The process, called creep cavitation, involves fluid being pumped through pores in deformed rock in mid-crustal sheer zones, which are approximately 15 km below the Earth's surface.
The fluid transfer through the middle crust also plays a key role in tectonic plate movement and mantle degassing.
The discovery was made by examining one millimetre sized cubes of exposed rock in Alice Springs, which was deformed around 320 million years ago during a period of natural mountain formation.
The evidence is described in a paper published in the latest edition of Nature entitled Creep cavitation can establish a dynamic granular fluid pump in ductile shear zones.
One of the paper's author's CSIRO Exploration and Mining scientist Dr Rob Hough said that this was the first direct observation of fluids moving through the mid-crustal shear zone.
"We are seeing the direct evidence for one of the processes that got ore forming fluids moving up from the mantle to the shallow crust to form the ore deposits we mine today, it is also one of the mechanisms that can lead to earthquakes in the middle crust," Dr Hough said.
Research leader Dr Florian Fusseis, from the University of Western Australia, said that the discovery could provide valuable information in understanding how earthquakes are formed.
"While we understand reasonably well why earthquakes happen in general, due to stress build-up caused by motions of tectonic plates, the triggering of earthquakes is much more complex," Dr Fusseis said.
"To understand the 'where' and 'when' of earthquakes, the 'how' needs to be understood first. We know that earthquakes nucleate by failure on a small part of a shear zone."
Dr Fusseis said that while their sample did not record an earthquake it gave them an insight into the structures that could be very small and localized precursors of seismic failure planes.
The discovery was made possible through the use of high-resolution Synchrotron X-ray tomographic, scanning electron microscope observations at the nanoscale and advanced visualisation using iVEC in Western Australia.
The authors of the paper propose that the fluid movement, described as the granular fluid pump, is a self sustaining process where pores open and close allowing fluid and gas to be pumped out.
The paper was written by five authors from CSIRO Exploration and Mining working through the Minerals Down Under National Research Flagship, The School of Earth & Environmental Sciences, University of Western Australia and Advanced Photon Source, and Argonne National Laboratory, USA.
Three of the authors are with CSIRO: Prof Klaus Regenauer-Lieb who shares his time between CSIRO and the University of Western Australia and is also a WA Premiers Fellow; Dr Jie Liu and Dr Rob Hough.
The experiments at the Advanced Photon Source in Chicago were funded in part by the Australian Synchrotron Research Program.
CSIRO initiated the National Research Flagships to provide science-based solutions in response to Australia's major research challenges and opportunities. The nine Flagships form multidisciplinary teams with industry and the research community to deliver impact and benefits for Australia.
Image available at: http://www.scienceimage.csiro.au/mediarelease/mr09-100.htmlFurther Information:
Bob Chamberlain | EurekAlert!
Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute
Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine