Rob Butler and Bill McCaffrey

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School of Earth and Environment University of
Leeds
Rob Butler and Bill McCaffrey
Outline STRUCT-STRAT The linked study of
deformation and depositional processes on
submarine slopes VIRTUAL SEISMIC ATLAS Knowledge
Transfer community initiative
Please pass comments back to butler_at_earth.leeds.a
c.uk mccaffrey_at_earth.leeds.ac.uk
http//earth.leeds.ac.uk/struc-strat/project-descr
iptions
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CONFIDENTIAL
A NEW RESEARCH PROGRAM STRUCT-STRAT The linked
study of deformation and depositional processes
on submarine slopes Rob Butler and Bill
McCaffrey with Martin Casey
Outline Background research at Leeds Outline
the scientific challenges Research
Program Pathfinder project Consortium
project Please pass comments back
to butler_at_earth.leeds.ac.uk mccaffrey_at_earth.leeds
.ac.uk
http//earth.leeds.ac.uk/struc-strat/project-descr
iptions
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Leeds Research Environment School of Earth
and Environment (SEE) One of the largest
geoscience groups in the UK. Long history of
academic and applied research Large
research-student community (40) Unique range
of industry-focused taught Masters courses
(Geophysics, Structural Geology, Engineering
Geology) Links to industry through consortium
research and spin-off companies (e.g. RDR)
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Leeds Research Environment key
groupings Structure Group 25 years structural
research in thrust belts, fold modelling etc.
Rob Butler, Martin Casey 6 PhD students MSc
Structural Geology with Geophysics Turbidites
Research Group (TRG) 12 years deep marine
clastics research Bill McCaffrey plus Rob Butler,
Jaco Baas, Jeff Peakall 8 PhD students
externals Rock Deformation Research (RDR)
Leading structural consultancy and applied
research group. Rob Knipe et al. Geophysics
Group Greg Houseman, Lykke Gemmer and
students. Numerical modeling of lithosphere
deformation Graham Stuart, Roger Clark et
al. Seismics MSc Geophysics Engineering Geology
Group etc Bill Murphy, Lucy Phillip
geotechnical studies, mass wasting. PhD and MSc
students linking with Civil Engineering groups
in Leeds external collaborator Scott Bowman,
President of PetroDynamics Development of PHIL
Stratigraphic Modelling package
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Leeds Research Environment investigators Outlin
es of the key research personnel in the
Struct-Strat project. Collectively we have
published over 150 research papers and
supervised gt40 research students. Rob Butler 25
years experience in the structural geometry and
evolution of thrust systems. Research has
developed to use high resolution stratigraphy to
investigate thrust-fold kinematics. Founding
director of MSc Structural Geology with
Geophysics. Bill McCaffrey Currently Director
of TRG. Over 15 years experience of deep marine
clastics and application of research to
industry. Martin Casey Co-investigator. 30
years experience of numerical structural geology,
particularly the use of finite element methods to
investigate deformations. Latterly has applied
soil mechanical approach to study deformation in
poorly consolidated sediments. External
collaborator Scott Bowman, President of
PetroDynamics
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A NEW RESEARCH PROGRAM STRUCT-STRAT The linked
study of deformation and depositional processes
on submarine slopes Rob Butler and Bill
McCaffrey with Martin Casey and Scott Bowman
OutlineUPDATE FROM POTENTIAL SPONSORS Outline
the scientific challenges Research
Program Pathfinder project Consortium project
http//earth.leeds.ac.uk/struc-strat
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UPDATE April 2005.

• Following discussions with possible sponsors we
  would like to draw out
• the following key themes
• Regional aspects a main driver here is to
  develop predictions of slope geometries in the
  past using these to predict possible sites of
  preferential sand accumulation. Beneficial for
  evaluating new prospects within known slope
  systems say when seismic data are poor and the
  system is subsequently deformed, or to examine
  consequences.
• Prospect scale Understanding links between
  fold-thrust development and nature of strat
  template may reduce risk in poorly imaged
  fore-limb areas.
• All scales feedbacks between rates of
  deformation and deposition could have large
  control on scales/timing/distribution of
  remobilisation.
• 4. Relationship with proprietary data. Data are
  needed the Pathfinder phase will need to
  establish nature of release/confidentiality of
  proprietary data within the consortium (and for
  publication).

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External controls on deep water clastic systems
The bathymetric influence on sediment deposition
e.g. TRG
Sediment patterns on slopes.
Multi-disciplinary project
geometry mechanics
Structural evolution
Why? Sed load drives/modifies slope
structure Sed style impacts wedge rheology Sed
architecture impacts on fault zone evolution
Consortium
Pathfinder
Establish workflows Focus deliverables Develop
partnerships
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OUTLINE OF RESEARCH CHALLENGES
Sedimentation and deformation on submarine slopes
Deposition/strat architectures
deformation styles
Scales The slope system (wedge
dynamics) Individual/groups of folds/thrusts Evolu
tion of fold-thrusts and fault zone architecture
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Slope grading processes
different stable (equilibrium) slopes
Shallow-detached MTCs
Deposition of turbidites
Whole prism creep
Controls 1 tectonic subsidence (thermal,
inversion etc) 2 sediment load (flexural
isostatic) 3 sediment input (timing, flux,
nature) 4 gravity spreading deformation
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Evolution of active submarine slopes sediment
load drives deformation, deformation impacts on
sediment distribution. Predict slope-dip and
rugosity create synthetic slopes input to
facies distribution models Probabilistic
prediction of the distribution and characteristic
architectures of sand bodies on deformed
submarine slopes.
before
after
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A 2-D finite element model of the system
geometry, populated with rheological properties.
Differential sediment loading
and associated surface slope modification A
diffusion-based sediment dispersal model, or
proprietary strat-modelling packages.
viscous
plastic
SEDIMENT WEDGE
e.g. salt
DETACHMENT
e.g. mud (rate-dependent)
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Strat model
deformation model
A key target is to investigate sensitivities in
both model elements to choices of time
increments, rheological properties, deposition
rules and the spatial resolution
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Multiple scenarios
Strat model PetroDynamics PHIL simulator.
deposition
flexural subsidence
compaction
Build wedge geometry
Impose a vector deformation field onto the strat
model, (which entails modification of the seabed
profile)
thermal subsidence
Finite element deformation model
Rheological properties
Refine wedge geometry
A key target is to investigate sensitivities in
both model elements to choices of time
increments, rheological properties, deposition
rules and the spatial resolution
Gravitational deformation
Multiple scenarios
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Sedimentation and deformation in deepwater
fold-thrust belts
Deposition/strat architectures
deformation styles
Scales The slope system (wedge
dynamics) Individual/groups of folds/thrusts Evolu
tion of fold-thrusts and fault zone architecture
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Styles of contraction at toe of slope?
thrusting
strain
Tectonic compaction.
folding
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Sedimentation during thrusting
Spaced anticlines, Little overlap
Little syn-thrusting sedimentation
Stacked with overlap
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Sediment loading conditions influences mechanics
of folding and faulting Structural activity
influences mini-basin evolution
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Stratigraphic controls on fault zone/forelimb
architecture
Sedimentation and deformation in deepwater
fold-thrust belts
Deposition/strat architectures
deformation styles
Scales The slope system (wedge
dynamics) Individual/groups of folds/thrusts Evolu
tion of fold-thrusts and fault zone architecture
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WNW
ESE
(Example case study Butler McCaffrey 2004, Mar
Petrol Geol)
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detached panel of sandstone
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(No Transcript)
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WNW
ESE
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Substrate carbonates
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ESE
WNW
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• Interaction between
• distributed deformation
• BUCKLING and
• thrust faulting

Mechanical behaviour of multilayer influences
thrust-fold zone evolution and hence final
architecture
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Sedimentation and deformation in deepwater
fold-thrust belts
Deposition/strat architectures
deformation styles
Scales The slope system (wedge
dynamics) Individual/groups of folds/thrusts Evolu
tion of fold-thrusts and fault zone architecture
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STRUCT STRAT ISSUES
modelling
observations
Large-scale slope evolution
Numerical modelling Database of
depositional/structural styles on modern slopes
Deep-water fold-thrust belts
Quantify structural architectural elements and
relate to deposition
Model sediment loading on fold-thrust arrays
Fold-fault zone evolution
Exceptional outcrop analogues - quantified
Numerical modelling of multilayers
Data provision
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External controls on deep water clastic systems
The bathymetric influence on sediment deposition
e.g. TRG
Sediment patterns on slopes.
Multi-disciplinary project
geometry mechanics
Structural evolution
Why? Sed load drives/modifies slope
structure Sed style impacts wedge rheology Sed
architecture impacts on fault zone evolution
Consortium
Pathfinder
Establish workflows Focus deliverables Develop
partnerships
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Program Pathfinder mid-late 2005 Main
consortium Sept 2006 - 2009
Costs Pathfinder 26k (50k) per sponsor
Early access to results Better alignment of
research results to sponsor needs Discounted
participation of consortium
Main Struct-Strat consortium (3 years) 30k per
sponsor/year Discounted to 27k for Pathfinder or
TRG Phase 5 sponsors Discounted to 24k for
sponsors of both of the above.
Priorities driven by pathfinder sponsors
activities depend on number of sponsors
http//earth.leeds.ac.uk/struc-strat/project-descr
iptions