and Herat) is the formation of those immensely deep gorges
and defiles which are locally known as daras. One of these,
in the Astarab, to the south-east of Maimana, is but 30 yds.
wide, and is enclosed between perpendicular limestone cliffs
1500 ft. high. C. L. Griesbach considers that the general
outline of the land configuration has remained much the same
since Pliocene times, and that the force which brought about
the wrinkling of the older deposits still continues to add
fold on fold. The highlands which shut off the Turkestan
provinces from Southern Afghanistan have afforded the best
opportunities for geological investigation, and as might
be expected from their geographical position, the general
result of the examination of exposed sections leads to
the identification of geoloeical affinity with Himalayan,
Indian and Persian regions. The general configuration
of the Turkestan highlands has been already indicated.
Against the last great fold which terminates this mountain
area northwards are ranged the Tertiaries and recent
deposits. North of Maimana they form low undulating loess
hills, in which most of the Band-i-Turkestan drainage is
lost. This wide-spreading loess area, formed partly of
wind-blown sand and partly of detritus from the mountains, is
known as Chul, and merges into the great plains south of the
Oxus river, a great part of which is covered with modern aerial
deposits. Beneath this Chul formation the older beds of
the outer and Turkestan ranges dip and pass to an irregular
outcrop near the banks of the Oxus. Between the Oxus and the
hills there has already been formed a rise or flexure in the
ground, which extends more or less parallel to the northern
edge of the hills, and, shuttinr in the cultivated area of the
plains, arrests all tributaries seeking to effect a junction
with the Oxus from the south, and leads to the formation
of marshes and swamps. This appears to be the beginning of
a new anticlinal which has altered the levels of the Balkh
plain, and is indicative of those elevating processes which
may have been effective within historic times in changing
the climate and the agricultural prospects of this part
of Central Asia. The Oxus itself is steadily encroaching
on its right banks and depositing detritus on the left.
No fresh discoveries of minerals likely to be of hich
economic value to Afghanistan have been made of late
years. Such as are known and worked at present have been
worked from very ancient times, and their capacity is not
likely to develop greatly under the Kabul government. The
most important feature in this connexion which was noted
by the geologist of the Russo-Afghan Commission is the
existence of vast coal beds in northern Afghanistan. In 1903
some coal mines were discovered in the Jagdalak districts.
There are no glaciers now to be found in Afghan Turkestan; but
evidences of their recent existence are abundant. The great
boulder bed terraces in some of the valleys of the northern
slopes of the Ferozkhoi plateau are probably of glacial
origin. In the mountains west of Kabul glaciers have
retired, leaving the moraines perfectly undisturbed. They
are probably contemporary with the older alluvia. (T. H. H.*)
Rocks.
The oldest rocks which have yet been identified 1 in Afghanistan
occur along the axis of the main watershed, and have been
referred to the Carboniferous. At Robat-i-Pai near Herat, for
example, there is a dark Productus limestone which seems
to be identical with the Productus limestone of the Central
Himalayas. These beds are conformably succeeded, along the
Central Asian watershed, by a continuous series of strata
which apparently represent the Permian, Trias and Jurassic of
Europe. They consist of marine beds alternating with
freshwater and littoral deposits, together with plant beds
and coal-scarns of considerable thickness. The lowest beds
of this series, which from their position may belong either
to the Permian or to the upper part of the Carboniferous,
have yielded no recognizable fossils; but they include a
conglomerate which closely resembles the boulder bed near the
base of the Talchir series in India. The Upper Trias has been
definitely identified by the occurrence of Halobia and other
fossils; while in the higher beds of the series marine forms
belonging to the middle and upper Jurassic have been found.
The plant beds occur at several horizons, and among the
remains which have been found in them are several forms
which occur also in the Gondwana beds of India. There can
be no doubt that the series as a whole is the equivalent
of the Gondwana system, and when the country has been
more closely examined the association of marine fossils
with Gondwana plants will be of the greatest value in
determining the precise homotaxis of the Indian deposits.
The Jurassic beds are followed, generally with perfect
conformity, by the Cretaceous, which covers a large part of
Afghan Turkestan and probably forms the greater part of the
ranges which run south and south-west from the principal
watershed. The lowest beds consist of red grits which contain
Neocomian fossils, while the middle and upper Cretaceous
consist chiefly of limestone and chalk. The entire system
may be represented in the west, but in the Herat province
and in Afghan Turkestan the middle Cretaceous seems to be
absent, and it is probable that, as in other regions, the
upper Cretaceous covers a much wider area than the lower
beds. Tertiary and recent deposits are widely spread, filling
most of the valleys and covering the plains of the Helmund.
Eocene beds have not yet been proved to exist; but this is
probably owing to the imperfect knowledge of the country, for
the formation is known in Persia, Baluchistan and the Suliman
Hills. The lower part of the Miocene is marine in Herat
and Afghan Turkestan; but the upper Miocene is usually of
freshwater or estuarine origin. in Afghanistan, as in other
regions near the great Eurasian system of folds, the Miocene
includes extensive deposits of gypsum and salt. It was during
this period that the forces which finally raised the country
above the level of the sea began to take effect. The Pliocene
consists entirely of freshwater and terrestrial deposits, which
were probably laid down at the foot of the rising hills and
on the floors of the intervening valleys. As the elevation
continued, they were sometimes involved in the folding to
which the mountains owe their origin. During this period the
gradual desiccation of the country continued, and wind-blown
deposits, such as the loess, began to make their appearance.
Although volcanic cones are known both in Persia and in
Baluchistan, none have yet been described in Afghanistan
itself. There is, however, ample evidence that at several
distinct geological periods the region has been the seat
of great volcanic activity. According to C. L. Griesbach,
basic volcanic rocks are interbedded with the lowest part of
the plant-bearing series, and enormous outbursts took place
during the Neocomian period. But the most important igneous
masses are the great intrusions of syenitic granite and of
basic rock which penetrate the Cretaceous beds. These are
probably of Eocene or of late Cretaceous age. (P. LA.)
Omitting the group of northern routes to India from Central
Asia, which pass between Kashmir and Afghanistan through
the defiles of Chitral and of the Indus (see HINDU KUSH),
the highways of Afghanistan may be classed under two heads:
(1) Foreign trade routes, and (2) Internal communications.
The most important commercially are those which connect the Oxus
regions and the Central Asian khanates with Kabul, and those
which lead from Kabul, Ghazni and Kandahar to the plains of India.
Kabul is linked with Afghan Turkestan and Badakshan by three
main lines of communication across the Koh-i-Baba and the Hindu
Kush. One of these routes follows the Balkh river to its
head from Tahshkurghan, and then, preserving a high general
level of 8600 to 9000 ft., it passes over the water-divides
separating the upper tributaries of the Kunduz river,
and drops into the valley formed by another tributary at
Bamian. From Bamian it passes over the central mountain chain
to Kabul either by the well-known Dasses of Irak (marking
the water-divide of the Koh-i-Baba) and of Unai (marking the
summit of the Sanglakh, a branch of the Hindu Kush), or else,
turning eastwards, it crosses into the Ghorband valley by the
Shibar, a pass which is considerably lower than the Irak and
is very seldom snowbound. From the foot of the Unai pass it
follows the Kabul river, and from the foot of the Shibar it
follows the circuitous route which is offered by the drainage
of the Ghorband valley to Charikar, and thence southwards to
Kabul. The main points on this route are Haibak, Bajgah and
Bamian. It is full of awkward grades and minor passes, but
it does not maintain a high level generally, no pass (if the
Shibar route be adopted) much exceeding 10,000 ft. That this
has for centuries been regarded as the main route northward
from Kabul, the Buddhist relics of Bamian and Haibak bear
silent witness; but it may be doubted whether Abdur Rahman's
talent for roadmaking has not opened out better alternative
lines. One of his roads connects Haibak with the Ghorband
valley by the Chahardar pass across the Hindu Kush. The pass
is high (nearly 14,000 ft.), but the road is excellently well
laid out, and the route, which, south of Haibak, traverses a
corner of the Ghori and Baghlan districts of Badakshan, is more
direct. A third route also passes through Badakshan, and
connects Kunduz with Charikar by the Khawak pass and Panjshir
river. The latter joins the Ghorband close to Charikar. The
Khawak (11,600 ft.) is not a high pass; the grades are easy
and the snowfall usually light. This high road is stated (on
Afghan authority) to be kept open for khafila traffic all the
year round by the employment of forced labour for clearing
snow. It is a recently developed route and one of great
imoortance to Kabul, both strategically and commercially.
Routes that pass between the mountain barriers of the frontier
between Peshawar and the Gomal occur at intervals along the
western border, and in the northern section of the Indian
frontier they are all well marked. The Khyber, Kurram and
Tochi are the best known, inasmuch as all these lines of
advance into Afghanistan are held by British troops or Indian
levies. But the Bara valley route into the heart of the Afridi
Tirah is not to be altogether overlooked, although it is not
a trade route of any importance. Between Kabul and Jalalabad
there are two roads, one by the Uataband pass, and the other
and more difficult by the Khurd-Kabul and Iagdalak passes, the
latter being the scene of the massacre of a British brigade in
1842. Between Jalalabad and Peshawar is the Khyber pass
(q.v..) The Khyber was not in ancient times the main route
of advance from Kabul to Peshawar. From Kabul the old route
followed the Kabul river through the valley of Laghman (or
Lamghan, as the Afghans call it) over a gentle water-parting
into the Kunar valley, leaving Ningrahar and Jalalabad to the
south. From the Kunar it crossed into Bajour by one of
several open and comparatively easy passes, and from Bajour
descended into India either by the Malakand or some other
contiguous frontier gateway to the plains of Peshawar. 8600
and 10,800 ft. respectively) across the southern extensions of
the Safed Koh range, and has never been a great trade route,
however suitable as an alternative military line of advance.
