Credit: UC Davis

Ridgecrest shows how earthquakes damage Earth’s crust

Nearly 10 yrs of drone surveys at Merapi volcano highlights the importance of hydrothermal weakening and structures hidden beneath younger lavas. A fracture system that formed in 2012 was subsequently buried under new lava in 2018. Only a year later, the new lava dome that formed in 2018 showed signs of instability and collapse along the previously buried fracture system, implying that hidden weaknesses may be a key factor in controlling hazardous volcano collapse. Credit: Darmawan et al., (2022)

Hidden weaknesses within volcanoes may cause their collapse

The astonishing force of the Tonga volcanic eruption in January 2022 shocked the world, but the fact that this underwater volcano actually erupted came as less of a surprise to geoscientists using satellite data to study changes in the temperature deep below Earth’s surface. As part of the effort to understand the complexities of Earth’s interior, scientists working within ESA’s Science for Society 3D Earth project, have developed a state-of-the art model of the lithosphere, which is a term to describe Earth’s brittle crust and the top part of the upper mantle, and the sub-lithospheric upper mantle down to 400 km depth. The model combines different satellite data, such as gravity data from ESA’s GOCE mission, with in-situ observations, primarily seismic tomography. The model that show differences in temperature, or thermal structures, indicated that the Tonga volcano was due to erupt at some point. Credit: ESA/Planetary Visions

Deep down temperature shifts give rise to eruptions

The pink pumice, and its thermal history, provides an insight into underwater eruptions.

Pink pumice key to revealing explosive power of underwater volcanic eruptions

Drone images of craters formed at Sheep Mountain. Credit: Kent Sundell, Casper College.

Secondary cratering on Earth: The Wyoming impact crater field

The Kumano Pluton in southern Japan appears as a red bulge (indicating dense rock) in the center of a new 3D visualization by The University of Texas at Austin. The pluton is large enough to interfere with the nearby Nankai subduction zone and the region’s earthquakes. Credit: Adrien Arnulf

Big data imaging shows rock’s big role in channeling earthquakes in...

Minerals are visible in rock samples from the coast of Oman. Scientists said these rocks may reveal new information about subduction, an important tectonic process on Earth. Credit: Joshua Garber / Penn State.

Mineral dating reveals new clues about important tectonic process

A magnitude 8.2 earthquake was “hidden” within a magnitude 7.5 earthquake in 2021, sending a mysterious tsunami around the world, according to a new study in Geophysical Research Letters. Credit: Zhe Jia and AGU

Hidden magnitude-8.2 earthquake source of mysterious 2021 global tsunami

A series of earthquakes and aftershocks shook the Ridgecrest area in Southern California in 2019. Distributed acoustic sensing (DAS) using fiber-optic cables enables high-resolution subsurface imaging, which can explain the observed site amplification of earthquake shaking. Credit: Yang et al., 2022

Fiber-optic cables can produce high-resolution underground maps

The edges of Earth’s tectonic plates, centered over the Pacific Ocean. Colors indicate whether plates are scraping past (yellow), diving under (green), or pulling away (red) from one another. Study site near New Zealand marks the location of a newly forming subduction zone. Credit: Brandon Shuck/University of Texas Institute for Geophysics

How does a major subduction zone get started? It may begin...

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