The climate in the mountains in the north and
western parts of the basin is cold and wet. Once
summer arrives, vast amounts of snowmelt flow
down in streams, and most of the water seep into
the coarse gravel as the streams flow across an
8–10km wide Gobi belt with a relatively steep
slope. Both the surface runoff and groundwater
flow towards the lower basin areas. This provides
rich water sources for the lower basins that are
mainly covered with fine sand and loess soil.
With an altitude of about 800m and located
at the northeastern edge of the basin, the Flaming
Mountain intercepts part of the groundwater
recharged into the gravel layers of the Gobi belt
and raises the groundwater table. As a result,
many springs flow out into the northern foot of
the mountain, then run through hills and valleys,
and ultimately seep into the alluvial fans. The
qanat systems in the Turpan Basin generally tap
groundwater from the northern and northeastern
alluvial fans and transfer it to the lower basin
areas towards the Aiding Lake.
Figure 1: Satellite photo shows the steep
mountain range and the flat plain of the Turpan
region
The Turpan Basin has special hydrogeological
features favourable for the building of large
qanat systems. The basin has high temperatures
and scarce precipitation, and is extremely dry.
With a maximum summer temperature of more
than 40°C, it earned its name “Land of Fire”.
Components and Construction
A qanat system generally consists of four
components:
a. vertical wells/shafts,
b. tunnels for conveying water
c. open channels, and
d. collection ponds.
Figure 2: Schematic cross-section of karez well system
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