"الجيولوجيا والموارد المعدنية في كلٍ من محافظة ظفار ومسقط وعُمان" [و‎‎٢‎٣] (٩٦/٣٥)

21
A^nish
large
Lenta-
Ayun
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green
must
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e at a
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. are, I
t with
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ilah we
rds for
mtered
howing
s there
were isolated conical hills of about the same height but of small
extent, resembling earth-pillars somewhat and suggesting that each
represented the remnant of a single formation, as so many outliers.
Next the plain itself was bare but cut by flat-bottomed ravines,
in the sides of which almost horizontal beds were exposed. In most
of these exposures, usually 2 or 3 feet under the top layer of lime
stone, there was an absolutely white bed resembling chalk, some
times 3 feet thick and often of much greater thickness. And so we
came to a specially wide and deep ravine or wadi, in the sides of
which there were successive beds of white, powdery or chalky lime
stone. We descended into this wadi to camp at the water-hole of
Hanun, a pool in a deep channel of the limestone floor of this wadi.
It was already dusk and cold with a wind up the dry wadi from
the north. Next morning ( 8 th February) Sheik Sail bin Garwah
left for Haloof Dhar (Ath’Air?) to bring me specimens, while I
made an examination of the sides of the wadi in which lies the
Hanun water. It is definitely salt but not nauseatingly so, and would
be appreciated by very thirsty people. The water is esteemed by
the people, but I could not show the same appreciation and drank
from what I had brought from Ayun (although that has a slightly
muddy taste).
39. The signs of flood water at Hanun indicated a stream over
3 feet deep and perhaps 400 feet across. This section with an
assumed velocity of 1 J feet per second gives a discharge of 1,800
cusecs, which if maintained for 12 hours represents a volume of
nearly 72,500,000, cubic feet or 450,000,000 gallons, or somewhat
greater than that of Ayun. In the morning light the sides of the
wadi are a snowy white with the chalky strata well exposed. The
height of the plain above the wadi is perhaps 120 feet, and near
the top the' chalk ’ bed (it is a pure dolomite actually) is characterized
by containing irregular concretions of flints, separate but parallel
to the bedding. Irregularly shaped flints also occur in the bedding
plane. In both cases the flints vary from 5 inches to large masses
up to 12 or 15 inches in length, and are closely associated with the
porous-looking granular-textured ‘chalk’ (dolomite) in which they
occur as segregations. They have all the appearance of secondary
development and, indeed, the dolomite itself seems to have been
formed in situ from an original (fossil) limestone, after the marine
deposit was exposed to weathering by percolating meteoric waters.
It appeared to me that in this Qarn Shaiba region, the processes
might still be in progress under the surface.
40. The limestones below the ‘chalk’ (dolomite) bed, which
is 6 to 7 feet thick, are harder but with friable-looking surfaces
from which casts of fossils, large gasteropods and echinoids, project
(these are not easy to extract without damage). Associated with
these fossils are numerous nummulites. In a lower bed of similar