Book contents
- Frontmatter
- Contents
- Preface
- Acknowledgements
- 1 Introduction
- 2 Stress
- 3 Displacement and strain
- 4 Relation between stress and strain
- 5 Loading of brittle rocks to failure
- 6 Stress concentration
- 7 Theories of brittle failure of rocks
- 8 Extension fractures and shear fractures
- 9 Displacements and driving stresses of fractures
- 10 Toughness and fracture mechanics
- 11 Field analysis of extension fractures
- 12 Field analysis of faults
- 13 Evolution of extension fractures
- 14 Evolution of faults
- 15 Fluid transport in rocks – the basics
- 16 Fluid transport in faults
- 17 Fluid transport in hydrofractures
- Appendix A Units, dimensions, and prefixes
- Appendix B The Greek alphabet
- Appendix C Some mathematical and physical constants
- Appendix D Elastic constants
- Appendix E Properties of some crustal materials
- Index
- References
12 - Field analysis of faults
Published online by Cambridge University Press: 05 June 2012
Book contents
- Frontmatter
- Contents
- Preface
- Acknowledgements
- 1 Introduction
- 2 Stress
- 3 Displacement and strain
- 4 Relation between stress and strain
- 5 Loading of brittle rocks to failure
- 6 Stress concentration
- 7 Theories of brittle failure of rocks
- 8 Extension fractures and shear fractures
- 9 Displacements and driving stresses of fractures
- 10 Toughness and fracture mechanics
- 11 Field analysis of extension fractures
- 12 Field analysis of faults
- 13 Evolution of extension fractures
- 14 Evolution of faults
- 15 Fluid transport in rocks – the basics
- 16 Fluid transport in faults
- 17 Fluid transport in hydrofractures
- Appendix A Units, dimensions, and prefixes
- Appendix B The Greek alphabet
- Appendix C Some mathematical and physical constants
- Appendix D Elastic constants
- Appendix E Properties of some crustal materials
- Index
- References
Summary
Aims
Faults are measured in a very similar way as extension fractures. The main aims of this chapter are to:
Give field examples of typical faults.
Illustrate how the most important field measurements of faults are made.
Provide typical field data on dip-slip faults.
Provide field data on strike-slip faults.
Explain and discuss oblique-slip faults.
Dip-slip faults
Dip-slip faults are those where the displacement is parallel with the dip of the fault (Fig. 12.1). They include normal faults, reverse faults, and thrust faults (Figs. 8.3 and 8.8). The block above the fault plane is the hanging wall, the block below the fault plane the footwall (Fig. 12.1). Depending on the sense of slip and the fault dip, the main types of dip-slip faults are normal faults, reverse faults, thrusts, and overthrusts. More specifically, when the hanging wall moves down relative to the footwall, the fault is a normal fault. When the hanging wall moves up relative to the footwall, the fault is a reverse fault.
When the dip of a fault is less than 45° it is referred to as a low-angle fault. A low-angle normal fault is just referred to as such, but sometimes as a lag fault. However, low-angle reverse faults have special names. In general, if the dip of the reverse fault is less than 45° (for some the angle should be 30°), it is referred to as a thrust or a thrust fault.
Information
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- Rock Fractures in Geological Processes , pp. 354 - 372Publisher: Cambridge University PressPrint publication year: 2011
References
, 1984. Tectonic analysis of fault slip data sets. Journal of Geophysical Research, 89, 5835–5848.CrossRefGoogle Scholar
, 1990. Inversion of field data in fault tectonics to obtain the regional stress 3. A new rapid direct inversion method by analytical means. Geophysical Journal International, 103, 363–376.CrossRefGoogle Scholar
and , 2002. Behaviour of a rupture of the 21 June 2000 earthquake in South Iceland as revealed in asphalted car park. Journal of Structural Geology, 24, 1925–1936.CrossRefGoogle Scholar
, , and , 2000. Variable coupling across weak oceanic transform fault: Flateyjarskagi, Iceland. Terra Nova, 12, 97–101.CrossRefGoogle Scholar
, , , and , 2004. Co-seismic strike-slip fault displacement determined from push-up structures: the Selsund Fault case, South Iceland. Journal of Structural Geology, 26, 709–724.CrossRefGoogle Scholar
and , 2003. Mechanical behaviour of the Arnes and Hestfjall Faults of the June 2000 earthquakes in Southern Iceland: inferences from surface traces and tectonic model. Journal of Structural Geology, 25, 1507–1523.CrossRefGoogle Scholar
, , and , 1995. Fault growth by segment linkage: an explanation for scatterin maximum displacement and trace length data from the Canyonlands Grabens of SE Utah. Journal of Structural Geology, 17, 1319–1326.CrossRefGoogle Scholar
and , 1996. A modern regression approach to determining fault displacement-length scaling relationships. Journal of Structural Geology, 18, 147–152.CrossRefGoogle Scholar
and , 1992. Displacement-length scaling relationships for faults: Data synthesis and discussion. Journal of Structural Geology, 14, 1149–1156.CrossRefGoogle Scholar
, , and , 1993. Growth of normal faults: displacement-length scaling. Geology, 21, 1107–1110.2.3.CO;2>CrossRefGoogle Scholar
, 2007. Infrastructure and evolution of ocean-ridge discontinuities in Iceland. Journal of Geodynamics, 43, 6–29.CrossRefGoogle Scholar
and , 1975. Theoretical basis of some empirical relations in seismology. Bulletin of the Seismological Society of America, 65, 1073–1095.Google Scholar
, , , and , 1996. The shapes, major axis orientations and displacement pattern of fault surfaces. Journal of Structural Geology, 18, 235–248.CrossRefGoogle Scholar
, , , , and , 2003. Fault slip distribution of two June 2000 Mw 6.4 earthquakes in South Iceland estimated from joint inversion of InSAR and GPS measurements. Earth and Planetary Science Letters, 213, 487–502.CrossRefGoogle Scholar
and , 1987. Theoretical displacements and stresses near fractures in rock: with applications to faults, joints, veins, dikes and solution surfaces. In: (ed.), Fracture Mechanics of Rock. London: Academic Press, pp. 277–349.Google Scholar
and , 2005. Fundamentals of Structural Geology. Cambridge: Cambridge University Press.Google Scholar
, 1980. The mechanics of earthquake rupture. In: and (eds.), Physics of the Earth's Interior. Amsterdam: North Holland, pp. 555–649.Google Scholar
, 1985. Contoured patterns of the throw and hade of normal faults in the Coal Measures (Westphalian) of north-east Derbyshire. Proceedings of the Yorkshire Geological Society, 45, 147–161.CrossRefGoogle Scholar
, , , and , 1996. Geometry and scaling relations of a population of very small rift-related normal faults. Geology, 24, 683–686.2.3.CO;2>CrossRefGoogle Scholar
, 1990. The Mechanics of Earthquakes and Faulting. New York: Cambridge University Press.Google Scholar
, 1997. Displacement-length scaling for terrestrial and Martian faults: implications for Valles Marineris and shallow planetary grabens. Journal of Geophysical Research, 102, 12 009–12 015.CrossRefGoogle Scholar
, , and , 1996. Three-dimensional analysis of slip distributions on normal fault arrays with consequences for fault scaling. Journal of Structural Geology, 18, 295–309.CrossRefGoogle Scholar
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