old karst的意思|示意

The modem karst formation started in the old Tertiary Period, and matured in the Quatemary Period.

现代岩溶的形成开始于老第三纪，成熟于第四纪。

Guilin is an old city with 2100 years history. Its rich history and Karst cultural landscape is the important part of Guilin's tourism industry.

桂林以其2100年的丰厚历史底蕴及喀斯特山水文化成为该市旅游资源不可或缺的重要组成部分。