Kaiser effect (material science)

From HandWiki - Reading time: 3 min

The Kaiser effect is a phenomenon observed in geology and material science that describes a pattern of acoustic emission (AE) or seismicity in a body of rock or other material subjected to repeated cycles of mechanical stress.

In material that exhibits an initial seismic response under a certain load, the Kaiser effect describes the absence of acoustic emission or seismic events until that load is exceeded. The Kaiser effect results from discontinuities (fractures) created in material during previous steps that do not move, expand, or propagate until the former stress is exceeded. [1] [2] [3]

Background

The Kaiser effect is named after Joseph Kaiser, who first studied this behavior in materials in the 1950s.[4] He discovered the phenomenon when he was studying AE response of metals, finding that the materials retain a "memory" of previously applied stresses.[5] Kaiser found that a stressed metal sample is zero if the applied stress is less than the previously applied maximum stress.[6] Similar effect was also found in rock samples deformed in the course of acoustic emission, particularly as a result of cyclic thermal loadings of carboniferous sandstone and mudstone samples.[7] The Kaiser effect became useful in estimating complete stress tensors based on a capacity to determine reliably the magnitudes of the preceding normal stresses applied to the specimen in various directions.[8]

Observed examples of the Kaiser effect

Borehole seismicity

Induced seismicity associated with fluid pumping in boreholes and wells often exhibits the Kaiser effect, whereby seismicity may be observed shortly following an initial fluid injection, but further seismicity is limited if the fluid flow remains at a constant pressure.[9] If the fluid pressure at the injection site is later increased, renewed seismicity may be observed due to the greater ease of fracturing caused by higher pore fluid pressure in the rock.

Volcanic systems

The Kaiser effect has also been observed in relation to recharge of magma chambers below active volcanic systems.[10]

See also

References

  1. "AE Sources". ndt-ed.org. http://www.ndt-ed.org/EducationResources/CommunityCollege/Other%20Methods/AE/AE_Theory-Sources.htm. Retrieved 2014-12-13. 
  2. Ciliberto, S.; Guarino, A.; Scorretti, R. (2001). "The effect of disorder on the fracture nucleation process". Physica D: Nonlinear Phenomena (springer) 158 (1–4): 83–104. doi:10.1016/S0167-2789(01)00306-2. Bibcode2001PhyD..158...83C. 
  3. Ettouney, M.M.; Alampalli, S. (2011). Infrastructure Health in Civil Engineering: Theory and Components. Taylor & Francis. p. 424. ISBN 9780849320408. https://books.google.com/books?id=3VePAhhi_OsC. Retrieved 2014-12-13. 
  4. "Error: no |title= specified when using {{Cite web}}". ndt.net. http://www.ndt.net/ndtaz/content.php?id=471. Retrieved 2014-12-13. 
  5. Hardy, Reginald Jr. (2005). Acoustic Emission/Microseismic Activity: Volume 1: Principles, Techniques and Geotechnical Applications. Lisse, The Netherlands: A.A. Balkema Publishers. pp. 248. ISBN 9058091937. 
  6. Tang, Chun'An; Hudson, John (2011). Rock Failure Mechanisms: Illustrated and Explained. Boca Raton, FL: CRC Press. pp. 129. ISBN 9780203841433. 
  7. Rossmanith, H. P. (2018). Mechanics of Jointed and Faulted Rock. Oxon: Routledge. pp. 58. ISBN 978-9054109556. 
  8. Brady, Barry H. G.; Brown, E. T. (2007-01-25). Rock Mechanics: For underground mining. Dordrecht: Springer Science & Business Media. pp. 156. ISBN 9781402020643. 
  9. Zang, A., Oye, V., Jousset, P., Deichmann, N., Gritto, R., McGarr, A., ... & Bruhn, D. (2014). Analysis of induced seismicity in geothermal reservoirs–An overview. Geothermics, 52, 6-21.
  10. Heimisson, E. R., Einarsson, P., Sigmundsson, F., & Brandsdóttir, B. (2015). Kilometer‐scale Kaiser effect identified in Krafla volcano, Iceland. Geophysical Research Letters, 42(19), 7958-7965.





Licensed under CC BY-SA 3.0 | Source: https://handwiki.org/wiki/Physics:Kaiser_effect_(material_science)
11 views | Status: cached on August 02 2024 07:43:48
↧ Download this article as ZWI file
Encyclosphere.org EncycloReader is supported by the EncyclosphereKSF