Earthquake Rupturing in Fluid-Overpressured Crust: How Common?
详细信息 查看全文
- 作者：Richard H. Sibson (1)
- 刊名：Pure and Applied Geophysics
- 出版年：2014
- 出版时间：November 2014
- 年：2014
- 卷：171
- 期：11
- 页码：2867-2885
- 全文大小：870 KB
- 参考文献：1. Abers , G.A. (2005), / Seismic low- / velocity layer at the top of subducting slabs: observations, predictions, and systematics, Phys Earth Planet Int / 149, 7-9.
2. Anderson , E.M. (1905), / The dynamics of faulting, Trans Edin Geol Soc / 8, 387-02.
3. Antonioli, A., Piccinini, D., Chiaraluce, L. and Cocco , M. (2005), / Fluid flow and seismicity pattern: evidence from the 1997 Umbria- / Marche (central Italy) seismic sequence, Geophys Res Lett / 32, L10311, doi:10.1029/2004GL022256 .
4. Audet, P., Bostock, M.G., Christensen, N.I. and Peacock, S.M . (2009), / Seismic evidence for overpressured subducted ocean crust and megathrust fault sealing, Nature / 457, 76-8.
5. Baisch, S., Weidler, R., V?r?s, R, Wyborn, D. and de Graaf , L. (2006), / Induced seismicity during the stimulation of a geothermal HFR reservoir in the Cooper Basin, Australia, Bull Seism Soc Am / 96, 2242-256.
6. Becken, M., Ritter, O., Bedrosian, P.A. and Weckmann, U. (2011), / Correlation between deep fluids, tremor and creep along the central San Andreas fault, Nature / 480, 87-0.
7. Becken, M., Ritter, O., Park, S.K., Bedrosian, P.A., Weckmann, U. and Weber , M. (2008), / A deep crustal fluid channel into the San Andreas Fault system near Parkfield, California, Geophys J Int / 173, 718-32.
8. Bedrosian, P.A., Unsworth, M.J. and Egbert, G. (2002), / Magnetotelluric imaging of the creeping segment of the San Andreas Fault near Hollister, Geophys Res Lett / 29, 1-.
9. Bedrosian, P.A., Unsworth, M.J., Egbert, G.D. and Thurber, C.H. (2004), / Geophysical images of the creeping segment of the San Andreas fault: implications for the role of crustal fluids in the earthquake process, Tectonophysics / 385, 137-58.
10. Begbie, M.J. and Sibson , R.H. (2006), / Structural controls on the development of fault- / hosted scheelite- / gold mineralisation in Glenorchy, Northwest Otago, In, Christie, A. and Brathwaite, R. (eds.), / Mineral Deposits of New Zealand, Aust Inst Min Metall Mon / 25, 291-98.
11. Berry , F.A.F. (1973), / High fluid potentials in California Coast Ranges and their tectonic significance, AAPG Bulletin / 57, 1219-249.
12. Bibby, H.M., Caldwell, T.G., Davey, F.J. and Webb, T.H. (1995), / Geophysical evidence on the structure of the Taupo volcanic zone and its hydrothermal circulation, J Volc Geotherm Res / 68, 29-8.
13. Boncio , P. (2008), / Deep- / crust strike- / slip earthquake faulting in southern Italy aided by high fluid pressure: insights from rheological analysis, Geol Soc Lond Spec Publ / 299, 195-10.
14. Bonini , M. (2009), / Mud volcano eruptions and earthquakes in the Northern Apennines and Sicily, Italy, Tectonophysics / 474, 723-35.
15. Boullier, A.-M. and Robert , F. (1992), / Paleoseismic events recorded in Archean gold- / quartz vein networks, Val d’Or, Abitibi, Quebec, Canada, J Struct Geol / 14, 161-79.
16. Brace , W.F. (1960), / An extension of the Griffith theory of fracture to rocks, J Geophys Res / 65, 3477-480.
17. Brace , W.F. (1980), / Permeability of crystalline and argillaceous rocks, Int J Rock Mech Min Sci / 17, 241-51.
18. Byerlee , J.D. (1978), / Friction of rocks, Pure Appl Geophys / 116, 615-26.
19. Byerlee , J.D. (1993), / Model for episodic flow of high- / pressure water in fault zones before earthquakes, Geology / 21, 303-06.
20. Carpenter, B.M., Saffer, D.M. and Marone, C. (201 - 作者单位：Richard H. Sibson (1)
1. Department of Geology, University of Otago, P.O. Box 56, Dunedin, 9054, New Zealand - ISSN：1420-9136
文摘
Whether or not ruptures nucleate in fluid-overpressured crust (λ v?=?P f/σ v?>?0.4) is important because pore-fluids overpressured above hydrostatic lower fault frictional strength and may also vary through the earthquake cycle, acting as an independent variable affecting fault failure. Containment of fluid overpressure is precarious because pressure-dependent activation of faults and fractures allows drainage from overpressured portions of the crust. Discharge of fluids through activated fault-fracture permeability (fault-valve action) decreases overpressure so that subsequent failure depends on the cycling of both overpressure and frictional strength as well as tectonic stress. Geometric and mechanical considerations suggest that fluid overpressures are more likely to develop and be sustained in compressional/transpressional regimes as opposed to extensional/transtensional tectonic settings. On the basis of geophysical observations and force-balance analyses, subduction interface shear zones appear to be strongly but variably overpressured to near-lithostatic levels (λ v?>?0.9) over the full depth range of seismogenic megathrusts. Strong overpressuring at seismogenic depths is also documented in active fold-thrust belts and in areas of ongoing compressional inversion (e.g., northern Honshu) where inherited normal faults are reactivated as steep reverse faults, requiring near-lithostatic overpressures (λ v?→?.0) at depths of rupture initiation. Evidence for overpressuring around strike-slip faults is less clear but tends to be strongest in areas of transpression. In areas of extensional tectonics coincident with particularly high fluid discharge, there is some evidence of overpressuring concentrated towards the base of the seismogenic zone. In general, because of the limited resolution of geophysical techniques, it is easier to make the case for rupture propagation through overpressured crust than to make a definitive case for the direct involvement of overpressured fluids in rupture nucleation, though in some instances the circumstantial evidence is compelling. An unresolved related issue is the heterogeneity of overpressuring. Do the active fault zones themselves serve as fluid conduits that are locally overpressured with respect to the surrounding crust?