File 1450/1919 ‘Mesopotamia & Kurdistan: Geological Reports on’ [‎191v] (405/522)

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folding of post-pliocene age which is probably still continuing. Of the
remainder the following merit particular notice : ■
The Naft Khana Anticline.
The Chah Surkh Anticline.
The Qasr-i-Shirin Anticline. > |
The Qalah Sabzi Anticline.
{14) The Naft Khana Anticline. {See Map No. 1)—The great import
ance of this anticline is due to the numerous and copious seepages of oil which
escape from the beds of which it is composed. This particular aspect will be
dealt with under “ Evidence of Petroleum.”
The fold is one of great regularity and has been traced for over 17 miles to
where it dies out near Kani Masi. Its main features are its asymmetry and
the reversed strike fault which coincides with the axis of the fold for a mile and
a quarter; both are clearly shown in plan and section in Map No. 1 . It
pitches down in both directions along the axis and so may correctly be described
as elongated dome structure. Gypsum of the Lower Ears Group is exposed first
in the Ab-i-Naft river, which here marks the frontier, and continues in a
North-Westerly direction for 2J miles when owing to pitch the Middle Ears
closes in over it. The Middle Ears likewise pitches under the Upper E'ars
| mile further along the strike.
The reversed fault is a minor dislocation only and wall probably be found
to have little effect on the oil capacity of the anticline; if the first test is suc
cessful future locations can be made on the upper fault block in such positions
that the bore holes will not cross the fault plane, However, with a view to
taking every possible precaution, the first location has been cliosen clear of the
fault.
{15) The Chah Surkh Anticline.—This anticline is a simple asymmetrical
fold, the steep flank dipping at 70 deg., and the gentle flank at 15 to. 18 deg.,
while the axis pitches down in both directions from a central point. It is
therefore another example of asymmetrical elongated dome structure, one. of
the most desirable structures for petroleum. Weathering of the overlying
rocks has exposed a few feet of Low^er Ears strata in the core of the dome. The
steep flank rapidly flattens out aw r ay from the axis, and there is no faulting.
The Anglo-Persian Oil Co. had three wells on this anticline, of which some
details are given under “Evidence of Petroleum.”
{16) The Qasr-i-Shirin Anticline.—-This is a structural feature of some
physical importance, since the ridge Sumhulaq Kuh of over 2,000 feet altitude
is directly due to anticlinal uplift and faulting, and, the Lower Ears gypsum
exposed is of considerable extent for this district both along and across the
strike. The fold is asymmetrical and has fractured along its axis under tensde
stress, giving rise to an overthrust fault which has carried the gypsum beds
across vertical Middle Ears to where they have come to rest on Upper Ears
strata. The fault commences at a point 3 miles South-East of Qasr-i-Shirin,
and the town itself stands right on the fault plane.
{17) The Qalah Sabzi Anticline.—The Bakhtiari rocks of Qalah Sabzi are
thrown into an asymmetrical fold whose flanks dip at 60 deg. and 20 d e g.,
respectively. This anticline is mentioned only because it is on the strike of oil
seepages reported on reliable authority near Harjik on the Ab-i-Gilan, 10 5-J_r e ®
away in Persia. As the anticline has certainly pitched to the North-West
here, any possible oil is very probably out of reach of the drill on the Mesopo
tamian side of the frontier.
(18) Western District.—While a large part of Lower Mesopotamia is the
result of Becent alluvial deposition unaccompanied by diastrophism, epeirogenic
movement existed and continued into late pliocene or post-pliocene times, as is
demonstrated by the uplift of large tracts of marine Koweit Series strata into
dry land. In fact this movement may still be continuing and assisting the
dessication of the Persian Gulf The historical term used to describe the body of water between the Arabian Peninsula and Iran. .
Westwards from Baghdad the Asmari Limestone is first seen at Hit, and
although locally it appears horizontal, actually it is in the form of a roa

File 1450/1919 ‘Mesopotamia & Kurdistan: Geological Reports on’ [‎191v] (405/522)

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File 1450/1919 ‘Mesopotamia & Kurdistan: Geological Reports on’ [‎191v] (405/522)

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