Mineral Resources Potential - Geothermal Resources

Platinum deposits in Ethiopia
Mcmllic Minrrals 73
Mineralized mdc-ultramafic rocks in Ethiopia occur as zoned
Alaskan-ts ultramafic bodies (e.g. Yubdo), ophiolitcs (e.g..
Kenticha) and possibly as xenoliths or dikes within the Trap basalts
covering most of the highlands (Mogessie et al , 2000).
Linear bodies of altered mafic-ultramafic rocks occurring
from Yubdo to the Tulu-Dimtu area were thought: to be part of an
ophiolitic sequence by Kazrnin ef al. (1 978). Recently, Mogessie ef
al., (2000) have suggested that these rocks were intruded into a
magmatic rift or back-arc basin. The main rock units of the Yubdo
area are dunites at the core, surrounded by peridotite and
hornblende-clinopymxenite; an outcrop pattern typical of Alaskan
type deposits.
The Kenticha belt in the Adola granite-greenstone terrain is
dominated by ulmmafic rock6 with subordinate amphibolites,
biotite schists, n~inor graphitic schists, and marbles, Based on
geological field relations, geochemical data and PGElchondrite
normalized plots, the Kenticha ultramafic rocks are considered to
be ophiolites (Mogessie et a/., 2002). Detailed ore reflected
microscope and electron microprobe analyses of chromite rich
layers within the Renticha rnafic-ultqafic units have been made.
PGM's such as laurite (RuS2) with a composition varying between
R~32.390~
I -71 h0.61 S62.12 and RUZ~
99 @I 5 1 Iro.70 S65.42, and ~rflall
concentrations of Rh and Pd have been documented for the first
time. In comparison to the Yubdo m&c-ultramafic rocks, the
Kenticha ultrarnafics are rich in chromite suzd the small PGM
grains are most of the time located at the rims of zoned chromite
grains in contact with chlorite andfor serpentine. Furthermore.
most of the PGM in Yubdo are rich in Platinum whereas the
Kenticha are enriched in Ru, 0 s and Ir.