Public Release: 

Reactivating fault slip with fluid injection

American Association for the Advancement of Science

This news release is available in Japanese.

Water injected into an inactive fault can cause aseismic slip along the fault -- movement without detectable earthquakes -- that may then indirectly lead to micro-earthquakes. That's the result from a controlled experiment by Yves Guglielmi and colleagues, who observed these events in real time after injecting fluid into a natural fault near an underground experimental facility in southeastern France. Researchers are intensely interested in this type of induced seismicity, especially with a rise in earthquakes caused by injections of wastewater from gas and oil exploration. The experiment by Guglielmi and colleagues offers a better look at how friction in fluid-filled faults contributes to slip along the fault. In this case, the injected water caused very slow, four-micrometers-per-second aseismic creep on the fault before transitioning to a faster, 10-micrometers-per-second seismic slip and a series of tiny earthquakes. As Francois Cornet notes in a related Perspective article, experiments like this could guide monitoring at injection sites by potentially keeping the injection flow rate at a level that maintains aseismic slip rather than triggering earthquakes.

###

Article #17: "Seismicity triggered by fluid injection-induced aseismic slip," by Y. Guglielmi; P. Henry at University of Aix-Marseille in Aix-en-Provence, France; Y. Guglielmi; P. Henry at CNRS in Aix-en-Provence, France; Y. Guglielmi; P. Henry at Institut de recherche pour le développement (IRD) in Aix-en-Provence, France; F. Cappa at University of Nice Sophia-Antipolis in Sophia-Antipolis, France; F. Cappa at CNRS in Sophia-Antipolis, France; F. Cappa at Institut de recherche pour le développement (IRD) in Sophia-Antipolis, France; F. Cappa at Côte d'Azur Observatory in Sophia-Antipolis, France; F. Cappa; J.-P. Avouac at California Institute of Technology in Pasadena, CA; D. Elsworth at Pennsylvania State University in University Park, PA; J.-P. Avouac at University of Cambridge in Cambridge, UK.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.