Page 338 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

for
321
maps
measured
older
Flow
on
Heat
values
used
and
often
5“!
typical
Tectonics
em=!°C-"
are
10°?
m~). Some
(HFU)
m=!
Wm7!°c"!
cal
km7!
0.05)°C
units
0.012)
W
:
50)°C
flow
to
to
5)
(0.005
to
x
heat
(0.01
(2to
4.2
(10
particular,
=
~
~
~
~
1076 calcm~?s~!
aT /dz
k
“
In
units.
are:
SI
=
Earth
to
HFU
that:
relate
and:
the
so
(1
#
held constant. m™? W 0.12) to (0.03 ~ q HFU to3) ( 1 = J FLOW HEAT AND TECTONICS of the region one from heat of transfer The convec- by enhanced is another to Earth lithospheric of movement facilitates convection the mantle; upper the within tion of oceanic flow heat overall the elevates generally transfer Lateral (Fig. 2.10). plates features shallow makes
is the in ; Units calem=!°Co! oe km“! s Peng
thermal conductivity (k) remains constant. measured at different depths (0T/dz). Combining with k(dT/dz). = q is calculated as other units found to (SI) Equivalent 1073 X 2.39 ae 10° _ X 29
of geothermal gradient; the (un) ydeg =z a) Temperatures (T,,T;.....1,) geothermal gradient flow heat International Standard SI Wm!°c"! m” °C Wm”
function of thermal conductivity; the geothermal gradient Borehole Earth's Surface z yields the for the region, the
Flow (k) (0T/0z)
Heat flow (q) as a Measurement of heat flow. plotted against thermal conductivity (k) Conversion from
heat function Conductivity Gradient
10 in (q)
Chapter a) Change heat flow as a 10.13 in a borehole. b) T measured 10.2 TABLE literature. Thermal Geothermal Flow
320 10.12 in a FIGURE (z) the Heat
FIGURE Change b) ‘
‘ |
| |
28