SESSION 6
MAGMA ENERGY: ENGINEERING FEASIBILITY OF
ENERGY EXTRACTION FROM MAGMA BODIES
R . K. Traeger
Geo Energy Technology Department I1
Sandia National Laboratories
Albuquerque, New Mexico 87185
ABSTRACT
Extensive quantities of high-quality energy are estimated
to be available from molten magma bodies existing within
10 Km of the U. S . continent's surface. A five-year study
sponsored by DOE/BES demonstrated that extraction of
energy from these melts was scientifically feasible. The
next stage of assessment is to evaluate the engineering
feasibility of energy extraction and provi\de a preliminary
economic evaluation. Should the second step demonstrate
engineering feasbibility, the third step would include
detailed economic, market and commercialization endeavors.
Evaluation of the engineering feasibility will be initiated in FY 8 4 in a program supported by DOE/GHTD and
managed by Dave Allen. The project will be managed by
Sandia Labs in James Kelsey's Geothermal Technology
Development Division. The project will continue to draw
on expertise throughout the country, ;especially the
scientific base established in the previous BES Magma
Energy Program.
Current plans, which will undoubtedly be modified as
research proceeds, are as follows:
FY 8 4 - 8 5
- System Integration -- overall system analysis
including preliminary market-.'studies,economic estimates
and overall hardware requirements to allow sensitivity
analyses for identification of major technological problem
areas
.
- Geophysics, Chemistry and Geological Surveys -review existing data, conduct relevant field experiments
and select three potential shallow sources.
- Geochemistry and Materials -- extend previous
research to the geology of specific sites, and initiate
experiments to identify field test hazards.
160
- Energy Extraction -- review extraction concepts
in terms of the specific sites under consideration and
initiate needed laboratory studies.
- Drilling Technology -- define systems required to
provide a 3 Km deep well to temperatures of 1000 C and
initiate prototype developments.
FY 87-88
- Site Characterization - - select an area for
shallow drilling and identify a specific site for a deep
clr i 11 hole.
- Logistics
for deep drilling.
--
obtain permits, access, etc. needed
- Hardware -- initiate fabrication of special
drilling, completion and logging tools.
- Systems -- continually update the systems
analyses and reevaluate the commercial viability of magma
energy.
FY 89-91
- Drill -- drill into magma body and complete the
well for energy extraction studies.
- Research -- provide diagnostics and experiments
for research needed in geothermal-magma systems to provide
a fundamental base for exploitation of other areas.
-
Reservoir Dynamics
--
initiate long-term studies
t o u n d e r s t a n d reservoir behavior.
This Magma Energy Project is closely related to other
as Drilling and Completions, Hot Dry
Rock and the Salton Sea, as well as the DOE/BES
Continental Scientific Drilling Program. All activities
will be closely coordinated with periodic reviews open to
all interested parties, through the National Research
Council's Continental Scientific Drilling Committee, and
through the normal publication and presentation channels.
DOE/GHTD programs
161
Engineering Feasibility of Extracting
Energy from Magma Bodies
R. K. Traeger
Sandia National Laboratories
earth's s u r f a c e .
program was carried out from 1975-1982 t o e v a l -
-research
uate
the
scientific
magma, i.e.,
of
feasibility
extracting
energy
from
to determine if there were any fundamental scien-
tific roadblocks to tapping molten magma bodies a t depth.
-- a g - E ? t by-Dr.
SaM&-Nationai
G. A
.
Kolstad.
tjUbGL
es w
gram man-
Research activities, managed by
Laboratories,
1
2
*-
1
162
the
Tentative tasks and schedules are presented for discussion and
critique.
A bibliography of past publications on magma energy
1
(1) obtain engineering design data needed for t.echnica1 and
economic evaluations;
i
(2) verify feasibility in a field test involving a shallow
( 3 km) magma system: and
( 3 ) coordinate the magma project with other GHTD programs
and BES research
in the geosciences to provide
technological and scientific spinoff.
163
the maximum
System Integration
Site Selection
Geochemistry and Materials
Drilling and Completion
Energy Extraction
The following discussion will briefly review plans for each of
these areas.
RESEARCH AND DEVELOPMENT ACTIVITIES
The
outlined
activities,
though currently
envisioned
to
meet the program needs, are likely to be revised a s the program
develops.
Detailed annual reviews with knowledgeable scien-
tists and engineers will provide a basis for program direction
and identification of specific R&D tasks.
SYSTEM INTEGRATION:
An overall model, including resource
location and size, land and drilling access, well drilling and
completion operations, required logging, energy extraction processes and hardware, bnd final energy distribution is needed to
identify the major
sources.
drilling
uncertainties in developing magma
Sensitivity
and
analyses made
completion
or
energy
needed to identify critical R&D areas.
on
energy
subsystems, such
extraction
as
systems, are
The analyses will then
provide the basis for economic evaluation and market considerat ions.
-
This activity will focus the R&D efforts toward developing
an engineering design and a realistic economic analysis.
ific activities proposed for FY'84 are:
164
Spec-
1.
Develop a n overall system concept
2.
Conduct a preliminary economic analysis
3.
Define a program plan f o r achieving the objectives
4.
Manage program integration, coordination and resources.
These activities are expected to continue through the program
l i f e with program plans and
ually updated.
economic estimates being
contin-
The tentative program plan is s h o w n i n T a b l e 1.
165
Table 1
System Integration
Phase I
Ia I b IC
FY F Y FY
Activity
Develop overall system concept and
conduct preliminary economic analysis
Develop detailed program plan for Phase Ib
through Phase IIIc
Coordinate tasks with USGS, CSDP, and other
geothermal programs: conduct annual interagency program reviews
Coordinate geochemistry activities with
materials needs of energy extraction and
drilling technology tasks
Manage program resources, integrate contractor efforts and prepare annual reports
as well as technology updates
Negotiate test site acquisition and coordinate
field activities
A
A
IL
Ir
I
87
86
85
84
2
1
Phase I 1
IIa I I b
FY
A -
L
1L
-
H-
I
Phase 1 1 1
IIIa IIIb IIIc
I
SITE SELECTION:
The existence and location of magma bodies
can be inferred from surface manifestations such as flows and
eruptions,
and
Yellowstone,
magma
Long
measurements.
has been
Valley
identified
and
others
areas
in
through
such
as
geophysical
Extensive work by the USGS and others a t Kilauea
Iki was performed
to evaluate geophysical exploration
niques appropriate for locating magma
(Colp, 1982).
A
techsurvey
of petroleum exploration geophysicists indicated general agreement that existing seismic techniques could identiEy magma body
structures (Hardee, 1982).
The emphasis of this program activity will be t o identify a
shallow (1-5 km) magma body for pilot studies on resource characterization, drilling, and energy extraction.
Although such a
shallow body may not be of commercial size, it will provide for
realistic extension of the past work in Kilauea Iki while min-
This site identification will
imizing cost and safety risks.
start with the preliminary survey of shallow magma systems that
was recently carried out by Hardee (1983).
In FYI84 this activity will review existing geological and
geophysical data to identify three shallow magma sites.
data will include such items as:
USGS
seismic
profiles
for
These
a review of the COCORP and
shallow
bodies
(they
have
historically been looking only at the very deep mantle):
analysis of
the current work proceeding
in
an
the Continental
Scientific Drilling Program at Long Valley, the Valles Caldera,
and
the Salton Sea; and an analysis of existing data from
167
Medicine Lake, Calif. and Newberry Caldera, Ore.
When
geophysics
three
sites
have
been
and
other
experiments
narrowed
will
be
to
one,
carried
detailed
out
to
characterize the magma body and site potentia’l drill location.
A
preliminary schedule is shown in Table 2.
168
Table 2
Magma Location
Activity
Locate 3 sources within 1-3 krn
Refine data on 3 sources, assess risk
for each, narrow to one site
Conduct extensive tests to define site
in detail
Design/fabricate downhole diagnostic
technology
Conduct downhole experiments to define
magma reservoir characteristics
Phase
l a Ib
FY FY
84 85
-
I
Phase I 1
I Ia
IC
FY FY
86 8 7
-
I
Phase I 1 1
IIIb
IIIC
FY
90
FY
91
Previous work has used anal-
GEOCHEMISTRY AND MATERIALS:
yses of erupted gas and solids to provide a physical, and chemical picture of true in-situ magma composition.
These anal-
yses, plus
preliminary
laboratory experiments, have provided
estimates of engineering properties (such as viscosities, heat
transfer
zoeff icients,
e tc.)
and
material
compatibilities.
Further needed characterization data will be identified in thP
system
Work
study
performed
in
the
system
integration
activity.
is needed on the long-term compatibility of engineering
materials in magmatic environments.
The initial endeavor in FY'84 will be to gather information
on age, volume, composition, and position of recently erupted
flows at potential drilling sites.
to
develop
a
geological
model
These analyses will be used
of
the
system,
to
support
interpretation of geophysics, and to provide a base for future
materials evaluation.
The analyses will also be used to esti-
mate the properties of the in-situ molten rock for energy extraction studies and drilling designs.
Future
chemical
work
during
analysis of
drilling
cuttings
will
to help direct
identify specific material needs, and
traction plan.
include
on-site
geo-
the drilling,
update the energy ex-
Creep and stress corrosion studies on materials
may also be initiated.
See Table 3 for a proposed schedule.
170
Table 3
Geochemistry
&
Materials
Activity.
Experiments to define effects of volatiles
on material compatibility and heat transfer properties
la
FY
84
-
Ib
-
FY
IC
FY
IIa
FY
IIb
FY
85
86
87
88
.__
-Ai
Geochemistry vesiculation experiments on
magmas (different silica contents)
expected at selected site
A
Design/fabricate downhole geochemistry
diagnostic tools
1L
Conduct downhole geochemistry experiments
Phase I11
I
IIIa IIIb IIIc
FY
FY
FY
90
91
89
i
DRILLING AND COMPLETIONS:
well now a t 11.7 km
wells
(e.g.,
Preliminary
(Oil
1000°C
in
studies
Deep, "cold" wells [e.g., the Kola
&
Gas J. 1983)] and very hot, shallow
Kilauea
(Traeger
et
Iki)
have
al.,
1981)
been
drilled.
suggest
that
extensive cooling could be used to drill into'700OC formations.
Other work
(e.g.,
Friedman et al.,
1980) has indicated that
igneous rocks would become easier to drill as they approach
their melting temperature and that boreholes should be stable
until
high
enough
temperatures
for
partial
melt
of
the
formation rock are encountered.
Effort in this activity will be to define drilling and completion 'hardware and support systems f o r penetrating into t h e
shallow magma body.
Consideration will be given to conven-
tional hardware with extensive cooling.
needs will be
during FY'84.
Special development
identified and development programs
initiated
Definition should proceed sufficiently to allow
specification of the drilling system in FY'86-87.
will commence in FY'89.
(See Table 4.)
172
Drilling
Table 4
Drilling and Completions
Phase I1
Ia I b IC IIa IIb
-FY
FY FY FY
FY
84 85 86 87
88
Phase I
Activity
_.
-
Define system required to drill to 3 km
at maximum temperatures o f 1 0 0 O ' C
Develop and test prototype drilling
hardware
Refine prototype hardware and fabricate
necessary hardware for drilling test
well
Drill well to intercept magma body
Evaluate long-range options
abandon well and reclaim site
or
begin joint DOE/Industry program
to commercialize
-
I
_
--
Phase I11
IIIa
FY
89
/
C u r r e n t concepts f o r energy e x t r a c t i o n
ENERGY EXTRACTION:
i n c l u d e i n - s i t u v a p o r i z a t i o n of a h e a t t r a n s f e r f l u i d , w i t h sur-
f a c e c o n v e r s i o n t o e l e c t r i c i t y and g e n e r a t i o n of
and
(CO
H2) f r o m
I n s u p p o r t of
the
organic
materials
f i r s t concept,
at
synthesis gas
in-situ
conditions.
l a b o r a t o r y and f i e l d e x p e r i -
m e n t s h a v e y i e l d e d d a t a on e n e r g y t r a n s f e r r a t e s b e t w e e n w a t e r
and m o l t e n magma and h a v e p r o v i d e d
insight
m e c h a n i c s b e t w e e n w a t e r and t h e m o l t e n r o c k s .
cept,
is
t h e p r o d u c t i o n of
are appropriate
The second con-
s y n t h e s i s g a s from o r g a n i c s and w a t e r ,
conditions i n t h e
w e l l u n d e r s t o o d and t h e e x p e c t e d i n - s i t u
magma
reaction
into the
for t h e n e c e s s a r y r e a c t i o n s .
In
addi-
t i o n , e n h a n c e m e n t o f h y d r o g e n p r o d u c t i o n v i a w a t e r r e d u c t i o n by
t h e magmatic f e r r o u s
i r o n h a s been d e m o n s t r a t e d
i n t h e labor-
atory.
The
engineering f e a s i b i l i t y
study w i l l
be
oriented
Current plans
o b t a i n i n g e n g i n e e r i n g d a t a from t h e f i e l d t e s t .
a r e t o use o p e n - h o l e
heat
exchangers
(in
toward
which
water
reacts
d i r e c t l y w i t h m o l t e n magma), t h o u g h c l o s e d h e a t e x c h a n g e r s a r e
a l s o b e i n g d e s i g n e d , and t o e v a l u a t e some a s p e c t s of s y n t h e s i s
g a s p r o d u c t i o n ( l i m i t e d d e p t h w i l l require lower pressures t h a n
desired f o r chemical e q u i l i b r i a ) .
involve preliminary
magma
ciency,
and
design
consideration
of
of
I n FYI84 t h i s a c t i v i t y w i l l
systems t o e x t r a c t
the
associated
and m a t e r i a l s c o m p a t i b i l i t y c o n c e r n s .
t e n t a t i v e f u t u r e schedule.
174
e n e r g y from
mechanics,
effi-
Table 5 gives a
Table 5
Energy Extraction
Phase I
Act iv i ty
Define concept for energy extraction
Develop and test prototype hardware,
systems for magma energy extraction
Refine prototype and fabricate hardware for full-scale test
Install hardware on test well a n d
evaluate
Ia
FY
84
Ib
FY
85
-
Phase I 1
IIb
FY
88
Phase I 1 1
IIIal IIIb
FY
FY
90
89
IIIC
FY
91
ESTIMATED S C H E D U L E S AND B U D G E T S
The
program
is
currently
envisioned
as
an
effort, as shown by the schedules in Tables 1-5.
eight
As
year
the pro-
gram matures, its schedule will be impacted by research in the
other DOE programs discussed earlier.
reviews will provide a basis
for
In addition, annual peer
future program
directions,
including program termination if the R & D results suggest energy
extraction from magma is not viable.
Similarly, if the program
is successful, work on energy extraction and conversion a t the
shallow site will likely continue beyond the eighth year.
budget estimate is shown in Table 6.
A preliminary
estimate will be updated
This
annually as new information is ob-
tained.
SUMMARY
A
preliminary program plan has been developed to evaluate
the engineering
bodies.
feasibility of extracting
energy
from magma
The program covers eight years at a total estimated
cost of $50 M.
The program will have extensive interaction with other geothermal/geoscience
Scientific
research endeavors such a s the Continental
Drilling
Program.
Instrumentation
and
drilling
technology developments will also impact many other areas of
DOE responsibilities.
The Magma Energy Engineering Feasibility study results will
be reviewed annually and program directions and goals modified
appropriately.
Critiques and comments are welcome at all times.
176
Table 6
PROGRAM BUDGET TO DEVELOP THE
ENGINEERING FEASIBILITY OF MAGMA ENERGY
9
8
7
$10M
D SYSTEMS INTEGRATION
10
I
I
$10M
GEOPHYSICS
$8M
GEOCHEMISTRY/MATERIALS
ENERGY EXTRACTION
$7M
$7M
DRILLING TECHNOLOGY
6
5
4
3
2
1
0
FY84
IA
FY85
IB
FY86
IC
FY87
FY88
IIA
llB
TIME
FY89
IllA
FY90
llIB
FY91
IllC
Literature Cited
Re,
"Final Report--Magma Energy Research Project"
COlp, Jm
SAND82-2377, UC-66, Sandia National Laboratories/Albuquerque, NM
(1982), 36 pp.
Friedman, M. J. and others, "Strength and Ductility of Room-Dry and
Water Saturated Igneous Rocks at Low Pressures and Temperatures to
Partial
Me1 ting ,'I
SAND80-7159,
Sandia
National
Laboratories/Albuquerque, NM (1980).
Hardee, H. C., Trip Reports on Geophysical Means to Locate Magma
Bodies (1982).
Hardee, H. C., "Shallow Magma Eodies in the Western United States,"
Sandia memo (1983).
Smith, R. L. and H. R. Shaw, "Igneous-Related Geothermal Systems" i n
U.S. Geological Survey Cir. 726, Assessment of Geothermal Resources
of the United States-1975, (1975), p 58-83.
Smith, R. L. and H. R. Shaw, "Igneous-Related Geothermal Systems,"
in U.S. Geological Survey Cir. 790, Assessment of t h e Geothermal
Resources of the United States-1978, (1979) p . 12-17.
Traeger, R. K. and others, $"Drilling, Instrumentation and Sampling
Considerations for Geoscience" Studies of a Magma-Hydrothermal
Regime," SAND81-0800, Sandia National Laboratories/Albuquerque, NM
(1981), 51 pp.
178
BIBLIOGRAPHY
for
THE SCIENTIFIC FEASIBILITY OF
EXTRACTING ENERGY
FROM MAGMA BODIES
A.
Source Location
B.
Source Tapping
C.
Magma Characterization
D.
Energy Extraction
E.
Field Experiments
F.
Miscellaneous
G.
Project Reviews/Summaries
&
Definition
Sandia National Laboratories
179
A.
Source Location and Definition
SUMMARY OF RESULTS FROM ELECTROMAGNETIC AND GALVANIC SOUNDS ON
KILAUEA IKI LAVA LAKE, HAWAII, B. D. Smith, C. J. Zablocki, F. Frischknect,
and V. J. Flanigan, USGS Open File Report 77-59, 1977.
The purpose of this report is to summarize various electrical sounding
studies made on the Kilauea Iki lava lake and to present some of the
preliminary interpretations that resulted from the measurements. The
following discussion is not intended as a complete interpretation, but
is intended to summarize the major points made in an invited oral
presentation at the American Geophysical Union Fall Meeting held in
San Francisco, California, on December' 6, 1976. This paper was part of
a group of papers dealing with various geophysical studies recently made
on the Kilauea Iki lava lake.
FINE-MESH PASSIVE SEISMIC SURVEY OF KILAUEA 1x1 LAVA LAKE, J. L. C o l p ,
Sandia National Laboratories, EOS Trans., Am. Geophys. Union, V. 58,
No. 5, p. 311, May 1977.
A fine-mesh pas,sive seismic survey of Kilauea Iki lava lake was conducted as a follow-on to an earlier program of mapping of thermal
cracks. The objective of the fine-mesh survey was to delineate more
sharply the edge of the buried molten lava lense. The seismic array
consisted of six vertical motion geophones located fifty feet (15 m)
apart. This array was moved to a number of locations in the northeast
quadrant of K i l a u e a Iki. Data r e c o r d e d d u r i n g forty m i n u t e long observations indicated that discrete signals from single thermal cracks could
be observed. Data analysis gives a clear picture of the edge of the
molten lense based on the markedly increased number of thermal crack
events observed. Confirmation of the validity of these observations
awaits the planned drilling program.
UPMELTING IN MAGMA BODIES, H. C. Hardee, D. W. Larson, Sandia National
Laboratories, A. Herschman, Editor, Am. Assoc. Adv. Sci., Washington,
DC, p. 11, 1978, Proceedings of AAAS 144th National Meeting, Washington,
DC, February 12-17, 1978.
Analytical and numerical heat transfer calculations are used to show
that upward melting magma systems tend to be approximately equidimensional
with height to width ratios limited to around seven or less. This
agrees with observations on the magma body beneath Yellowstone which
appears to have a height/width ratio of five. Experiments run in the
laboratory with model simulants such as paraffin also confirm the
predictions. Injected magmas with very high height/width rat'ios appear
to be formed by a forced convection process which involves little, if
any, melting or natural convection. ,
SURFACE HEAT FLUX DISTRIBUTION ABOVE MAGMA SOURCES, H. C. Hardee, D. W.
Larson, Sandia National Laboratories, A. Herschman, Editor, Am. Assoc.
Adv. Sci., Washington, DC, p. 111, 1978, Proceedings of 144th National
Meeting, Washington, DC, February 12-17, 1978.
Analytical heat transfer techniques are used to calculate the surface
heat flux distribution above rectangular (dikes) and spherical magma
180
temperature, lowest viscosity and lowest density of olivine phenocrysts.
At 70 m one encounters a transition zone to a crystal-line mush, and
finally (between 80 and 95 m) solid basalt extending down to the preflow surface at a depth of 115 to 120 m.
SEISMIC PROPERTIES OF A SHALLOW MAGMA RESERVOIR IN KILAUEA IKI BY
ACTIVE AND PASSIVE EXPERIMENTS, K. Aki, B. Chouet, M. Fehler, G. Zandt,
R. Koyanagi, J. Colp, R. G. Hay, Journal of Geophysical Research,
Vol. 83, No. 85, pp 2273-2282, May 10, 1978
The use of multiple methods is essential for determination of seismic
properties of a complex structure like a partially frozen lava pond.
In our experiment with Kilauea Iki during March 1976, 1) the spatial
distribution of seismic events originating from the crust best defined
the lateral location of the magma lens, 2) the S waves transmitted
through the magma lens and dispersion of love waves generated by
explosive sources in the Iki floor constrained the S wave velocity
structure, and 3 ) P waves from explosions revealed an extremely low P
velocity zone below the crust. From love and S wave data we infer a
rather thin (less than 10 m) magma lens, which, in response to our weak
seismic signal, behaves like a viscous liquid with apparent viscosity
of about lo’ P and apparent shear velocity of about 0.2 km/s. Apparent
high viscosity at low stress level was reported by Shaw, et al., ( 1 9 6 8 ) ,
who made an in situ measurement of viscosity at Makaopuhi; Hawaii, and
attributed its possible source to the presence of vesicles. Liquid
containing vesicles apparently behaves like a bingham body: a solid
below the liquid above a threshold stress. The presence of vesicles
of a few volume percent in the melt can also reduce the apFarent bulk
modulus to as low as the apparent rigidity inferred from lcve and S wave
data. The P velocity of about 0.3 km/s is possible in the melt with
5 % vesicles. The observed refraction data require the P velocity in
the lower crust to be as low as 0.9 km/s. This low velocity may be
attributed to dry cracks unfilled with liquid magma.
A CRITICAL ASSESSMENT OF GEOPHYSICAL SENSING EXPERIMENTS ON KILAUEA IKI
LAVA LAKE, SAND77-0828, J. F. Hermance, D. W. Forsythe, and J. L. Colp,
Sandia National .Laboratories.
The Hawaiian lava lake in the Kilauea Iki pit crater, resulting from the
1959 summit eruption of Kilauea volcano, has served as a natural
laboratory for the continuing study of the petrology, rheology, and
thermal history of ponded molten basalt flows in the field environment.
During 1975 and 1976, a series of electromagnetic and seismic experiments were coordinated, and in some cases supported, by the Magma
Energy Program at Sandia National Laboratories in an attempt to define
the in-situ geophysical properties and the configuration of the molten
lava core as closely as possible. This effort involved workers from
the United States Geological Survey (USGS), University of Texas,
Massachusetts Institute of Technology (MITI, Sandia National Laboratories,
and Brown University. Drilling and geophysical experiments in 1976
suggested that the solidified crust of the lava lake had a cool,
resistive surface layer, undersaturated with water to a depth of 5 metres.
A warm, wet layer containing appreciable water and/or steam was essentially
isothermal (100OC) to 33 metres. From 33 to 4 5 metres the temperature
climbed rapidly (from 100 to 1,O7O0C) until a thin plexus of molten sills
was encountered, interbedded with solid layers. Below this ( 5 0 metres)
was apparently a layer having the highest temperature, lowest viscosity,
181
THERMAL TECHNIQUES FOR LOCATING AND CHARACTERIZING BURIED MAGMA BODIES,
H. C. Hardee and D. W. Larson, Sandia National Laboratories, Hawaii
Symposium Proceedings on Intraplate Volcanism and Submarine Volcanism,
Hilo, Hawaii, July 16-22, 1979.
The surface heat flux distribution resulting from emplaced magma bodies
can be used to help characterize the magma source. Closed-form analytical
solutions for the heat transfer from various idealized magma geometries
(dikes, sills, and spheres) are obtained using either the SchwarzChristoffel transformation or the "method of images." Comparison of
these analytically determined heat flux distributions with field data
from active geothermal areas at Yellowstone, Avachinsky volcano,
Kilauea Iki, and the Cos0 geothermal area indicates that these fields
may be conduction dominant, at least over certain depths. The
Yellowstone comparison indicates that the top of a convectins hydrothermal zone exists at a depth of around 1 km and this agrees with
the findings of other investigators who base their conclusion on
seismic and drilling data. The Avachinsky comparison indicates that a
magma chamber exists at a depth of 4.8 km and this agrees with estimates by Sergey Fedatov for a spheroidal magma chamber at 5 km depth.
TEMPERATURE MEASUREMENTS IN THE CRUST OF KILAUEA IKI LAVA LAKE, H. C.
Hardee, Sandia National Laboratories, Proceedings of Symposium on
Intraplate Volcanism and Submarine Volcanism, Hilo, Hawaii, July 16-22,
1979.
The crust of Kilauea Iki lava lake currently consists of an upper porous
two-phase convection zone 41 m thick and a lower conduction zone 12 m
thick extending to the melt. The crust has been solidifying at a near
constant rate of 6.7 x 10" m/s for the past twelve years. The thickness
of the lower conduction zone has been relatively constant during this
period. Temperature profiles 'in the lower conduction zone have a curvature that can be explained in terms of a moving solidification-front
conduction solution. Recent temperature profiles show the predicted
reversal of curvature where solidification has ceased.
COMPARATIVE ASSESSMENT OF FIVE POTENTIAL SITES FOR HYDROTHERMAL-MAGMA
SYSTEMS: SUMMARY, DOE/TIC-11303, November 1980.
An objective of the Thermal Regimes portion of the Continental Scientific
Drilling Program (CSDP) is the development of a fundamental understandina
of energy transport within and between hydrothermal and magma systems.
A comparative assessment of five potential hydrothermal-magma sites for
this facet of the Thermal Regimes part of the CSDP has been prepared
for the DOE Office of Basic Energy Sciences. Four DOE laboratories
(Los Alamos National Laboratory, Lawrence Berkeley Laboratory, Lawrence
Livermore National Laboratory, and Sandia National Laboratories) participated in this study. The five sites are: The Geysers-Clear Lake,
California: Long Valley, California, Rio Grande Rift, New Mexico;
Roosevelt Hot Springs, Utah: and Salton Trough, California. This site
assessment study has drawn together background information (geology,
geochemistry, geophysics, and energy transport) on the five sites as a
preliminary stage to site selection. Criteria for site selection are
that potential sites have identifiable, or likely, hydrothermal systems
and associated magma sources, and that important scientific questions
can be identified and answered by deep scientific holes.
182
MULTIPLE SCALE CONVECTION IN THE EARTH'S MANTLE: A THREEDIMENSIONAL STUDY, Charles'R. Carrigan, Sandia National
Laboratories and Bullard Laboratories, Cambridge University,
Science 215, pp 965-967, February 1982.
Recent laboratory experiments suggest that a convective regime
characterized by two length scales of motion is a reasonable
model for circulations in the earth's upper mantle. The flows
of largest horizontal scale represent a likely plate driving
mechanism required by some theories of plate tectonics. It
is also argued that the superposed large and small scales,
within the context of current geochemical and mechanical
theories, can contribute to the heterogeneity of the upper
mantle and crust -- a contradiction of the often assumed role
of convection as a mechanism for mixing the mantle.
VESTICULATION OF MAFIC MAGMA DURING REPLENISHMENT OF CRUSTAL
MAGMA RESERVOIRS, J. C. Eichelberger, Sandia National Laboratories, Nature 288, (1980) pp 446-450.
Mafic inclusions in andesitic and dacitic lavas and in equivalent plutonic rocks have been interpreted as cumulates from
fractional crystallization, restites from deep crustal melting
and rapidly crystallized mafic magmatic material generated
during magma mixing. The implications of these interpretations
for both magmatic and crustal evolution differ dramatically.
I have previously argued that the inclusions result from magma
mixing on the basis of their texture, bulk composition and
phase composition. A new observation is that the inclusions
exhibit high vesicularity and consequently have a lower bulk
density than their hosts. This property is consistent with
generation of the inclusions by magma mixing, and may play an
important part in the evolution of large magma reservoirs
within the upper crust.
PERIODIC DOWNHOLE SEISMIC SOURCES, SAND81-1891, H. C. Hardee,
Sandia National Laboratories, Geophysical Prospecting, Vol. 31,
pp 57-71 (1983).
Downhole periodic seismic sources offer a number of advantages
over conventional sources including: good economics, high temperature applications, effective coupling of seismic waves
directly into the region of interest, and sophisticated signal
processing possibilities.
183
magma energy studies. Emphasis is centered on studies of magma generation, ascent, emplacement, evolution, and surface or near-surface
activity. An indexed reference list is also provided to facilitate
future investigations.
SOLIDIFICATION IN KILAUEA IKI LAVA LAKE, Harry C . Hardee, Sandia
National Laboratories, Journal of Volcanology and Geothermal-Research
7 (1980) 211-223.
The crust of Kilauea Iki lava lake currently consists of an upper
porous two-phase (water/steam) convection zone 41 m thick and a lower
conduction zone 12 m thick extending to the melt. Although the solidification of the crust initially followed the classical square root of
time law, the crust has been solidifying at a constant rate of 6.7 x
10" m/s for the past twelve years. The thickness of the lower zone of
the crust also appears to have reached a constant value of 12 m. A
moving solidification front solution is developed which shows that the
constant solidification rate and constant thickness of the lower crust
zone are natural outcomes of a heat balance between the two zones of the
crust. Observed temperature profile curvature from borehole temperature measurements in the lake can be explained in terms of the solidification front solution. The solution and temperature profile data
can be used to estimate an average in-situ permeability of 0.30 darcy
for the upper zone of the crust which agrees well with measured values.
SOURCE LOCATION SURVEY, SAND82-0219, H. C. Hardee, J. C.
Dunn, J. L. Colp, Sandia National Laboratories.
MAGMA
A survey of industry/university geophysicists was conducted to
obtain their opinions on the existence of shallow (less than 10
km from surface) magma bodies in the western conterminous
United States and methods for locating and defining them.
Inputs from 35 individuals were received and are included.
Responses were that shallow magma bodies exist and that existing geophysical sensing systems are adequate to locate them.
THE RESONANT ACOUSTIC PULSER--A CONTINUOUS-FREQUENCY MARINE
SEISMIC SOURCE, H.. C. Hardee, R. G. Hills, Sandia National
Laboratories, SAND80-2568JI Geophysics, in press.
is described which produces a continuous low frequency (10-100 Hz) harmonic signal. High acou'stic
power levels (approximately 20 kW) are reached by using a
resonant system. The seismic source has been successfully
tested in lake and ocean environments.
A marine seismic source
184
B.
Source Tapping
DRILLING INTO MOLTEN ROCK AT KILAUEA IKI, John L. Colp, Sandia
National Laboratories, Reginald T. Okamura, USGS, Transactions,
Geothermal Resources Council, Vol. 2, July 1978, Hilo, Hawaii.
The Sandia Magma Energy Research Project is assessing the scientific
feasibility of extracting energy directly from buried circulafing
magma resources. One of the tasks of the project is the study of geophysical measuring systems to locate and define buried molten rock
bodies. To verify the results of a molten rock sensing experiment
performed at Kilauea Iki lava lake, it is necessary to drill a series
of holes through the solid upper crust and through the molten zone
at that location. Thirteen holes have been drilled in Kilauea Iki;
eleven by other groups and two by Sandia. The results achieved during
the drilling of the two Sandia holes have indicated that the molten
zone in Kilauea Iki is not a simple, relatively homogeneous fluid body
as expected. The encountering of an unexpected, unknown rigid obstruction 2.5 ft below the crust/melt interface has led to the conceptual
development of a drilling system intended to have the capability to
drill through a hot, rigid obstruction while the drill stem is immersed
in molten rock. The concept will be field tested in Kilauea Iki in the
summer of 1978.
BOREHOLE STABILITY IN IGNEOUS ROCKS AT LOW PRESSURES AND TEMPERATURES
TO PARTIAL MELTING, M. Friedman, J. Handin, N. G . Hibbs, and J. R.
Lantz, Center f o r Tectonophysics, Texas AsM University, under contract
to Sandia National Laboratories, Proceedings of Symposium on Intraplate
Volcanism and Submarine Volcanism, Hilo, Hawaii, July 16-22, 1979.
Energy extraction from magma requires stable boreholes at relatively
10 km) in rocks at temperatures of the order of
shallow depths
1OOO'C.
Accordingly, the failure strengths, permanent strains, and
associated deformation mechanisms of room-dry andesite, basalt,
granodiorite, and obsidian are determined at temperatures to partial
melting ( > lO5O0C), at confining pressures of 0 and 50 MPa, and a
-The strength reductions of the crystalline
strain rate of l O " / s .
rocks are more or less linear until they steepen suddenly with approach
to melting. When that occurs, strengths vanish and deformations
become quasiviscous with equivalent viscosities of the order of lo' to
10' N
s/m2. The obsidian is stronger than the crystalling rocks to
6 0 0 ' C where g l a s s softening begins and strength goes to zero at 800'C
( 0 = 10" N
s/m2. - All rocks are brittle throughout the entire
temperature range until melting or softening occurs. Shortenings at
failure are 2 percent or less unconfined, and 6 percent at most, at
50 MPa.
WATER JET DRILLING IN LIQUID LAVA, J. C. Dunn and P. C. Montoya, Sandia
National Laboratories, Proceedings of Symposium on Intraplate Volcanism
and Submarine Volcanism, Hilo, Hawaii, July 16-22, 1979.
Two new concepts for entering and drilling into molten rock under local
fluid pressure were tested in the Xilauea Iki lava lake during January,
1979. Previous attempts to drill with conventional techniques in
liquid lava at Kilauea Iki failed, primarily for two reasons. First,
standard water pressure is below local formation pressure of the lava.
185
DRILLING INTO MOLTEN ROCK--AN UPDATE, John L. Colp, Sandia
National Laboratories, SAND81-0250, Proceedings 1981 Arc
Volcanism Symposium, International Association of Volcanology
and Chemistry of Earth's Interior, August 28-September 9, 1981,
Tokyo, Japan.
The Sandia .Magma Energy Research Project is assessing the
scientific feasibility of extracting energy directly from
buried circulating magma resources (Colp and Stoller, 1981).
One of the tasks of the project is the study of geophysical
measuring systems to locate and define buried molten rock
bodies. To verify the results of molten rock sensing experiments performed at Kilauea Iki lava lake, it was necessary to
drill a series of holes through the solid upper crust and
through the molten zone at that location.
THERMAL GEOPHYSICAL TECHNIQUES FOR LOCATING MAGMA, H. C. Hardee,
Sandia National Laboratories, SAND81-0111, Proceedings 1981
Arc Volcanism Symposium, International Association of Volcanology
and Chemistry of Earth's Interior, August 28-September 9, 1981,
Tokyo, Japan.
Thermal geophysical techniques are useful in defining the
depth, areal extent, or state of magma bodies beneath volcanic
and geothermal areas. In areas where hydrothermal activity is
small, conduction techniques can be used to estimate the size
and depth of magma bodies. Analytical conduction solutions have
been obtained for simple magma geometries (dikes, sills, spheres)
and the results compare favorably with field data from Cos0
geothermal area, Yellowstone, and Avachinsky volcano where magma
bodies are suspected at depths on the order of 5 km. In areas
where hydrothermal circulation cannot be ignored, conduction
techniques can still be used by taking downhole measurements
below the hydrothermal zone. Such techniques have been used in
lava lakes in Hawaii and Iceland to predict the areal extent
and solidification rate of the underlying magma. Accurate heat
flow measurements can be made within hydrothermal circulation
zones, although with difficulty. Heat flow in such zones is
primarily dependent on the permeability of the zone rather than
the condition of the underlying magma. Such measurements do
not readily yield information about the depth of the magma
although these measurements can be used to determine the areal
extent of the magma body.
186
C. Magma Characterization
EXPERIMENT PLAN FOR CHARACTERIZATION OF THE PROPERTIES OF MOLTEN ROCK
AT ATMOSPHERIC AND ELEVATED PRESSURES: MAGMA ENERGY RESEARCH PROJECT,
5AND78-2227, P. J. Modreski, Sandia National Laboratories.
Knowledge of the properties of molten rock (maqma) is of importance to
the Magma Energy Research Project of Sandia National Laboratories.
Facilities have been set up at Sandia to s t u z y the physical properties,
chemistry, and corrosive nature of magma to 16OO0C from atmospheric
pressure to 4 kbar (400 ma). Experiments at atmospheric pressure are
being done in the presence of multicomponent gas mixtures to control
the chemical activities of oxygen and sulfur. The high-pressure
apparatus includes cold-seal small-volume pressure vessels (to llOOoc
and 1 kbar). The large vessel contains a number of penetrations for
electrical leads and pressure lines, and is linked to a computer for
data acquisition and control of experiments. Water and other dissolved
volatiles (Con, CO, S02, S p , HIS, HCL, HF) have significant effects on
all the properties of magma, and these effects will be studied in the
high-pressure apparatus. Phase equilibria, viscosity, electrical
conductivity, and materials compatibility will be the first properties
to be examined under pressure. This report includes a review of the
nature and chemical basis for the effects of dissolved volatiles on
these properties of magma.
EVALUATION AND RESTORATION OF THE 1970 VOLCANIC GAS ANALYSES FROM
MOUNT ETNA, SICILY, T. M. Gerlach, Sandia National Laboratories,
Journal of Volcanology and Geothermal Research 6 (1979) 165-178.
The 1970 Mount Etna volcanic gas analyses (Huntingdon, 1973) are anono
the most reduced volcanic gas samples ever reported. They contain
20-40% H2, 2-3.5% CO, and 2-5% HzS. Calculated oxygen fugacities for
most of the analyses are well below quartz-fayalite-magnetite, several
are more measured by Sat0 and Moore (1973) in the.gas-streams of the
collection sites at the time the samples were taken. The analyses show
no similarity to calculated equilibrium compositions at any temperature. Deviations between analytical and equilibrium compositions
indicate the gases have undergone extensive reduction involving mainly
loss of oxygen. There a l s o is limited evidence of s u l f u r l o s s . The
reduced analyses are not the products of unusually reduced lavas, but
originated from reactions of the erupted gases with the metal sampling
device used in the collection procedure. The oxygen deficiencies of
the analyses have been restored using the atomic hydrogen, carbon and
sulfur data of Huntingdon and the oxygen fugacity data of Sat0 and
Moore. The restored analyses are much more representative of the
erupted gases which were remarkably rich in COZ (15-35%) and 502
(15-35%), and they show relatively steady compositions at each collection
site over periods of observation ranging from hours to days.
COMPOSITIONS OF GASES COLLECTED DURING THE 1977 EAST RIFT ERUPTION,
KILAUEA, HAWAII, E. J. Graeber, P. J. Modreski and T. M. Gerlach,
Sandia National Laboratories, Journal of Volcanology and Geothermal
Research, 5 (1979) 337-344.
Several high-temperature (950-1O6O0C) gas samples were collected with
a new sampling device from lava flows and a vent during the September
1977 Kilauea eruption. After removal of atmospheric contaminants
187
VOLCANIC GASES AND COMPATIBILITY WITH PURE METALS, T. M. Gerlach,
Sandia National Laboratories, Proceedings, Hawaii Symposium on Intraplate Volcanism and Submarine Volcanism, Hilo, Hawaii, July 1979.
Materials incompatibility is a potential problem confronting schemes for
energy extraction from magma bodies. Chemical incompatibility between
magmatic volatiles and metals is of particular concern. The purpose of
this study is to describe the chemical characteristics of magmatic
gases, inferred from existing volcanic gas collections, as a prelude to
assessing metal incompatibilities.
Existing "high quality" volcanic gas samples are restricted to approximately 100 high temperature ( > 95OOC) collections obtained in source
regions of tholeiitic and alkaline mafic lavas. These samples have
erratic compositions which compromise attempts to characterize the
chemistry of magmatic gases. Detailed studies of the analyses have
identified several modifications, in addition to atmospheric contamination, which have been imposed on the samples during or after collection.
THE CALCULATION AND USE OF CVD PHASE DIAGRA!!S WITH APPLICATIONS TO THE
Ti-B-C1-H SYSTEM 1200K-800K, E. Randich and T. M. Gerlach, Sandia
National Laboratories, SAND80-0308.
A simple method for calculating multi-component gas-solid equilibrium
phase diagrams for chemical vapor deposition.(CVD) systems is presented.
The method proceeds in three steps: determination of stable s o l i d
assemblages, evaluation of gas-solid stability relations, and calculation of conventional phase diagrams using-a free energy minimization
technique. The phase diagrams can be used to determine 1) bulk compositions and phase fields accessible by CVD techniques, 2) expected
condensed phases for various starting gas mixtures, and 3) maximum
equilibrium yields for specific CVD process variables. The three step
thermodynamic method is used to calculate phase diagrams for the
example CVD system Ti-B-C1-H at 1200K and 800K. Examples of applications
of the diagrams for yield optimization and experimental accessibility
studies are presented and discussed. Experimental verification of phase
field boundaries at 1200K, H/C1 = 1 and H/C1 = 5 confirms the calculated
boundaries and indicates that equilibrium is nearly and rapidly approached
in this system under laboratory conditions.
DEVELOPMENT OF HIGH TEMPERATURE VISCOSITY MEASUREMENT TECHNIQUE,
SAND80-0641, Sandia National Laboratories, R. P. Wemple, W. F.
Hommetter, and C. J. Greenholt, April 1980.
Viscosity measurements with magmatic rock at high temperatures and
occasionally at elevated pressures are nontrivial problems. This
report details the conception, development, and testing of : 1) an
electromagnetic viscometer, and 2 ) an x-ray technique. Both methods
employ a falling metallic sphere in the melt and provide real-time data.
Initial testing of the electromagnetic viscometer was performed at one
bar and from 700-13OO0C. Follow-on experiments with this viscometer
were carried out at 1 bar and 0 . 4 6 6 kbar ( 6 . 8 kpsi) aron up to 125OOC
at the Sandia Magma Energy Research Test Facility. The x-ray method was
tested entirely at one bar and up to 1325OC. A simultaneous test series
with both methods was performed at one bar.
188
INVESTIGATION OF VOLCANIC GAS ANALYSIS AND MAGMA OUTGASSING FROM ERTA
:ALE LAVA LAKE, AFAR, ETHIOPIA, T. M. Gerlach, Sandia National Laboratories,
J. Volc. and Geoth. Res., V. 7 , 415-441, 1980.
The analyses of 18 volcanic gas samples collected over a tworhour period
at 1075OC from Erta Ale lava lake in December 1971 and of 18 samples
taken over a half-hour period at 1125OC to 1135OC in 1974 display moderately
to intensely variable compositions. These variations result from imposed
modifications caused by 1) atmospheric contamination and oxidation,
2 ) condensation and re-evaporation of water durinq collection, 3) analytical errors, and 4). chemical reactions between the erupted gases and a
steel lead-in tube.
COMPOSITIONS AND PROPORTIONS OF MAJOR PHASES IN THE 1959 KILAUEA IKI
LAVA LAKE IN DECEMBER 1978, W. C. Luth and T. M. Gerlach, Sandia National
Laboratories, EOS Transactions, American Geophysical Union, Volume 61,
Number 46, November 11, 1980, 1980 AGU Fall Meeting.
Twelve element quantitative electron microprobe analyses on phases in
30 samples of 3 drill holes penetrating magma were used to define 4
zones in the lava lake. Depths to zones vary due to a biconvex magma
zone. At 285 m north of the center the zones are: Upper Curst (UC),
0-50.5 m; Upper Magmatic Transition Zone (UMTZ), 50.5-53.5 m; MaTla Zone
(MZ), 53.5-61 m; Lower Magmatic Transition Zone (LMTZ), 61-63(?) m. The
lower crust was not penetrated in the drilling program. Glass compositions define smooth continuous paths on oxide variation and AFM diagrams,
from basaltic in the LMTZ and MZ to rhyolitic in the UMTZ and UC. Glass
compositions are constant in composition in the MZ and LMTZ although
abundance decreases from 35% in the MZ to < 15% in the LMTZ. Glass
abundance decreases in the UMTZ and UC (5%) accompanying the major
compositive change. Olivine compositions are essentially constant
(To (Wt72) in the MZ and LMTZ, with a range Prom € 0 7 0 - 7 5
and no significant compositional difference between phenocrysts and microphenocrysts.
Mean compositions become less Fo-rich and show greater dispersion about
the mean in the UMTZ and UC. Olivine abundance varies over a wide
(20-47%) range reflecting in situ crystallization crystal settling, and
sub-solidus recrystallization. Plagioclase abundance is constant
(15 vol % ) in the MZ and LMTZ, increasing to 30-35 vol % in the UMTZ
and UC. Mean plagioclase compositions decrease from A n y , , to An70 (wt)
with decreasing depth in the LMTZ and MZ. Mean compositions become more
sodic ( A n s s ) and compositional dispersion increases in the UMTZ and UC.
Clinopyroxene compositions are invariant with respect to composition in
the LMTZ, MZ, UMTZ, and lower part of the upper crust.
MASS BALANCE DIFFERENTIATION MODELS FOR THE 1959 KILAUEA IKI LAVA LAKE,
T. M. Gerlach and W. C . Luth, Sandia National Laboratories, EOS Transactions, American Geophysical Union, Volume 61, Number 46, November 11,
1980, 1980 AGU Fall Meeting.
Unweighted least squares mass balance differentiation models for
Kilauea Iki lava lake have been calculated from published glass and lava
compositions ( S 7 , MURATA AND RICHTER, 1966) and new data for mineral,
glass and bulk compositions of 11 samples (Chambers, et al., Luth,
et al., this volume) from a recent drill hole penetrating a 11 m thickness of magma 285 m north of the lake center. The initial magma for the
models was S 7 , which corresponds closely to the mean lava lake composition. Rocks of the Upper Magmatic Transition Zone (UMTZ, 50.5-53.5 m)
189
PERMEABLE CONVECTION ABOVE MAGMA BODIES, Tectonophysics, Vol.
8 4 , pp 1 7 9 - 1 9 5 8 1982, H. C. Hardee, Sandia National
Labor a tor i e s
.
Thermal convection above large sha1lo.w magma bodies in the
crust is treated as a one-dimensional bottom-heated convection
process in permeable media. Solutions for single-phase convection are briefly reviewed and a solution is developed for
two-phase permeable convection in bottom heated media. Heat
flow measurement techniques are discussed for permeable geologic zones above magma bodies and these techniques g i v e consistent results for solidifying lava lakes i n Hawaii (Kilauea
Iki, q = 260 kW/m*) and Iceland (Heimaey, q = 470 kW/m*).
The heat loss from a magma body is a strong function of the
permeability when a two-phase convection zone occurs above the
magma body, and the heat loss is independent of the thickness
of the two-phase convection zone. In steady-state two-phase
convection zones, where permeability does-not vary appreciably
with depth, convective heat flow restrictions tend to limit the
maximum saturation temperatures at depth to around 25OOC -- an
effect observed in many geothermal steam fields. A conduction dominated transition zone tends to occur between the twophase zone and the magma body and the thickness of this transition zone may readily range from a few meters to several
kilometers, depending on the permeability.
INCIPIENT MAGMA CHAMBER FORMATION AS A RESULT OF REPETITIVE
INTRUSIONS, Bulletin Volcanologique, Vol. 4 5 - 1 , H. C. Hardee,
Sandia National Laboratories.
A n analytical solution for periodic magma intrusions in conduits was developed to study the onset of shallow magma chamber
formation. The solution is based on determining when a repetitive series of intrusions can cause the wall rock of a conduit
t o reach its melt temperature. The results show that magma
chamber formation in conduits i s , a strong function of the
volume rate of intrusion and that magma chamber formation is
likely when the intrusion rate exceeds
km3/yr which
agrees with observations by other investigators. Once this
critical value of intrusion rate is reached, magma chambers are
likely to begin forming after only a few intrusive pulses (less
than ten). Results for both cylindrical conduits and dikes
show that cylindrical conduits are more favorable for the formation of shallow magma chambers.
190
I_
KILAUEA IKI LAVA LAKE: GEOPHYSICAL CONSTMINTS ON PRESENT
(1980) PHYSICAL STATE, Journal of Volcanology and Geothermal
Research, Vol. 13, No. 1-2, pp 31-61, 1982, J. L. Colp, Sandia
National Laboratories, John F. Hermance, Brown University.
model is presented representing the present-day (1980) configuration of Kilauea Iki lava lake. This interpretation is a
synthesis of the results of drilling, thermal modeling, petrology and geophysical sensing experiments. According to this
model, the crust of the lava lake is characterized by a thick
two-phase convection-dominated zone and a single-phase (steam)
dry-out zone. Geophysical measurements (namely electromagnetic
sounding experiments) suggest the presence of an anomalous zone
which is significantly thicker (greater than 30 m thick at 40 m
depth) than the zone of melt-slush (10 m thick at 5 4 m depth)
seen in petrological investigations of the drill core. This
suggests that the geophysically active zone is caused by physical processes not directly related to the presence of magma or
that the magma is thinly disseminated over a broader region
than indicated in petrological inspections of recent (1979)
drill cores. We cannot at this time rule out ( o r support) the
possibility of a plexus of segregation veins distributed
throughout the high-temperature region of the lake, particularly below the melt slush region where information is sparse.
A
COMMENTS ON PERMEABLE CONVECTION ABOVE MAGMA BODIES, H. C.
Hardee, Sandia National Laboratories, Tectonophysics, in press.
The lava lake calculations by Hardee (1982) require the presence of water. This water may well have reached the lava lake
in the form of rainfall or condensation. In addition to the
presence of water, the permeability and thermal properties of
lava and water are used to evaluate the rate of two-phase conThis calculation agrees well
vection heat flow (268 W/m2).
with two independent heat flow calculations - 2 5 7 W/m2 based
on temperature gradient measurements in the non-convecting
transition zone and 2 4 3 W/m2 based on the rate of solidification as determined from repeatedly drilling to the melt interface over a number of years. In addition, the permeability was
determined in an independent measurement in a packed-off pressurized borehole. The two-phase convective heat flow analysis
used by Hardee, which showed that heat flow is a function of
permeability, has been verified by careful laboratory experiments by the author and by independent laboratory measurement
by others. Finally, the lava bodies at Kilauea Iki, Hawaii,
and Heimaey, Iceland, show similar solidification behavior and
rates and these bodies are of similar material, age and permeability. The rainfall is considerably different for these two
regions however. Kilauea Iki lava lake is situated in the Ohia
Rain Forest and receives considerably more rainfall than
Heimaey. Yet the solidification rate at Heimaey, instead of
being much smaller than that of Kilauea Iki, is actiially twice
191
RESTORATION OF NEW VOLCANIC GAS ANALYSES FROM -BASALTS OF THE
AFAR REGION: FURTHER EVIDENCE OF C02-DEGASSING TRENDS, T. M.
Gerlach, Sandia National Laboratories, Journal of Volcanology
and Geothermal Research, Volume 10, No. 1-3 (19811, p. 83.
The restored compositions for approximately 70 new analyses
reported recently for Erta Ale lava lake (GeGuern, et al.,
1979) are in good agreement with restored compositions (Gerlach,
1979A) based on previously published data. The results confirm
earlier indications that gas collections taken at different
times from the lava lake are related principally to variations
in CO2 content. Restored compositions for gas samples collected
in the final stages of a November 1978 Ardoukoba eruption along
the Asal Rift spreading axis resemble the Erta Ale gases
except for a much lower C02 content. The Ardoukoba gases fall
close to a CO2-decreasing controlline for gases with initial
compositions similar to the 1971-73 Erta Ale gases. These
results suggest that gases released from basaltic lava along
zones of crustal spreading follow compositional trends dominated by changes in C02 content.
CHEMICAL CHARACTERISTICS OF THE VOLCANIC GASES
LAVA LAKE AND THE GENERATION OF CH4-RICH FLUID
ALKALINE ROCKS, T. M. Gerlach, Sandia National
Journal of Volcanology and Geotheram Research,
FROM NYIRAGONGO
INCLUSIONS IN
Laboratories,
8(1980)177-189.
Methods used previously to remove compositional modifications
from volcanic gas analyses for Mounta Etna and Erta' Ale lava
lake have been employed to iestimate the gas phase composition
at Nyirangongo lava lake, based on samples obtained in 1959.
H 2 0 data were not reported in 11 of the 13 original analyses.
The restoration methods have been used to estimate the H20
contents of the samples and to correct the analyses for atmospheric contamination, l o s s of sulfur and for pre- and postcollection oxidation of H2S, S2, and H2. The estimated gas
compositions are relatively Con-rich, low in total sulfur and
reduced. They contain approximately 35-50% C02, 45-55% H20,
1-2% SO2, 1-2% H2, 2-3% CO, 1.5-2.5% H2S, 0.5% S2, and 0.1% COS
over the collection temperature range 1020 to 960OC. The oxygen
fugacities of the gases are consistently about half an order of
The low total sulmagnitude below quartz-magnetite-fayalite.
fur content and resulting low atomic S/C of the Nyiragongo
gases appear to be related to the relatively low f O 2of the
cyrstallizing lava. At temperatures above 8OOOC and pressures
of 1-1.5 kbar, the Nyiragongo gas compositions resemble those
observed in primary fluid inclusions believed to have formed
at similar temperatures and pressures in nephelines of intrusive alkaline rocks. Cooling to 3OO0C, with f O 2 buffered by
the rock, results in gas conlpositions very rich in CHI,
at 1200 K, H/C1 = 1 and H/C1 = 5, confirms the calculated
boundaries and indicates that equilibrium is nearly and rapidly
approaches in this system under laboratory conditions.
192
D. Energy Extraction
EXTRACTION OF HEAT FROM MAGMAS BAsED.ON HEAT TRANSFER MECHANISMS,
H. C. Hardee, D. W. Larson, Sandia National Laboratories, J. Volcanol.
Geotherm. Res., V. 2 , No. 2 , pp. 113-144, July 1977.
Analytical heat transfer calculations are used to relate geoloqical
surface evidence to conditions that should exist in magma chambers for
the purpose of improving estimates of possible commercial heat extraction
rates. These calculations indicate that an upward-melting magma system
necessarily is approximately equidimensional and that injected magmas
with very high aspect (L/D) ratios are likely formed’by a forced
intrusion process which involves little if any melting or natural
convection. Calculations along with surface heat flow measurements
suggest that steady-state heat extraction rates for emplaced heat
exchangers in currently suspected shallow magma chambers will probably
be below 10 kW M-2, a value that is low by engineering standards.
THE EXTRACTION O F HEAT FROM MAGMA BODIES, H. C. Hardee, Jr., Sandia
National Laboratories, A. Herschman, Editor, Am. Assoc. Adv. Sci.,
Washington, DC, p. 111, 1978, Proceedings of AAAS 144th National
Meeting, Washington, DC, February 12-17, 1978.
Analytical heat transfer techniques are used to relate geological surface
evidence and observations to conditions that’are likely to exist in
magma chambers. An experimeptal heat exchanger was tested in a molten
lava source heated by an induction furnace. Design work has been
started on a prototype long tube heat exchanger. This information is
being used to make estimates f o r commercial heat extraction rates.
Calculations and surface heat flow measurements indicate that the
steady-state heat extraction rates for shallow convecting magma chambers
with low superheat will probably be on the order of 10 kw/m2 or less and
a lower limit of around 1 kw/m2 will occur for conduction dominant
magma chambers. Preliminary cost comparisons indicate that magma power
would be competitive with conventional power plants at magma heat
extraction rates of 4 kw/m2 or more.
HEAT-TRANSFER’MEASUREMENTS IN 1977 KILAUEA LAVA FLOW, H. C. Hardee,
Sandia National Laboratories, Transactions, American Geophysical Union,
Vol. 59, No. 4 , p. 311, 1978.
The 1977 Kilauea eruption (September-October 1977) produced a river of
basaltic lava which flowed for several days. During this eruption an
experiment was performed in which a heat transfer probe, containing
two heat flux gauges, was inserted into the lava river about 5 0 meters
from the Puu Kiai vent. Five minutes of data were obtained during the
test and heat fluxes were recorded ranging from 200 kW/m2 down to
10 kW/m2. The measurements correlated well with theoretical calculations
of heat flux based on the best current knowledge of lava properties.
Analysis of the data indicated that vesicles and interface contact gaps
were likely present in the lava crust that solidified on the surface of
the heat flux gauges. There was also an indication that one of these
heat flux gauges may have been approaching a convective heat transfer
limit around 5 kW/m near the end of the test. A test with a second
thermal probe indicated that the lava had an effective thermal diffusivThis
ity of 1.88 x 10’’ cm2/s in the temperature range of 900-1:100°C.
value of diffusivity is consistent with currently known lava properties
193
magmas, t h e h e a t e x t r a c t i o n r a t e i s l i m i t e d by c o n d u c t i o n t o a b o u t
1 kw/m2 f o r r e a s o n a b l e p l a n t - l i f e a s s u m p t i o n s . ?in economic break-even
p o i n t f o r c l o s e d h e a t exchanger systems o c c u r s a t h e a t t r a n s f e r r a t e s
a r o u n d 5 kw/m2. I t t h e r e f o r e a p p e a r s t h a t o n l y t h e b e t t e r b a s a l t i c
magmas m i g h t p r o v e e c o n o m i c a l f o r h e a t e x t r a c t i o n w i t h c l o s e d , h e a t
exchanger systems.
V a r i o u s open h e a t e x c h a n g e r s y s t e m s c o u l d improve t h e e f f e c t i v e h e a t
The open
e x t r a c t i o n r a t e by o n e and p o s s i b l y t w o o r d e r s o f magnitude.
h e a t e x c h a n g e r s y s t e m s a r e u s u a l l y b a s e d i n p r i n c i p l e o n some means of
i n c r e a s i n g t h e e f f e c t i v e s u r f a c e a r e a o f t h e e x c h a n g e r . One method i s
t o form a l a r g e p o r o u s c r u s t a r o u n d t h e e x c h a n g e r and p a s s a h e a t
t r a n s f e r f l u i d t h r o u g h t h i s p o r o u s r e g i o n . The " h u f f a n d p u f f " c o n c e p t
is o n e s u c h example where t h e h e a t t r a n s f e r f l u i d is a l t e r n a t e l y
i n j e c t e d and removed from t h e p o r o u s r e g i o n . T h i s c o n c e p t i s somewhat
s i m i l a r t o a t e c h n i q u e u s e d i n t e r t i a r y o i l r e c o v e r y where a working
f l u i d i s pumped i n t o a p o r o u s c a v i t y and h e a t e d o i l i s removed
periodically.
ENERGY EXTRACTION FROM CRUSTAL MAGMA B O D I E S , SAND82-1386A,
J. C. Dunn, S a n d i a N a t i o n a l L a b o r a t o r i e s , ASME-JSME Thermal
E n g i n e e r i n g J o i n t C o n f e r e n c e , March 20-24, 1 9 8 3 , H o n o l u l u ,
Hawaii.
T h e DOE-funded
S a n d i a Magma E n e r g y Research P r o j e c t h a s been
i n v e s t i g a t i n g m e t h o d s of e x t r a c t i n g t h e r m a l e n e r g y d i r e c t l y
f r o m s h a l l o w magma s y s t e m s w i t h i n t h e c r u s t . Heat t r a n s f e r t o
a c l o s e d h e a t e x c h a n g e r i n s e r t e d i n t o a magma body h a s been
studied extensively.
This has included a n a l y t i c a l heat transf e r s t u d i e s , m a t e r i a l s s u r v i v a b i l i t y t e s t i n g , l a b o r a t o r y meas u r e m e n t s o f c o n v e c t i v e p r o p e r t i e s o f magma, a n d f i e l d m e a s u r e m e n t s i n a f l o w i n g l a v a r i v e r a n d i n a ponded l a v a l a k e . T h e s e
s t u d i e s h a v e l e d t o t h e c o n c l u s i o n t h a t closed h e a t e x c h a n g e r s
c a n be p l a c e d i n a f l u i d magma body a n d t h a t u s e f u l a m o u n t s o f
e n e r g y c a n b e e x t r a c t e d f o r l o n g p e r i o d s of time. E n e r g y
e x t r a c t i o n r a t e s a r e c o m p a r a b l e t o c o n v e n t i o n a l h o t water or
steam g e o t h e r m a l s y s t e m s .
GASEOUS FUEL GENERATION BY MAGMA-THERMAL CONVERSION O F BIOMASS,
SAND82-0301J, J o u r n a l of E n e r g y , i n p r e s s , T. M. G e r l a c h , H. C .
Hardee, S a n d i a N a t i o n a l L a b o r a t o r i e s .
of u p p e r c r u s t a l magma b o d i e s p r o v i d e s u i t a b l e
t h e r m a l e n e r g y s o u r c e s f o r c o n v e r s i o n of water b i o m a s s m i x t u r e s
t o h i g h e r q u a l i t y g a s e o u s f u e l s . The c o m p o s i t i o n s , c o n c e n t r a t i o n s , a n d e n e r g y c o n t e n t s of t h e g e n e r a t e d f u e l g a s e s a r e
r e l a t i v e l y i n s e n s i t i v e t o t h e t y p e of magma body, b u t t h e r a t e s
a t w h i c h f u e l s c a n be g e n e r a t e d i s s t r o n g l y d e p e n d e n t o n magma
type. Fuel g e n e r a t i o n r a t e s f o r b a s a l t i c magmas a r e a t l e a s t
2-3 times g r e a t e r t h a n t h o s e f o r a n d e s i t i c magmas a n d 5-6 times
t h o s e f o r r h y o l i t i c magmas. CH4 i s t h e main g a s t h a t c a n be
g e n e r a t e d i n i m p o r t a n t q u a n t i t i e s from magma t h e r m a l e n e r g y
u n d e r most c i r c u m s t a n c e s . CO i s n e v e r i m p o r t a n t , and s i g n i f i c a n t H2 g e n e r a t i o n i s r e s t r i c t e d t o s h a l l o w b a s a l t i c magmas.
A wide r a n g e
194
TWO-DIMENSTIONAL TEMPERATURE DISTRIBUTION SURROUNDING AN
INJECTION WELL, J. C. Dunn, Sandia National Laboratories,
Proceedings of A I M 16th Thermophysics Conference, June 23-25,
1981, Palo Alto, California.
A two-dimensional analytical solution is obtained for the
steady-state temperature distribction in a porous medium during
injection of an incompressible fluid. Energy transfer by radial
convection and by both radial and axial conduction are included.
Temperatures in the porous medium can be expressed in terms of
geometry and a non-dimensional Peclet number that includes the
injection flow rate and properties of the formation and injected
fluid. The solution can be applied to the injection of spent
brine in geopressured or geothermal systems where t.emperature
distribution near the injection well is needed in order to
predict dissolution of suspended solids. Radial arid axial
temperature distributions.are presented as a function of the
Peclet number.
ENERGY EXTRACTION FROM MAGMA, J. C. Dunn, Sandia National
Laboratories, Proceedings of 1981 IAVCEI Symposium on Arc
Volcanism, Tokyo, Japan, August 28-September 9, 1981.
The objective of the DOE-funded Sandia Magma Energy Research
Project is to investigate the scientific feasibility of extracting energy from shallow magma systems within the crust. Large
amounts of thermal energy must exist in igneous-related systems
in the upper 10 km of the crust. In the western United States
J ( l o 5 quads)
alone, Smith and Shaw (1979) estimate that
of thermal energy is contained in evaluated young igneous-related
systems within the 10 km depth. A crucial aspect of our investigation is determination of energy extraction rates that can be
realized from a drillhole, for the energy extraction rates will
probably determine the incentive for development of this major
energy resource.
SUPERCONVECTING ZONES ABOVE SHALLOW HEAT SOURCES IN THE EARTH,
J. C. Dunn, Sandia National Laboratories, Proceedings of 1981
IAVCEI Symposium on Arc Volcanism, pp. 80-81, Tokyo, Japan,
August 28-September 9 , 1981.
i)wo fluid phases \liquid and gas) can coexist in a porous
medium only when the pore pressure is less than the fluid
critical pressure. In the crust, when depth exceeds that
corresponding to the critical pressure, a pure fluid can exist
either as a liquid or as a gas, dependent on fluid temperature,
and changes from one state to the other occur continuously
without phase separation. However, significantly enhanced
195
E.
Field Experiments
FY-79 LAVA LAKE DRILLING PROGRAM: RESULTS OF DRILLING EXPERIMENTS,
SAND79-1360, R. R. Neel, R. P. Striker, R. M. Curlee, Sandia National
Laboratories, December 1979.
drilling program was conducted in December 1978 and January and
February 1979 to continue the characterization of the solid and liquid
rock components of the Kilauea Iki lava lake. Six holes were drilled
from the surface and two previously drilled holes were reentered and
deepened for the purposes of measuring downhole temperature profiles,
recovering samples of solid, plastic, and molten rock, measuring
crust permeability, and determining the performance of conventional and
special drilling techniques. Conventional HQ-size (3.78 inches
diameter) core drilling equipment using water for cooling and cuttings
removal was used to successfully drill during initial entry into
1052OC formations. Conventional drilling in reentering flow-back rock
was less reliable. The specially designed water jet-augmented drag bit
or water jet-augmented core bit was needed to drill reliably into the
plastic flow-back rock and through liquid rock veins. This document
contains the drill performance data which were recorded during drilling
in the crust and the plastic and molten rock zones using both conventional and special drilling procedures and equipment.
A
FY-79 LAVA LAKE DRILLING PROGRAM -- GEOSCIENCE STUDIES: PLANS AND
RESULTS, SAND79-1361, John L. Colp, Sandia National Laboratories,
October 1979.
Fifteen experimental studies were planned for the geoscience studies
portion of the FY-79 lava lake drilling program at Kilauea Iki lava
lake, Hawaii, grouped under headings of petrologic, thermal, strength,
liquid/permeability, electrical, and other. This report gives a
location, purpose, description and feasibility analysis for each experiment. A results section for each experiment includes data gathered and
analysis to date, where available.
KILAUEA IKI LAVA LAKE EXPERIMENT PLANS, SAND80-1653, J. C. Dunn and
R. G . Hills, Sandia National Laboratories, January 1981.
Twelve experimental studies are proposed to complete Sandia's field
laboratory work at Kilauea Iki lava lake. Of these twelve experiments,
eleven do not require the presence of melt. Some studies are designed
to use proven techniques.in order to expand our existing knowledge,
while others are designed to test new concepts. Experiments are
grouped into three main categories: geophysics, energy extraction, and
drilling technology. Each experiment is described in terms of its
location, purpose, background, configuration, operation, and
feasibility
.
L
196
THE COOLING OF KILAUEA IKI LAVA LAKE, Richard G. Hills, Sandia
National Laboratories, SAND81-0114.
In 1959 Kilauea Iki erupted leaving a 110 to 120 m lake of
molten lava in its crater. The resulting lava lake has provided an unique opportunity to study the cooling dynamics of
a molten body and its associated hydrothermal system. Field
measurements taken at Kilauea Iki indicate that the hydrothermal system above the cooling magma body goes through
several stages, some of which are well modeled analytically.
Field measurements also indicate that during most of the
solidification period of the lake, cooling from above is
controlled by two-phase convection while conduction dominates
the cooling of the lake from below. In this report, a summary
of the field work related to the study of the cool.ing dynamics
of Kilauea Iki is presented. Quantitative and qualitative
cooling models for the lake are discussed.
THERMAL PROPERTY MEASUREMENTS IN A FRESH PUMICE FLOW AT
ST. HELENS, H. C. Hardee, Sandia National Laboratories,
Geophysical Research Letters (1981), Vol. 8, No. 3 , pp 210-212.
thermal penetrator that was air dropped into a freshly
emplaced pumice flow at Mt. St. Helens yielded information on
the in situ thermal properties of the pumice. The in situ
conductivity-density-specific heat product at a depth of 60 cm
was found to be 7.24 x 1
0
'
ca12/cm4s-oC2at an average pumice
temperature of 200OC. Using this data, values for the average
cal/cm-s-'C) and
in situ thermal conductivity (2.9 x
0
'
cm2/s) were estimated. These
thermal diffusivity (1.2 x 1
thermal properties are of use in studies of pumice cooling and
in the interpretation of infrared remote sensing data.
A
PROBING THE MELT ZONE IN KILAUEA IKI LAVA LAKE, H. C. Hardee,
J. C. Dunn, R. G. Hills, Sandia National Laboratories, R. W.
Ward, University of Texas at Dallas, Geophysical Research
Letters (1981), Vol. 8 , No. 12, pp 1211-1214.
New drilling techniques were recently used to drill and core
the melt zone of Kilauea Iki lava lake. Unique seismic transmission measurements were made through the melt zone yielding
the first in situ seismic velocity data through a petrologically and thermally characterized melt zone. Periodic seismic
sources were used to effectively penetrate the highly fractured
hydrothermal zone of the lava lake crust. Thermal convection
experiments in the melt zone resulted in the first controlled
in situ measurements of the interaction of water with a
basaltic melt zone. Transient energy rates of 900 kW and
197
F.
Miscellaneous
VISCOUS DISSIPATION EFFECTS IN MAGMA CONDUITS, H. C. Hardee, D. W.
Larson, Sandia National Laboratories, Journal of Volcanology and
Geological Research, Vol. 2, No. 3 , pp 299-308 (1977).
Fujii and Yueda (1974) postulated that viscous dissipation may lead to
thermal instability and explosive eruptions in the case of volcanic
conduits or dikes. Although their conclusions were based on a viscosity
function which was valid over a very narrow temperature range, calculations presented here lead to the same result for critical dike width.
A simple forced intrusion model, without viscous dissipation effects,
is also developed and found to be sufficient to explain the observed
width of volcanic conduits and dikes. The mechanism of thermal
runaway may present problems for magma energy extraction.
REPORT OF THE WORKSHOP ON MAGMA/HYDROTHERMAZI DRILLING AND INSTRUMENTATION,
SAND78-1365CI S. G . Varnado and J. L. Colp, Sandia National Laboratories,
July 1978.
This report summarizes the discussions, conclusions, and recommendations
of the Magma/Hydrothermal Drilling and Instrumentation Workshop which
was held in Albuquerque, New Mexico, May 31-June 2, 1978.' The purpose
of the workshop was to define potential drilling environments and to
assess the present state-of-the-art in drilling and instrumentation
technology for a drill hole that would penetrate through deep hydrothermal systems and into a magma.body. This effort is envisioned as a
portion of a larger program of continental drilling for scientific
purposes which has been proposed by the U. S . Geodynamics Committee of
the National Academy of Sciences. For the purposes of the workshop,
three working groups were orgahized as follows: Drilling Location and
Environment, Drilling and Completion Technology, and Logging and
Instrumentation Technology.
THE CORROSION OF SOME PURE METALS IN BASALTIC LAVA AT 1150°C, SAND79-1981,
D. L. Douglass, P. J. Modreski, and J. T. Healey, Sandia National
Laboratories, Proceedings of Hawaii Symposium on Intraplate Volcanism
and Submarine Volcanism, Hilo, Hawaii, July 1979.
One method for the extraction of thermal'energy from subterranean magma
bodies involves the use of a suitable heat exchanger which would extend
into the molten rock. Materials incompatibility may be one of the major
potential problems. The objectives of this study were to determine
basic compatibilities, to measure corrosion rates, and to determine the
mechanism of the reaction and degradation. A number of pure metals have
been exposed to molten Kilauea-1971, tholeiitic basalt at 1L5OoC for
24 to 9 6 hours. A cover gas was used to simulate the gas in solution
and an oxygen
in magma bodies, having a sulfur fugacity of 7.10 x
fugacity of 9 . 8 x 10"
PRELIMINARY ANALYSIS OF TWO ASPECTS OF MAGMA POWERED ELECTRIC GENERATION
PLANTS, SAND80-1522, E. R. Hoover, Sandia National Laboratories,
September 1980.
Two aspects critical to the development of magma electric generation
plants using closed heat exchanger systems are addressed in this
198
G.
Project Reviews/Summaries
--
MAGMA AS A GEOTHERMAL RESOURCE
A SUMMARY, H. M. Stoller, J. L. Colp,
Geothermal Resources Council, Transactions, Vol. 2 , July 1.978, p. 613.
The objective of the Magma Energy Research Project underway at Sandia
Laboratories is to assess the scientific feasibility of extracting
energy directly from deeply buried circulating magma sourc:es. The
USGS has estimated that the energy contained in molten and partially
molten magma within 10 km of the surface within the U:S. at 5 x 10" quads.
Methods of energy extraction under consideration include: the insertion
of a heat exchanger into a magma source with surface conversion to
electric power; and utilizing the reducing nature of magma to produce
transportable fuels such as hydrogen and methane. Technical elements
of the Magma Energy Research Project include: Source 1ocs.tion and
definition
the development, demonstration and verification of
exploratory techniques for locating and defining molten rock sources,
Source tapping -- the assessment of the deep-rock, near-magma environment and the technology to drill into molten rock sources, Magma property
and materials compatibility -- the definition of in situ properties of
magma and the evaluation of engineering materials subjected to that
environment, Energy extraction -- the examination and development of
processes and systems capable of extracting energy from magma sources.
--
UTILIZATION OF MAGMA ENERGY, A PROJECT SUMMARY, J. L. COlF, H. MStoller, Sandia National Laboratories, A A P G Bulletin, American Association
of Petroleum Geologists, Vol. 62, No. 7 , p. 1212, 1978, also Proceedings,
Second Circum-Pacific Energy and Mineral Resources Conference, July, 1978.
The scientific feasibility of extracting energy from magma bodies is the
objective of this project. The high temperature (approximately 1 0 0 0 ° C )
and estimated large resource (approximately 10" quads) within 10 km of
the surface in the U. S . provides the incentive for this work. The
areal extent of a near-surface molten lava body has been defined with
geophysical sensing systems. Improved knowledge of the in-situ physical properties of buried molten rock is required to assess the thickness of magma bodies. Drilling into molten lava is a complex operation
and requires further technological development. Experimer,tal studies
of rock deformation at near-magma temperatures and pressures show that
boreholes can be made to stay open. Calculational analyses of magmatic
gas samples provide a satisfactory definition of the gas content of
in-situ magmas. Material compatibility experiments show t.hat ni- and
co-based alloys can survive and operate in the magma environment.
Thermal heat exchanges can survive in molten rock and allow significant
rates of heat transfer to an internal fluid.
--
MAGMA ENERGY RESEARCH PROJECT
STATUS REPORT AS OF OCTOBER 1, 1978,
SAND78-2288, J. L. Colp and R. K. Traeger, Sandia National. Laboratories,
December 1979.
The Magma Energy Research Project is investigating the scientific
feasibility of extracting energy from magma bodies. This report
summarizes work done in FY-76, 77, and 7 8 in the four tasks of the
project: 1) resource location and definition, 2 ) source tapping,
3 ) magma characterization and materials compatibility, and 4 ) energy
extraction.
199
FY-80 ANNUAL PROGRESS REPORT--MAGMA ENERGY RESEARCH PROJECT,
SAND81-0100, J. L. Colp, Editor, Sandia National Laboratories.
The objective of the Magma Energy Research Project is to determine the scientific feasibility of extracting energy from m a g m a
bodies. Project activities are divided into five individual
tasks representing all aspects of the concept.
--
Resource Location and Definition. A joint
Task I
Sandia/USGS geophysical sensing experiment was performed a t
Kilauea Iki lava lake. The seismic experiments suggested the
presence of three reflectors; continued analysis of the d a t a is
required to discern definitive depths. Electromagnetic profiling experiments did not seem to show significant differences
in the total volume of the inferred molten zone when compared
to the 1976 data. A heat transfer model of a hydrothermal, hot
dry-out zone, and melt zone of a lava lake was developed and
verified by in situ measurements.
Petrologic analysis of Kilauea Iki cores from the 1979 d r i l l
holes was continued. Some results were: 1) the melt lens contained a maximum of 35% silicate liquid, 7 m of i t had greater
than 25% liquid; 2) the liquid trends continuously from basaltic to rhyolitic, this was inferred to be a product of in situ
crystallization.
--
Source Tapping. Triaxial mechanical testing of
Task I1
water saturated granodiorite, basalt, and andesite to 1000°C
and 3 k b was completed. A water weakening effect was noticed
only in andesite only at temperatures over 850OC. Brittle
failure occurred in dry and saturated systems suggesting t h a t
boreholes will be stable at 5010 k m depth.
--
Magma Chracterization. The characterization of
Task I11
volcanic-magmatic gases for basaltic and alkaline lavas was
completed, and a data base of C-O-H-S-C1 gas compositions
typical of mafic lavas is now available for material compatability studies. Petrographic computer codes were developed
and used to reduce microprobe analyses to classify glasses and
to calculate mineral composition of igneous rock core.
--
Task IV
Magma/Material Compatability. Preliminary results
from evaluations of 15 pure metals and 16 alloys in low press u r e , simulated magma environments suggest that: 1) the chro-.
mium content of both ferritic and austenitic stainless steels
is the most important factor in providing corrosion resistance;
2) Type 310 is by far the most corrosion-resistant alloy of any
o f the commercial stainless steels.
--
Task V
Energy Extraction. Performed heat extraction calculations for a closed heat exchanger in various hypothetical
magmas. These included the effects of high Prandtl
200
e r u p t i o n s i t e s . C a l c u l a t i o n s a n d e x p e r i m e n t s show t h a t w h e n a
c l o s e d h e a t e x c h a n g e r i s p l a c e d i n c o n t a c t w i t h m o l t e n magma,
n a t u r a l convection i s induced a d j a c e n t t o t h e h e a t exchanger
s u r f a c e . T h i s c o n v e c t i o n process l e a d s t o s t e a d y h e a t e x t r a c t i o n r a t e s o f 1 0 - 5 0 kW/m2 w h i c h a r e c o m p a r a b l e t o ' c o n v e n F i e l d tests of a d v a n c e d
t i o n a l geothermal production rates.
o p e n h e a t e x c h a n g e r s y s t e m s , w h e r e w a t e r a n d steam mix d i r e c t l y
w i t h magma, h a v e p r o d u c e d h e a t e x t r a c t i o n r a t e s a n o r d e r o f
m a g n i t u d e g r e a t e r t h a n t h o s e w i t h c l o s e d h e a t e x c h a n g e r s . Both
t h e m o l t e n magma a n d t h e h o t m a r g i n z o n e s s u r r o u n d i . n g magma
b o d i e s c a n be t a p p e d f o r e n e r g y . The t h e r m a l e n e r g y d e r i v e d
f r o m magma s o u r c e s can be u s e d t o produce f u e l s a s w e l l a s
electricity
.
MAGMA ENERGY RESEARCH PROJECT, H . C. H a r d e e , S a n d i a N a t i o n a l
L a b o r a t o r i e s , I n t e r n a t i o n a l Power G e n e r a t i o n , V o l . 5 , N o . 4 , pp
22-27 ( 1 9 8 2 ) .
Magma i s r e g a r d e d a s a l o n g - r a n g e e n e r g y s o u r c e , b u t o n e o f
such magnitude t h a t i t merits c a r e f u l i n v e s t i g a t i o n .
U. S .
G e o l o g i c a l S u r v e y s c i e n t i s t s estimate t h a t t h e e n e r g y c o n t e n t
o f magma b o d i e s w i t h i n 1 0 km ( s i x miles) o f t h e e a r t h ' s s u r f a c e
i n t h e c o n t i n e n t a l U.S. i s 800-8000 times t h e p r e s e n t a n n u a l
U.S. e n e r g y c o n s u m p t i o n . Major magma b o d i e s a r e i n t h e western
U.S.
R e s u l t s of f i e l d t e s t s c o n d u c t e d i n l a t e 1 9 8 1 by t h e N a t i o n a l
S a n d i a L a b o r a t o r i e s , A l b u q u e r q u e , N e w M e x i c o , combined w i t h
earlier research indicate t h a t it is s c i e n t i f i c a l l y f e a s i b l e t o
e x t r a c t t h e r m a l e n e r g y d i r e c t l y from t h e b o d i e s o f m o l t e n r o c k
(magma) b u r i e d w i t h i n 1 0 km of t h e e a r t h ' s s u r f a c e . ,
THE SEARCH FOR MAGMA, H .
C . Hardee, Sandia National Labora-
tories, Geophysics:
The L e a d i n g Edge of E x p l o r a t i o n , V o l .
No. 3 , pp 14-19 ( 1 9 8 3 ) .
2,
Magma, o r m o l t e n rock, i s t h e u l t i m a t e h e a t s o u r c e f o r g e o t h e r mal f i e l d s . I n c o n v e n t i o n a l g e o t h e r m a l a p p l i c a t i o n s t h e e n e r g y
from magma is tapped i n d i r e c t l y i n n a t u r a l g e o t h e r m a l f i e l d s
u s u a l l y a s s o c i a t e d w i t h magma b o d i e s . Many magma s o u r c e s , howe v e r , l a c k a n adequate g e o t h e r m a l f i e l d f o r e x p l o i t a t i o n .
Enormous q u a n t i t i e s o f e n e r g y a r e s t o r e d i n magma b o d i e s i n t h e
E a r t h ' s c r u s t . The p o r t i o n of t h i s e n e r g y t h a t c a n be t a p p e d
i n c o n v e n t i o n a l geothermal f i e l d s is a small f r a c t i o n o f t h e
t o t a l e n e r g y a v a i l a b l e i n c r u s t a l magma sources.
20 1
MAGMA ENERGY--A FEASIBLE ALTERNATIVE? John L. Colp, Sandia
National Laboratories, International Associates of Volcanology
and Chemistry of Earth's Interior, 1981 ARC Volcanism Symposium,.
August 28-September 9 , 1981, Tokyo, Japan.
The world's geothermal energy resources exist in a variety of
forms: dry steam, hot water, geopressured-water,hot/dry rock,
thermal gradients in the earth's crust, and magma. The
objective of the Magma Energy Research Project now under way
at Sandia National Laboratories with,U.S. Department of Energy
funding is to investigate the scientific feasibility of
extracting energy directly from deeply buried circulating magma
sources.
202