A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Engineering and Technology

Thesis (M.Eng.) - Asian Institute of Technology, 1993

Mount Pinatubo volcano, an andesitic-dacitic dome 100 km NW of Manila, renewed its activity by a phreatic eruption on 2 April 1991. The escalation of the different precursory phenomena manifested by the volcano were monitored by the Filipino and American Scientists. An increase in volcanic earthquake of 1500 events/day were manifested on June 7 combined with the measurement of SO2 emission of 13,361 tonnes/day on June 10, culminated in a series of Plinian-type eruptions on June 12-15, 1991. The estimated pyroclastic flow deposits are about 7-11 km , where these covered the upper slopes of the volcano. The monitoring techniques used were reviewed and studied. The eruptions produced mainly the three direct volcanic hazards namely; Pyroclastic flows, ashfalls and lahars. These were evaluated for their consequences on the landuse pattern of the area surrounding the volcano. A GIS package, the ARC-INFO Software was utilized in generating the landuse map, where the different volcanic hazards where overlayed on the landuse map. The pyroclastic deposits covered about 170 km2 of various landuses. The newly emplaced materials become the main supply for the lahars that occurred during the onset of rainy season.