Mineral Resources Potential - Geothermal Resources

Metallic Minerals 81
and South Africa. Substantial quantities of tantalite pegmatite
north of South Africa have started to be- mined in March 200 1. Of
all these occurrences, remarkably the richest tantalite deposit, more
than 70% of Ta205, is so far known to be present in E!hiopia
(Solomon and Zerihun, 1 996),
Geology af the Kentichi frmntollam-besuing pegmatite depmit
The rare metal occwrences in Kenticha are hosted in a long ma
Ihw Kenticha belt. The Kenticha, belt extends for over 100 lun
[from Katawhicha Mountain on the south to the left bank of the
Genale River on the north). The pegmatites in the Kenticha raremetal
field are genetically related to dome- and lens-shaped
differentiated granitic and pegmatitic intrusions along a discrete N-
$ fault and shear system, including biotite granite, two-mica
granite and daskitic granite. The granitic pegmatite, emplaced by
intruding the ultramafic suite, oc~urs within a large serpentinite hi11
, that covered about 9 km2. m
These post-orogenic intrusive are supposed to be h"e^ parent
rocks of the rare-metal enriched pegmatites occurring within the
field, mged in zonal patterns around the source granite and
following a N-S trending regional fault and shear system. The
post-tectonic granite, =-metal bearing pegmatites and accasional
alaskitic granite are widely developed in the fom of stock or dikes
varying from sevd kilometers to a few meters in width. N-S
trending structure is believsd to have controlled the localization of
the rare metal bearing pegmatite and associated acidic granitoid,
The army of pegmatites follows N-S trending find&. In addition to
the principal N-S trending faults, there are two younger faults
systems trending NESW and NW-SE. The intersection of these faults
with those trending N-S appears to be the most favorab1a site for the
emplacement of the late stage diffemhtes conbhq
concentrations of the memetal ores (Solomon and Zerihun, 1996).