Tectonics of Strike-Slip Restraining and Releasing Bends (Geological Society Special Publication no 290)

478 Pages·2008·21.65 MB·English

by  W. D. Cunningham & P. Mann

Tectonics of Strike-Slip Restraining and Releasing
Bends
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CUNNINGHAM,W.D.&MANN,P.(eds)2007.TectonicsofStrike-SlipRestrainingandReleasingBends.
GeologicalSociety,London,SpecialPublications,290.
WALDRON,J.W.F,ROSELLI,C.&JOHNSTON,S.K.2007.TranspressionalstructuresonaLatePalaeozoic
intracontinental transform fault, Canadian Appalachians. In: CUNNINGHAM, W. D. & MANN, P. (eds)
Tectonics of Strike-Slip Restraining and Releasing Bends. Geological Society, London, Special
Publications,290,367–385.
GEOLOGICAL SOCIETY SPECIAL PUBLICATION NO.290
Tectonics of Strike-Slip Restraining and Releasing
Bends
EDITED BY
W. D. CUNNINGHAM
University of Leicester, UK
and
P. MANN
University of Texas at Austin, USA
2007
Published by
The Geological Society
London
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Contents
CUNNINGHAM,W.D.&MANN,P.Tectonicsofstrike-sliprestrainingandreleasingbends 1
MANN,P.Globalcatalogue,classificationandtectonicoriginsofrestraining-andreleasingbends 13
onactiveandancientstrike-slipfaultsystems
Bends,sedimentarybasinsandearthquakehazards
LEGG,M.R.,GOLDFINGER,C.,KAMERLING,M.J.,CHAYTOR,J.D.&EINSTEIN,D.E. 143
Morphology,structureandevolutionofCaliforniaContinentalBorderlandrestrainingbends
WAKABAYASHI,J.Stepoversthatmigratewithrespecttoaffecteddeposits:fieldcharacteristics 169
andspeculationonsomedetailsoftheirevolution
GRAYMER,R.W.,LANGENHEIM,V.E.,SIMPSON,R.W.,JACHENS,R.C.&PONCE,D.A. 189
Relativelysimplethrough-goingfaultplanesatlarge-earthquakedepthmaybeconcealedbythe
surfacecomplexityofstrike-slipfaults
BOHOYO,F.,GALINDO-ZALDI´VAR,J.,JABALOY,A.,MALDONADO,A.,RODRI´GUEZ- 203
FERNA´NDEZ,J.,SCHREIDER,A.&SURIN˜ACH,E.Extensionaldeformationanddevelopmentof
deepbasinsassociatedwiththesinistraltranscurrentfaultzoneoftheScotia–Antarcticplate
boundary
Restrainingbends,transpressionaldeformationandbasementcontrolsondevelopment
CUNNINGHAM,W.D.Structuralandtopographiccharacteristicsofrestrainingbendmountain 219
rangesoftheAltai,GobiAltaiandeasternmostTienShan
MANN,P.,DEMETS,C.&WIGGINS-GRANDISON,M.TowardabetterunderstandingoftheLate 239
Neogenestrike-sliprestrainingbendinJamaica:geodetic,geological,andseismicconstraints
SEYREK,A.,DEMI˙R,T.,PRINGLE,M.S.,YURTMEN,S.,WESTAWAY,R.W.C.,BECK,A.& 255
ROWBOTHAM,G.KinematicsoftheAmanosFault,southernTurkey,fromAr/Ardatingofoffset
Pleistocenebasaltflows:transpressionbetweentheAfricanandArabianplates
GOMEZ,F.,NEMER,T.,TABET,C.,KHAWLIE,M.,MEGHRAOUI,M.&BARAZANGI,M.Strain 285
partitioningofactivetranspressionwithintheLebaneserestrainingbendoftheDeadSeaFault
(LebanonandSWSyria)
SMITH,M.,CHANTRAPRASERT,S.,MORLEY,C.K.&CARTWRIGHT,I.Structuralgeometry 305
andtimingofdeformationintheChainatduplex,Thailand
MORLEY,C.K.,SMITH,M.,CARTER,A.,CHARUSIRI,P.&CHANTRAPRASERT,S.Evolution 325
ofdeformationstylesatamajorrestrainingbend,constraintsfromcoolinghistories,MaePing
faultzone,westernThailand
ZAMPIERI,D.&MASSIRONI,M.Evolutionofapoly-deformedrelayzonebetweenfault 351
segmentsintheeasternSouthernAlps,Italy
WALDRON,J.W.F.,ROSELLI,C.&JOHNSTON,S.K.TranspressionalstructuresonaLate 367
Palaeozoicintracontinentaltransformfault,CanadianAppalachians
Releasingbends,transtensionaldeformationandfluidflow
MOUSLOPOULOU,V.,LITTLE,T.A.,NICOL,A.&WALSH,J.J.Terminationsoflargestrike-slip 387
faults:analternativemodelfromNewZealand
FODOR,L.I.Segmentlinkageandthestateofstressintranstensionaltransferzones:field 417
examplesfromthePannonianBasin
vi CONTENTS
DEPAOLA,N.,HOLDSWORTH,R.E.,COLLETTINI,C.,MCCAFFREY,K.J.W.&BARCHI,M.R. 433
Thestructuralevolutionofdilationalstepoversinregionaltranstensionalzones
BERGER,B.R.The3Dfaultandveinarchitectureofstrike-slipreleasing-andrestrainingbends: 447
evidencefromvolcanic-centre-relatedmineraldeposits
Index 473
Tectonics of strike-slip restraining and releasing bends
W. D. CUNNINGHAM1 &P. MANN2
1Department of Geology, University of Leicester, Leicester LEI 7RH,
UK (e-mail: [email protected])
2Institute of Geophysics, Jackson Schoolof Geosciences, 10100 Burnet Road, R2200,Austin,
Texas 78758, USA (e-mail: [email protected])
One of the remarkable tectonic features of the accommodateextensionarereferredtoasreleasing
Earth’s crust is the widespread presence of long, bends (Fig. 1; Crowell 1974; Christie-Blick
approximately straight and geomorphically promi- & Biddle 1985). Double bends have bounding
nentstrike-slipfaultswhichareakinematicconse- strike-slipfaultswhichenterandlinkacrossthem,
quenceoflarge-scalemotionofplatesonasphere whereas single bends are essentially strike-slip
(Wilson1965).Strike-slipfaultsformincontinental fault-termination zones. Restraining and releasing
andoceanictransformplateboundaries;inintraplate bends are widespreadon the Earth’ssurface, from
settingsasacontinentalinteriorresponsetoaplate the scale ofmajor mountain ranges andrift basins
collision;andcanoccurastransferzonesconnecting to sub-outcrop-scale examples (Swanson 2005;
normal faults in rift systems and thrust faults in Mann this volume). Releasing bends have also
fold–thrustbelts(Woodcock1986; Sylvester1988; been documented along oceanic transforms con-
Yeatsetal.1997;Marshaketal.2003).Strike-slip necting spreading ridges (Garfunkel 1986;
faultsalsoarecommoninobliquelyconvergentsub- Pockalny 1997), and extra-terrestrial restraining
ductionsettingswhereinterplatestrainispartitioned bends have been interpreted to occur on Europa
intoarc-parallelstrike-slipzoneswithinthefore-arc, andVenus(Koenig&Aydin1998;Saridetal.2002).
arc or back-arc region (Beck 1983; Jarrard 1986; Strike-slip restraining and releasing bends are
Sieh&Natawidjaja2000). sitesoflocalizedtranspressionalandtranstensional
When strike-slip faults initiate in natural and deformation, respectively.Thus,bendsare charac-
experimental settings, they commonly consist of terized by oblique deformation that is ultimately
en e´chelon fault and fold segments (Cloos 1928; controlled by larger-scale relative plate motions
Riedel 1929; Tchalenko 1970; Wilcox et al. either acting on relatively straight, long interplate
1973). With increased strike-slip displacement, boundaries (Garfunkel 1981; Mann et al. 1983;
and independent of fault scale (Tchalenko 1970), Bilham & Williams 1985; Bilham & King 1989)
faultsegmentslink,andthelinkedareasalongthe or acting across more complex zones of intraplate
‘principal displacement zone’ may define alternat- deformation where faults tend to be shorter, less
ingareasoflocalizedconvergenceanddivergence continuous and more arcuate (Cunningham this
along the length of the strike-slip fault system volume). Within the bend, oblique deformation
(Fig. 1; Crowell 1974; Christie-Blick & Biddle may be accommodated by oblique-slip faulting or
1985;Gamond1987).Typically,divergentandcon- partitioned into variable components of strike-slip
vergent bends are defined as offset areas where and dip-slip fault displacements (Jones & Tanner
bounding strike-slip faults are continuously linked 1995; Dewey et al. 1998; Cowgill et al. 2004b;
and continuously curved across the offset, Gomez et al. this volume). As seen in deeply
whereas more rhomboidally shaped stepovers are eroded outcrop exposures or from subsurface geo-
definedaszonesofsliptransferbetweenoverstep- physical surveys, double restraining bends and
ping,butdistinctlyseparateandsubparallelstrike- releasing bends commonly define positive and
slip faults (Wilcox et al. 1973; Crowell 1974; negative flower structures respectively, and strike-
Aydin&Nur1982,1985).However,faultstepovers slip bends or ‘duplexes’ in plan view (Fig. 1;
may evolve into continuous fault bends as the Lowell 1972; Sylvester & Smith 1976; Christie-
bounding faults and connected splays propagate Blick&Biddle1985;Harding1985;Woodcock&
and link across the stepover (e.g. Zhang et al. Fisher 1986; Dooley et al. 1999), although con-
1989; McClay & Bonora 2001). Thus, the two siderable structural variation and complexity
terms ‘stepover’ and ‘fault bend’ are often occurs (Barka & Gulen 1989; May et al. 1993;
usedinterchangeably. Wood et al. 1994; Waldron 2004; Barnes et al.
Bends that accommodate local contraction are 2005; Decker et al. 2005; Parsons et al. 2005).
referred to as restraining bends, and those that Single bends commonly have horsetail splay fault
From:CUNNINGHAM,W.D.&MANN,P.(eds)TectonicsofStrike-SlipRestrainingandReleasingBends.
GeologicalSociety,London,SpecialPublications,290,1–12.
DOI:10.1144/SP290.1 0305-8719/07/$15.00#TheGeologicalSocietyofLondon2007.
2 W.D.CUNNINGHAM&P.MANN
Contractional horsetail splay
Transtensional Extensional
relay ramp strike-slip
duplex
Oblique deformation
Pull-apart boreoltg –e ntranspressional
Pfslotorwusciettirvuere Relebaesinndg PairPeadir beedn bde bnydpass RfsCaetruosiklnttretar-aisncliitpnio gdn ubapellnedx GNenatrlreo wre spturashin iunSpgh rabidrepgn edr estraining bend Ehoxrtesentsaioilnal
Double restraining bend Single restraining bend splay
Transtensional rift sDteilaptoiovnearl En echelon folds
Nfloewgeartive Contractional stepover
structure
Fig.1. Tectonicfeaturesassociatedwithstrike-sliprestrainingandreleasingbends.
geometries in plan view, with strike-slip displace- lowest topographic depressions, such as the Dead
ments terminally accommodated by oblique-slip Sea(tenBrinketal.1999),DeathValley(Christie-
and dip-slip faulting (McClay & Bonora 1997). Blick&Biddle1985)andsubmarinebasinsunder-
Adjacent restraining and releasing bends called lyingtheGulfofAqaba(Elat;Ben-Avraham1985),
‘paired bends’ by Mann (this volume) are com- theCaymantrough(Leroyetal.1996,AAPG)and
monlydescribedfromstrike-slipsystemsinalltec- theGulfofCalifornia(Persaudetal.2003).
tonic settings and may reflect a volumetric Restrainingandreleasingbendsalongbothcon-
balancing between crustal thickening and uplift at tinental and oceanic strike-slip faults may act as
restraining bends, and crustal thinning and basin barriers to earthquake propagation (King &
formation at releasing bends (Woodcock & Nabelek 1985; Sibson 1985; Barka & Kadinsky-
Fischer1986). Cade 1988) or conversely, they may provide
Restrainingbendsaresitesoftopographicuplift, nucleation sites for major earthquakes (e.g. Shaw
crustal shortening and exhumation of crystalline 2006). There are also documented cases of large
basement (Segall & Pollard 1980; Mann & fault bend earthquakes (M.7) having complex
Gordon 1996; McClay & Bonora 2001), whereas rupturemechanismswithmultiplefaultsbeingacti-
releasing bends are sites of subsidence, crustal vatedwithinthebend,aswellasmajorfaultsrup-
extension, significant basin sedimentation, high turing through the bend (Bayarsayhan et al. 1996;
fluid flow, and possible volcanism (Aydin & Nur Harris et al. 2002). Because the length of fault
1982;Mannetal.1983;Hempton&Dunne1984; segmentruptureisproportionaltoearthquakemag-
Dooley & McClay 1997). Restraining bends and nitude (Scholz 1982), identification of fault bends
releasingbendsarecommonlyelongate,lazy-S-or between parallel strike-slip fault segments that
Z-shaped features in plan view, and they may mayactasseismicpropagationbarriersisimportant
form the dominant topographic and structural in assessing the potential severity of future earth-
feature within a deforming region. With increased quakesinareasofactivestrike-slipfaulting.Docu-
strike-slip offset, S- and Z-shaped pull-apart menting three-dimensional fault connectivity and
basinsmayevolveintomorerhomboidallyshaped kinematics within an individual fault bend is
features(Mannetal.1983). important for assessing whether the bend may act
Restraining bends produce elongate, individual as a future earthquake propagation barrier
massifs with anomalously high topographic (Graymeretal.thisvolume).
elevations such as the Denali Range in Alaska In addition to earthquake hazards, tectonically
(Fitzgerald et al. 1993), the Lebanon and Anti- active fault bends have other societal relevance.
Lebanon ranges of the Middle East (Gomez et al. Restrainingbendsmay:
thisvolume),ortheCordilleraSeptentrionalonthe
islandofHispaniola(Mannetal.1984,2002).Releas- 1. exhume crystalline basement rocks that
ing bends produce pull-apart basins and fault- contain important mineral deposits (e.g.
bounded troughs that comprise some of Earth’s Pinheiro&Holdsworth1997);
TECTONICSOFSTRIKE-SLIPBENDS 3
2. hosthydrocarbonsintheirinteriorsandflank- Bonora 2001). Because fault bends typically form
ing basins (Christie-Blick & Biddle 1985; in mechanically heterogeneous crust, pre-existing
Escalona & Mann 2003; Decker et al. faults and basement fabrics may be reactivated
2005);and insteadofnewfaultsgenerated.Theorientationsof
3. form major topographic uplifts that provide a reactivatedolderstructuresareunlikelytobeideal
locally significant rain catchment area and foreitherpurestrike-sliporpuredip-slipmotions,
potential groundwater resources (Gobi Altai thus oblique-slip displacements on reactivated
and Altai restraining bends, Cunningham faults are typically important within fault bends,
etal.1996;Cunningham2005,thisvolume). andworkersshouldthereforebeawareoffieldcri-
teria that indicate fault reactivation (Holdsworth
The societal significance of releasing bends etal.1997).
includesthefollowing:
1. pull-apart basins form depressions containing
Strain magnitude and distribution
significant sedimentary accumulations that
mayhosthydrocarbons,metalliferousdeposits, Strike-slip displacements along master faults that
evaporites and other industrial minerals (e.g. enterafaultbendwillbepartiallyorwhollyaccom-
theViennaBasin,Hamilton& Johnson1999; modatedbydeformationwithinthebend(Segall&
Hinschetal.2005); Pollard1980).Thus,largedisplacementstrike-slip
2. releasingbendsmaybezonesofhighheatflow faultsarecapableofproducingthelargestrestrain-
and crustal dilation that can be exploited as ingandreleasingbends.However,smallrestraining
sources of geothermal energy, such as the and releasing bends may also exist along major
Coso geothermal area of California (Lees strike-slip faults, especially when early formed
2002) and the Cerro Prieto geothermal area bendsarebypassedasthesystemevolves(Bennett
ofMexico(Glowackaetal.1999);and et al. 2004; Mann et al. this volume), or when
3. releasing bends may create large valleys that faultbendsnucleatelateinthehistoryofastrike-slip
provide fertile agricultural land and flat-lying faultsystem(Sieh&Natawidjaja2000),orwhenthe
urbanized areas, such as the Imperial Valley releasing stepover and basin depocentre has pro-
of southern California, the Silicon Valley of gressively migrated along the master strike-slip
northern California, the Vienna Basin of system,insteadofmaintainingafixedpositionrela-
Austria, and the Dead Sea–Sea of Galilee tive to the adjacent sliding blocks (Wakabayashi
ValleyintheMiddleEast. etal.2004;thisvolume;Lazaretal.2006).Depend-
ingontheanglebetweenthemasterstrike-slipfault
andthefar-fielddisplacementdirection,thedegree
Origin and evolutionof strike-slip fault ofstrainpartitioningofobliquedeformationwithin
bends thebendintoseparatethrust,normalandstrike-slip
displacements will control bend evolution. Kin-
Factors that influence and control the origin and ematic partitioning of non-coaxial strike-slip and
progressivedevelopmentofrestrainingandreleas- coaxialstrainsiscommonwhenthefar-fielddispla-
ing bends are complex and numerous, but can be cementdirectionisstronglyoblique(,208)tothe
groupedintoseveralmajorresearchthemes. deformation zone boundary (Dewey et al. 1998).
In addition, three-dimensional strain in strike-slip
Fault geometry andreactivation settings typically involves vertical-axis rotations
(e.g.Jackson&Molnar1990).Thus,theprogressive
Theshape,topographyandinternalarchitectureofa evolutionofafaultbendmayinvolvelocalvertical
fault bend is fundamentally controlled by several axis rotations within the bend, and vertical axis
factors, including the orientation of the plate rotations in the larger region that the bend occurs
motion vector relative to the master strike-slip within (Luyendyk et al. 1980; Westaway 1995;
fault; the original width of the stepover; and Cowgill et al. 2004b). This may be indicated by
whether the bend is a strike-slip fault termination; changesinstriketrends,andcanbeprovenpalaeo-
a double bend along a single continuously linked magnetically (Luyendyk et al. 1985). Progressive
strike-slipfault;orastepoverwhereparallelstrike- vertical-axis rotations within a fault bend will
slip fault segments are offset and may or may not result in changing fault kinematics as the faults
overlap.Forexample,widestepoversmaycontain rotate relative to the external stress field.
fewer faults that bridge the gap between master Vertical-axisrotationsmaythusleadtofaultaban-
strike-slip faults, whereas narrow stepovers may donmentandpropagationofnewfaults.Inaddition,
have greater linkage between major faults within strain hardening processes may operate locally
the bend (Dooley & McClay 1997; McClay & within the bend and may influence whether old