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2307501 Basin analysis
Basins associated with strike-slip deformation
Sukonmeth Jitmahantakul
WEEK 5
Course schedule / 2016
Week
Date
1
9 Aug
Introduction to sedimentary basins
2
16 Aug
The physical state of the lithosphere
-
23 Aug
No class
3
30 Aug
Basins due to lithospheric stretching
4
6 Sep
Basins due to flexure
5
13 Sep
Basins associated with strike-slip deformation
6&7
20 Sep
Analogue modelling of basins / Basin development in Thailand
8
27 Sep
Mid-term exam 30%
9
4 Oct
Effects of mantle dynamics
10
11 Oct
The sediment routing system
11
18 Oct
Basin stratigraphy
12
25 Oct
Subsidence history
13
1 Nov
Thermal history
14
8 Nov
Building blocks of the petroleum play
15
15 Nov
Clastic and unconventional plays
16
22 Nov
Presentation 10% Report 20%
17
29 Nov
Final exam 40%
2307501 Basin analysis
Topic / exam
Foundations
Mechanics
Sedimentary basin-fill
Application
Knowledge sharing
Textbooks
2307501 Basin analysis
Week 5 - Outline
Strike-slip deformation
Tectonic settings of strike-slip faults
Classification of strike-slip faults
Basic observations
Structural pattern of strike-slip fault systems
Basins in strike-slip zones
2307501 Basin analysis
Strike-slip deformation
Strike-slip deformation occurs where principally lateral movement takes place
between adjacent crustal or lithospheric blocks.
In pure strike-slip, the displacement is purely horizontal, so there is no strain in
the vertical dimension.
The vertical stress in strike-slip faulting is the vertical lithostatic stress σyy = ρgy.
The vertical stress is always the intermediate stress.
In reality, movement in strike-slip zones is rarely purely lateral, and
displacements are commonly oblique, that is, involving a certain amount of
normal or reverse dip-slip movement.
2307501 Basin analysis
Five major active strike-slip faults
Map credit: Dr. Ian Watkinson
Strike-slip fault according to plate tectonic setting
From Allen and Allen (2013)
Tectonic settings of strike-slip faults and related strike-slip basins
From Noda (2013)
Classification of strike-slip faults
1 Interplate ‘transforms’ (deep-seated, delimiting plate)
1.1 Ridge transform faults Displace segments of oceanic crust with similar spreading vectors
e.g. Romanche fracture zone (Atlantic Ocean)
1.2 Boundary transform faults Separate different plates parallel to the plate boundary
e.g. San Andreas (California), Alpine Fault (New Zealand), Central Range Fault Zone (offshore Trinidad)
1.3 Trench-linked strike-slip faults Accommodate horizontal component of oblique subduction
e.g. Atacama Fault (Chile), Median Tectonic Line (Japan)
2 Intraplate ‘transcurrent’ faults (confined to crust)
2.1 Indent-linked strike-slip faults Bound continental blocks in collision zones
e.g. North Anatolian Fault (Turkey), East Anatolian Fault (Turkey), Altyn Tagh Fault (Mongolia-China), Kunlun Fault (Tibet),
Red River Fault (SE Asia)
2.2 Intracontinental strike-slip faults Separate allochthons of different tectonic styles
e.g. Garlock Fault (California)
2.3 Tear faults Accommodate different displacement within a given allochthon or between the
allochthon and adjacent structural units
e.g. Asiak fold-thrust belt (Canada)
2.4 Transfer faults Linking overstepping or en echelon strike-slip faults
e.g. Southern and Northern Diagonal faults (eastern Sinai, Israel)
From Sylvester (1988), Woodcock (1986)
Basins in strike-slip zones
A number of different types of basins
form in strike-slip zones, called ‘pullapart basins’ , ‘strike-slip basins’ ,
‘rhombochasms’ , ‘wrench grabens’
and ‘rhomb grabens’.
Allen and Allen (2013) identify two
broad types of strike-slip basin in
terms of thermal and subsidence
history:
(a) strike-slip basins that are relatively
thin-skinned; they can be regarded as
‘cold’ or hypothermal basins; and
(b) strike-slip basins with mantle
involvement; these can be thought of
as ‘hot’ or hyperthermal basins.
2307501 Basin analysis
From Allen and Allen (2013)
Modern
examples of
trench-linked
strike-slip
faults
(A) The Median Tectonic Line (MTL)
active fault system in southwestern
Japan, related to oblique subduction of
the Philippine Sea Plate (PS) along the
Nankai Trough (NT).
(B) The Great Sumatra Fault system
(GSF) along the Java–Sumatra Trench
(JST).
(C) Strike-slip faults in Alaska. Fault
names: DF, Denali; BRF, Boarder
Ranges; CSEF, Chugach St. Elias; FF,
Fairweather; TF, Transition.
(D) The Philippine Fault system (PF).
Plate names: AM, Amur; OK, Okhotsk; PS, Philippine Sea;
AU, Australian; SU, Sundaland; NA, North American;
PA, Pacific; YMC, Yukutat microcontinent.
From Noda (2013)
Indent-linked strike-slip fault systems
(A) North Anatolian Fault (NAF) caused by the
collision of the Arabian Plate (AR) with the
Eurasian Plate (EU).
(B) The Red River Fault (RRF) zone, caused by
the collision of the Indian Plate (IP) with the
Eurasian Plate.
EAF, East Anatolian Fault; NEAF, Northeast Anatolian Fault;
CF, Chalderan Fault; TF, Tabriz Fault; DSF, Dead Sea Fault;
BZFTB, Bitlis–Zagros Fold and Thrust Belt; BS, Black Sea;
MTS, Mediterranean Sea; MS, Marmara Sea; AS, Aegean Sea.
SCB, South China Block; SB, Songpan Block;
CB, Chuandian Block; ICB, Indochina Block; SF, Sagaing Fault;
JF, Jiali Fault; XXF, Xianshuihe–Xiaojiang Fault;
LSF, Longmen Shan Fault.
Plate names: EU, Eurasian; AR, Arabian; NU, Nubia (Africa); AT, Anatolian; SU, Sundaland; BU, Burma; YZ, Yangtze.
From Noda (2013)
Plate-boundary transform fault systems
Alpine Fault (AF)
New Zealand
San Andreas Fault systems (SAF)
North America
Dead Sea Fault systems
From Noda (2013)
Observations
Strike-slip zones are characterised by extreme structural complexity.
Individual strike-slip faults are generally linear or curvilinear in plan view, steep
(sub-vertical) in section, and penetrate to considerable depths, perhaps
decoupling crustal blocks at the base of the seismogenic crust (that is, at 10–15
km).
In contrast to regions of pure extension or contraction, strike-slip zones possess
prominent en echelon faults and folds, and faults with normal and reverse slip
commonly coexist.
The vergence direction of folds and the mass transport indicators from thrusts
associated with transpression are distinctively poorly clustered or apparently
random.
2307501 Basin analysis
Seismicity in major strike-slip tectonics
In California, the relative velocity between the
Pacific and North American plates is 47 mm yr−1.
Much of this displacement is taken up on the
right-lateral (dextral) San Andreas Fault.
Much of the present-day seismicity in the San
Andreas system originates from faults oblique to
the main fault zone.
These oblique faults define crustal blocks that are
rotating about a vertical axis.
Seismicity dies out below about 15 km, indicating
the brittle–ductile transition.
Focal mechanism solutions in strike-slip zones
are commonly highly variable, with mixtures of
strike-slip, extension and compression, reflecting
the complexities of deformation within a zone of
overall strike-slip deformation.
The San Andreas system, California
From Allen and Allen (2013)
Seismicity in major strike-slip tectonics
Seismicity in major strike-slip tectonics
Arakan fault zone
Sagaing fault
West
East
33
70
150
Depth (km)
Earthquake M6.8
(24 Aug 2016)
100 km
Block rotation by strike-slip faulting
Paleomagnetic studies support the idea that crustal blocks commonly undergo rotations about vertical axes.
(a) Fracture and rotation of a feldspar crystal along cleavage planes in a ductile matrix.
(b) Rotation of a hard surface soil layer as a result of the Imperial Valley earthquake of 1979. The ruled lines
are the evenly spaced furrows of a ploughed field.
(c) Rotating blocks defined by secondary cross-faults between an overlapping right step from the Coyote
Creek Fault to the San Jacinto Fault.
(d) Block model for rotation near the intersection of the San Jacinto and San Andreas faults inferred from
geology and seismicity.
From Allen and Allen (2013)
Surface heat flow
The heat flow measured above major
strike-slip faults, such as those of the San
Andreas system, is not significantly
elevated compared to background values.
The fact that observed heat flows are not
significantly elevated suggests that major
strike-slip faults are relatively weak
structures set in a background of strong
upper crust.
Low heat flows also indicate that the
localised extension along strike-slip zones
does not in general involve significant
mantle upwelling.
From Allen and Allen (2013)
Geomorphic features
The accumulation of individual slip events over long
periods of time commonly results in a linear trough
along the fault zone.
Streams draining adjacent uplands and their
interfluves are commonly offset laterally,
demonstrating longterm strike-slip displacement.
Since alluvial fans accumulate downstream of the
range front, their apices may also be displaced
laterally, and stream channels on the fan surface may
thus become beheaded.
From Allen and Allen (2013)
San Andreas Fault Carrizo Plain, CA
From USGS
From USGS
Principal displacement zone (PDZ)
(a) Schematic diagram illustrating variations in
structural style along a strike-slip fault zone.
(b) Releasing bend and stepover geometries.
From Dooley & Schreurs (2012)
Fracture sets
associated with a
shear displacement
1. Synthetic strike-slip faults orientated at small
angles to the regional shear couple. These are
frequently termed Riedel (R) shears. The sense of
offset is the same as that of the PDZ.
2. Antithetic strike-slip faults orientated at high angles
to the regional shear couple. These are termed
conjugate Riedel shears or R′. The sense of offset
is opposite to that of the PDZ.
3. Secondary synthetic faults or P shears with a
sense of offset similar to that of the PDZ.
4. Tension fractures related to extension in the strain
ellipse.
5. Faults parallel to the PDZ and shear couple or the
Y shears of Bartlett et al. (1981).
From Allen and Allen (2013)
Greendale Fault surface rupture
The Mw 7.1 Darfield (Canterbury) earthquake of 4 September 2010 (NZST) Image from Quigley et al. (2010)
Flower (palm tree) structures
The offset pattern on strike-slip faults in crosssection can be exceedingly complex.
The sense of displacement may vary along one
fault from horizon to horizon, and within a flower
structure faults of opposite displacement occur
together.
Additionally, a given fault in one cross-section may
commonly switch in dip in another cross-section.
From Allen and Allen (2013)
Structural pattern of strike-slip fault systems
Convergent, divergent or simple strike-slip (parallel) kinematics
Magnitude of the displacement
Material properties of the rocks and sedimentary infills in the deforming zone
Configuration of pre-existing structures giving a geological fabric
2307501 Basin analysis
Role of oversteps
An overstep or stepover is a structural discontinuity
between two approximately parallel overlapping or
underlapping faults.
Oversteps are extremely important in determining the
location of regions of subsidence and uplift along a
strike-slip system.
There appear to be two basic types:
(a) Oversteps along the strike of faults, that is,
observed in plan view; faults are continuous in the
down-dip direction.
(b) Oversteps along the dip of faults, that is, observed
in cross-section; faults are otherwise continuous in
plan view.
From Allen and Allen (2013)
Basins in strike-slip zones
A more detailed breakdown of basins in strike-slip zones on the basis of the
kinematic setting and geometry of bounding faults has also been proposed.
Fault-bend basins commonly develop at bends in the main strike-slip fault
where localised extension takes place (i.e. Ridge Basin, Vienna Basin)
Overstep basins form between the ends of two sub-parallel strike-slip fault
segments, which may merge at depth into one single master fault (i.e. Dead Sea
Basin).
Transrotational basins form as triangular gaps between crustal blocks
undergoing rotation about a sub-vertical axis (i.e. Los Angeles Basin).
Transpressional basins are elongate depressions parallel to the regional strike
of folds and faults in zones of oblique convergence. These basins subside
primarily by flexure caused by the supracrustal loads of tectonically shortened
regions along the strike-slip zone (i.e. Ventura Basin).
2307501 Basin analysis
Strike-slip basins at plate convergent margins
From Noda (2013)
Modern and ancient* examples of strike-slip basins
From Noda (2013)
Geometric properties of pull-apart basins
Plot of pull-apart basin width-length (displacement) relationship
From Noda (2013)
When viewed in two dimensions, there is a wellestablished relationship between length and width of
pull-apart basins.
Pull-apart basins have an aspect ratio (length to width) of
approximately 3 : 1.
The acute angle between the main strike-slip fault and
the basin-bounding faults of the pull-apart basin is
commonly 30°.
Basin depth depends on the amount of stretching
associated with strike-slip displacement.
Turkish pull-apart basins
From Allen and Allen (2013)
Typical geometry of termination areas of strike-slip faults
(A) If the block collides with a rigid continental crust, it shortens and is uplifted, accompanied by thrusts. At the
opposite side to the uplift, upper crust is mechanically pulled away, leading to subsidence.
(B) If the block extrudes with a rotational component into a weak oceanic crust (a transtensional setting), a
sedimentary basin forms at the end of the strike-slip fault. Examples include the Yinggehai Basin, which is
related to the extrusion of the Indochina Block, and the Gulf of California, which is related to the transtensional
movement of the Baja California Peninsula.
(C) The strike-slip fault diffuses its displacement through splayed extensional normal faults at its end. An
example is the Cerdanya clastic basin formed by late Miocene normal faulting at the termination of the La Tet
strike-slip fault, Spain
From Noda (2013)
Kinematic models for pull-apart basins
1. Overlap of side-stepping faults
2. Slip on divergent fault segments
3. Nucleation on en echelon
fractures or Riedel shears
4. Coalescence of adjacent pull-apart
basins into larger system
5. Transform-normal extension
From Allen and Allen (2013)
Continuum model of
pull-apart development
(a) Pull-apart begins life on a releasing fault bend. The
size of the bend controls the pull-apart basin width.
(b) Spindle-shaped basin.
Continued offset produces lazy S-shaped basin (c),
then a rhomb-shaped basin (d), then, finally, a long,
elongate trough floored with oceanic crust (e).
Most pull-aparts do not reach the stage represented
by (e); instead they tend to be terminated after the
basin length has reached about three times the
original width of the releasing bend (or fault
separation).
From Allen and Allen (2013)
Fault-bend basin: The Ridge Basin
(A) Simplified geological map showing
formations in the Ridge Basin.
(B) Conceptual basin-filling process
for the Ridge Basin.
Abbreviations:
FMT, Frazier Mountain Thrusts; BMF, Bear
Mountain Fault; CF, Canton Fault.
(C) Cross-sectional profiles showing
continuous axial sediment supply and
migration of sediments with relatively
fixed depocenters.
From Noda (2013)
Fault-bend basin: The Ridge Basin
(a) General tectonic and depositional setting for the Ridge Basin
as a pull-apart on the releasing bend of the San Gabriel Fault.
(b) Generalised cross-section showing the sedimentary facies and
principal faults.
The fine-grained lacustrine depocentres (Peace Valley) and
landslide/debris flow breccias (Violin Breccia) occur close to the
San Gabriel Fault zone
From Allen and Allen (2013)
Stepover basin: The Dead Sea Basin
The Dead Sea Basin developed in a transtensional domain of the Dead Sea Fault system.
On the northern side of the basin, the Lebanon and Anti-Lebanon ranges were uplifted in a transpressional
domain.
Abbreviations: AmF, Amaziyahu Fault; ArF, Arava Fault; WIF, Western Intrabasinal Fault; EBF, Eastern Boundary Fault; WBF, Western Boundary Fault; MS,
Mount Sedom; LD, Lisan Peninsula; LR, Lebanon Range; ALR, Anti-Lebanon Range; JR, Jordan River; SG, Sea of Galilee [69]; HV, Hula Valley [70]. Plate
names: AR, Arabian; NU, Nubian (African).
From Noda (2013)
Pull-apart basins in the Dead Sea Fault system
(a) Digital elevation model showing
topography and main faults.
The Dead Sea pull-apart basin in the
north (b) is pure strike-slip, whereas
the Gulf of Elat (Aqaba) in the south
(c) is transtensional with α = 5°
From Allen and Allen (2013)
Pull-apart basins in the Dead Sea Fault system
From Allen and Allen (2013)
Fault-termination basin: The Yinggehai Basin
Geological setting of the Red River Fault zone (RRFZ) and the Yinggehai Basin. The RRFZ was originally a
left-lateral strike-slip fault caused by the southeastern extrusion of the Indochina Block. The sense of
displacement changed to right-lateral in response to the southeastward extrusion of the South China Block.
Abbreviations: SMF, Song Ma Fault; HD, Hanoi Depression; GT, Gulf of Tonkin; YB, Yinggehai Basin; MB, Malay Basin; PB, Pattani Basin.
From Noda (2013)
Transpressional basin: The Aceh Basin
Detailed bathymetry around the Aceh Basin.
Red and yellow lines are strike-slip faults and
axes of anticlines
Physiographic map of the Sumatra region. Purple lines are strike-slip faults. The Weh Basin and Alas Valley
graben are considered to be stepover pull-apart basins
Abbreviations: GSF, Great Sumatra Fault; AF, Aceh Fault; SF, Simeulue Fault; WAF, West Andaman Fault; AB, Aceh Basin; TR, Tuba
Ridge; TB, Tuba Basin; SM, Simeulue Basin; WB, Weh Basin; BM, Barisan Mountain Range; AVG, Alas Valley Graben; OAH, outer-arc
high; ST, Sumatra Trench; AS, Andaman Sea.
From Noda (2013)
Transpressional basin: The Aceh Basin
Detailed bathymetry around the Aceh Basin.
Red and yellow lines are strike-slip faults and
axes of anticlines
Cross-sectional profiles of the Aceh Basin. The uppermost seismic unit 4 was deposited predominantly in the
northern part of the basin, suggesting a northward migration of the depocenter.
Abbreviations: GSF, Great Sumatra Fault; AF, Aceh Fault; SF, Simeulue Fault; WAF, West Andaman Fault; AB, Aceh Basin; TR, Tuba
Ridge; TB, Tuba Basin; SM, Simeulue Basin; WB, Weh Basin; BM, Barisan Mountain Range; AVG, Alas Valley Graben; OAH, outer-arc
high; ST, Sumatra Trench; AS, Andaman Sea.
From Noda (2013)
Strike-slip deformation and pull-apart basins
in obliquely convergent orogens
Diachronous eastwards movement of the Caribbean plate, with numbers showing the
locations of the leading edge, from Late Cretaceous (1) at 80 Ma to Recent (7) at 0 Ma,
from Escalona & Mann (2011)
From Allen and Allen (2013)
Conceptual models for depocenter migration and
axial sediment supply in fault-bend basins
(A) Progressive right-lateral migration of paired
bends on the foot-wall generates compressional
uplift and extensional depression on the
hanging-wall.
Sediments are always supplied from the same
direction along the long-axis of the basin.
(B) Depocenter fixes along the releasing bend
result from the right-lateral migration of
sediments deposited on the footwall.
A transpressional component would be required
to generate the sediment source, and en
échelon folds may form along the master faults.
Both models generate deposits with axial
sediments whose thicknesses are greater than
the burial depths.
From Noda (2013)
Week 5 - Outline
Strike-slip deformation
Tectonic settings of strike-slip faults
Classification of strike-slip faults
Basic observations
Structural pattern of strike-slip fault systems
Basins in strike-slip zones
2307501 Basin analysis