'Military Report on South-West Persia, Including the Provinces of Khuzistan (Arabistan), Luristan, and Part of Fars' [‎358] (405/466)

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9 Thick deposits of reddish sandstone, fine-grained and hard, without
fossils, but containing a few thin bands of darker-coloured hard iron-sand
stone, tolerably heavy (=4^ and 4 c of fig. 3).
10. At about li mile from the entrance of the pass these sandstones are
succeeded by enormous beds of slate-coloured bituminous shales and marls
( 4 d, fig. 3), which fill up the entire centre of the valley between Tang-i-Khashow
and the pass of Deh-i-Liz, and afford a rich soil for the forest^" of dwarf oaks
which here abound. The water flowing among these marls is scanty, and
highly impregnated with iron. No traces of fossils were here observed. It
is highly probable that these marls are a prolongation of the beds which
crop out on the north side of Chaounifrom under the Mungerrah section, and
rest upon the curve of the Be-Ab (see fig. 5).
It has been previously mentioned that in the centre of the trough of the
Karkhah (fig. 3) a slight curve of limestone occurs at Pul-i-Tang, "the P3ridge
of the Cleft/' through which the river fluws at a depth of 100 feet. At the
point where the river issues from the gorge, and where the limestone again
dips under the gypsum and marls, upon the right bank, several large blocks
have been from some cause or other torn from their places and overturned,—
perhaps by the force of the stream when very high. The under-sides of
these blocks are composed of layers of scutella (sp. undesc.) with abundant
casts of iurritella pecten, and other shells. The same limestone probably
curves upwards and surmounts the great range of the Kabir-Kuh (fig. 3).
Other sections will be alluded to showing the position of the nummulitic
limestones with regard to the cretaceous equivalents; and it is especially
remarkable that while the former are compact and crystalline, and contain
nummidites and allied forms of foraminifera in abundance, the latter are
composed of fawn-coloured fissile layers, which are softer, though sometimes
indurated, or of rotten, blue, bituminous shales.
Although the beds of the two formations are conformable to each other,
the characteristic fossils of each never appear together in any intermediate
bed. Ammonites only exist in the fawn-coloured layers of limestone and in
the blue shales; but, as soon as these rocks cease and the crystalline limestones
succeed in ascending order, the fossil forms are perfectly distinct. How these
changes have occurred it is exceedingly difficult to explain ; but certain it is
that such is the fact, and that the crystalline is perfectly conformable to the
fissile limestone.
Altered nummulitic limestone, —To the eastward of the deposits thus
far described, and extending from Persepolis to near Mount Ararat, are great
mountains of highly crystalline, dark-blue, and foetid limestone, in close pro
ximity to the grand central axis of igneous origin, which causes the paral
lelism of all the exterior ranges. The crystalline and contorted structure of
these deposits is necessarily to be ascribed to the protrusion or concealed
presence of the igneous mass. When stratification is apparent, it is so con
torted and crushed that there is no possibility of tracing the beds. Generally
all traces of stratification are absent, and the mass is of homogeneous texture
throughout. The colour of the stone is usually dark blue, but it sometimes
varies to light grey, and even in some cases to white. It is compact, rough
to the touch, excessively hard and heavy, with a saccharoidal fracture, and a
bituminous or foetid odour when struck with the hammer. It is a good
building stone, assumes a fine polish, and is equally suitable for internal or
external decoration, as is well shown at the deserted and ruined palaces of
Persepolis and Susa.
{See foot note, page 352.