Tinted detail of a photo: Aerial view of steep limestone mountain ridges whose pale rock layers are tilted almost vertical, with green grassy slopes between them, a deep shadowed valley and a building with a mast on the left summit.
TS
Tectonics and Structural Geology

Features from the field

Pathways of force within granular layers

Pathways of force within granular layers

Earth’s surface is covered by many kinds of granular materials, including sediments and soils. Below ground, grains are also widespread in unconsolidated deposits and fault zones; even polycrystalline rocks deep inside the Earth are made up of mineral grains. These materials deform under their own weight and external forces, but what forces act inside them? …[Read More]

Exploring Earth’s interior with analogue models: The case of slow earthquakes

Analogue experimental setup of spherical hydrogel suspension.

Have you ever heard of “analogue modelling”? In solid Earth science, directly observing the Earth’s interior is challenging, and the analogue modelling approach often overcomes this limitation by using alternative systems analogous to natural phenomena. By identifying fundamental mechanisms in these tractable systems, we can apply physical scaling laws to understand processes deep within the …[Read More]

Using drones for geological mapping

This image shows a drone operator guiding a drone to its landing spot.

Geological teaching and education is fast-changing in the 21st century. While fieldwork has long been considered to be the bedrock of geological instruction, over time an increased acceptance has developed for the need to make geological education and training more accessible, especially with regard to fieldwork as this can often involve days and weeks of …[Read More]

How Lava Domes Grow: Field Observations and Thermo-Mechanical Insights from the 1979 Soufrière Eruption

How Lava Domes Grow: Field Observations and Thermo-Mechanical Insights from the 1979 Soufrière Eruption

To kick off the New Year, we have invited a guest author, Takafumi Maruishi, a researcher in the Research Division for Volcanic Disasters / Center for Volcano Research Promotion, National Research Institute for Earth Science and Disaster Resilience, Japan. He explains the scaling law of lava dome growth and its physical insight. Effusive eruptions—when magma …[Read More]

Where earthquake faults reach the ground surface: insight from 2016 Kumamoto event

Where earthquake faults reach the ground surface: insight from 2016 Kumamoto event

What does a seismogenic fault look like? We can sometimes observe surface earthquake faults, which propagate ruptures from the hypocenter to the ground surface. In 2016, intense seismicity was observed during the Kumamoto earthquake sequence in Japan. This sequence consisted of many shallow earthquakes, including a strong foreshock and the subsequent mainshock with numerous aftershocks. …[Read More]

Features from the Field: S-C fabrics

Features from the Field: S-C fabrics

As we have seen in previous Features from the field posts, structural fabrics are both informative and spectacular. But many structural geologists will list a shear zone fabric, such as mylonite, as their favourite! As Samuele, Hannah and I wrote in a previous post, shear zones are regions of intense deformation where rocks have accommodated …[Read More]

Features From the Field: Pencil Cleavage

Features From the Field: Pencil Cleavage

This edition of ‘Features from the field’ is brought to you by Sandra McLaren, a senior lecturer at the University of Melbourne. She will be talking about type of rock formation called “Pencil Cleavage” so called because it looks like pencils. Sandra even has a small collection of pencil/crayon shale which is the cover image …[Read More]