'IRAQ AND THE PERSIAN GULF' [‎68v] (141/862)

88 GEOLOGY AND DESCRIPTION OF THE LAND
Darband-i-Basira (p. 98; fig. 25). It also collects much drainage
from the south-western flanks of these ranges and flows south past
the north-western ends of the Aj Dagh and Baski Zanur Dagh. The
country is broken up by ravines, but is otherwise open until the river
approaches the Jabal Tasak which deflects it westwards. Here it
collects other streams and winds between low walls of conglomerate,
gypsum, and sandstone through the range. Below the defile its bed
becomes a shingle flood-plain nearly 1,000 yards wide and it breaks
up into many channels. Like the Aq Su, the Tauq Chai is liable to
dangerous rises after rain and then becomes unfordable, but at no
season is it less than 3 feet deep or 15 feet wide. The large village of
Tauq is on the right bank about 4 miles from the mouth of the defile;
its cultivated fields are irrigated by water from the river raised by
water-wheels. Lower down across the plain its bed is very similar to
that of the Aq Su, until near the Jabal Hamrin, 25 miles from Tauq,
it is joined by the Zaghaitun Chai and flows south-eastwards, deeply
cut into foothills.
The Qadha Chai rises from numerous springs in the plateau north
west of the grassy undulating Chemchemal plain, which forms a
plateau watershed between this river and the Tauq Chai. Chem
chemal is a prosperous village around which a considerable amount of
barley is grown, but the plain is mostly used for pasture. The Qadha
head-streams have cut their beds into the soft soil and are now deeply
incised. The river flows west-south-west until it meets the low Kani
Domlan fold; this rises only 250 feet above the plain, but is a marked
feature north-westwards to the Little Zab and is continued beyond
that river by the more prominent Avana Dagh. This range of the
Kani Domlan hills contains a long narrow outcrop of Pars rocks.
The main mass is of brown and bluish sandstones with thick bands of
blue clay, and limestone and gypseous exposures. It is bare of vegeta
tion, but beneath the rocks is the rich oilfield of Kirkuk, from which
crude oil is pumped 650 miles across the Jazira and the Syrian desert
to Haifa and Tripoli on the Mediterranean coast.
The Qadha winds through the range to the large town of Kirkuk
standing on both banks. The river here only holds water during
the winter or after rain (photo. 29); it has a pebble-covered bed from
160 to 220 yards wide, but since it carries none of the run-off of the
main mountain barrier to the north its spates are neither dangerous
nor violent. Below Kirkuk it branches into several channels and flows
south-south-west to near Taza Khurmatli. Lower down new springs
make it perennial and it feeds a marshy tract which is drained south