Geoscience Reference
In-Depth Information
Table 7.5
Variation of depth and heat flow with age
for oceanic-lithosphere models
Heat flow (mW m
−2
)
Ocean depth (km)
0.345
t
1/2
480
t
-1/2
Half-space
2.6
+
0.350
t
1/2
,
473
t
-1/2
,
PSM
2.5
+
t
<
70 Ma
t
<
120 Ma
3.2e
-t/62.8
,
t
67e
t/62.8
,
6.4
−
>
70 Ma
33.5
+
t
>
120 Ma
0.365
t
1/2
,
510
t
-1/2
,
GDH1
2.6
+
t
<
20 Ma
t
<
55 Ma
2.47
-t/36
96e
-t/36
,
5.65
−
t
>
20 Ma
49
+
t
>
55 Ma
Figure 7.9.
Temperature
contours for three thermal
models of the oceanic
lithosphere. The
half-space model and the
plate models PSM
(Parsons, Sclater and
McKenzie) and GDH1
(global depth and heat)
are shown schematically
in Fig. 7.8. The GDH1
model has been
constrained so that it fits
both the oceanic depth
and heat-flow
measurements. Note that
GDH1 has a thinner plate
and higher temperatures
than the other models.
(After Stein and Stein,
Thermo-mechanical
evolution of oceanic
lithosphere: implications
for the subduction
process and deep
earthquakes (overview),
Geophysical Monograph
96, 1-17, 1996. Copyright
1996 American
Geophysical Union.
Modified by permission of
American Geophysical
Union.)
Half-space model
0
50
100
150
PSM plate model
0
50
100
150
GDH1 plate model
0
50
100
150
0 50 100 150
Age (Ma)
