Alps-Himalaya System

The Alpide belt or Alpine-Himalayan orogenic belt is a seismic belt and orogenic belt that includes an array of mountain ranges extending along the southern margin of Eurasia, stretching from Java to Sumatra through the Himalayas, the Mediterranean, and out into the Atlantic. It includes the Alps, the Carpathians, the Pyrenees, the mountains of Anatolia and Iran, the Hindu Kush, and the mountains of Southeast Asia. It is the second most seismically active region in the world, after the circum-Pacific belt (the Ring of Fire), with 17% of the world's largest earthquakes.

The Alpide belt is being created by ongoing plate tectonics such as the Alpine orogeny. The belt is the result of Mesozoic to Cenozoic to recent closure of the Tethys Ocean and process of collision between the northward-moving African, Arabian and Indian plates with the Eurasian plate.

Indonesia lies between the Pacific Ring of Fire along the northeastern islands adjacent to and including New Guinea and the Alpide belt along the south and west from Sumatra, Java and the Lesser Sunda Islands (Bali, Flores, and Timor). The 2004 Indian Ocean earthquake just off the coast of Sumatra was located within the Alpide belt.