| dc.description.abstract | The text describes the geology and the geochemistry of
part of the Pangani River Escarpment lying in north east Masai-
land, Tanzania. It is bounded by longitude 370 lSIE to the
west, Pangani river and a reservoir to the east and latitudes 30
42 I Sand 40 08 IS to the th d th t . 1 Th'
nor an sou respec ~ve y. e area
consists of three morphological units, nam-al y , the Pangan r
valley to the east, the escarpment and a plateau zone to the west.
In this study, an attempt is made to relate the geology to
the distribution of copper, nickel, lead, zinc and rare earths.
Assessment of possible occurrence of non-metallic minerals is also
made.
The roc~s in the area include a thick succession of
Usagaran rocks of Late Archean age which are comprised of
metasediments and metaigneous rocks. The rocks were later
subjected to intense folding and regional metamorphism which
produced features of great structural complexities. After long
periods of denudations and peneplanation, Tertiary downwarping
and Neogene faulting took place.
It was found that copper and nickel are favourably
associated with the metai~naous rocks whereas zinc and lead are
found in higher proportion~ in the metasediments. Rare earths
t~nd to acc.ompany these rocks·fn trace amounts. Metal relation
of Cu/Ni, Cu/Zn, CulPb was found to be unique fo~ each rock type
having a tendency to variation at different concentrations.
In the text bivariate distributions have been performed in order
to derive regression equations that are characteristic for the
main rock and soil types.
Copper stained rocks were found when this work was in
progress and the area has been proposed for further investigation.
Hinerals of possible kimberlitic origin were also found but
their mode of occurrence is still obscure. | en |
