Accha

GEOLOGIA Y PROGRESO DE LA EXPLORACION DEL YACIMIENTO DE ACCHA

GEOLOGIA Y PROGRESO DE LA EXPLORACION DEL YACIMIENTO DE ACCHA
DEPARTAMENTO ARTAMENT CUSCO SCO, EN EL DEPARTAMENTO DEL CUSCO, PERU
G. D. CARMAN, P. NICHOLSON, S. IANOS, E. BERNUY, C. SALINAS, W. ORMSBY, AND J. PERKINS PASMINCO EXPLORATION

R ESUMEN
El yacimiento de Accha está situado en la cordillera del Perú sudoriental, a unos70 km al sur del Cuzco y a unos 100 km al noroeste de la mina de cobre de Tintaya. El nombre local de uno de los prospectos es Titiminas, que significa ‘minas de plomo’. La propiedad fue amparada en 1994 por Southwestern Gold Corporation y actualmente es un joint venture con Savage Exploration del Perú, subsidiaria de Pasminco, que es el operador del proyecto. La mineralización estratoligadaocurre dentro de la formación calcárea cretácica Ferrobamba en unas brechas intraformacionales, la mineralización conocida hasta ahora consiste en minerales oxidados de zinc que demuestran un potencial de sulfuros en profundidad. Se considera que este yacimiento es del tipo de Mississipi Valley. El yacimiento contiene un recurso indicado del orden de los 9 MT con 9% de Zn en menas oxidadas de Zinc.holes during 1995-1996. They intersected high-grade zinc oxide mineralization in several of the holes but withdrew from the joint venture in 1997. In May 1998, Savage Peru signed a joint venture with SWG to explore the Accha properties. From August 1998 through January 1999, Savage completed twenty-four RC holes and ten additional diamond holes. By the end of this drilling campaign an indicatedand inferred zinc oxide-carbonate resource of 9 MT @ 9% Zn was estimated at Titiminas (Savage news release, 15 January 1999). Mineralization is considered to be of Mississippi Valley Type (MVT) and is hosted by a stratabound breccia and argillaceous limestone sequence about 100 m in thickness. Zinc oxide potential still remains open at Titiminas, while the sulfide potential at depth is yet to betested. These targets and several other prospects discovered in the area will be drill tested in future exploration.

TRAT ARBONATE EPOSITS STRATABOUND MVT CARBONATE-HOSTED DEPOSITS IN PERU
MVT-style zinc mineralization at Accha is hosted by cretaceous limestones of the Ferrobamba formation. Other Pb-Zn mineral occurrences in the district are known at Yanque some 30 km to the southwest (exploredrecently by Rio Tinto and Argento), as well as several other smaller shows. This contrasts to most of the known MVT occurrences in Peru, which are hosted by upper Triassic – lower Jurassic carbonates of the Pucará Group, the largest known deposit being the SIMSA-owned San Vicente mine in central Peru (Fontboté and Gorzawski, 1990). Pucará-hosted MVT mineralization has been recently discovered inthe Department of Amazonas at Bongará.

EXPLORATI TION GEOLOGY AND EXPLORATION PROGRESS OF THE ACCHA ZINC DEPOSIT, CUSCO, PERU DEPOSIT, CUSCO SCO, INTRODUCTION
The Accha zinc project is located 70 km south of the city of Cusco in the cordillera of southeastern Peru, about 100 km north west of the Tintaya copper mine. It lies at an altitude of between 4000 and 4400 m.a.s.l. The project is a jointventure between Savage Exploration del Peru (now a subsidiary of Pasminco Limited) and Southwestern Gold Corporation (SWG). Pasminco is the operator of the project. Small lead showings at the Titiminas prospect possibly date back to Inca times (‘Titi’ means lead in the Quechua language). SWG staked the proper ty in 1994. Cominco drilled five diamond

ACCHA REGIONAL GEOLOGY
The regional geologyis shown in Figures 1 and 2. Basement rocks in the region belong to the Jurassic-Cretaceous Yura Group consisting of black shales, quartzites and minor limestones. These rocks are broadly contemporaneous with the Chicama and Goyllarisquizga Groups of north and central Peru. Basement rocks

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G. D. Carman, P. Nicholson, S. Ianos, E. Bernuy, C. Salinas, W. Ormsby, and J. Perkins
FIGURE 1...