AEC-126/9

Mr. James E. Reeves

UNITED STATES

DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY

W A SH I NGTON 25 , D. C .

October 10, 1958

Assistant Manager for Test Operations Albuquerque Operations Office u. s. Atomic Energy Commission P. 0. Box 5400 Albuquerque, New Mexico

Dear Mr. Reeves:

IN REPLY REFER TO:

Transmitted herewith are ten copies of TEI -729, "The action

of heat and of superheated steam on the tuff of the Oak Spring formation,"

by George W. Morey, August 1958.

This report is part of our Nevada Test Site project. We

plan to incorporate the information in TEI-729 with that in other

reports on this project for publication by the Geological Survey.

· Sincerely yours,

-~ .~~ ~/Vc):,R

j..,- W. H. Bradley Chief Geologist

UNI1rED STAIJ::'ES DEPARTMENT OF THE INTERIOR

GE LOGI CAL SliRVEY

THE .ACTION OF HFJ\.T A~TD OF SUPERHEATED STEAM

ON ·IE~ T0~ OF TFili OAK SPRING FORMATION*

George W a Morey

Augu.st 1958

Trace El ements Investiga t i ons Report 729

This preliminary report is distributed without editoria l and. technical review f or conformity ·with official standards and nomencla ture . It is not f or public . inspection or quot ation.

*This report concerns work done on behal f of Albuquerque Operations Office, U. s. Atomi c Energy Commission ..

2

USGS - TEI - 729

Distribution No. of copies

Albuquer que Opera t:i.ons Office ( J.. :F~.. Ree·7es) o •• o " .... o .... " ... o e .. ., .. o • ., .. 10 Division of Research , Washington (D .. R . Mi.l_er) .... .... ., ., .. o. o.......... 2 Office o.f the Commissioners, Washington (J .. C .. Pot~s ) •o••ooe•o•o •o 1 Office of Opera tions Analysis & Plan~ing, Washi ngton ' P .. C. Fine) 1

Chemistry Division, ArgorLne National Lab . (W, M .. Mann.ing ) .. • .. • • • .. .. • 1 Chemical Tech ., Di v ., Oak Ridge Natl. Lab .. (F~ R. Bruce) ... . ~••o•ooo 1 Engineer Research & Deve~opment Lab"' Ft .. Belvoir, Va.

(Chief , Spec:ia l P:t'l.. .. jec-ts B"':"'82u.ch) o ooo. oott<> o G> <> o<>&<> o o•eaoseooeeooeo 1 Health Physi~s Div .. , Oak Ridge Natl . La.b o ( F .. L .. Parker) ..... ..... •• 3 Los A- amos Scientific Labor a tory ·· J. iL. Ha.ll .J .. ,. .. .. o ..... o •••••••• o .. • 1 Uni v. Ca lif. Radia tion J...a b., , L~'~-vermore (G .. W. Johnson) . .. ...... " •••• 10 U .. S. Naval Ordnance Lab" ' Whi+.e Oak, Mri . (J .. E .. .Abla!'d) . .. .......... 1 U. S. Naval Radiological Lab .. , San Francisco (IlL E . Ballou) • • • • • • • 1

U. s. Geological Survey~

Engineering Geology Bran.ch , Denve~c· ...... o ........ o & .. • • • • • • • • .. .. • • • • • • • • 10 Fuels Branch, Denver •o••• .. •••&ee &o o•• o • o •••eo•••"'"""••••.,••<>••e••• 2 Geochemistry and Petrology Br anch, Washington ••o~••••o• .. o••• •••••• 8 Geophysics Branch , Washington o•e•e ••oo .... ..... .......... ..... o ..... .......... 6 Militar y Geology Bran~h , Washington •••• oo •••o•••·~••••eooe•••••o•• 2 Mineral Deposits B:ranch, Washington ............ .,oooo••o•• •• """'"""•"• 2 Radiohydrology Section , Washington ••• o., e " ...... a." ••• e ... 0 · .. . o ...... .., e • • 6 TEreo' De nve r ••••• 0 Q • e Q ••••••• ~ 0 Qo •••• • e 0 0 Cio 0 0 0 0 G () Q •• G • 0 A} " •• 0 •• • · . 0 • • l TEPCO, Washington (including maste:r) .... o•o•••oo.,ooeoe<><>OOCOee•o••• • 4

74

Page

Abstract 4

Introduc~ti. o!J. 4

Experi.me r..-:;s in. a .i!" 5

Expe r iment s E2. s~;~~Jerheate •1 s+,eam at h:~g:C. :r;c:'e BS'-)~'e o ~, o .... o........ 9

RefeTences

Table l .

4.

e o o e o. e • (I o t'> " e t:~ t':'l o o ~ f'l fl e o o I") <» o o o a o o tJ o c· n o (} o o o o o o e 41 • & o o o e •

in a i.r

Effect u:f heat::.:o_g he-J.landi.te ., -,...., a~i.~~·

X~ray :~?atter::; of the l12:~~ :1.e~~":i:;if::_e(. :.a:ri~.-at:.~.-e of !J.eula:'J.d.:.te ·{~:r:tich ~\ra. ,s ob·:.a5.r..ed. b;y- ::.ea.t2.l!.g .b.eu:l.anL~.i te f r o:Ti Icelar2.d. to 290° C ~- D:!:" 64 !:D:.J::.'S, and :te1;~landi te ::.::.-:;. ·~uff of tb.e Oa.~~. S:p:':"'2 ~2.g f or::nat:Lc>rl to ~~6~~c C fQr 4 d.a;y-s

The e f:'ec t r::;f sv.pe:::-hea.ted . .stemr. a-+~ hig:!.". pressu.:':"e 0:::1

t :he tuff' of the Oak. Sp~<~.::1~ forma-cion. •• o ...... G., • ., ........

13

6

8

10

ll

4

TEE A"GTION OF HEAT Al\ID OF SOPERfiEATED STEAM

ON TUFF OF THE OAK SPRING FORMATION

By G-eorge W. Morey

ABSTRACT

Samples of tuff of the Oak Spring f ormation hea ted in air at different

temperatures were examined. with the petrographic microscope and by X-ray

diffraction methods. The changes in the heulandi te , which makes up the

greater part of the tuff, can be used to estimate the temperature to which

the tuff had been heatedo The tuff becomes f luid enough to begin to flow

under its own weight at about 1,200° C in air, but even a t higher temperatures

the molten w~terial has extremel y high viscosityo

Samples of the tuff were heated in superheated steam at high pressures,

and from these experiments it is concluded that recrystallization of the

heulandite with formation of plagioclase feldspar is indicative of the presence

of steam at high temperature and pressure during recrystallization ..

INTRODUCTION

The underground nuclear explosion of September l~ 1957 took place in a

rhyolitic tuff of the Oak Spring formation of Tertiary age. In the specimen

used for the experiments described below the originally glassy shards have

been completely altered, chiefly to the zeol ite mineral heul andite

[(Ca,Na2)0•Al203 ·6Si02•5H20 ] . Heulandite makes up about 70 percent of the

rock specimen. The remainder is about 20 percent quartz, many of bipyramid.crl

habit indicating that they were formed as high-quartz above 575° C, and

r:: /

10 percent of K feld.spar, plagioclase, hornblende, mag~1eti te, and bi.oti te

(Hansen and Lemke, 1958)., A considerable amount o.f -~!later is a.l.so present.

Some of this is combi ned. in the heulandi te, which i.d.eally contains

15 percent water. If the tuff is 70 per'cer.~.t he<.Llan.d.:f. 'te, i.t shm.1.ld. have a

minimum water con.tent of J,O percent .. Actual analyses of -l:uff range from

10 to 29 percent "Water, so t:~1e quantity of water i::1. the -:;uff actually subject

to the heating efi.ects of the naclear explosi.or.;. is UJ.'lce:.:'tain.

The authoY takes pleas'l.J2'e j_n. acknm-1:::..edging tl~.e assistance of

W. F. Outerbridge in the pet:.ographic examinati.ons ar.'::. of Daphne R .. Ross in

the X-ray diffraction st·o.c":.ies. T!le \<Tork. herein repcr,ted. is part of a program

being corrd.ucted ·:::r;y the U. S" C-eologi.cal Su:.:·vey 02 behalf of Al~uquerque

Operations Office, U .. S. Atomi-c Energy Com.rnissio!.' ...

EXPERIMENTS L\! AIR

Sam;ples of tuff taken. from the exploi3ic:n chani::,er prior to -th.e shot, and

identified by the number G57 -9-l, ·were purN"d.e:red, :pla eed in sma::;_l crucibles

hanging i:n an automatically con.tl"ollec1 quench1ng furnace, ar1d. heated in air.

After heating, the samples ·were :!:'emoved and exarr..iEed with the petrographic

microscope and. X-.:ray diffractometer. The ex:perime~.tal conditions and.

results of these experiments are sho•..m. in. table l Q

The author estimates, from the chemical compositicn of the material and

the melting :!:'elat i .ons of per·t:!.nent systems -~..r~i.c!h have al:!:'eady been studied

at the Geophysical Iaborato:r·y, Carnegie Irrst:i. t·u.tion of Washington , that

the temperature of completim:·"' of the melt~ .. ng p:('ocess is abou.t 900° C. This

estimate p:r-esl2pp9ses that the material -w-as O:::'iginally crystalline and that

eq_uilibril:'.m Y.TaS reached., 1r:he last crystallin-e phase to disappear wou ld be

6

Table 1.--Effect of heating tuff of the Oak Spring formation in air.

Temperature

.J£L Time Condition

36o 4 days X-ray pattern shows heulandite altered to

unidentified., Other minerals unchanged.

500 18 hrs Heulandite has decomposed to glass. Other

minerals unchanged.,

760 42 hrs Doo

1,032 42 hrs Not sintered. Heulandite has decomposed to

glass. Other minerals unchangedo

1,150 8 days Partly sintered; heulandite decomposed to bubbly

glass. Other minerals Q~changedo

1,160 4 hrs Thoroughly sintered and cemented together by

bubbly glass. Other minerals unchanged.

1,191 6 days Melted, but phenocrysts of ~uartz and K feldspar

are not altered. In addition to the bubbly

glass formed from heulandite, there is a clear

glass probably formed from the plagioclase.

1,205 5 days Melted to bubbly glass with some phenocrysts of

quartz and K feldspar remaining metastably.

7

silica i n the :form of' quartz or trid;ylili te.. The tu:rf original y , however,

-was largely gl ass, s o the me; ting process v.Jas near completion , 'but ·the phases

pre-sent , quartz .and f e l dspar , are as wou.ld be expected ~ However ~ equilibrium

in mixtures of this general composition -~ras real.hed very slo-wly, as is shown

in tabl e 1 " At 1 ~ 032° C the heul andi te had decomposed t o a gl ass , but t he

material was still so viscous that the powder did not s:.:nter together i n

42 hours" At 1 ,150° C sintering had begun, and a t 1 , 19-o C the material was

thoroughly me l ted t ogethe:c" Tr,._ro types of gl a ss could. be d.istin.gaished,

·one ·a bubb l y gl ass formed. b y decomposition of t he heul andite , and the other

a clear gl ass chiefly for med by t he melting of t he p l agioclase feldspar.

The beha·vi.or of t hese material s on heating is consistent with the known viscosity

of silica te melts. At 1,200° C an ordinary soft gl ass l ike window glass will

have a viscosity of' 10s poises; molten albite about l07 poises and molten

orthoclase ~ 10s poises ..

When tuff is heat ed a t lower temperatures ' 500° and 760° C) about the

only change is the driving off of the combined water in heulandite ,

resulting i n the formation of a bubbly gl as s , and. the condj_tion (table 1) of

the heulandite is evidently diagnostic of the temperat~es to which the tuff

had been subject edo To secure further i nformation on this, samples of a

well-crystallized heulandite from Iceland -were heated in a ir a t the

temperatures and for the time given in table 2, and t he products studied

by X-ray diffraction. At 199° C the heulandite pattern remained unaltered.

At 290° C with short exposures the x.ray pattern obtained was that of

heulandite~ but with s l ightly altered spacingso However, when heated for

8

Table 2.--Effect of heating heulandite in airo

Temperature (C)

199

290

505

Time (hrs)

17

64

1

64

1

4

113

3

20

Conditi.on

Heulandi.te remained unaltered.

Do.

X-ray pattern was essentially that of heulandite,

with slightly altered spacings.

X-ray pattern showed that the heulandite had

completely altered to an unidentified compound.

Same QUidentified pattern.

Do.

Do.

Noncrystalline, except for a trace of quartz.

Doo

9

64 hours , t he tu:ff yiel.ded a new X=ra y pa-tter n (tab l e 3 ) wh :i.ch di.d n ot match

t h ose o:f··a ny mine r a ls i~. the fTles of t he U .. S., G8olog i ca l Survey . This

un.ide nt ified ·pha s e persis-ted even after ll3 hours hea ting a t 3&J° C. This

was t he s ame pattern obta i ne d by hea t ing tufT to 360° C f or 4 days (re f e rred

t o ·-as 11Un i dentif ied 19 i n t ab le 1) o

The a l t era t i on o f t he heu.landi t e evidently prov i.des a clue t o the

tempera t u r e a t wh i ch the tuf f ~ras heated a s the !"esu:t of the heat give n off

by t he (e~<rplos ion and i t is pla:~med. t o ma ke X- r a y dif :fra cti on s t u di es of

samp les obt aine d_ in t he survey of t he r e gion of the coll apsed. det onat ion

ca v i ty .

EXPERI.MEN'I'S IN' SUPEFJIEATED STE...AM AT HI GH PRESSURE

I na smuch a s a l a r ge amou_n.t of steam ~ras f orme d a s a resul t of t he

expl os ion (J ohns on and o t he :r·s , 1958) a!J. a t t emp t wa s made t o fi n d the effect

of superheat ed. ste a m o~ tuf f a t h i.gh pTes sureso ~ne appa r a tus used was t hat

de s cr i.be d by Morey a nd He s s e .lges ser (1952 ) , i n which a close d pressure vessel

of Inco~el X wa s hea ted i~ a. i'u:::-na ce ·~~rith automatic t emperature contr o lJO

About a hal f-gr am s a mpl e of the powdered tuff, identified. by the number

G57-9-1, wa s p l a ced in a p l at i num crucib le wi t h a l itt l e water , put into

the bomb, a n d hea ted t o the des i r ed temp e r a t ure . The pump was t hen started,

and water pumped i nto t he hot bomb with an a utomatica lly controlled pump

unti l the des ired :... Y"esm.rre wa s r eached .. The results a re shown in table 4.

The lowest tempera ture chosen ·wa s 500° C a In 3 hours a t 5,000 psi,

the heula ndit e had become a l most e ntire l y non cr ysta lli ne, j ust a s i n t he

runs in a i r , but a ne·w u-r.Lid.entJ. f i ed pattern ha d begun to develop whi ch had

some of the str ong l ines of the plagi.oc l a se f e ldspars o I n 96 hours a t

10

TabLe 3.--X..;.ray pattern of the unident.i:fied derivative of heul andi te which ··was · obtained by heating heuland~ite from I celand. to 290° C f or 64 hours , and heulandite in tuff of the Oak opring for mation to 360° G f"br 4- days .. ~/

X-ray powder data for uni dentified f ilm noa 11779, CQKa radiation, l = 1.5418 A, Ni fi lte r , cutoff = 11 A, camera diameter = 114e59 mm

d A) I -8.3 100 7 .. 6 25 6e7 35 5.6 25 5 .. 2 35 4.96 35 4.27 9 4.13 9 3.90 6 3 .80 35 3.65 50 3o52 9 3. 36 71 3.27 13 3.13 6 2.93 3 2o9l 3 2.82 18 2.76 4 2.69 6 2.56 6 2.24 3 2.19 2

"};/ Analyst, Daphne R .. Ross, U. S. Geol ogical Survey ..

11

Table 4.--The eff'ect of super heated s team at high pr essure on the

Temperature (c)

500

500

6oo

tuff of the Oak Spring for matione

Pressure (psi)

5,000

6,500

15,000

15,000 30,000

Time (hrs) Condit i on

3 Heulandite h~s become almost entirely

17

18 2

noncrystal line with some plagioclase

feldspar vresent i n it. Phenocrysts

not appreciably a l tereda

Heulandite has recrystallized to plagioclase

feldspar. Phenocr ysts not appreciably

altered.

Heulandite recrystal lized to plagioclase.

Phenocrysts not appreciabl y altered.

Heulandite has recrys t all ized to a

plagioclase fe l dspar , probably oligoclase.

Phenocrysts not appreciably altered.

12

6,500 psi the heulandite had changed almost completely to plagioclase, but

the crystals were still too f i ne grained for the plagioclase to be identified.

At 600° C and 15;000 psi the plagioclase lines were better developed. Finally,

a run was made at 650° C and 15,000 psi for 18 hour s , then the pressure was

increased to 30,000 psi for two hours. In this run the feldspar was tentatively

identified as an oligoclase , a plagioclase in the albite -anorthite series

containing from 10 to 30 percent anorthite. It i s probable that this is the

feldspar formed in all of the runs at lower temperature and pressure. It is

noteworthy that a glass of the composition of oligoclase will not crystallize

eYen in many months when heated dry at 500° Ce In all of the above runs the

phenocrysts of quartz, K fe l dspar, and plagioclase apparently remained

unaltere d.

A sample of the Iceland heulandite heated for 3 hours at 500° C and

15 ,000 psi steam pressure contained some noncrystal l ine material, plagioclase ,

and some quartz.

It is evi dent that the change of heulandite to feldspar is indicative

of an exposure to superheated steam, and any study of the tuff collected

from the collapsed explosion chamber should include an X-ray diffraction

study of the mater ial with special attention to the change s in the

heulandite . Any change to plagioclase would be indicative of exposure t o

superheated steam.

13

REFERENCES

Hansen, W. Ro, and Lemke, R. W., 1958, Geology of the USGS and Rainier trmnel areas, Nevada Test Site: U. S. Geol. Silrvey TET-716 (unpublished).

Johnson, Gerald W. 1 Pelsor, Gene To, Preston , Roger G., and Violet, Charles E., 1958, The underground nuclear detonation of September 19, 1957, Rainier: University of C~lifornia Radiation Labo UCRL-5124 , 27 p.

Morey, George W., and Hesselgesser, James M., 1952, The system H20-Na20-Si02 at 4oo° C, Bowen Volume, Part 2: Am. Jouro Sci., p. 343-371.