File 1450/1919 ‘Mesopotamia & Kurdistan: Geological Reports on’ [‎192r] (406/522)

gentle dome, since in all directions except the North-West it is covered by-
deposits of the Koweit Series. All the low hills between Baghdad and Hit,
which rarely if ever rise to a height of more than 100 feet above the desert, are
formed by horizontal strata of this latter series.
At a point 2 miles West 25 North from Hit, a very small local fold was
V observed in the Asmari Limestone with the Koweit Series beds lying horizontal
on Asmari Limestone dipping at 25 deg. Apart from the unmistakable uncon-
formability, the fold was too small and ill-defined to give any clue to the
general direction of folding here. Minute puckers of some 25 yards across
were observed in a few places in both the Asmari Limestone and the Koweit
Series, but except for the gentle dome structure already mentioned, the beds are
for all practical purposes horizontal.
Ihe Geological history of this region during Miocene times is obscure, but
of post-pliocene uplift with gentle warping of the earth’s crust, we have the
direct evidence above mentioned.
PART 5.—EVIDENCE OE PETROLEUM.
(19) Introductory. —The surface indications of petroleum, both Geologi
cally and Geographically, may be divided into two classes, namely, the oil in the
desert country near the Euphrates emanating from the Asmari Limestone, and
that of the Persian foothills which is found in the Pars Series. The former is
generally of the bituminous type with an asphaltic base (with the one excep
tion of Nafatah), while the latter is a lighter Gravity oil of praffin base. The
actual seepages examined are each described.
(20) Nafatah near Ramadi. —Nafatah (meaning oil) lies 12 miles West 38
North from Ramadi, and on the opposite bank of the Euphrates within 500
yards or so of the river. It consists of a hand dug well 10 feet deep in which
oil collects on the top of cold sulphurous water to the extent of 2 to 4 gallons
daily. The only rocks exposed in the district belong to the Koweit Series, and
the source of this seepage, which is probably the Asmari Limestone, is invisible
and buried under Alluvium.
{21) Abu Jir. —The pitch lake of Abu Jir (Arabic, Eather of Pitch) lies
29 miles West 25 South from Ramadi, or 20 miles from Khan Abu Rayat the
nearest place on the Euphrates. It is an impressive feature in the desert as it
is approximately a mile long and a third of a mile across, the whole of this
area being covered with pure bitumen or bitumen with earthy matter or sand.
The bitumen comes up from five main springs in a liquid form, accompanied
by cold sulphurous water and petroleum gas (probably methane, since it ignites
and burns with a non-luminous flame). It spreads out slowly, and though in
the winter months it is possible to walk any where on the lake, in the summer the
pitch is evidently soft enough to flow to some extent.
The only rocks exposed in the district are of the Koweit Series, but the
impregnation of asphalt in these must have migrated from the underlying
Asmari Limestone.
There is no surface evidence as to the structure of the buried Asmari
Limestone, but the fact that the main seepages of the Abu Jir lake are oriented
on a North-North-West line is significant. Again the fact that the seepages
of Jebhah and Ain-al-Awasil, 7 and 16 miles distant from Abu Jir, also lie on
a North-North-Westerly line passing through Abu Jir, seems to be strongly
confirmatory evidence, the whole suggesting an underground fold of the Asmari
Limestone with axis lying North-North-West, or more or less parallel with the
Persian Geological trend lines.
(22) Jebhah, —This place was not visited by the author, hut Lieut. Bourke,
then L. P. O. of Ramadi, who had been there, says that there is an oval space
of pitch half a mile long like Abu Jir, and with a small amount of sulphurous
water.
(23) Ain-al-Awasil. —This is reported to be similar to but very much
smaller than Jebhah.
{24) The extensive bituminous deposits of Hit have been famous
from early historical times. Herodotus mentions bitumen being brought to

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