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location by major faults as in the environs of Empangeni. The areas underlain by granitic
rocks can be at high elevations on the interfluves between rivers, and much lower in the
river valleys and basins.
On either side of this granitic belt in the centre and south of the province there is usually
a somewhat elevated zone of Natal Group sandstone, which, to the east in the faulted
coastal margin, becomes mixed with areas of the Dwyka TilIite Formation, the
Pietermaritzburg Shale Formation and the Vryheid Formation - these formations in general
occurring in this sequence in a seaward direction; the Vryheid Formation not being found
to any significant extent south of Durban. To the west, the Dwyka Tillite Formation
constitutes a relatively narrow zone, in places particularly to the north, if resting directly
on granitic rocks without the intervention of the Natal Group sandstone. Sequentially and
altitudinally to the west, the mudstones, shales and sandstones of the Pietermaritzburg
Shale, Vryheid, Volksrust and Estcourt formations occur - further westthese being overlain
by the mudstones, shales and fine-grained sandstones of the various formations and
subgroups of the Beaufort Group. Forming the highest part of the province on its central
and south western boundary, is a narrow steep zone consisting of the Molteno, Elliot and
Clarens formations, which are topped off by the thick pile of Drakensberg basalts. In the
north east of NatallKwaZulu, the Karoo Supergroup rocks are faulted and flexed down in
the lebombo structure, the equivalent of the Drakensberg Formation basalt here being the
letaba Formation basalt which underlies the erosional trough of the lowveld. The
overlying erosionally resistant rhyolite and dacite of the Jozini Formation forms the long
linear elevated feature of the lebombo Range to the east thereof, beyond which it
underlies the Zululand Coastal Plain.
On the western margin of the Zululand Coastal Plain, Cretaceous marine sediments of the
Makatini Formation are exposed, overlying the Jozini Formation rhyolite and dacite, this
being successively overlain by the gently-dipping Msinene and St lucia formations. These
marine formations of Cretaceous age are covered by a veneer of unconsolidated Tertiary
and Quaternary sediments of the Uloa, Bluff and Berea formations, as well as by the
KwaMbonambi Formation - the latter being re-distributed cover sands of Holocene age.
The distribution of all these formations on the coastal plain shows a marked north-south
alignment parallel to the western margin of the plain, at the foot of the strongly linear
lebombo structural feature.