File 1450/1919 ‘Mesopotamia & Kurdistan: Geological Reports on’ [‎134v] (283/522)

We propose therefore to divide the series into Lower and Upper Fars,
The Lower Fars can be divided into an upper and lowei sub-division, gypsum pi edonunatins^ in
the former and marls in the latter. The lower sub-division is composed chiefly of yellowish marls
with gypsum crystals, with interbedded bands of massive gypsum. Impel sistent beds of a concre
tionary, brown limestone, full of cavities also occur, flhe two bands of asphalt ai e situated at the
base of these beds, and the gypsum and limestone are also in places saturated with bitumen.
The upper half of the Lower Fars is composed chiefly of massive gypsum beds, with limestone
bands and a weaker development of the marls. At the top is a very pure band of white, shelly
limestone ; a very clear horizon, which should be of great sei vice in mapping.
We can as yet make no attempt at an accurate estimate of the thickness of these beds, but they
are probably of about the same thickness as at El Oaiyarah.
Upper Fars.
A thick series of reddish marls, frequently containing crystals and veiy thin bands of gypsum,
and red sandstones, within the Hit-Ramadi area, a clearly defined greenish sandstone at the base.
Thin bands of a whitish sandstone and of an impure limestone also occur tlnoughout and, in the
Fallujah-Hillah area, these act as bounding planes to very false bedded red marls containing veins
and lumps of gypsum.
The red sandstones reach their greatest development about the middle of theseiies. 1 he beds
below them have only a small content of gypsum, those above a very high content.
Owing to wavyness of the bedding planes and false bedding true dips can only be obtained over
large distances.
The series appears to be conformable with the beds below.
Recent Deposits.
Gravel .—High level gravel deposits of an old river system are found on the hills in places.
Alluvium .—Recent alluvium of the Euphrates covers much of the country between Fallujah
and Hillah, completely masking all outcrops on the left bank between Sadr Latmyah and A u
Ghuraib Post. Alluvium also obscures much of the structure at Naphata.
Secondary Gypsum.
A very impure, apparently secondary gypsum deposit occurs on the high ground near
Musaiyib, and again at Ramadi and Fallujah. In places this gypsum contains pebbles, and we
have not yet decided whether it is an alluvial deposit, or the resorted top of massive gypsum
outcrops. A third possibility is that it has been brought up by capillary attraction and re-deposned.
Pilgrim (Memoirs of the Geological Survey of India, Vol. XXXIV, Part IV, Geology of the
Persian Gulf The historical term used to describe the body of water between the Arabian Peninsula and Iran. and the adjoining portions of Persia and Arabia, page 159) states that similar deposits
have resulted from the leaching of gypsum out of older rocks and its deposition on the surface o
the ground by the subsequent evaporation of the watei.
(4) ASPHALT, SEEPAGES, SULPHUR, Etc.
Seepages occur in two areas in the Euphrates valley, Hit and Naphata, and in a third area to
the south of Hit which we were unable to examine, Aboujir, Jabhah and Aswasil.
Asphalt bands occur at Hit.
(a) Hit.
{!) Asphalt. —15—20 feet above the base, of the Lower Fars there occurs a band of hard,
black asphalt, mixed with gypsum, about 1-1^ feet thick, oveilying mails and oveilain w a i umei
impregnated bed of gypsum. A second band occurs 15 20 feet highei up.
The lower band is very persistent and is visible in the hillsides from the mam outcrop of the
Lower Fars to the south of Hit, to Ain al Taal, 4 miles to the north of the town on the other side
of the river.
At Ain Marj, 5 miles to the N.-W. of Hit, it was not seen and appears to have thinned out in
this direction.
Altogether this band must have originally existed over a minimum extent of 30 squaie mile
of country.
(2) Seepages .—Many seepages of bitumen exist. The consistency of the bitumen is such that
it is impossible to measure its specific gravity with an hydrometer.
(a) There are two seepages close together, about f mile to the west of the town of Hit,
about 50 yards south of them, a third, which is no longer active, once exis e
Both are situated in round pits 6-7 yards in diameter surrounded by debt is mounds fron
old lime workings. They are full of water impregnated with salt and smelling stro g >
of sulphur. Gas is given off in small quantities and bitumen uses con inua y
surface in lumps and strings. It collects in layers on the surface an is - s
for burning in the lime kilns. The water is led off in channels to pans
evaporated for its salt.
Both these seepages are placed several feet below the lower of the two
and appear to originate in the bitumen saturated limestone at the op
Limestone.

File 1450/1919 ‘Mesopotamia & Kurdistan: Geological Reports on’ [‎134v] (283/522)

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File 1450/1919 ‘Mesopotamia & Kurdistan: Geological Reports on’ [‎134v] (283/522)

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