'THE GEOLOGY AND MINERAL RESOURCES OF DHUFAR PROVINCE, MUSCAT AND OMAN' [‎34r] (57/96)

41
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both places are similar and have been identified as upper Eocene
(probably Bartonian) forms. These limestones mdy not be the
highest beds on the Qutun or watershed of the Jabal Qara, but
are referred to as the Qara (A1 Qutun) limestones (9), because I
think they will be found in all the upper valleys if not forming the
actual open upland, karstland, of the Jabal Qara. Included among
the fossils of these beds are certain forms indicating the uppermost
Eocene (Yaw stage) of Burma (see paragraph 69).
Miuoutic Coastal Limestones
75. ' These porous, shelly limestones are seen all along the coast
from Murbat to near Risut, usually within a distance of about 2 to
2 | miles from the beach. They are very similar to the Porbandar
limestone of Kathiawar and other coastal Miliolitic limestones at the
head of the Arabian Sea from Sind to Dhufar. The occurrences
near Okad (Augad), Salalah, Hafa and so on eastwards to Takah and
to Murbat are in bedded deposits 8 to 20 feet thick with the separate
layers each from 12 to 18 inches thick. The dips at Salalah are
south at about 5 degrees, and the rock is sufficiently consolidated
(cemented with carbonate of lime) to be hard enough for a somewhat
friable freestone for building purposes. It is difficult to decide the
age of the beds and their origin, but studies elsewhere (Kathiawar)
by J. W. Evans (1900) resulted in most of these Miliolitic limestones
being regarded as ‘ wind-borne ’ (aeolian), littoral deposits of relatively
recent age. The material is chiefly the cases of small foraminifera
and fragments of shells and corals. In the case of the Miliolite
limestone from near Salalah (see paragraph 69) many of the fossils
appear to be uppermost Eocene forms (Yaw stage), but as the aggre
gate is almost entirely detrital material it must be assumed that
the foraminifera and other fossil fragments represent material
derived from the rocks exposed within the drainage of the Dhufar
coast. As the oldest fossil remains are not older than uppermost
Eocene it may be concluded that such rocks exist or existed, in this
area and suffered or are suffering erosion. In my. opinion the
Miliolite is probably not newer than Pleistocene and might be as old
as Pliocene and the uppermost Eocene has been removed and some
what older rocks, upper to middle Eocene, are now present m the
existing drainage area of the Dhufar plains.
W. Ghaiz Conglomerate and Dahaq Tufa
76. The conglomerate terrace now subject to erosion by the
Nagar Ghaiz wadi A seasonal or intermittent watercourse, or the valley in which it flows. is upwards of 30 feet thick and is regarded as no
younger than Pleistocene. The pebbles and boulders are large y o
limestone, with some sandstones, and cemented with tulaceous
(calcareous) precipitates. The evidence of this erosion suggests