Guilin takes its name from the flowering acacia trees that scent the city in autumn.
These awesome formations: the Li Jiang landscape, the karst regions of Yugoslavia, the Yucatan Peninsula, and the Alps, are made of limestone, a rock which is one of the most common on earth and covers nearly a quarter of the surface of china.
Four hundred million years ago, southwestern China was a tropical sea, harboring a vast array of shelled sea life. In the warm ocean that covered the Guangxi region, marine organisms, laid down over millions of years, formed the limestone sediments.
The limestone caves of Dordogne region of France, made by the same process as caves of Guilin 20,000 years ago, served as shelters and galleries from human societies that colonized Europe on the fringes of the last ice age (basis of research by novelist, Jean Auel, for her EARTH CHILDREN series beginning with CLAN OF THE CAVE BEAR)
The amount of carbon in sedimentary rocks is more than 600 times the total carbon content of the planets water, air, and living cells. Its slow accumulation and release is part of the drama of plate tectonics.