Gao Jun is located in the Himalayas and the Karakorum mountains, the geographical environment in arid, closed zhang, why Tibet will become a source of civilization?

• 地处高峻的喜马拉雅山和喀喇昆仑山之间、地理环境干旱、封闭的象雄，为什么会成为西藏文明的渊源？