Lop Desert

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1 Sand storms
2 See also
3 References
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Satellite picture of the Desert of Lop with the Basin of the formerly sea Lop Nur. In the left Kuruktagh, in the right Astintagh.

The Desert of Lop or Lop Nur or Lop Nor, is a desert which extends from Korla eastwards along the foot of the Kuruktagh to the formerly terminal basin of the Tarim, in the Xinjiang Uygur Autonomous Region of China. It is an almost perfectly horizontal expanse, for, while the Lake Bosten in the northwest lies at an altitude of 1.030 m -1.040 m, the Lop Nur in the southeast is only 250 m lower. The characteristic features of this almost dead-level but slightly undulating region are:

broad, unbroken expanses of clay intermingled with sand, the clay (shor) being indurated and saliferous; and often arranged in terraces;
hard, level, clay expanses, more or less thickly sprinkled with fine gravel (say), the clay being mostly of a yellow or yellow-grey color;
benches, flattened ridges and tabular masses of consolidated clay (yardangs), arranged in distinctly defined laminae, three stories being sometimes superimposed one upon the other, and their vertical faces being abraded, and often undercut, by the wind, while the formations themselves are separated by parallel gullies or wind. Furrows, 6 to 20 feet deep, all sculptured in the direction of the prevailing wind, that is, from northeast to southwest; and
the absence of drift-sand and sand dunes, except in the south, towards the outlying foothills of the Astin-tagh.

[edit] Sand storms

Perhaps the most striking characteristic, after the yardangs or clay terraces, is the fact that the whole of this region is not only swept bare of sand by the terrific sand storms (burãns) of the spring months, but, the particles of sand with which the wind is laden act like a sand-blast. The actual substantive materials of the desert itself are abraded, filed, eroded and carried bodily away into the network of lakes in which the Tarim loses itself. They also blow across the lower, constantly shifting watercourses of the Tarim river, and deposit on or amongst the gigantic dunes that choke the eastern end of the desert of Taklamakan. Numerous indications, such as salt-stained depressions of a lacustrine appearance; traces of former lacustrine shorelines, more or less parallel and concentric; the presence in places of vast quantities of fresh water mollusc shells (species of Linnaea and Planorbis); the existence of belts of dead poplars; patches of dead tamarisks and extensive beds of withered reeds. All of these are always on top of the jardangs, never in the wind etched furrows, together with a few scrubby poplars and Eksea gnus, still struggling hard not to die. The presence of ripple marks of aqueous origin on the leeward sides of the clay terraces and in other wind-sheltered situations, all testify to the former existence in this region of more or less extensive freshwater lakes, now of course completely desiccated. During the prevalence of the spring, storms in the atmosphere that overhang the immediate surface of the desert are so heavily charged with dust as to be a veritable pall of desolation. Except for the wild camel which frequents the reed oases on the north edge of the desert, animal life is even less abundant than in the Ghashiun-Gobi. The same is true as regards the vegetation.