The world's distribution of earthquakes coincide very closely with that of volcanoes. Regions of greatest Seismicity are Circum-Pacific areas, with the epicentres and the most frequent occurrence along the 'Pacific Ring of Fire'. It is said that as many as 70 % of earthquakes occur in the Circum-Pacific belt. Another 20% of earthquakes take place in the Mediterranean-Himalayas belt including Asia Minor, the Himalayas and parts of north-west China. Elsewhere, the earth's crust is relatively stable and is less prone to earthquake though nowhere can be said to be immune to earth tremors.