El Chichón volcano is located within the Chiapas region of South-East México at an elevation of ~1150 m (GVP, 2007). It is a remote andesitic stratovolcano  in the Modern Chiapanecan Volcanic Arc (MCVA) with an ago of ~0.2 Ma years. El Chichón is at the most North-Western extent of the MCVA which is thought to be ~3 Ma years old (Manea and Manea, 2008; Simkin and Siebert, 1994). The closest volcano, Vulcan de San Martin, is 200 km to the North-West. 

El Chichón has been sporadically active during the recent Holocene period and in the geological record there are a minimum of 12 eruptions detected during the past ~8000 years; none of which are thought to have been larger than the 1982 eruption (Tilling et al. 1984; Macias et al. 2008). Historically the eruptions seen at El Chichón are a combination of lava dome and phreatomagmatic eruptions; the main hazards from eruptions are ashfall and column collapse causing PDCs (Pyroclastic Density Currents) (Tilling et al. 1984; GVP, 2007; Macias et al. 2008). The eruption which occurred ~600 years ago  is thought to have played a part in the downfall of the Mayan civilisation! 

The modern day eruption started suddenly on the 28th March 1982 at 23:22 local time with a plinian eruption column reaching to ~20 km (Sigurdsson et al. 1984; GVP, 2007). A max column height of ~27 km was recorded (Macias et al. 2008). This first major episode lasted until 0600 on the following morning and the population within 5 km of the volcano began to evacuate due to the high amount of ash falling as far as ~20 km away. During the following days there were a few minor phreatic eruptions recorded on the 30th and 31stof March (Sigurdsson et al. 1984; GVP, 2007).