Little is said about volcanism in Vietnam. A recent article by Professor Nguyen Hoang, from the Japan National Science and Technology Institute, reveals that the island of Ly Son, located in the Quang Ngai province in central Vietnam, has experienced volcanic activity on two major periods, ranging from deep to shallow marine activity and aerian activity. Ly Son actually consists of three islands: Ly Son (Đảo lớn) , the largest and two smaller islands, Bo Bai (Đảo Be) and Hon Mu Cu.
The first period of activity was in 11-10 Ma, the second is dated about 1 Ma, and coincides with the activity to Ba Binh An and Lang Chau. Each eruption of lava formed of layers of different thicknesses, still visible today. The volcanic field occupies 70% of the surface of the island.
The relics of this volcanic activity are valued tourists landscapes : Cau Cave, Hang Pagoda, Duc temple, and a natural lava arch.
Hang Pagoda and the Duc temple are built inside caves formed by erosion in the cliffs. Hang Pagoda is located in a cave in the mountains Thoi Loi, the highest of the five peaks of the island; it measures 20 meters wide, 24 meters long and three meters high.
A geological park will enhance its recent status of natural museum of volcanic activity.
The Ly Son Island is renowned for the production of garlic with a typical flavor, because of its culture on volcanic soil. This production of garlic and onion occupies one third of the island, which is the nickname of "the kingdom of garlic".
Source :
Vietnam breaking news - 10 million years old volcano sedimentary cliffs on Ly Son island - link