8/12/2019 Noble and Vidal-1990
1/6
EconomicGeologyVol. 85, 1990, pp. 1645-1650
SCIENTIFIC COMMUNICATIONS
ASSOCIATION OF SILVER WITH MERCURY, ARSENIC, ANTIMONY, AND
CARBONACEOUSMATERIAL AT THE HUANCAVELICA DISTRICT, PERUDONALD C.
NOBLE
Mackay Schoolof Mines, Universityof Nevada-Reno,Reno,Nevada
89557AND CSAR E. VIDAL
PerubarS. A., Juande Arona 830, San sidro, Lima 18,
PeruIntroductionand GeologicSetting
The Huancavelica istrict n centralPeru (Fig. 1)is the largest
producer of mercury in the westernhemisphere nd one of the more
mportantmercurydistricts n the world. The geologyand ore depositsof
the district have been describedby Yates et al.(1951),
Fernandez-Concha t al. (1952), and McKeeet al. (1986), who
togetherprovidea comprehensivebibliography.Mostof the ore, ncluding
hat of the SantaBrbaramine, the most mportant n the district (Fig.
1), ishostedby steeply dipping quartz sandstone f theEarly
CretaceousGran Faral16nMember of the Goyl-larisquizgaFormation.A
number of smallerdepositsin the districtare hostedby limestoneof
the Pucarand MachayFormations f Jurassic ndEarly Creta-ceousages,
espectively; he replacementdeposits fthe Botija Puncomine are the
best exampleof thisore type. Minor fracture illings n late
Miocenedacitelavasand volcaniclastic andstone f early Mioceneage
(McKee and Noble, 1982; McKee et al., 1986)are alsopresent;sucha
cinnabarvein is exposed nthe Espafiolamine.The lavaspresumably re
volcanicequivalents f high-level ntrusivebodies hat drovethe
several hydrothermal systems rom which themercuryand
associatedmetalsof the deposits f thedistrictwere deposited McKeeet
al., 1986).The minesof the Huancavelica istrict,and par-ticularly
he SantaBrbaramine, were worked nten-sivelyfor hundredsof years,
ypicallyby very lowcost abor.For this reason ndbecausen
manycasesthe distribution of mercury is irregular, in
manyformerworkings t is difficult o find
megascopicallyvisiblecinnabarn outcrop. ntensehandminingdur-ing
Spanish olonial imesexplains oth the generallylow Hg valuesobtained
on samplingof the Chacla-tacanaopen pit and the lack of success f
recent at-temptsof bulk mining.
Mineral AssociationsAs described y Yateset al. (1951)
andFernandez-Conchaet al. (1952), cinnabarand esseramountsof
native mercury are closely associatedwith pyrite,realgar,
orpiment, arsenopyrite, nd stibniteand, lo-cally, with
hydrocarbonand/or bituminousmaterialclearly transportedby
hydrothermalsolutions. hismineral assemblage ccursmainly as
impregnationsin the quartzite of the Gran Faral16nMember.In
addition o the mercury occurrences, olyme-tallic veins and bodiesof
hydrothermalbrecciaareknown n the Huancavelica istrict (Fig. 1),
and anumberof narrowPb-Zn-Agveinsare present n
sur-roundingareas.Pyrite and tetrahedriteare the mostimportant
minerals n the veinsat Ccollccemina,Far-al16n,and Yanamina Fig. 1;
see also McKee et al.,1986). Galena,sphalerite,
rsenopyrite,halcopyrite,jamesonitc, tibnite,quartz,barite,
andhydrocarbonand/or bituminousmaterialare associated ith
theseminerals.Semiquantitative ptical emission
pectro-graphicanalysis asshown he presenceof 10 to 100ppm Hg in
severalspecimensrom theseveins;Bi andSn were detected at the same
level of concentrationin a sample rom Yanamina.Wall-rock
materialcon-sists f argillicallyaltered dacite ava of late
Mioceneage at Ccollccemina; t Yanamina he veinsare hostedby
sandstone.Bodiesof hydrothermal recciawere recognizedby Yateset al.
(1951) and Fernandez-Concha t al.(1952). The bodiesat
Cabramachay,Modelohuayco,and Nifiabamba Chircoromojo)Fig. 1) have
beenstudied n more detail by Vidal and Cabos 1984).The breccia
bodies at Cabramachay nd Modelo-huaycoare polymictic,with variably
ounded rag-ments f Cenozoic olcanic ndMesozoic edimentaryrock
ndicating ertical ransport.Wall-rockcontactsare irregular and
gradational,with fractured but in-terlockingblocksof limestone r
volcanic ock grad-ing inward to polymictic breccia. The matrix is
com-posedof comminuted ock fragments ementedbyquartz, chalcedonic
ilica,and clay. Tracesof barite,marcasite,galena, and
sphaleritewere observed nplaces,and large bodiesof
iron-manganeseossanwith associated zones of carbonaceous material
arepresent n the Cabramachay recciabody. Between
1645
8/12/2019 Noble and Vidal-1990
5/6
SCIENTIFIC COMMUNICATIONS 1649
erencescited therein) indicating hat mostsedimen-tary
rock-hosted reciousmetal deposits re formedat depthsof a kilometer
or more.An importantdifferencebetween he Huancavelicadistrict'and
the depositsdiscussed bove s the oc-currenceof silver with mercury
nsteadof the asso-ciationof goldwith mercuryor
mercurywithoutpre-ciousmetals.This appears o be in part
empiricallyexplainablen termsof geologic etting nd he natureof
spatially nd emporally ssociated,ndpresumablygenetically elated,
gneous ocks,but wouldalsoap-pear o require avorable onditions f
metal ransportand deposition.Althoughsomenotablegolddiscoveries
avebeenmadeduring he pastdecade, t hasbeen recognizedfor a long
time that silverpredominates ver gold nthe myriad polymetallicand
preciousmetal depositsof the highlands f Peru (e.g.,
Petersen,1965). Oneexample, as pointed out by Noble and
Silberman(1984), is providedby the enargite-and etrahedrite-bearing
veinsof Julcani,Cerro de Pasco,and othersimilardeposits, hichare
the silveranalogues f en-argite-gold- or acid-sulfate-type
epositssuch asGoldfield, Nevada, and Summitville, Colorado.
Minoroccurrencesf mercury,moreover, re found n var-iousof the
polymetallicdistrictsof central Peru, forexample, at the
HuachocolpaPb-Zn-Ag district 25km south of Huancavelica, where
mineralization tookplace at nearly the same time as at
Huancavelica(McKee et al., 1975; Birnie andPetersen,1977; Bruhaet
al., 1982).As with the manysilver-dominantolymetallic e-positsof
central Peru, the presenceof silver in theChaclatacana pen pit
appears o reflect its spatial,temporal, and probably genetic
associationwith amajorpulseof strongly alc-alkalic
ubduction-relatedvolcanicand plutonicactivityof middle o late
Mio-cene age (Noble and Bowman, 1976; McKee et al.,1986; McKee and
Noble, 1989; Noble et al., 1989).The McLaughlin,McDermitt,
andAlmadendeposits,in contrast, re closely ssociated ith basaltor
basalt-derived ntermediate ockserupted n extensional rtransform
ectonic settings McLaughlin and Don-nelly-Nolan,1981; Noble et al.,
1988; Rytubaet al.,1989). Basaltic, rather than intermediate to
siliciccalc-alkalic,magmas ppear o havebeen the sourceof the
mercury,andpreciousmetals,wheredeposited(e.g.,McLaughlin),
adrelatively ow, albeitvariable,Ag/Au ratios.Nevertheless,he Ag/Au
ratiosof the Chaclatacanaores appear oo high to explainsimplyby
geologicsetting.Low base metal
adularia-sericite-typepi-thermalandhot springs ystemsuch sBorealis,
ondGold Bullfrog,Bodie, Delamar, Oatman,and RoundMountain have
relatively low Ag/Au (Heald et al.,1977) ratiosandsome, or
example,McLaughlinandthe Gooseberry ystemn westernNevada
Sprecher,
1985), zonestrongly pward o very owAg/Au atios.In contrast,
dularia-sericite-typepithermal ystemscontainingignificantmounts f
basemetalsypicallyhavemuchhigherAg/Auratiosandmayzoneupwardandoutward
o higherAg/Au ratios e.g., ClarkeandTitley, 1988). The
mercurydeposits f the Huancav-elicadistrictmaybe anextreme istal
xample f thiscommonhigh basemetal zoningpattern. More
com-plexpreciousmetalzoningpatterns,n
partprobablyreflectinghost-rock hemistry,have been observed(e.g.,
Alvarezand Noble, 1988).Such dif[rences in relative metal abundance
andzoning equireselectiveransportationnddepositionof
silverandgold.The very owAg/Auratiosof certainCarlin-type
edimentaryock-hostedolddeposits asbeen explainedby Hofstraet al.
(1990) by transportin relatively HS--rich and chlorite-poor
solutions,with gold precipitationbeing caused n part by re-moval of
reduced sulfur from solutionby sulfidationof iron present n the
host ock. Possiblyhe high Ag/Au ratiosof the Chaclatacanapecimensn
part reflecthigh ratiosof C1- to noncomplexededucedsulfur nthe
distal,mercury-rich ydrothermal olutions.
AcknowledgmentsWe thank Buenaventurangenieros,S. A. and
So-ciedad Minera E1 Brocal for permission o publish,GaryFetchko or
adviceon analytical rocedures ndcomments on the resultant data,
Ulrich Petersen forhelpful commentson the manuscript,and
AlbertoBenavidesQ. for hiswholehearted upportof our
on-goingstudiesof mineral deposits n Peru.
REFERENCESAlvarez A., A., and Noble, D.C., 1988, Sedimentary
ock-hosteddisseminatedprecious metal mineralization at Purisima
Con-cepci0n,Yauricochadistrict, central Peru: ECON.GEOL.,v. 83,p.
1368-1378.Bagby,W. C., and Berger, B. R., 1985,
Geologiccharacteristicsof sediment-hosted,isseminatedrecious-metal
epositsn thewestern United States:Rev. Econ. Geology, v. 2, p.
169-202.Bagby,W. C., and Cline, J. S., 1990, Constraintson the
pressureof formationof the Getcheil gold deposit,Humboldt
County,Nevada, as interpreted from secondary-fluid-inclusion
atalabs.l:Geol. Soc.Nevada-U.S. Geol. Survey,Geologyand
OreDepositsof the Great BasinSymposium,Reno-Sparks,Nevada,1990,
Program with Abstracts,p. 70.Birak,D. J., andHawkins,R. B., 1985,
The geology f the Enfield
Bell mineand he JerrittCanyon istrict,ElkoCounty,Nevada:U.S.
Geol. SurveyBull. 1646, p. 95-105.Birnie,R. W., andPetersen,U.,
1977, The paragenetic ssociationand compositionaloningof lead
sulfosalts t Huachocolpa,Peru: ECON. GEOL., v. 72, p.
983-992.Bruha,D. J., McKee,E. H., andNoble,D.C., 1982,
Paragenetic,fluid-inclusion nd geochronologicaltudyof the
Teresitaveinsystem,Huachocolpadistrict, Peru labs.l:Geol.
Soc.AmericaAbstractswith Programs, . 14, p. 152-153.Clarke, M., and
Titley, S. R., 1988, Hydrothermalevolution nthe formationof
silver-gold eins n the Tayolita mine,
SanDi-masdistrict,Mexico:ECON.GEOL.,v. 83, p. 1830-1840.Cox,D. P.,
andSinger,D. A., 1990, Descriptive ndgrade-tonnagemodels or distal
disseminated g-Au deposits:A supplement
8/12/2019 Noble and Vidal-1990
6/6
1650 SCIENTIFIC COMMUNICATIONSto U.S. Geological Survey Bulletin
1693: U.S. Geol. SurveyOpen-File Rept. 90-282, 8
p.Fernandez-Concha,J., Yates, R. G., and Kent, D. F., 1952,
Geo-logladel distritomercurffero e Huancavelica, er6:Peru, nst.Nac.
Inv. Fomento Mineros Bol. 5, 56 p.Fisk, E. L., 1968, Cordero mine,
Opalite miningdistrict, n Ridge,J. D., ed., Ore depositsof the
United States, 1933-1967 (Gra-ton-Sales ol.): New York, Am. Inst.
Mining Metall. PetroleumEngineers, p. 1573-1591.Havenstrite, S. R.,
1983, Geology and ore depositsof the Taylorminingdistrict,White
Pine County, Nevada:NevadaBur. MinesGeology Rept. 36, p.
14-26.Heald, P., Foley, N. K., and Hayba, D. O., 1977,
Comparativeanatomy of volcanic-hosted pithermal
deposits:Acid-sulfateand adularia-sericite ypes:ECON. GEOL.,v. 82,
p. 1-26.Hetherington,M. J., and Cheney,E. S., 1985, Origin of the
opalitebrecciaat the McDermitt mercurymine, Nevada:ECON.GEOL.,v.
80, p. 1981-1987.Hofstra, A. H., Landis, G. P., Leventhal, J. S.,
Northrop, H. R.,Rye, R. O., Doe, T. C., and Dahl, A. R., 1990,
Genesisof sed-iment-hosteddisseminated old depositsby fluid mixing
andsulfidationof iron in the host rocks: Chemical reaction
pathmodeling f ore depositional rocessest
JerrittCanyon,Nevadalabs.: Geol. Soc.Nevada-U.S. Geol.
Survey,Geologyand OreDepositsof the Great
BasinSymposium,Reno-Sparks,Nevada,1990, Programwith Abstracts,p.
55.Lehrman, N.J., 1986, The McLaughlin mine, Napa and
YoloCounties,California: Nevada Bur. Mines GeologyRept. 41,
p.85-89.
-- 1988, Geologyand geochemistry f the McLaughlinHot-Spring
precious-metaldeposit, California Coast Ranges abs.,in Schafer, R.
W., Cooper, J. J., and Vikre, P. G., eds.,
Bulkmineablepreciousmetal depositsof the western United
States.Symposiumproceedings:Reno, Nevada, Geol. Soc. Nevada,
p.732.McCormack, J. K., 1986, Paragenesis nd origin of
sediment-hosted mercury ore at the McDermitt mine, McDermitt,
Ne-vada:Unpub. M.S. thesis,Univ. Nevada-Reno, 7 p.McKee, E. H., and
Noble, D.C., 1982, Miocene volcanism anddeformation n the Western
Cordillera and high plateausofsouth-centralPeru: Geol. Soc. America
Bull., v. 93, p. 657-662.-- 1989, Tectonic
events,magmaticpulses,and base-and pre-cious-metal mineralization
in the central Andes, in Ericksen,G. E., CarlasPinochet,M. T., and
Reinemund,J. A., eds., Geol-ogy of the Andes and its relation to
hydrocarbonand mineralresources:Houston, Texas, Circum-Pacific
Council EnergyMineral ResourcesEarth Sci. Ser., v. 11, p.
189-194.McKee, E. H., Noble, D.C., Petersen, U., Arenas F., M.,
andBenavidesQ., A., 1975, Geochronologyof late Tertiary
vol-canismand mineralization,Huachocolpadistrict, central
Peru:ECON. GEOL., v. 70, p. 388-390.McKee, E. H., Noble, D.C.,
andVidal C., 1986, Timing of volcanicand
hydrothermalactivity,Huancavelicamercurydistrict,Peru:ECON. GEOL.,
v. 81, p. 489-492.McLaughlin, R. J., and Donnelly-Nolan, J. M.,
1981, Research nthe Geysers-ClearLake geothermalarea, northern
California:U.S. Geol. Survey Prof. Paper 1141,259 p.Mining
Magazine, 1982, The McDermitt mine--the U.S.A.'slargest producer of
mercury: v. 4, p. 261.Noble, D.C., 1984, Resultsof
cyanide-extractionestsof samplesfrom the Huancavelica district,
Peru: Lima, Peru, BuenaventuraIngenieros, S. A., private rept., 6
p.Noble, D.C., and Bowman, H. R., 1976, Geochemical and
fieldconstraints n the depth of differentiation nd eruptive
historyof siliciccalc-alkalicmagmas elated o
baseandpreciousmetalmineralization,Andesof centralPeru labs.: Geol.
Soc.AmericaAbstractswith Programs,v. 8, p. 615.Noble, D.C., and
Silberman,M. L., 1984, Evolucibnvolcfnicahidrotermaly cronologla e
K/Ar del distritominero de Julcani:Soc.Geol. Per6, Vol. Jubilar 60
Anniv., pt. 5, 35 p.
Noble, D.C., McCormack, J. K., McKee, E. H., Silberman,M. L.,
and Wallace, A. B., 1988, Time of mineralization in theevolution of
the McDermitt caldera complex, Nevada-Oregon,and the relation of
middle Miocene mineralization in the north-ern Great Basin o coeval
regional basalticmagmaticactivity:ECON. GEOL., v. 83, p.
859-863.Noble, D.C., Eyzaguirre,V. R., andMcKee, E. H., 1989,
Precious-metal mineralization in the Andes of Per6, in Ericksen, G.
E.,CariasPinochet, M. T., and Reinemund,J. A., eds., Geologyofthe
Andesand ts elation o hydrocarbon ndmineral esources:Houston,
Texas, Circum-Pacific Council Energy Mineral Re-sourcesEarth Sci.
Ser., v. 11, p. 207-212.Nutt, C. I., Thorman, C. H., Zimbelman, D.
R., and Gloyn, R. W.,1990, Geologicsettingand
reconnaissancerace-elementgeo-chemistryof the Detroit mining
district and Drum gold mine,Drum Mountains,west-centralUtah labs.:
Geol. Soc. Nevada-U.S. Geol. Survey, Geology and Ore Depositsof the
GreatBasinSymposium, eno-Sparks, evada,1990, Programs
ithAbstracts,p. 63-64.Petersen,Ulrich, 1965, Regionalgeologyand
major ore depositsof central Peru: ECON. GEOL.,v. 60, p.
407-476.Percival, T. J., Bagby, W. C., and Radtke, A. S., 1988,
Physicaland chemical features of precious-metaldepositshosted
bysedimentary rocks in the western United States, n Schafer,R. W.,
Cooper, J. J., and Vikre, P. G., eds.,Bulk mineablepre-ciousmetal
depositsof the western United States.Symposiumproceedings:Reno,
Geol. Soc. Nevada, p. 11-34.Radtke, A. S., Rye, R. O., and
Dickson,F. W., 1980, Geologyandstable sotope tudies f the Carlin
golddeposit,Nevada:ECON.GEOL., v. 75, p. 641-672.Rytuba,J. J., and
Glanzman,R. K., 1979, Relationof mercury,uranium, and lithium
deposits o the McDermitt caldera com-plex, Nevada-Oregon:Nevada
Bur. Mines Geology Rept. 33,p. 109-117.Rytuba,J. J., and McKee, E.
H., 1984, Peralkalineash-flow uffsand calderasof the McDermitt
volcanic ield, southeastOregonand north-central Nevada: Jour.
Geophys.Research,v. 89, p.8616-8628.Rytuba, J. J., Hernandez, A.M.,
Rye, R. O., Dean, J. A., andArribas, A., Sr., 1989, Genesisof
Almaden type mercury de-posits, Almaden, Spain labs.: Internat.
Geol. Cong., 28thWashington, 1989, Abstracts,v. 2, p. 2-741.Saup,
Francis,1973, La gologie du gisementde mercure d'Al-madn: Sci.
Terre, Nancy, Mm. 29, 342 p.Sillitoe, R. H., and Bonham, H. F.,
Jr., 1990, Sediment-hostedgold deposits: istal productsof
magmatichydrothermal ys-tems: Geology, v. 18, p. 157-161.Sprecher,
T. A., 1985, Wallrock alteration, vein structure, andpreliminary
luid inclusion tudies,Gooseberrymine, StoreyCounty, Nevada:Unpub.
M.S. thesis,Univ. Nevada-Reno,92p.Tingley, J. V., and Bonham, H.
F., Jr. , 1986, Sediment-hostedprecious-metal eposits f
northernNevada:NevadaBur. MinesGeology Rept. 40, 103 p.Vidal, C.,
and Cabos,R., 1984, Estudiogeolgicoy camparia ilotode geoqulmica n
el distrito minero SantaBfrbara,Huancav-elica: Buenaventura
ngenieros,S. A. for SociedadMinera ElBrocal S. A., private rept.,
59 p.Wallace, A. B., and Roper, M. W., 1981, Geologyand
uraniumdepositsalong the northeasternmargin, McDermitt
calderacomplex,Oregon: Am. Assoc.Petroleum GeologistsStudies
nGeology, v. 13, p. 73-88.Wallace, A. R., 1989, The Relief Canyon
gold deposit, Nevada:A mineralized solution breccia: ECON. GEOL.,
v. 84, p. 279-290.
Yates, R. G., 1942, Quicksilver depositsof the Opalite
district,Malheur County, Oregon, and Humboldt County, Nevada:U.S.
Geol. Survey Bull. 931-N, p. 319-348.Yates,R. G., Kent, D. F., and
Fernandez-Concha,J., 1951, Geol-ogy of the
Huancavelicaquicksilverdistrict, Peru: U.S. Geol.Survey Bull.
975-A, 45 p.
