Mineral Resources Potential - Geothermal Resources

Metallic Minalals 1 13 ,.
3.8 Base Metals (Copper, Zinc, Lead, Molybdenum, and
Wolfram) deposit
Copper occurrence
Copper can be found as native copper in mineral form. Minerals
such as the carbonates azurite'(~a(~0&(0~) and maiachite
(CU~CO~(OH)~) are sources of copper, as are sulfid& such as
chalcopyrite (CuFeSz), bornite (CusFeS4), covellite (CuS),
chdcocite (Cu2S) and oxides like cupriti: (Cy20). Most copper ore
is mined or extracted from large open pit mines in copper porphyry
deposits that contain 0,4 to 1.0 % coppe'. Examples include:
Chuquicamata in Chile and El Chino mine in New Me&. The
average 'abundance of copper found within crustal rocks is
ap~mximately 68000 parts per billion by mass, and 22,000 parts
per billion by atoms (Jensen and Batman, 1979).
Copper is found in association with many other metals wnd deposit
styles. Commonly, copper is either formed within sedimentary
rocks, or associated with igneous rocks. The world's major copper
deposits are formed within the granitic porphyry copper style. The
source of the copper is generally considered to be the lower crust
or mantle where the granite melt forms. The copper is enriched by
processes during crystallisation of the granite and forms as
chalcopyrite -a sulfide mined, which is canied up with the
@mite.
Sometimes granites erupt to suface as volcanoes, and
copper minerdisation foms during this phase when the granite and
volcanic mks cool via hydrothd circulation. Sedimentary
. copper forms within ocean basins in sedimentary rocks. Generally,
this forms by brine discharging-hm deeply buried sediments into
the deep sea, and precipitating cupper and often lead and zinc