© ICDP, the International Continental Scientific Drilling Program, 1996-2020

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Scientific Exploration of Induced SeisMicity and Stress (SEISMS)

global

new workshop-proposal: ICDP-2016/13
for the funding-period starting 2016-01-15
by Heather Savage, James D. Kirkpatrick, Emily E. Brodsky, William L. Ellsworth, Frédéric Cappa, Frédéric Cappa, Brett M. Carpenter, Xiaowei Chen, Yasuyuki Kano
Abstract
Earthquakes and associated phenomena such as tsunamis and landslides represent some of the world’s most significant hazards. However, many of the fundamental physical processes and conditions controlling earthquake occurrence remain poorly constrained. The Rangely experiment in the 1960s and 1970s demonstrated that injecting fluid into fault zones increases the tendency for faults to slip as predicted by the effective stress hypothesis. Building on the Rangely results, we propose an active experiment, where fluid injection into a previously-instrumented fault would cause moderate seismicity. Because of the small size of some earthquake signals, measurements with sufficient resolution to decipher the processes active at the source must be made at depth within a fault. Fault zone drilling is therefore the only way to probe the physical causes of earthquake slip and arrest. As earthquakes are impossible to predict, instrumenting a fault and then inducing an earthquake is a plausible way of capturing an earthquake within a network of instruments. This project could address many of the outstanding problems in earthquake science including: How do earthquakes nucleate? How do they propagate? Why do they arrest? Furthermore, a fluid-injection experiment would allow for better understanding of the problem of unwanted anthropogenic induced seismicity that is currently associated with petroleum, geothermal, and carbon sequestration activities by more clearly articulating what conditions are necessary and sufficient for inducing earthquakes. The undertaking of such an experiment requires years of careful thought and input from earthquake researchers, as well as the larger geoscience community. Here we propose to hold a workshop to discuss the scientific goals that could be met by such an experiment, how an experiment might be safely carried out, and the potential technical challenges that will need to be overcome. Usually ICDP workshops discuss scientific questions and chances of success for answering those questions with a borehole at a specific site. However, this proposal is slightly different since for such an innovative experiment, a combination of scientific and social factors need to be discussed before a specific site can be selected. Therefore, site selection will be a primary goal of this workshop.
Scientific Objectives
  • The goal of an active earthquake experiment is to better understand the earthquake process through unique instrumentation. Earthquakes occur at depth and are spatially and temporally unpredictable. Therefore, it is impossible to make direct measurements of how fault structure, stress, fluid pressure, and deformation control rupture before, during and after an earthquake. Such knowledge is key for pushing forward our ability to measure and comprehend precursory earthquake activity. Furthermore, better understanding of the earthquake process, especially including the role of fluids, would allow us to better control anthropogenic induced seismicity. The science objectives of the SEISMS workshop include establishing the direct earthquake signals we wish to measure, the drilling and instrumentation needed to make such measurements, experiment localities that would be most advantageous (both scientifically and societally), and site characterization needed before the experiment begins. We expect that the outcome of the workshop will include a detailed plan of the types of data, criteria for acceptable site locations, and technological advances that will be required for drilling and instrumenting a fault for an active experiment. The workshop will provide a roadmap for future investigations of earthquake processes through scientific drilling, both in a technical sense and to motivate future work, and will provide information for policy makers and the general public on topics such as seismic hazard and groundwater contamination due to permeability changes.
Keywords
Canada, Earthquake experiment, Fault zone drilling, ICDP-2016/13, Induced seismicity, North america, SEISMS, U.S.A.
Location
global: 0, 0

© ICDP, the International Continental Scientific Drilling Program, 1996-2020

www.icdp-online.org