‘Military report on south-west Persia, including the provinces of Khúzistán (Arabistan), Luristán and part of Fars.’ [‎200v] (405/470)

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descent of several hundred feet, this limestone is overlaid by fissile blue shales
and indurated marl ( 4 J) having the same dip.
The Merwan Pass is next crossed, in the ascent ot which the limestone
beds ( 4 a) occur in ascending order. _
The cream-coloured limestone, containing marks ot fitci, appears to pass
imperceptibly into the overlying nummulitic rocks ( 3 ), which are, as usual,
hio-hly crystalline, and contain nummulites and pectens.
& The summit of the pass consists of this crystalline limestone, and the
descent eastward to the Ab-i-Bazuft is over the same beds, dipping at an
anode of 70°. On the right bank of this river, which Hows through a wild,
confined, and deep gorge, the limestone becomes less crystalline and more
marly, and an inconsiderable bed contains shark s teeth, nummulites, pectens,
&c., similar to those at Pul-i-Tang. .
This marly bed is soon concealed by a powerful series ot the gypsiterous
rocks, which rise from the Ab-i-Bazuft into high cliffs of gypsum and of red
and fawn-coloured earths, mingled with gravel conglomerate and breccia, in a
confused mass, as if the bed had been shot off the side of Merwari during
its sudden elevation. Masses of gravel -conglomerate lie in the bed of the
stream, and high up on the slopes of the mountain through which the Ab-i-
Bazuft flows, t , .
In this section, then, we have between the sphaerulitic limestone and the
nummulitic rocks a series of blue marls and cream-coloured limestones, the
latter passing imperceptibly into the nummulitic rocks.
Unfortunately these marls and limestones are without characteristic fos
sils; but, as I have elsewhere remarked, as soon as the nummulitic rock assumes
its usual crystalline appearance, the peculiar and very characteristic remains
of that series show themselves in remarkable abundance. If we had only this
section, we should be at a loss whether to consider the marls and cream-
coloured limestone as belonging to the cretaceous or to the nummulitic rocks.
Fortunately, we have elsewhere sufficient evidence of organic remains to prove
that they must be undoubtedly classed as cretaceous. It is very remarkable,
however, that in no instance have I met with any admixture of chalk and
nummulitic fossils, although a gradual transition certainly takes place in litho
logical character.
At Khoramabad the lofty and imposing range of the Yaftah-Kuh rises
abruptly from the plain (fig. 3), and is, in my opinion, of the cretaceous
age. It consists of light grey or bluish cherty limestone, with alterna
ting and continuous layers of variously-coloured flint, chiefly black. Hie
limestone is exceedingly hard and compact, breaks with a conchoidal fracture,
and emits a highly bituminous odour when struck. It is unfossiliferous.
A saddle is formed by the curvature of the beds, the continuity of which
is, however, broken at the summit. At the centre a good deal of zigzag con
tortion is perceptible in the lower beds ; but this gradually becomes less, and
eventually dies out in the upper beds. The dip on the south is at an angle of
37° and on the north 25° [seepage 217).
On quitting Khoramabad in a north-west direction, the stratification in
the valley of the river which waters the town is concealed under loose gravel;
but, about half-way to Rabat, a considerable range of gravel conglomerate is *
* Unfortunately my specimens from these localities are lost.
t A few miles north-east of this stream (but before reaching the left hank of the Kuran at
Dupulan) I procured from a hard rock of the blue marly limestone a gigantic species of
alveolina, 3 inches in length.