Scientists have developed a method to estimate weakness in the Earth’s outer layers which will help explain and predict volcanic activity and earthquakes.
Published in the journal Science today, the research describes a new model of the Earth’s movement in the upper crust through to upper mantle (400km below the surface), allowing predictions at a much smaller scale than previously possible.
The research is a collaboration between researchers at the University of Illinois in the US and University of Adelaide in Australia.
Geodynamic modelling relies on knowing the ‘viscosity’ or resistance to changing shape of the Earth’s outer layers.
“Producing realistic models of these movements has been difficult because the small scale variations in viscosity are often poorly known,” says co-author Dr Derrick Hasterok, from the University of Adelaide’s School of Physical Sciences.
“In essence, we’ve developed a method to estimate small scale (between one and 10 kilometer) variations of viscosity within the upper 400 km of the Earth’s crust using surface-based electromagnetic imaging techniques.”
The resulting model allows the dramatic improvement of flow models which can be used to make predictions about the forces driving tectonic plate deformation and sources of potential seismic and volcanic activity.
“This method will aid our understanding of the processes happening that cause earthquakes and volcanic activity,” says Dr Hasterok. “We’ll be able to see why earthquakes and volcanoes have occurred in the past and look for places where this might potentially happen in the future.”
The method they have developed uses an electromagnetic imaging technique called magnetotellurics to estimate the electrical conductivity beneath the Earth's surface.
“The same factors which affect electrical conductivity ─ temperature, water content, and the presence of molten material (magma) ─ also affect the viscosity or strength. The hotter, wetter or more molten, the weaker the structure,” says lead author Dr Lijun Liu, from the University of Illinois.
“We’ve been able to look at processes operating beneath the Earth’s surface at a much smaller scale than previous geodynamic modelling.”
The researchers used data from a magnetotelluric survery of western United States to show their model works. Currently there is a continent-wide project mapping the Australian upper mantle using the same electromagnetic technique, and the researchers believe applying this data to their new model will bring improved understanding of volcanic and earthquake activity along the southeastern and eastern coast of Australia.
Dr Derrick Hasterok
School of Physical Sciences
University of Adelaide
Dr Lijun Liu
Assistant Professor in Geophysics
University of Illinois at Urbana-Champaign
Phone: +1 217 300 0378
Stagnation in the South Pacific Explains Natural CO2 Fluctuations
23.02.2018 | Carl von Ossietzky-Universität Oldenburg
First evidence of surprising ocean warming around Galápagos corals
22.02.2018 | University of Arizona
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy