The ancient river Zarafshan in the translation from the Persian language means "a river carrying gold." Hence the name of the valley, the sands of which are impregnated with gold. According to the physico-geographical location, the Zarafshan Valley includes the central part of Uzbekistan, where it is surrounded from the north by the Nurata Mountains, sandy deserts of the Sung-Dudley, in the west and north-west by the deserts of the Karakum and Kyzylkum.
In the territory of Uzbekistan, the Zarafshan valley is sometimes widening and sometimes narrowing. In the expanded part are Samarkand, Bukhara and Karakul oases, in the narrowed - Khazar and Kara-Kul corridors.
Samarkand oasis is located in the eponymous hollow. The widest area of the Samarkand depression is 70-80 km, length 220 km, elevation 350-905 m above sea level. In the west the hollow is separated from the Bukhara oasis through the Khazar corridor.
The Zarafshan valley expands to the west and forms the Bukhara oasis. From the north and west it is framed by the Kyzylkum desert, and in the southwest the Karakul plateau separates it from the Karakul oasis.
Zarafshan Valley is located on the trough of the Turan plate and is filled with Neogene and Quaternary sediments. There was a sea up to the Neogene. As a result of the newest tectonics, land was formed. Later, as a result of the deepening of the riverbed of the Zarafshan River, river terraces formed. The mountains surrounding the valley were formed in the Paleozoic era as a result of Hercynian folding in the coal-stone period.
The mountains of Aktau are located in the north of the Zarafshan valley. North-of-Aktau is the Nurata-Kuytash basin, whose average elevation is 500-600 m. In the north it is located at the Nuratinsky хре-бет with a height of 1,500 m. The highest point is the peak of Khayatbashi (2,169 m).
One of the most important assets of the Zarafshan physical and geographical area is natural gas. It is mined in Jarkaka, Karaulbazar and other places in the vicinity of the Bukhara and Karakul oases.
Climate and water
Climate. Zarafshan physico-geographical region is located on subtropical latitudes. There are many cloudless sunny days, so 1 cm2 of the earth's surface per year accounts for 150 kcal of radiation. The duration of sunshine reaches 3,000 hours per year, so the summer in the Zarafshan Valley is hot and dry, and the winter is relatively warm.
In the north-eastern part of the Zarafshan valley framed by mountains, the effect of cold air masses coming from the north and northeast is insignificant. Conversely, in the western part of the valley, open to free penetration, much cooler. Thus, in the east of the valley (in Samarkand), the average temperature is -0.5 ° C, in the west (in Shafirkan) - 1.5 ° C. And on the contrary, in the summer in the western part of the valley it is hotter, the average July temperature in Shafirka is + 29.1 ° C, in the eastern part - Samarkand + 26 ° C. In the mountains surrounding the valley, the winter is relatively cold, the summer is cool
In the Zarafshan physico-geographical region, the precipitation is distributed unevenly throughout the territory and falls mainly in spring and winter. In the west, 114-177 mm fall, in the east - 300-350 mm, in the mountains (Amankutane) - 881 mm.
Summer here is hot, dry and long, evaporation is several times greater than the amount of precipitation. As a result, the soil is strongly drained, saline, and the plants dry out. Only in the mountains sometimes in the summer months precipitation may fall out.
Spring comes early. During this period, 43-50% of annual precipitation falls. Closer to the mountains the amount of precipitation increases. From torrential rains, the formation of mudflows is possible.
In the autumn it's still warm. The first autumn frosts are observed in the western part of the district on October 22-25, in the east - on October 28 and in the mountainous - on September 30.
Winter is usually short, mild, with moderate frosts. Precipitation is greater than in autumn; For the winter months, there are 35-40% of annual precipitation. Precipitation mostly falls in the form of snow. The thickness of the snow cover in the area is not the same. In the western part of the valley, snow does not melt until 7 days and reaches 6-7 cm, in eastern snow it does not melt for 15-20 days and reaches 8-13 cm, while in the mountain part the snow cover lasts almost a month and its thickness reaches 25 -30 cm.
Water. The main water source of the region is the Zarafshan River. It originates from the Zarafshan glacier on the territory of Tajikistan. Only the middle and lower reaches of the river belong to Uzbekistan. The river flows towards the west and, not reaching the Amu Darya, is lost in the sands.
The name "Kyzylkum" in translation from Turkic means "red sands". The reddish coloration here is of sand, formed by weathering and waving the bedrock. In the northern, near Syr-Darya strip, which is like the Central Karakum, an ancient alluvial plain with accumulations of sand that resulted from the transfer of alluvium, the sands are grayish-yellowish. The surface of the desert has a gentle general slope from the south-east to north-west, to the coast of the Aral Sea.
Kyzylkum - one of the greatest deserts of Eurasia - extends from the coast of the Aral Sea in the north, to a relatively narrow fertile oasis belt near the Zarafshan River in the south. This vast area of 300,000 square kilometers from the east and west is bounded by the great Central Asian rivers Syrdarya and Amudarya. The Kyzylkums occupy most of the Navoi region.
The Kyzyl-Kum - many-sided. Here the boundless expanses of loose sands with the barkhans with bush of saxaul and camel thorn are replaced by clay plains with hills. There are here places with smooth and even, like parquet takyrs, hard, as concrete. There are rocky, though low mountains, mineral springs, saxaul groves, outcrops of indigenous rocks of ages of one billion or more years. There are present and former lakes. The hottest and driest place in Uzbekistan is in Kyzylkum. Annual precipitation does not reach 70 mm here. In the summer, the Kyzyl Kum receive so much sunshine that they are red-hot beyond all limits. It is no accident that this desert is called the Red Sands.