kuliah 4 - endapan porfiri

ENDAPAN TIPE PORFIRIENDAPAN TIPE PORFIRI

Hedenquist et al., 1996

PTFI END 2011 RESERVESPTFI END 2011 RESERVES

55

GRASBERG GEOLOGY – PRE MINING

HISTORYHISTORY ERTSBERG ERA:ERTSBERG ERA:

– 1934: Ertsberg discovered – Jean Jacques 1934: Ertsberg discovered – Jean Jacques DozyDozy

– 1960: Forbes Wilson expedition, explores 1960: Forbes Wilson expedition, explores ErtsbergErtsberg

– 1967: COW I signed1967: COW I signed– 1973: Production began on Ertsberg skarn1973: Production began on Ertsberg skarn

GRASBERG ERA:GRASBERG ERA:– 1988: Grasberg discovered (Dave Potter)1988: Grasberg discovered (Dave Potter)

Big investment: high risksBig investment: high risks Need guarantee for long term Need guarantee for long term

investmentinvestment– 1991: COW II signed1991: COW II signed

The new COW with a 30-year term and The new COW with a 30-year term and two 10-years extensions is signedtwo 10-years extensions is signed

COW II is more beneficial to Indonesia.COW II is more beneficial to Indonesia.

Dozyand his team

Forbes Wilsonand Delos Flint

Grasberg Pre-mining

GrasbergOpen-pit

Ertsberg Original Outcrop Grasberg

Ertsberg

Early Original Photos

Ertsberg