'Military Report on South-West Persia, Including the Provinces of Khuzistan (Arabistan), Luristan, and Part of Fars' [‎344] (391/466)

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APPENDIX C.
GEOLOGY OF SOUTH-WEST PERSIA.
Extracts from a 'paper on the Geology of the TurJco-Persian Frontier and of the
districts adjoining, hy W. K. Loft us, Esq., p. as., June 1864,
N.B.—This account should be read with Eoad Eeports No. 1,3, Zia), 4. Adupti^y A
and Part II —" Details of the hills of Luristan." '
I£ a traveller approach the dominions of the Shah from the Persian Gulf The historical term used to describe the body of water between the Arabian Peninsula and Iran.
or from Lower Mesopotamia,—that is, between the parallels of latitude of
Shiraz and Suleimania (29 w 36' and 35° 16' N.),—he must cross the vast
range of the ancient Zagros, and invariably meet with the greater portion of
the section as exhibited in fig. 1. Further northwards, however, the igneous
eruptions alter and contort the sedimentary rocks in such a manner as to
render their recognition no very easy task. I therefore deem it advisable to
describe, in the first place, the least complicated and best developed sections
in the south, extending as far northward as the Ab-i-Shirwan (lat. 35° 8' N.);
and, in the second place, to describe certain sections in the north, which
throw light on the age of the disturbing forces, and present some interesting
phenomena connected with the deposits of travertin.
PART I.
Although contrary to the usual course, I propose describing the various
formations in descending order, because they so present themselves to the
traveller going eastward, and because this plan is more likely to be serviceable
to such European travellers as may feel desirous of adding to our scanty
knowledge of the geology of those little visited regions.
I.—Recent Deposits.
1. Alluvium* This term has usually, with regard to the Mesopotamian
plains, been applied to the soil composing the basins of all the great rivers
falling into the Persian Gulf The historical term used to describe the body of water between the Arabian Peninsula and Iran. .
The alluvium may be clearly divided into—(A) fluviatile and (B) marine.
(A) The fluviatile alluvium, now in process of deposition,^! is limited to ii0 J
the banks of the rivers, with the adjoining marshes and canals. It consists ^
of a stiff blue, or fine arenaceous grey clay, and fine sand or gravel. These ^
deposits are dried and cracked in every direction by the intense heat of the ^
sun, and are on this account exceedingly difficult for a horseman to traverse.
They afford a rich soil for the cultivation of maize, rice, w^ater^melons cucnm-
bers, and the ordinary vegetables of the Arabs; and they frequently contain ^
imbedded shells of extinct species of the genera Cyrena, Unio, Melanopsis, S
Helix, &c. ' y ; i|of
(B) The marine beds of the alluvium are much more extensive than the
fluviatile, and consist of dark-grey or reddish-yellow loose sand and sandy J W
marls. These are usually seen in the desert at some distance from the rivers;
and, where not otherwise distinguishable from the beds of the underlying ^
rocks, are to be recognized by the growth of saline plants, and by dark wet
patches produced by the presence of chloride of sodium. They are sometimes Nil
accompanied by fossils.
In the neighbourhood of Muhammerah, Sablah on the Karun, and
Busrah are the following shells, identical with species now living"at the mouth
of the Persian Gulf The historical term used to describe the body of water between the Arabian Peninsula and Iran. , so far at least as they h av e been compared with a small