Skip to main content
SpringerLink
Log in

Preseismic velocity changes observed from active source monitoring at the Parkfield SAFOD drill site

  • Letter
  • Published:

From Nature

View current issue Submit your manuscript

Abstract

Measuring stress changes within seismically active fault zones has been a long-sought goal of seismology. One approach is to exploit the stress dependence of seismic wave velocity, and we have investigated this in an active source cross-well experiment at the San Andreas Fault Observatory at Depth (SAFOD) drill site. Here we show that stress changes are indeed measurable using this technique. Over a two-month period, we observed an excellent anti-correlation between changes in the time required for a shear wave to travel through the rock along a fixed pathway (a few microseconds) and variations in barometric pressure. We also observed two large excursions in the travel-time data that are coincident with two earthquakes that are among those predicted to produce the largest coseismic stress changes at SAFOD. The two excursions started approximately 10 and 2 hours before the events, respectively, suggesting that they may be related to pre-rupture stress induced changes in crack properties, as observed in early laboratory studies1,2.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Figure 1: Map of the experiment site.
Figure 2: An example of the raw seismograms obtained from a horizontal component in the two periods.
Figure 3: Estimated delay times for the two periods.
Figure 4: A comparison of delay time variations with local seismicity and other deformation measurements.

Similar content being viewed by others

References

  1. Brace, W. F., Paulding, B. W. & Scholz, C. H. Dilatancy in the fracture of crystalline rocks. J. Geophys. Res. 71, 3939–3953 (1966)

    Article  ADS  Google Scholar 

  2. Scholz, C. H. Microfracturing and the inelastic deformation of rock I: Compression. J. Geophys. Res. 73, 1417–1432 (1968)

    Article  ADS  Google Scholar 

  3. Birch, F. The velocity of compressional waves in rocks to 10 kilobars, part 1. J. Geophys. Res. 65, 1083–1102 (1960)

    Article  ADS  Google Scholar 

  4. Birch, F. The velocity of compressional waves in rocks to 10 kilobars, part 2. J. Geophys. Res. 66, 2199–2224 (1961)

    Article  ADS  Google Scholar 

  5. Nur, A. & Simmons, G. The effect of saturation on velocity in low porosity rocks. Earth Planet. Sci. Lett. 7, 183–193 (1969)

    Article  ADS  Google Scholar 

  6. Walsh, J. B. The effect of cracks on the compressibility of rock. J. Geophys. Res. 70, 381–389 (1965)

    Article  ADS  Google Scholar 

  7. Nur, A. Effects of stress on velocity anisotropy in rocks with cracks. J. Geophys. Res. 76, 2022–2034 (1971)

    Article  ADS  Google Scholar 

  8. O’Connell, R. J. & Budiansky, B. Seismic velocities in dry and saturated cracked solids. J. Geophys. Res. 79, 5412–5426 (1974)

    Article  ADS  Google Scholar 

  9. De Fazio, T. L., Aki, K. & Alba, J. Solid earth tide and observed change in the in situ seismic velocity. J. Geophys. Res. 78, 1319–1322 (1973)

    Article  ADS  Google Scholar 

  10. Reasenberg, P. & Aki, K. A precise, continuous measurement of seismic velocity for monitoring in situ stress. J. Geophys. Res. 79, 399–406 (1974)

    Article  ADS  Google Scholar 

  11. Leary, P. C., Malin, P. E., Phinny, R. A., Brocher, T. & Voncolln, R. Systematic monitoring of millisecond traveltime variations near Palmdale, California. J. Geophys. Res. 84, 659–666 (1979)

    Article  ADS  Google Scholar 

  12. Yamamura, K. et al. Long-term observation of in situ seismic velocity and attenuation. J. Geophys. Res. 108 10.1029/2002JB002005 (2003)

  13. Silver, P. G., Daley, T. M., Niu, F. & Majer, E. L. Active source monitoring of cross-well seismic traveltime for stress-induced changes. Bull. Seismol. Soc. Am. 97, 281–293 (2007)

    Article  Google Scholar 

  14. Aki, K. & Richards, P. G. Quantitative Seismology (Freeman, New York, 1980)

    Google Scholar 

  15. Abercrombie, R. E. Earthquake source scaling relationships from -1 to 5 ML using seismograms recorded at 2.5-km depth. J. Geophys. Res. 100, 24015–24036 (1995)

    Article  ADS  Google Scholar 

  16. Rubin, A. M. & Gillard, D. Aftershock asymmetry/rupture directivity among central San Andreas fault microearthquakes. J. Geophys. Res. 105, 19095–19109 (2000)

    Article  ADS  Google Scholar 

  17. Segall, P., Jonsson, S. & Agustsson, K. When is the strain in the meter the same as the strain in the rock? Geophys. Res. Lett. 30 10.1029/2003GL017995 (2003)

  18. Unsworth, M., Bedrosian, P., Eisel, M., Egbert, G. & Siripunvaraporn, W. Along strike variations in the electrical structure of the San Andreas Fault at Parkfield, California. Geophys. Res. Lett. 27, 3021–3024 (2000)

    Article  ADS  Google Scholar 

  19. Cespedes, I., Huang, Y., Ophir, J. & Spratt, S. Methods for estimation of sub-sample time delays of digitized echo signals. Ultrason. Imaging 17, 142–171 (1995)

    Article  CAS  Google Scholar 

  20. De Jong, P. G. M., Arts, T., Hoeks, A. P. G. & Reneman, R. S. Determination of tissue motion velocity by correlation interpolation of pulsed ultrasonic echo signals. Ultrason. Imaging 12, 84–98 (1990)

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank the NSF funded SAFOD programme and those involved in providing the experiment site, R. Trautz for supplying the barometric pressure logger, M. Zumberge for providing the SAFOD strainmeter data, and D. Lippert and R. Haught for helping with field work. This work was supported by the NSF, Rice University, the Carnegie Institution of Washington, and Lawrence Berkeley National Laboratory of the US Department of Energy under contract DE-AC02-05CH11231.

Author information

Authors and Affiliations

  1. Department of Earth Science, MS-126, Rice University, 6100 Main Street, Houston, Texas 77005, USA,

    Fenglin Niu & Xin Cheng

  2. Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington DC 20015, USA,

    Paul G. Silver

  3. Earth Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA,

    Thomas M. Daley & Ernest L. Majer

Authors
  1. Fenglin Niu
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Paul G. Silver
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Thomas M. Daley
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Xin Cheng
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Ernest L. Majer
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Fenglin Niu.

PowerPoint slides

Rights and permissions

Reprints and permissions

About this article

Cite this article

Niu, F., Silver, P., Daley, T. et al. Preseismic velocity changes observed from active source monitoring at the Parkfield SAFOD drill site. Nature 454, 204–208 (2008). https://doi.org/10.1038/nature07111

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature07111

  • Springer Nature Limited

This article is cited by

Search

Navigation