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Tectonic heat flow modelling for basin maturation: method and applications
J.D. van Wees1,2,
R. Abdul-Fattah1, D. Bonte1,2,
H. Kombrink1, H. Verweij1, F. van Bergen, P. David
F. Beekman2, S. Cloetingh2
2Vrije Universiteit Amsterdam 1TNO
Content
• Definition of tectonic heat flow
• Workflow
• Added value of tectonic heat flow
• Tectonic models for the Netherlands
• West Netherlands Basin
• Netherlands Antilles
• Terschelling Basin
• Variscan Foreland evolution
shale k=1.7
sandstone k=2.5
salt k=6
Temperature (T) �
Dep
th (z) �
PD heat flow
q=60
q=80
q=40
q=30
Best fit
Heat flow (q) relates to the temperature
gradient. Present day (PD) Temperature data
(■) in wells can be directly related to (q)
kqdz
dT/=
tectonic heat flow is calculated from the temperature gradient in the top of the numerical kinematic models, which predict temperature effects of lithosphere deformation.
The 1D McKenzie Model (1978) is a classic for continental lithosphere extension (rifting)
crust
mantle
β =Li/Le
McKenzie model: lithosphere (Li) is instantaneously
thinned by factor β
Li
Le
Temperature (T) �
Dep
th (z) �
120 km
t=100My
t=0My
t=10My
t=30My
t=300My
1330 C
Tectonics:Lithosphere extension –
Predicted Mass surplus
Sediment record:Burial history-observed mass deficit
Tectonic Subsidence Model (δ δ δ δ = 1.47)
0
200
400
600
800
1000
1200
1400
1600
050100150200
Age [Ma]
Air
lo
ad
ed
te
cto
nic
su
bs
ide
nc
e [
m]
Observed
Model
For the McKenzie model a very simple analytical solution for the heat flow exist
(McKenzie, 1978)
Heat flow McKenzie Model (for various ββββ -values)
0
20
40
60
80
100
120
020406080100
Age[MA]
Heat
Flo
w [
mW
m-2
]
1.25
1.5
2
3
120 km
McKenzie heat flow
No Good:
•No crustal heat production•No sediment infill
Heat Flow Model, stretching (β=1.44)
Basement Heat Flow ( Heat production, ββββ=1.44)
45
50
55
60
65
70
75
050100150200
Age[Ma]
He
at
Flo
w [
mW
m-2
]
no sediments
sediments
synrift
Water filled
Sediment filled
Van Wees and Beekman, 2000 sed
crust
crust
mantle
1/β
Lith
osp
heric
thick
ness
Norm
al geo
therm
dT/dz
stretched
geo
therm
dT/dz
Tectonic
Subsidence
curve
Subsidence Inversion
– tectonic heat flow
Lithosphere
Parameters
Inverted
Tectonic model
TECTONICHEAT FLOW
Experimental design
SUB
SUBmin, PWDmin
SUBmax, PWDmax
SUBmax, PWDmin
SUBmin, PWDmax
PWDSample, interpolate from
Experimental nodes
Tectonic
Subsidence
curve
Subsidence Inversion
– tectonic heat flow
Lithosphere
Parameters
Inverted
Tectonic model
TECTONICHEAT FLOW
Uncertainty
Tectonic Subsidence
(PWD/erosion)
Heat flow Uncertainty
Uncertainty
Lithosphere
Parameters
(crust/lith)
Experimental designalternative
Inverted
Tectonic models
End-members
UNCERTAINTY TECTONIC
HEAT FLOW
MC sampling
Van Wees et al., 2008
Marine and Petroleum Geology
Calibration to Ro – PD temperatures – sensitivity analysis
Tectonic
Subsidence
curve
Subsidence Inversion
– tectonic heat flow
Lithosphere
Parameters
Inverted
Tectonic model
TECTONICHEAT FLOW
Uncertainty
Tectonic Subsidence
(PWD/erosion)
Heat flow Uncertainty
Uncertainty
Lithosphere
Parameters
(crust/lith)
Experimental designalternative
Inverted
Tectonic models
End-members
UNCERTAINTY TECTONIC
HEAT FLOW
MC sampling
UncertaintyMaturation
Maturation Uncertainty
Uncertainty
Sedimentary
Thermal properties
MC sampling
West Netherlands Basin – WAS-2
A priori Uncertainty
•Lithospheric thickness 90-130 km
•Erosion during Late Cretaceous Inversion 500-1500 m
•Porosity depth curves ���� sediment conductivity
Calibration
•Ro depth trend
•PD temperature gradient-
Subsidence NWB
0
200
400
600
800
1000
1200
050100150200250300350
Age [Ma]
Tecto
nic
su
bs [
m]
data
model
56
50
62
800+-300 m
EROSION
117+-10km
Lithosphere
thickness
1500
2000
2500
3000
3500
0.2 0.4 0.6 0.8 1 1.2 1.4
Ro [%]
De
pth
[m
]
was-32-
observed
Model
B
0
500
1000
1500
2000
2500
3000
3500
0 50 100 150Temperature[C]
De
pth
[m
]
was-32 -observed
Model
A
-0.875
Lithospheric thickness [m]
PD
Tem
per
ature
[C
]
Porosity-depth / subsidence 1.7 Ma [m]
PD
Tem
per
ature
[C
]
-0.215
Lithospheric Thickness
Porosity-depth relationship
Sensitivity
Tornado-plot
• 3D Basin Modeling: How to predict heat flow away from wells?
well
Best fit q=30
q=30?Use linear
extrapolation?
Added value of tectonic heat flow modeling
70&80s wells, NO HC
SHALLOW WATER, 28 mW
DEEP WATER , 38 mW
Possibly HC
SL
OW
FA
ST
Heat F
low
[mW
m-2
]
Age [Ma]
Netherlands Antilles
Van Wees et al., 2008 – Marine and Petroleum Geology
• Basin Modeling: How to find heat flow in the past
Age (Ma)
Hea
t F
low
�
Typical start:
Flat heat flow through timeusing the same as PD heat flow
Present day (PD) heat flow
Added value of tectonic heat flow modeling
• Basin Modeling: How to find better heat flow in the past
Modified to fit Ro
Age (Ma)
Hea
t F
low
�
Added value of tectonic heat flow modeling
Seismic tomography
demonstrates mantle plumes acting as heat advection channels
in the deep lithosphere
Goes et al., 2000
Ritter et al., 2001
Extension models – melts and underplates can arise from hot mantle (plumes) which result in accentuated heat advection and heat flow, relative to default extension
http://www.mantleplumes.org/
Crust
Mantle
Norm
al geo
therm
dT/dz
stretched
geo
therm
dT/dz
Underplate
β=1.5
Lith
osp
heric th
ickness
No
rmal g
eoth
erm
dT/dz
stretched
geo
therm
dT/dz
Crust
Mantle
dT/dz
Ho
t m
antl
e p
lum
eH
ot
man
tle
plu
me
stretched
geo
therm
uniform two-layered
δ=1.5
β=3
Van Wees et al., 2000- – Marine and Petroleum Geology Ziegler et al., 1998 - Tectonophysics
Sirt Basin
Abadi et al., 2008 –
AAPG Bulletin
0
500
1000
1500
020406080100
Age [Ma]
Tecto
nic
subs [m
]data
model
synrift
synrift
EAST SIRT- Agedabia WEST SIRT- Hun
0
500
1000
1500
020406080100Age [Ma]
Te
cto
nic
su
bs
[m
]
data
model
synrift
underplating
65
45
55
65
45
55
1500
2000
2500
3000
3500
4000
4500
5000
0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
Ro [%]
Dep
th [
m]
Agedabia-obs
Agedabia-model
HUN-obs
HUN-model
HUN
Agedabia
0
500
1000
1500
2000
2500
3000
3500
4000
4500
0 50 100 150
Temperature [C]
De
pth
[m
]
BHT 22/km
BHT 25/km
Van Wees et al., 2008 – Marine and Petroleum Geology
0
200
400
600
800
1000
1200
1400
0100200300
Age [Ma]
Tecto
nic
su
bsid
en
ce [m
]
observed
modelled
45
47
49
51
53
55
57
59
61
63
65
Basem
ent h
eat fl
ow
[m
W/m
2]
default heat
flowelevated
West Netherlands
Basinβ=1.5
Lith
osp
heric th
ickn
ess
No
rmal g
eoth
erm
dT/dz
stretched
geo
therm
dT/dz
Crust
Mantle
dT/dz
Ho
t m
antl
e p
lum
eH
ot
man
tle
plu
me
stretched
geo
therm
uniform two-layered
δ=1.5
β=3
Model building:Boundary conditions
-1600
-1400
-1200
-1000
-800
-600
-400
-200
0
-320 -270 -220 -170 -120 -70 -20
Age [Ma]
Te
cto
nic
su
bs
ide
nc
e [
m]
Tectonic Sub Tectonic Model
55
58
61
64
67
70
Basem
en
t h
eat
flo
w [
mW
/m2]
Calibrated Heat Flow
0.981.011.060.951.0411.111.140.89
-1600
-1400
-1200
-1000
-800
-600
-400
-200
0
-320 -270 -220 -170 -120 -70 -20
Age [Ma]
Te
cto
nic
su
bs
ide
nc
e [
m]
Tectonic Sub Tectonic Model
55
58
61
64
67
70
Basem
en
t h
eat
flo
w [
mW
/m2]
Calibrated Heat Flow
0.981.011.060.951.0411.111.140.89
Basal heat flow historyreconstructed from tectonicmodelling (Petroprob) (Rader Abdul Fattah
et al 2008)
33 heat flow maps
Willingshofer and Cloetingh, Tectonics 22, 2003
Ziegler et al., 1998
Carboniferous –Netherlands (1)
Kombrink et al., 2008 (Basin Research)
Carboniferous –Netherlands (2)
Carboniferous –Netherlands (4)
Conclusions
• Tectonic heat flow models aid in predicting heat flow for basin
modelling beyond well control
• Mature basins - Heat flow through time
• Frontier basins – spatial variability
• Tectonic heat flow models should include effects of crustal heat
production and sediment infill/erosion
• The Netherlands
• Average heat flow values today
• Considerable variation through time:
• Elevated at mantle plume/underplating phase
• Depressed during foreland formation
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