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Fig. 9 Region VIII karst
landform (Tibet karst by Tony
Waltham)
-Central Tianshan Mountains, and where there are meta-
morphic rocks and interlayered carbonates from Proterozoic
to Early Tertiary period (Wang 1990 ; Gao et al. 2001 ). The
rock sequence is generally more than 1,400 m thick in the
Kunlun mountains area reaching 4,000 m in thickness to
7,000 m thick in the eastern Kunlun Mountains. It also
comprises limestone with clastic rocks over 4,000 m in
thickness in the Baryanhar Mountains, while in the Tianshan
area it consists of clastic sedimentary rocks with carbonates
nearly 10,000 m thick. In the southern region (to the south of
Kunlun mountains), there are several thousand meters thick
Carboniferous-Permian limestone with clastic rocks, and
Upper Triassic- Cretaceous clastic rocks with limestone. In
addition, there is 2,900 m thickness of limestone with oolitic
limestone and dolomite in the western Qilian mountain area.
In this region, there are two basic types of karst land-
forms: one is the karst high mountains composed of Middle-
Upper Devonian limestone, biogenic limestone and dolomite
in the southern Tianshan, and Middle Sinian limestone in
Western Qilian Mountains, with a total area of 3,353 km 2
and average altitudes of 4,000
4,500 m (Tianshan area) to 4,900 m (Qinghai-Xizang Pla-
teau area), and relative height from 400
1,000 m in low
-
mountains to 1,500
2,000 m in high mountains (QTPCSI
1983 ; Gao et al. 2001 ) (Fig. 9 ). No karst geoparks have yet
been established in region VIII.
-
4
Discussion and Conclusions
The geomorphologic regionalization of karst in China, pre-
sented in this paper, provides a systematic and comprehen-
sive classi
cation of karst landform development and
distribution in China, based on geographical and geological
data, and their analysis.
The subdivision of karst in China into eight karst geo-
morphologic regions is based mainly on the differences of
geomorphology and climate. Some sub-regions are recog-
nized based on the difference of regional landform, geo-
logical structure and other indicator criteria. The main
eightfold subdivision presents karst landform regional dis-
tribution features. However, because the karst research is
very unbalanced in the western and the eastern China,
obviously there has been more complete research on karst in
the eastern China. For example, the 1:1,500,000 karst geo-
logical survey is used as the base map in western China,
however, suf
4,500 m and relative height
-
of 1,500
2,500 m; the other is semi-karst mountains com-
posed of Proterozoic to Palaeogene carbonate rocks inter-
layered with clastic rocks or impure and metamorphosed
carbonate rocks. These carbonate rocks are scattered
throughout the region except in the area of Qaidam Basin
and Tanglha mountains as well as Kailash Mountains, with
an total area of 677,626 km 2
-
cient data are available in eastern China, and,
as such, for the latter, sub-regions of karst landform can be
recognized (not discussed here).
and average elevation of
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