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Chapter 07
Ancient Tibet - History and Culture
Main Central Fault, thrusting movements pushed older rock layers up over younger layers. This great northward pressure contracted the plateau, thickening its crust, and exerted force on all the older mountains, creating more folding and thrusting these ranges up even higher. Gangs-ti-se greatly increased at this time. Volcanoes began erupting north of the collision zone, gradually forming farther and farther north, until they arose along the Kun-lun mountains. This series of volcanoes, which are now extinct, can be seen south of Muztagh Ata peak in the Kun-luns and south of Margai Caka salt lake in Byang-thang. Tectonic Plates of The World
Crnamam
US EURASIAN PLATE
CU
Europe
Tibet
China
NORTH AMERICAN
PLATE
India
AFRICAN
V
to 3o
PACIFIC PLATE
SOUTH
PLATE
AMERICAN
PLATE
INDO-AUSTRALIAN PLATE
ANTARCTIC PLATE
DIFFERENT TYPES OF PLATE BOUNDARIES ACCORDING TO PLATE TECTONIC THEORY
new crust forming between ocean plates
ocean crust colliding with continental crust
continental crust colliding with continental crust
- continental rift
fractures of various kinds
u
ocean crust colliding with ocean crust or continental shelf
Recent geological discoveries indicate that the surface of the earth is divided into a number of separate plates that change positions, floating on top of the deeper deformable layers of the planet. The movements of these plates are thought to have created the mountains and oceans, while constantly shifting the position of the land. The modern arrangement of land is less than 100 million years old and is continuing to change as the plates move at the rate of two to eight centimeters per year (two to eight meters per century).
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Ancient Tibet
