3)
Further above in this sequence other quartz-Kyanite micaschists fol-
low. The may show a preserved cross-bedding.ln thin section (2M 7) a persi-
stent reequilibration of Kyanite into white mica and Mg-chlorite, (white mi-
ca rims around Mg-chlorite) is observed. Quartz, white mica t phlogopite,
Mg-chlorite and Kyanite are the dominant mineralogical components.
The overall sequence (dipping 20°-22°) is transected at low angle
by a penetrative foliation whith the morphology of a particularly well deve-
loped crenulation cleavage in the uppermost levels (above QtB) and dipping
25R-955°.
The QtC hematite-layered micaschists (ZM 9 and ZM 10) are rich in
kyanite, (rimmed by white mica), Mg-chlorite and phlogopite and provide a
record of the original bedding, though distorted and cleaved in the hematite
-rich layers.
2.2. Kimale Hill
Another preserved portion of the Lower Roan sequence overlying the
basement has been visited at Kimale Hill. The metamorphosed stratigraphic
sequence here rests on top of metagranites, which preserve as magmatic relics
K-feldspar (microcline), plagioclase and white mica. Metamorphic minerals
as a a newly recrystallized white mica rimming the formers and green -brown
form without a significant foliation (ZM 11).
Similar!ly scapolite blebs (Dipyre) and an un oriented aggregate of
white mica replace the original plagioclase.
The metasedimentary sequence begins with a one meter thick-white mi-
ca Mg-chlorite, phlogopite-Kyanite schist with augen-like aggregates of an-
nealed quartz (up to 4-5 mm). This schist (ZM 12) is strongly foliated sub-
paralle,l to the contact with the granite; no evident layering is visible
across the boundary, but the oriented inclusion trails (qtz-white mica) pre-
served within the large laths of randomly oriented Mg-chlorites and the no-
dular shape of the quartz favour a long microstructural history of this rock
involving succesive stages of intense refoliation and recrystallisation.
Therefore this rock can well be interpreted as a blastomylonite.
These micaschists are overlain by other white mica, phlogopite, Mg-
chlorite, Vanitec quartz-schists (ZM 14 - ZM 15) with Uranium showings. They
contain as accessory minerals rutile, turmaline, hematite and apatite. The
overlying level is a cross-bedded quartz-kyanite-micaschist (QtB) with phlo-
gopite and again a Mg-chlorite sitting across the prominent mineral layering
and with a pronounced optical intracrystalline deformation. The assemblage
of the metasedimentary cover at Kimale and Chifubwa Gorge show the persistent
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