidate at GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany. He uses three primary tools to study marine tectonics: geomorphology, seismology, and numerical modelling. His PhD project is on the structural and tectonic characterization of oceanic transform faults. Oceanic transform faults (OTFs), usually considered as first-order tectonic segmentation of mid-ocean r ...[Read More]

Geomythology. Japan’s Earthquakes – The work of Namazu?

Filippo Carboni October 22, 2021

Namazu the giant catfish (image credit: pinktentacle.com).

Welcome to this first post on the EGU TS blog’s newest series on Geomythology. Plate tectonic theory has existed for just over half a century but the Earth beneath us has always been active. In this series we explore historical and mythological explanations to tectonic phenomena we now understand, such as earthquakes, volcanoes, mountains, and others. Japanese Earthquakes Japan is one of th ...[Read More]

Features from the Field: Sheath Folds

Samuele Papeschi and Hannah Davies October 4, 2021

Spectacular sheath folds in Cap de Creus (Spain), produced by deformation in a Variscan shear zone. Photo by Dr. Melanie Finch.

Shear zones are areas of intense deformation that localize the movement of one block of the crust with respect to another. In previous posts, we have seen that shear zones contain some very deformed rocks called mylonites, lineations that tell us the direction of movement, and useful kinematic indicators, such as S-C fabrics, that allow geologists to understand which way the rocks moved. However, ...[Read More]

GeoMod 2021 in Utrecht: connecting on-site and online

Hanneke Heida and Elenora van Rijsingen September 27, 2021

Group picture of the on-site participants of GeoMod 2021 in front of the venue Landgoed Zonheuvel. Credit: the GeoMod organisers.

After a year and a half in which all of us have had to become accustomed to meeting our colleagues and collaborators only in digital space, it was finally time for an in-person conference again. From 19-23 of September 2021, the ninth edition of GeoMod took place in a conference center outside sunny Utrecht (the Netherlands). The organizing committee, led by Ernst Willingshofer, Ylona van Dinther, ...[Read More]

TS Must-Read – England and Molnar (1990) Surface uplift, uplift of rocks, and exhumation of rocks

The Must-read team September 20, 2021

With this paper, England and Molnar (1990) shed light on the recurrent confusion in the uses of terms ‘uplift’ and ‘exhumation’. The main focus is to clarify the difference between surface uplift, uplift of rocks, and exhumation by explaining the differences and the relations between these processes (Fig. 1). The manuscript also illustrates how other processes, such as changes in climate, can be m ...[Read More]

TS Must-Read – Dahlen (1990) Critical Taper Model Of Fold-and-thrust Belts And Accretionary Wedges

The Must-read team September 13, 2021

Dahlen 1990‘s paper presents a synthesis of all theoretical work on accretionary wedges that had begun more than a decade earlier, with the fold and thrust belts research of Elliott (1976), Chapple (1978), and model by Davis et al., (1983). Dahlen expanded previous views with a more sophisticated treatment of pore-fluid pressure using volume-averaged Stokes-equations for both solids and flui ...[Read More]

TS Must-Read – Lister and Davis (1989) The origin of metamorphic core complexes and detachment faults formed during Tertiary continental extension in the northern Colorado River region, USA

The Must-read team September 6, 2021

Lister and Davis (1989) is a seminal article for core complexes and detachment faults, cited well over a thousand times. The authors describe geometry and kinematics of core complexes, cropping out in the USA, which result from lithosphere extension. The paper carefully describes the main detachment fault separating lower plate from upper extending plate and discusses the role of granitoid intrusi ...[Read More]