Base-Metal Deposits of the Cordillera Negra Departamento De Ancash, Peru
Total Page:16
File Type:pdf, Size:1020Kb
Base-Metal Deposits of the Cordillera Negra Departamento de Ancash, Peru GEOLOGICAL SURVEY BULLETIN! 1040 Prepared in cooperation with the Ministerio de Fomento, lnstituto Geologico del Peru, under the auspices of the Interdepartmental Committee on Scientific and Cultural Cooperation with the American Republics Department of State Base-Metal Deposits of the Cordillera Negra Departamento de TAn cash, Peru ' By ALFRED J BODENLOS and JOHN A. STRACZEK GEOLOGIC INVESTIGATIONS IN THE AMERICAN REPUBLICS GEOLOGICAL SURVEY BULLETIN 1040 Prepared in cooperation with the Ministerio de Fomento, lnstituto Geologico del Peru, under the auspices of the Interdepartmental Committee on Scientific and Cultural Cooperation with the American Republics Department of State UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON • 1957 UNITED STATES DEPARTMENT OF THE INTERIOR FRED A. SEATON, Secretary GEOLOGICAL SURVEY Thomas B. Nolan, Director For sale by the Superintendent of Documents, U S Government Printin~ Office Washin~ton 25, D C. CONTENTS Pag£> Abstract---------------------------------------------------------- 1 Introduction------------------------------------------------------ 2 GeographY---------------------------------------------------- 3 TransportatiOn routes _____ -----________________________________ 7 LocatiOn of mmeral deposits_ _ _ __ _ _ _ _ _ __ _ __ _ _ __ _ _ __ __ _ __ _ __ __ __ _ 8 Prevwus geologic work_________________________________________ 10 Field work and acknowledgments________________________________ 10 GeologY---------------------------------------------------------- 11 JRock units---------------------------------------------------- 13 The sedimentary sequence__________________________________ 13 Pueblo Libre-Colqmpocro area__________________________ 15 Otherlocah~es________________________________________ 17 Sedimentary outcrops m volcamc terrane_________________ 19 The volcamc sequence______________________________________ 20 General descriptiOn and petrology_______________________ 20 Division of the volcamc sequence________________________ 24 Intrusive rocks____________________________________________ 27 General classrficatwn and distributiOn____________________ 27 Acid, or quartz-bearmg, mtruswns_ _ _ _ __ _ _ __ _ _ __ _ _ _ _ __ _ _ _ 29 Intermediate and basic mtruswns____ _ _ _ __ _ _ _ _ __ _ _ _ _ __ _ _ _ 32 Dikes and sills_ _ _ _ _ __ __ __ _ _ __ _ _ _ _ __ _ _ __ _ _ _ _ __ __ __ _ _ _ _ _ 36 Genetic relatwnsmps and age of mtruswns___ _ _ _ _ __ __ __ _ _ _ 37 Structure and metamorpmsm_ _ _ ___ __ _ _ __ _ _ __ _ _ __ __ __ __ __ __ __ _ _ _ 38 Glaciation____________________________________________________ 42 PhysiOgraphiC development_____________________________________ 43 Geologic history_______________________________________________ 44 Mmeral deposits___________________________________________________ 45 Environment of mmerahzatwn__________________________________ 45 MineralogY-----------------------------------~--------------- 47 Altered wall rock______________________________________________ 51 Composition of vems ___ ----------_ _ _ _ _ _ _ __ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 53 SummarY----------------------------------------------------- 55 Mmmg and economiC consideratiOns_____________________________ 55 Future possibihties and recommendatiOns_________________________ 58 Mmes and prospects_______________________________________________ 59 The southern area________ __ __ _ _ __ _ _ __ _ _ __ _ _ __ _ _ __ _ _ __ _ _ _ _ __ _ _ _ 60 Collaracra mme _ _ _ _ _ _ __ _ _ __ _ _ __ _ _ __ _ _ __ _ _ __ __ __ _ _ _ _ _ _ __ _ _ _ 6 0 Huancapetl mme_ _ _ _ _ __ _ _ __ __ _ _ __ __ __ _ _ __ _ _ _ _ __ _ _ _ _ __ _ _ __ _ 64 Pucaraprospect___________________________________________ 69 Cerro Puyhuan mme_______________________________________ 69 Coturcan mine____________________________________________ 71 Tarugo mine---------------------------------------------- 72 Prospects and mmes m Cerro Pucar__________________________ 72 Prospects on the northwest flank of Cerro H uancapetL __ _ _ _ __ _ _ 74 Wilson mme and prospects---------------------------------- 75 l:U IV CONTENTS Mines and prospects-Contmued The southern area-Contmued Page Tuctu mmes and prospects_________________________________ 77 Jesus-Magdalena prospect ____________________ -------_______ 80 La Recuperada and El Lucero prospects______________________ 81 San Ildefonso, La Improvisada, and Mariscal mmes____________ 82 Se:fior de Soledad and Fernandita prospects___________________ 85 Mme on Cerro Pillac_______________________________________ 86 San VIcente mme___ _ _ __ __ __ __ _ _ __ __ _ _ _ _ _ _ _ _ __ __ _ _ __ _ _ __ __ _ 86 Cerro Pamcocha prospect___________________________________ 87 Cerro Mulluoctu prospects__________________________________ 87 Santa Elena mme_____ _ _ __ _ _ _ _ _ _ __ _ _ _ _ _ _ __ __ __ _ _ _ _ _ _ __ __ _ _ _ 88 Mercedesprospects---------------------------------------- 94 Santa Cruz depomts---------------------------------------- 96 The central area_______________________________________________ 97 Jecanca m1ne--------------------------------------------- 97 Bohche mmes and prospects _________________________ ------_ 102 Tres Hermanos and San Juan prospects______________________ 104 El Carmen mme_ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 104 Cerro Maco mme_ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 107 Fray Martin, J atuncaca, San Judas, and other prospects_ _ _ _ _ _ _ 108 Quebrada Qmrhuac mmes_ _ _ _ _ __ __ _ _ _ _ __ __ _ _ _ _ __ __ __ __ _ _ __ _ 111 Cerro Huarancayoc prospect________________________________ 112 Humchos and Mediza prospects----------------------------- 113 PucaJirca prospects__________________________________ _ __ _ _ _ 115 Hmscor and Yanac6n prospects_____________________________ 115 H uallpac mme _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 117 Mac6nm1ne---------------------------------------------- 118 Cerro Plum1sa mme _________ ---- _ _ _ _ _ _ _ _ _ ___ __ _ _ _ _ __ __ _ _ _ _ _ 119 Laguna Shaullan prospects__________________________________ 120 Uchco mmes and prospects--------------------------------- 120 Cerro S1ernen prospect_____________________________________ 124 Buena Cashma and Mangan mmes__________________________ 124 Mmes and prospects, Pueblo Ltbre district____________________ 127 Buena Fe mme _________________________________ -- _ _ _ _ _ 128 Atahualpa mme __ -- __ -------------- __ -- __________ ----- 129 Santa Rita mme ____________ -- ______ ------ _ _ _ _ __ ___ _ __ _ 130 Ammus and Socavonera prospects and Santa Rosa mme____ 130 Santa Damiha prospect _____________ ------ ____ ------___ 130 Rayos-X prospect ________ --- _______ --- ____ --- _______ -_ 131 Cerro Chaqmcocha mme __________________ ---- ____ -------- _ 131 Cerro Chacayprospects------------------------------------ 132 Colqmpocro mme ___________________________ -- __________ -- _ 132 Chacuopampa mme___ ____ _ _ ____ __ _ _ __ __ _ _ _ _ _ _ __ _ _ _ _ __ __ _ _ _ 134 Prospect on Cerro Aqmlpampa ___________________________ -- _ 135 Capalo mme_ _ _ _ _ _ _ __ __ __ _ _ __ __ _ _ ____ __ _ _ __ ____ _ _ _ _ __ __ _ _ _ 135 Prospects on Cerro Ananpunta ____________________________ - _ 136 Santa Rosa mme_ _ ___ _ _ __ _ _ __ _ _ __ _ _ __ _ _ _ _ __ __ _ ___ __ _ _ _ _ __ _ 136 Ingemo mme ___________________________ ------ __________ -- _ 137 Piedra I man mme _______________________________________ - _ 138 Honcaprospect___________________________________________ 139 Prospect south of Honea mme_______________________________ 140 RumiChaca mme ________________________________________ - _ 140 Ancushtrancaprospect------------------------------------- 141 Cerro Putacaprospect------------------------------------- 141 CONTENTS V Mmes and prospects-Contmued Page The northern area--------------------------------------------- 142 Cerro Paltac prospects ___ - ______________________________ - _ _ 142 Cerros Culebrllla mme _____________ -- ___ ---__ ---___ -------- 143 QuebradaAncushprospects--------------------------------- 145 Portach6n mmes and prospects------------------------------ 146 Rumwruz prospects ________ ----- __ ------------------------- 147 D10medes mme and prospects_______________________________ 147 Cerro Manaucro mmes and deposits_________________________ 148 Cerro Patara mmes---------------------------------------- 149 Patara rome _____________________ ------ __ ----_-------- 151 San Antomo mme ______________________________ -- __ --- 154 San Pedro mme ____________________________________ --- 154 MisiOnera mme ___________ ----- _____ ---- ________ ------- 155 Mmes and prospects east of the divide ________________ --- 155 Quebrada Manto Alto mmes and prospects _________________ - _ 156 Literature cited ________ ------_____________________________________ 159 Metric eqmvalents_______ _ __ ____ _ _ __ __ __ _____ _ __ _ _ ___ _ _ _ ____ _ _ __ __ _ 161 Index------------------------------------------------------------ 163 ILLUSTRATIONS [Plates in pocket except as indiCated] PLATE 1 Reconnaissance geologiC map of part of the Cordillera Negra, Peru, showmg locatwn of mmeral deposits 2 A VIew of rocks of Cretaceous age overlam by rocks of the volcamc sequence; B, view of wedgmg of volcamc beds, Cerro Condorcocha __________ ------_______________ Facmg 26 3 V1ew of maJor unconformity between folded rocks of Cre taceous age and shghtly folded volcamc rocks of Tertiary age---------------------------------------------