ITRI.-85191
PRKPRINT
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TMRMAL PROPERTIES OF ROCk SALT AND
QUARTZ KONZONITE TO 573 I AND 50-MPa
CONFINING PRESSURE
W. B. Durhan
A. [. Abey
T t m paper was prepared r'cr p v . i ' n '
at thr <?('th ASML-AlCliE National M M : '<
ConfpreriLP, Milwaukee, Wl, Auijii--.: .'-'•.
March
This is a prrarint of i aaa«
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chantcs may bt madt M a n aaMicaiiM. rhb anailM is tutt
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RSTRIBuDI OF THIS OOMEM IS U H E D
Thermal Properties ef Rock Salt and Buartt Monwwlte
to 573 t and 5 0 - « a confining Pressure
»• B. Duthit
Senior S c i e n t i s t
Lawrence Uvermore National laboratory
Mvermore, California
A. G. «b«y
Senior Scientist
Lawrence Livetinore national laboratory
UVCEMCTO. California
Miltract
Measurements ot thetmal conductivity, thetnal dlffuslvity, and thermal linear e«panat«n have been Md*
on two rock types, a rook s a l t and a q e a r u awuonUe,
at temperatures front JflO tu 573 K and confMnq \>tt*sures from 10 to 50 HW. The aaeiplea « r e taken fro*
Seep rock formations under conaideration aa poaaible
s i t e s for a nuclear paste repository—the rock s a l t
from a domal salt formation at hvery Island, UiuUiana,
and the quartz aanionlte from the Climax Stock, Nevada
T<>st S i t e , Nevada. The testlncj temperature and pres­
sures are f&eanr *o bracket conditions eirpeoted in the
repository.
tn both rock types, the thetstai properties ahox a
strong dependence upon temperature and a veak or n o n dependence upon conflnlna pressure. Tbermal n w t a l v Ity and rUffusivity both dtcrtaae »lth increasing tenpe-atore In appraklnataly linear fashion for samples
nhieh have not been previously heated, at 50 MP» in
both rocks this decrease closely aatehes the nessured
ot «irpeet«« intrinaic lerack-ftee) behavior of the
M t t ' i a l . Jrallininary indications fros the quart! iwnlonite suggest that conductivity and diffuslvlty at It*
pressure and temperature »ay decrease as a result of
heat treat»»nt above «0<1 ».
IWeMlftlSWMMIlHMlia
A,
INTRODUCTION
The thermal properties of geological Materials at
e l e c t e d temperatures and pressures have attracted in­
creased attention because of recent interest in dis­
posing of nuclear waste in mined cock repositories.
Accurate prediction of the long term response (over
10* - 10 years] of a waste repository to the
thermal load of the waste requires the best possible
determination of the physical properties of the re­
pository rock at In sit physical and chemical condi­
tions, in particular, knowledge of the thormal conduc­
tivity and difi'isivity is required in order to model
temperature distribution in time and space around the
repository. The model in turn will help to predict ex­
pansions, stresses, microfracturing, and permeability
chanqes in the repository.
Thermal properties data on rocks at room pressure
abound, but because of experimental complexity and a
lack of need, such data at pressures appropriate to the
earth's upper crust are rather sparse. Hydrostatic
pressure can be expected to have both an intrinsic and
an extrinsic effect upon thermal conductivity and diffusivity in rocks: the intrinsic effect, because in­
teratomic distances are changed, and the extrinsic ef­
fect, because of the presence of pores and microfrac­
tures. Some data have been taken in the intrinsic
range, either at very high pressure where porosity has
been squeezed out of existence or on single crystals
where porosity doesn't e x i s t . Bridgman (1) has shown
that the intrinsic effect of pressure upon thermal con­
ductivity i s positive but quite small. In measurements
to 1.2-CPa confining pressure he found the conductivity
of Naci increased linearly at a rate of 3,6% per 100
MPa, and that of basalt increased at a rate of 0.47%
s
1
per 100 MPa. The intrinsic effect of pressure on
thermal diffuslvlty has also been measured on certain
minerals by Kleff&r et al. 12): for NaCl diffusivlty
increases i t a rate of 3.11 per 100 HPa per P s l fl
GPaj for quart: ± c diffusivity Increases at a rate
of 1,71 per 100 HPa for P < 3,0 GPa,
The effect of porosity on thermal conductivity haa
been modeled and confirmed by measurement to be sub­
stantial, with the magnitude of the effect dependent on
the arrangement of the pore space (aee Sweet O] for a
review), Walsh and Decker (4) related thermal conduc­
tivity to crack porosity theoretically and then uned
existing crack porosity vs. pressure relationships in
order to construct a model of thermal conductivity vs.
pressure. Experimentation (4} using uniaxial stress to
approximate hydrostatic pressures supported tho model
well: intrinsic and bulk thermal conductivity d i f f e r ^
by as much as )5t in dry rock at zero pressure. Th'>
effect of pressure parallels the pressure dependence of
crack porosity. That dependence is qualitatively simi­
lar for moat dense, crystallite rncks: strongest at
zero pressure, decreasing steadily with increasing
pressure to the intrinsic dependence where, presumably,
a l l cracks have closed. The extrinsic effect becomes
insignificant, depending on rock tvpe, at pressures of
50 to 300 MPa (see, for instance, Brace (51). The lo­
cation of a waste repository, somewhere between the
surface (lithostatic P * 0] and 1 to 2 km deep (p « 25
to 50 MPa), puts the repository rock where the ex­
trinsic pressure effect is expected to be very strong.
Therefore, t-he application of room pressure thermal
properties measurements to the repository situation
must be considered suspect.
If such measurements are made at elevated temp­
erature, the application to a repository becomes SUBpect for yet another reason. It U well known that
heating a rock, unifornly or otherwise, can lead to
raicrofracturing (Rienter and Simmons (6)j Cooper and
Simmons (?li Johnson et al. ( | ) : Johnson and'Gangi
{9)1. The cause is thermal expansion mismatches in a
polymineralic matrix, whose mineral components themselvei are {in most cases) anisotropic in their expan­
s i v i t y . The application of pressure would close some
1
of these cracks or, if the heating vere done under
pressure, might even suppress s o n of the mlcrofracturlng altogether.
The present work reports the f i r s t results from s
nevly built apparatus designed bo measure thermal con­
ductivity, diffusivlty, and linear expansion under s i ­
multaneous elevated temperature and hydrostatic (gas)
confining pressure. Results are reported for two
rocks, a rook salt and a quartz monionite,
SAMPLE MATERIAL
flow is established. For the diffueivity measurement a
transient heat flow condition, usually a (0* to 90-s
puis* of the central heater, Is imposed. Sample length
it monitored continuously,
iKiume of the likelihood that thermal expansion,
change! In permeability, and changes in thermal prop­
erties share i t leair one common mechanism tmlctofracturing), there i t a distinct need to understand as
much ss possible about how reversible changes (such as
opining and closing of existing microfractures) and i r ­
reversible changes (much as creation of new microfrac­
tures) effect the thermal properties. For this reason,
metiutlments are made at pressures IP) and temperatures
IT) bracketing those expected In s repository. The
path in (P,T| space that the experiment follows Is cho­
sen mo that mlcrofracturlng is postponed aa much as is
reasonable. Thus, (low P, low T) and (high P, low T)
are explored before (high p, high T) and all are ex­
plored before (low P, high T).
The rocks studied here are s i t e specific. The
rock salt samples were taken from a mine at Avery
Island, Louisiana in one of several rock salt forma­
tions under consideration for a waste repository. The
quartz raonzonite vas cored at « location adjacent to
the Bite of a test spent fuel repository in the Climax
Stock at the Nevada Test s i t e , Nevada.
The took salt samples were cut from a 400-mm diam­
eter core (C-lll, supplied by M/SPBC t n c , Rapid City, RESULTS
South Dakota. The core was taken from the floor of
workings at the 163-m level at the s i t e of an In situ
Rock Salt
heater test in the Avery Island domal salt formation.
Two samples of Avery laland rock salt were
Chemical analysed of samples from the Avery Island Mine teated. The results for thermal conductivity, dtfshow roughly 99.11 NaCl (by weight), 0.7% water lnsolfuslvtty, and linear expansion are shown in Figs. 1-3,
ubles, 0.21 Casoj (anhydrite), and 0.2t vater
respectively. The first sample burst i t s jacket naar
[Kaufmann 1^0)). The rock salt has a porosity of ap­
473 x and SO HP*, so the only data at known effective
proximately II and the grain size of the halite ranges
pressure (defined as.conflning pressure minuB pore
from 2.5 to 15 inn with an average of 7,5 mm (Carter and pressure) are at room temperature (10 to 50 MPa) and
Hansen | U ) | . The density of the rock salt his not
373 K (SO HPa only). The jacknt burst occurred because
been measured. The density of pure NaCl at room temp­
of the high thermal expansivity of the rock salt rela­
erature is 2,16 ngA» .
tive to the copper (4.5 « l O " ! vs. 1.0 * 10"
The Climax Stock quartz monzonlte has been charac­ IT ). Presumably, once the jacket integrity va.>,
l o s t , the pressure medium was free to enter the pores
terized In detail by Izett (12) and Maldonado (13).
and cracks of the sample and the effective pressure
Average composition of several samples taken from the
dropped well below the confining pressure, The jacket
U-15-A drill hole roughly 300 m horizontally distant
from the spent fuel repository vas determined ai 38% by leak vas rather large, so it in assumed that the ef­
weight quartz, 251 alkali feldspar, 401 pla^ioclase, (1 fective pressure f e l l to near »ero. No change in the
biotlte, and II accessory minerals (131. Grain size in jacket deaign was mado for the second rock salt Banple:
the matrix is 1-1 1/2 mm but is marker! by quarts pheno- thus, in anticipation of another jacket failure between
cryetr 15-101 by volume) averaging 4 no in diameter and 373 and 473 K, temperature increments were made smaller
and all pressures were explored (in HK order SO, 10,
by large orrroclase phenocrysts (5t by volume) averag­
10 HPa) at each new temperature. The second sample
ing 50 inn in ength with some as long aa 150 mm. The
orthnclase phenocrysts are uniformly distributed in the jacket failed at 438 T and 10 HPa, Trie first run was
rock, A Laboratory-sized sample measuring SO cm or
mor* in volume which does not encounter an orthoclaae
phenocryst is unusual. The rock hau a porosity of ap­
1
'
proximately It and has a density of approximately 2.64
Avery Island Salt
Ng/m .
4
Run 1 Hun 2
3
5
- 1
5
1
3
1
1
1
EXPERIMENTAL TCCUHQOE
*
10 MPa _
a
.10 MPa
50 MPa
The measurement apparatus Is described by Abey at
O P « P a l . 114). The samples to be measured are thick-mailed
cylinders 203 aa in length with inner and outer diam­
eters of 19 mm and 327 I B , respectively, For eaue of
machining, each sample is male up of three equally
sized cylinders of rock. The samples are clad in a
leak-tight, thln-valled copper jackut to exclude the
pressure medium (argon) fro* the rock. Temperature la
iI
measured by eight thermocouples positioned at eight
31
i
i
I
i
I
300
400
500
6O0
different radii in the sample. The large sample s l i e
and thermocouple redundancy (only two are necessary for
Temperature IK)
a measurement! were chosen in order to increase the
validity of the measurement of large-grained <>5mm)
Fig. 1. Thermal conductivity vs. temperature and pres­
samples and bo minimize the effects of local variation sure ta measured on two samples of Avery island rock
in a lampl . The measurement is conducted Inside an
salt. The large squares around the higher temperature
externally heated pressure vessel.
p i n t s of Run 1 indicate the measurements vere made
Beat flow i s established in the sample in an ap­
following jacket failure (see t e x t ) . The error bar
proximately axisymmetrlc radial pattern by a small
indicates the typical rriae of random error (one stan­
heater located along the axis of the temple, for the
dard deviation), The I
-d curve is dram free-hand
thermal conductivity measurement a steady-stats heat
through the data.
KB
^i
~r—i—i
r
Avery Island Salt
•
f\l
i
i
Run 1 Hun 2
0
•
10 MPs _
•
30 MP:
i
50 MPs
1
i"
"K.
^-frS 1
i
i
300
i
350
400
i
1
1
450
500
550
609
Temperature (K)
Fig. 2. Thermal diffusivity vs. temperature and pres­
sure as measured en two samples of Avery Island rock
s a l t . The same conventions .ipply as in Fi$. 1.
continued to its intended limit of 573 K following the
jacket failure. The second run was terminated
immediately fallowing the jacket failure.
The the--*l conductivity [Fig. 1) and thermal dtfEuaivity IFiy. 2) show good jgreement between runs,
Bath decrease strongly with increasing temperature*
Thermal conductivity shows no discernible presmre de­
pendence where the jacket is intact, and shows no ob­
vious discontinuity when the jacket loses i t s integ­
rity. Thermal diffusivity shows no dependence en pres­
sure from 3D co 50 MPa, but apparently increases by ap­
proximately 201 when pressure drops to 10 KPa. The ef­
fect is seen in both runs and at all temperatures
tested. Based nn the direct relationship between con­
ductivity and diffusivity, the same pressure effect
( i . e . , none) would be expected for each. Based on the
microcradk model either no ore .Mure dependence (rock
has no microcracks) nr a decrease of dLffusivity with
pressure (rock has microcracks) would be anticipated.
The rise of dir'fusivity with decreasing pressure is
therefore considered anomalous and is tentatively ex­
plained away as a systematic error. The veracity of
this explanation will be tested when a careful calibra­
tion of the apparatus is made.
The most extensive thermal expansion data
(Pig. 3} came from the first run, where the temperature
•'\
N,IM0
change vat twice that of the second* The expansivity
rises a lightly with increasing temperature. The con*
fining pressure for the first run wis SO KPa for a l l
pointb, but above 473 R the pore pressure was also
close to 50 MPa, so the data indicate no dependence of
expansivity upon effective pressure between 300 and
573 R. The band of data in Fig. 3 from the second run
represents repeated short (AT • 40 to 80 R) excursions
upward and downward in temperature at several confining
pressures. Ho dependence upon confining pressure was
seen, nor was any temperature dependence seen, not sur­
prising in light of the snail temperature steps taken
and the moderate temperature dependence detected in
run 1. The width of the band conpared to the height of
the error bar for run 1 is an indication of the repro­
ducibility of the thermal expansion data.
Quartz Rontonite
One sample of Climax Stock quart2 monionite has
been teBted to date, and a jacket failure (cajsed this
time by a reaction between the copper jacket and pyr i t e , r>s i inclusions in the rock) terminated that
run at the same point, and after the same traverse in
(P,T) space as the first rock salt run. The run was
terminated Immediately following the jacket failure.
The results for thermal conductivity, diffusivity, and
linear expansion are given in Figs. 4-6, respectively.
The thermal conductivity of the quartz monwmite
(Fig. 4) at 50 MPa shows a distinct decrease with in­
creasing temperature* Values at any given temperature
are approximately half those for rock s a l t . At room
temperature there is no discernible dependence -of ther­
mal conductivity upon pressure for 10 MPa < P < 50
MPa. The room temperature pressure independence iemalned even following the excursion to 423 K at 50
MPa. Thermal diffusivity (Fig, 1) also decreases with
increasing temperature at 50 MPa, shows no p.-essure de­
pendence at room temperature for 10 MPa < P s 50 Mpo,
and shows the same anomalous rise at 10 MPa as rock
salt, reinforcing the notion that the rifle represents
system problems.
The coefficient of thermal linear expansion rturinq
a single heating episode from room temperature to 460 K
is shown in Fig. 6. The rate of expansion i& indepen­
dent of temperature from 320 K to approximately W> K
and increases steadily vith temperaturp from 37S m
468 K.
2
St).I
C'.mdj; Slock Ut..in,' M nvt>"ili'
t
| » 10MP.1
Yanq
30
•l
•
Ti <-i.i.iv ,• aovifti
I . so«r
u
>
1°
°
:
P'JII i-T.i
OMPj
25
4
E 2.0
400
600
Temperature |K)
301)
Fig. 3. Thermal linear expansivity of two aamplcB of
Avery Island s a l t . Yang's |22| curve 1B the expansiv­
ity of single crystal halite. The ahoi,: dashed curve
represents our data if a system calibration Is applied,
that calibration being our measurement? on quartz nonzonlte against Heard's iW measurements on the sane
rock (Pig. 6),
100
5
Temperalure |KI
Pig. 4. Thermal conductivity of Climax Stock quartz
monzenite vs. temperature and pressure.
1
—1
1
-
Climax Slock Quart! Monjoniie
f
1
• 10 MPa
• 30 MPa
A 50 MPa
1.0
£ D.5
300
3H>
.100
450
Ti'miicraturr- !K)
"'!!. 5. Thermal dlffusivlty of climax Stock qqartt
monzonlte as a function nf temperature and pressure.
DISCUSSION
expansivity [ftichter and Simons |6); Cooper and
Simons (15) j Bruner (16) j Wong and Brace (17); Heard
(IB))* The sioothly Increasing coefficient of thermal
linear expansion/ uninterrupted by the Jacket rupture
and drop In effective pressure, indicates that uniform
heating of rock s a l t generates very l i t t l e motivating
force for mtcrofracturing. The thermal conductivity in
such A material could only be expected to show no ex­
trinsic pressure dependence.
It should be pointed out that extensive testing of
a similar rock salt, Southeastern New Mexico bedded
s a l t , has demonstrated through mechanical testing
(Wawers<k and Harmun (19)) and gas pecmwbilUv mea­
surements (Sutherland and Cove (20)) that crack poros­
ity in the starting material In the laboratory (as op­
posed to in situ) is non-3cro. In both sets of experi­
ments, those authors conclude that the source of crock
porosity is sample handling (coring, transport, experi­
mental preparation) because the manifestations of crark
porosity (nonlinear pressure-volume relationship at
lowest pressures, i n i t i a l high permeability at low
pressure; can be made to disappear permanently with the
application of pressures in the 10-10 MPa range. Salt
Is known to deform plastically with relative pose at
differential stresses of the sane order (see, for exam­
ple, Carter and Heard (21^)), GO permanent crack closure
under low pressures Is plausible. In the present wnrt,
no measurements were made at zero effective pressure
without the sample first being subjected to effective
pressures of 10 MPa or more. Therefore, it is posalblo
that any i n i t i a l cracks which might have impeded heat
transport in our samples were squeezed out of existence
by the tine the first measurements were made. The bnhavlor of the southeastern New Mexico rock salt and of
the Avery Island rock gait appear to he consistent.
The thermal properties of rock salt as measured
here fignnrinq the anomaloi^ behavior of diffusivlty at
ID MPa! am not dependent upon confining pressure, tn
light of the suggested role of microcracks In rocks,
such behavior might be expected only in a mononlneralic
The salt data are compared in Fig. 1 and Fig. i tn
rock (such as rock salt! whose single phase 1B Iso­
an extensive compilation by Yang 2^> of single crystal
tropic. H--1 ite has cubic symmetry and may be clo9e
enough to isotropic that significant (from the point of HaCl data. The moat serious disagreement is the diffusivlty which falls about 201 below Yang's valuer, at
view of heat storage and transport) thermal cracking
any given temperature. The apparent disagreement in
rices not occur. The data gathered here are strongly
thermal expansivity fFig. 3) may vanish once system
self-cons is tent lagain excepting diffusivity at 10
calibration is complete. If the correction required t->
MPa), given the well-understood and demonstrated rela­
bring the expansion data for the quartz monzonite inro
tionship between microfracturing and enhanced thermal
agreement with Heard's (W data (see Fig. 6', is ap­
plied to our rock salt data, the short dashed curve ,'
Fig. 3 resultB, That curve is very close to Yanq's.
Cl.n.ax!; ock li..i'l.' Miirizomlf
Additional thermal conductivity mejfsurements on
rock flalt for waste repository site-specific studies
are reported by Morgan (2^1 for two salts including
Avery Island, and by Acton \\k\ and Sweet and McCreiqht
14
(25) for the Southeastern New Mexico rock s a l t . These
y ^
^Trmstudv
data are compared in Table 1. Only in the present
study wan true hydrostatic pressure applied to the tr >*
^ S
150 MPal
specimens. The data of Sweet and MeCreight (25) agree
well
with our data, Acton's data J24) are scattered,
'
10
^Hfttt(JI3?6MPal"
and Morgan's Avery Island data are scattered hut con­
sistently much lower than our own. Although Morgan's
samples were taken from a point in the mine hori­
zontally separated from the source of our own by less
than 50 m, he reports that tr* samples are weak anr]
~~- Calculated
friable, rather in contrast to our own. A possible ex­
planation is that his samples cj*e from 50-nn-diameter
!
1
L.
core while ours came from 4DD-mm core. It is plausible
350
400
450
500
300
that the lower conductivities reported by Morgan are
the reBult of excessive fractures and microfractures
Temperature (K)
within his samples which were incurred during core
drilling.
Fig. 6. Thermal linear expansivity of Climax Stock
The thermal properties data on quartz monzonite
quartz monzonite at 50 MPa. Data ace compared to
ace too incomplete for detailed analysis at this
Heard's (18J measurements at 27.6 MPa on the same rock
point. Thermal conductivity shows no pressure depen­
type and to an "intrinsic' expansivity calculated by
dence at roojn temperature, even following heating tn
averaging the expansivities of the individual Minerals
423 K at 50 HPa. This behavior would suggest that the
making up the rock, weighted according to their volume
percentage in the rock.
%
n
-^;;::r.'-
—-
TABLE 1.
Comparison of thermal conductivity
measurements.
Thermal conductivity IW/mK)
5 2
300 R
373 K
473 K 573 K
This study (AI)
6.3
5.3
4.0
3.3
Morgan (AI> 1,23)
4.0
3.2
2.6
2.2
Acton (SENM) 124)
8.5
6.3
Sweet t, McCreight
(SBNHI (25)
6.0
4.7
3.6
2.9
This sturiv
Tli 15 study
"For halite/anhydrite mixed-rock with >5n« halite
(conductivity increases with increasing purity of
rock s a l t ) .
One other set of thermal conductivity measurements
i s available for the quartz wnizonite 127) and these
are Bhown in Pig. 4. The Pratt et al. (27) data uore
taken at 0-HPa effective pressure, and where there is
overlap (room temperature and 173 K) the agreement with
our data la good. A higher temperature point at 473 hy
Pratt et a l . f a l l s distinctly below the trend pf the
lower temperature data and may reflect fflicrofrarturing.
Microfracturing is anticipated in the quartz monzonite at higher Mperatures and lower pressures on
the basis of theoretical considerations mentioned abovp
and on the basis of the thermal expans'.m results of
'•no
?on
100
Beard (19). Heard's curve for 27.6-MPs pressure is
shown in Pig, 6 for comparison with our own data at 50
MPa. At lower pressures, Heard finds systematically
higher expansivities and suggests that these are caused
Pig. 7. Thermal conductivity and diffusivity of Avery
Island rock salt measured here compared to single crys­ by m i c r o f r a c t u r e .
The difference in thermal linear expansion
tal data compiled by Yang (22).
(Pig. b, between our data at SO MPa and th.-it of Heard
(181 at 27.6 MPa is probably more closely related to j
II porosity reported tor the Climax Stock quartz monzo- lack of calibration of our system rather than to the
difference in pressure- First, our 50-MPa curve indi­
nite (13) does not apply to our sample, or that the
cates a higher expansivity than the 27.6-MPa, which is
porosity is tied up in round pores which are not
not reasonable. Second, the expected inttir.sw- expan­
strongly influenced hy pressures below SO MPa, or that
sivity
of the rock, calculated by weinhinq the rxpanthe porosity is tied up in very flat cracks which close
s i v i t y of each phase by its volume concentration in the
completely at pressures below 10 MPa. Pressure-volume
relationships measured for the granodiarite in the Cli­ rock, falls close to Heard's curve at 27.6 MPa suggest­
max stock, a close sister to the quartz monzonite, show ing that Heard's data are closer to the truth than our
own. As mentioned ahsve, if Heard's data are used 'o
no evidence of such a high ( i . e . , II) crack porosity
influenced by pressure below 10 MPa 1261. In tact, the calibrate our thermal expansion measurement, our data
on the thermal expansivity of salt also fall nicely
hydrostat shown by Schock et al. |26| contrasted with
into place with the intrinsic exparsivity iFig. 31.
that of the Casco qranite used by Walsh and Decker (4)
SWtHRY AND CONCLUSIONS
in an application of t'^ir model is revealing; the
Casco granite shows a crack porosity of 0.41 by the
Walsh and Decker definition ( i . e . , where a straight
Prom thermal properties measurements carried out
line extension of the Intrinsic portion of the P-V
at elevated effective confining pressure and elevated
curve Intersects the volume strain axis)! the P-V curve temperature on Avery Island rock gait and climax Stock
for the climax Stock granodiorite, using the sane defi­ quartz monzonite, both of interest for the country's
nition, shows a crack porosity of well under 0.051.
nuclear w*jste Isolation effort, we conclude:
The 0.41 crack porosity in the Walsh and Decker model
1) ?or 0 < P < 50 MPa and 300 ; T * 573 S, the
leads, to a predicted 151 change in thermal conductivity thermal conductivity, diffuaivity, and linear expansion
tor dry rock between 0 and 100 MPa. It all other fac­
of the rock salt are approximately the intrinsic values
tors in the Walsh and Decker equation 17) ore un­
for single crystal h a l i t e .
changed, a 0,05< crack porosity would » a n only a 21
2) Handling of salt samples between the field and
change in conductivity for the quartz monzonite.
laboratory may damage the material sufficiently that
,L_
zero pressure thermal conductivity of the bulk may be
lowered by as much as 50». The effect on corductivity
can be permanently reversed by subjecting the rock to
pressures of 10 MPa or more.
3) At room temperature, neither unhealed quartz
monzonite nor quartz iflonzonite heated as high as 423 K
at 50 MPa shows any effect of confining pressure upon
themal transport behavior. The thermal expansivity of
the rock at 50 MPa for 300 < T < 437 is is approximately
i t s intrinsic expansivity.
ACKNOWLEDGMENT
This work was performed foe the N a t i o n a l Waste Terminal
S t o r a g e Program INHTS) of ' h e U . S . Department of Energy
by the Laurence Livermore National Laboratory under
c o n t r a c t numh«
r
W-7405-ENC-48.
REFERENCES
1
;;. B i l l
nridgman, P. w., The P h y s i c s nf High P r e s s u r e ,
and S o n s , Londoi , 1952, pp. 1 2 0 - 1 2 9 .
2 Sipffer, S. w., Cctting, .1. C , and Kennedy, G.
C , "Kxper Imi'ntal Determination of the Pressure Depen­
dence of the Therma DiffusrJity of Teflon, Sodium
Chloride, Quartz, and S-'lica," Journal of Geophysical
Research, Vr.l. 91, No. 17, June 1976, pp. 101B-3024.
1
1 Sweet, .1. N. "Pressure Effects on Thermal Coniuetivitv and Expansion of Geologic Materials," Sandia
laboratories Report SANDT<-1991, Sandia Laboratories,
Mbuquprqiie, MM. 1979, 46 pp.
r
4 walsi', J. a. and Docker, K. R., "Effect of
Pressure and Situratinq Fluid on the Thermal Conduc­
tivity of Compact Rock," Journal of Geophysical
Research, Vol, 7',, No. 12, Jjne 1986, pp. 1051-3061.
5 P r a m , w. P . , "Some New Measurements of Linear
C o m p r e s s i b i l i t y of Rocks," .Journal of Geophysical
R e s e a r c h , Vol. 70, Nn. 2, j , n . 1965, pp. 391-39B.
6 R i c h r e r , D. and Sirrjrons, G., "Thermal Expansion
o f I g n e o u s Rocks," I n t e r n a t i o n a l Journal of Rock Her'nr, i c s and Mining S c i e n c e s , v o l , 11, 1974, pp, 4 0 3 - 4 1 1 .
7 c o o p e r , H. W. and Simmons, G., "Thermal C y c l i n g
Cracks in Three Igneous Rock?," i n t e r n a t i o n a l Journal
nf Reck Mechanic? and Mining S c i e n c e s , v o l . 15, 197B,
pp.
(45-14s7
3 Jonr.sor, 3 , Gangi, A. P . , and Handin, J . ,
"Cherrnl Cracking of Rock S u b j e c t e d t o slow, Uniform
>nperatur<> Changes," P r o c e e d i n g s of the 19th U . S . Sym­
posium on Rock Mechanics, U n i v e r s i t y o f Nevada-Reno,
1978, pp. 2 5 9 - 2 6 7 .
9 .'ohr.son, D. and Gangi, A. F., "Thermal Cracking
of Km—urifore.ly Heated, Thick-Hailed Hollow Cylinders
nf westerly Granite," Proceedings of the 21st U.S. Sym­
posium on Rock Mechanics, Rolla, MO, in press.
10 Kaufmann, D. « - , Sodium c h l o r i d e ,
New yark, 19«fl, p , 1*7.
Reinhold,
13 Maldonado, P., "Sumiary of the Geology and
Physical Properties of the Cllnax Stock Nevada Test
Site," Open Pile Report 77-356, United States
Geological Survey, 1977, 26 pp.
14 Abey, A. E. and Durham, H. B., Trimmer, D. A.,
and Dihley, L, 1 . , "An Apparatus for Determining the
Thermal Properties of Large Geological Samples at
Pressures to 0.2 GPa and at Temperatures to 750 K,"
preprint, to be submitted to Review of Scientific
Instruments.
15 Cooper, H. w. and Simmons, G., "The Effect of
Cracks on the Thermal Expansion of Rocks," Earth and
Planetary Science Letters, Vol. 36, 1977, pp. 404-412.
IS Bruner, w. M,, "Crack Growth and the
Thetffloelastic Behavior of Rocks," Journal of
Geophysical Research, Vol. 84, No. B10, Sept. 1979,
pp. 5578-5590.
17 Hong, T . - F . and B r a c e , W. P . , "Thermal
Expansion of P o c k s : Some Measurements a t High
P r e s s u r e , " TectonophVBJcB, V o l . 5 7 , 1 9 7 9 , p p . 9 5 - 1 1 7 .
18 Heard, H. C , "Thermal Expansion and I n f e r r e d
P e r m e a b i l i t y of Climax Quartz Monzonite to 300°C and
27.fi MPa," I n t e r n a t i o n a l Journal of Rock Mechanics and
Mining S c i e n c e s , v o l . 1 7 , 1 9 8 0 , p p . 2 8 9 - 2 9 6 .
19 wawersik, K. and Hannum, D.
B e h a v l r of New Mexico Rock S a l t In
Compression Up t o 2 0 0 ° c , " Journal of
R e s e a r c h , V o l . 8 5 , No, B2, 1 9 8 9 , pp.
W., "Mechanical
TiUxlal
Geophysical
891-900.
20 Sutherland, H. J, and cave, s. P., "Argon nip
permeability of new Hexico Rock Salt under Hydrostilic
Compression," International Journal of Rock Mechanics
and Mining Sciences, Vol. 17, 1980, pp. 281-188."
21 c a r t e r , N. L. and Heard, H. c . "Temperatuif
and Rate Dependent Deformation of H a l i t e , " American
Journal of S c i e n c e , V o l . 569, Oct. 1970. pp. 19]-24"9.
22 ifang, J . M., " T h e m o p h y e i c a l P r o p e r t i e s , " on
Handbook of Rock S a l t P r o p e r t i e s Data, L. H. Gevantman,
e d . , N a t i o n a l Bureau of S t a n d a r d s , 1 9 8 1 , c h p t . 4.
23 Morgan, M.
S a l t from Louisiana
Laboratory T e c h n i c a l
National l a b o r a t o r y ,
T . , "Thermal C o n d u c t i v i t y of Bock
S a l t Domes." Oak nidgp National
Memorandum ORNL/TM-6B 9, Oak Ring*
Oak Ridge, TN, 1975, IS pp.
n
24 Acton, R, r j . , "Thermal C o n d u c t i v i t y of S.K.
New Hexico Rock S a l t and A n h y d r i t e , " in P r o c e e d i n g s of
the 15th I n t e r n a t i o n a l Conference on Thermal
C o n d u c t i v i t y , V. V. M i r k o v l c h , e d . , Plenum P r e s s , New
York, 1 9 7 8 , p p . 2 6 1 - 2 7 6 .
25 Sweet, J. N. and McCreight, J. E., "Thermal
Conductivity of Rocksalt and other Geolo/ic Materials
from the Site of the Proposed waBte Isolation Pilot
Plant {abstract)," in Abstracts, 16th International
Thermal Conductivity Conference, IIT <esearch
Institute, Chicago, 1979, pp. 31-32.
11 Carter, N. L. and Hansen, r. D., "Mechanical
Behavior of Avery Island Halite: A Preliminary
Analysis," Technical Report QNMl-100, Office of Nuclear
Haste Isolation, Battelle Industries, Columbus, OR,
19B0, 32 pp.
26 Schock, R. N,, Heard, H. C , and Stephens, D,
R,, "Stress-Strain Behavior of a Granodiortte and Two
Graywackes on Compression to 20 Rllobars," journal of
Geophysical Hesearch, Vol. 78, No. 26, 1973, pp.
5922-5941,
12 Izett, G. A., "Granite Exploration Hole, Area
15, Nevada Test Site, Nye county, Nevada—Intel im
Peport, Part C, Physical Properties," Trace Element
Memorandum Report 836-c, United States Geological
Survey, 1960, 36 pp.
27 Pra.:t, H. R., L i n g l e , R., and Schrauf, T . ,
"Laboratory Measured M a t e r i a l P r o p e r t i e s of Quartz
Monzonite, Climax S t o c k , Nevada Test S i t e , " Lawrence
Llvermore N a t i o n a l Laboratory Report UCRL-15073, Law­
rence Livermare N a t i o n a l Laboratory, Livermore, CA, 1979.