'THE GEOLOGY AND MINERAL RESOURCES OF DHUFAR PROVINCE, MUSCAT AND OMAN' [‎26r] (41/96)

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my tour was that the limestones of the Jabal Qara were of middle to
upper Eocene (not lower than Lutetian) or equivalent to the Kirthar
of Sind. There would thus be a hiatus between the limestones on
Jabal Samhan and those of Jabal Qara, which requires attention
stratigraphically as well as structurally in the geology of Dhufar.
51. I concentrated my attention on the lower strata and came
down the valley to the south-east from under the main scarp of the
Samhan hills north-west of Murbat. The khaki-coloured splintery
shales are underlaid by earthy sandstones and these beds appear to
dip westwards and to belong/to the same series as the sandstones
on the shore of Murbat bay where the ‘oil’ was found. If this is
correct then an anticlinal feature is present because the sandstones
of Murbat bay definitely dip south-west into the sea at 5 to 10 degrees.
There may be a strong fault between the sandstones and the meta-
morphics of Jabal Ali near Murbat, since at the ‘oil’ exposure (north
side of Jabal Ali) the sandstones trend north-north-east and dip at
70 degrees westward near their contact with the metamorphic rocks,
but in a few yards the strike becomes north-north-west with only
15-degree westerly dips, and at the ‘oil’ locality, a few yards further
west, the strike is north-west to south-east and the dips south-west
at from 10 to 5 degrees. I found no fossils in any of the beds exposed
in the Jabal Samhan scarp facing Murbat (the western part of this
important scarp). Nor could I recognize more than the following
two sets of strata—an upper series of limestones perhaps 1,500 feet
thick with lithographic A lithograph is an image reproduced from a printing plate whose image areas attract ink and non-image areas repel it. limestone in the basal section, and a lower
series of brown to greenish coloured strata with an argillaceous facies
above and earthy sandstones below (with some reddish gritty beds
at the junction between the two series, but probably belonging to the
lower and not extending to the westward limit of the scarp face).
52. On the morning of the 13th February, accompanied by
Khan Bahadur Ahmed Sheeb Ali, I went to see the ‘oil’ occurrence
on the shore of Murbat bay north of the Jabal Ali. The beds
involved are argillaceous sandstones, brown in colour and with a
little mica present, in beds 12 to 18 inches thick with thin shaly
partings between the successive beds. The tide was out (and rises
5 to 6 feet when high). As may be imagined with such rocks,
covered at full and exposed at low tide, the possibility of a slight
oil seepage remaining at one spot for years is unlikely unless the
seepage is strong. Those with me insisted that oil had been noted
and found (by soaking up in a cloth and squeezing into a bottle)
which smelt strongly of ‘kerosene’. I was unable to detect any
definite smell of petroleum, and from the position of the rocks and
their structural and stratigraphical consideration I was inclined to
the view that a tin or barrel of oil had come ashore and leaked on
these rocks and left traces of oil which observant fisherfolk would
soon notice. However, the case is ‘ non-proven ’ and will be discussed