'File 35/64 III Minerals in Oman. Madrasai geologists' researches' [‎16v] (41/276)

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The coal (" Sur coal") belongs to the uppermost 100 feet or so of the
Description of Oman Tertiaries, and is presumably of Upper Miocene age.
coal exposure. it occurs in a hilly country situated from 10 to 12 miles S.-E.
of Wadi A seasonal or intermittent watercourse, or the valley in which it flows. Palij and approximately 25 miles from Sur.
In the coal district the Miocene series form an open syncline, the axis of
which coincides roughly with a broad valley running S.E.-KW. Into this
main valley lead a number of small ravines from S.W., and in one of these
the outcrop of coal, which I inspected, occurs.
This outcrop is as follows :—
The ravine is from 70 to 150 feet wide and is bordered by steep walls of
rock. On the S.E. bank, at a few hundred yards from the main valley,
the coal exposure is met with, which has a length of 22 yards. The beds dip
down the ravine, their dip being steeper than the gradient of the former. The
seam, therefore, disappears towards the main valley under the surface, while it
rises out of the ground up the ravine (S.W.^ so that the base of the coal
is exposed at the S.W. termination of the outcrop. Here the seam is
concealed by debris for a short distance, under which it apparently thins out,
as it does not re-appear higher up the ravine. Nothing but an unworkable
bed of carbonaceous shale was found in this direction.
The coal is underlain by an ochrey shale, while the beds immediately over
lying the coal consist of canbonaceous shale of several feet thickness.
Above this follow shaly and concretionary limestones, which rise in a
perpendicular wall of from 50 to 60 feet. The seam is at the outcrop 4 8"
thick.
From this exposure nine coal samples were taken and tested in the Labora
tory of the Geological Survey Office. As the rocks were over-
Sampies. hanging, it would have been impracticable to dig far into the
seam. The samples, therefore, had to be taken from the surface, where the coal
was to a certain extent weathered. Two
* See p " 3 ' of the samples,* mz. y D. 50 and D. 49, are
from the top of the seam, two (D. 67 and D. 66) from the base, all the rest
are from the middle of the seam. The history of B. 37 is unknown. I received
it from a native, but am not sure whether it comes from the same locality or a
different one.
As to the composition of the coal compare the accompanying table, page
Composition 3. The first group of tests shows the percentage of moisture,
of coal. volatile matter, fixed carbon and ash. The second gives the
composition of coal of which the moisture has been extracted before assaying.
The samples gave all much the same results. There is, therefore, no
marked difference in the composition of the seam either vertically or
horizontally.
similar to The Sur coal can best be compared to Assam coals as shown
Assam coal. below, page 4