Geohazards pp 13-24 | Cite as

Volunteer Observers Program: a tool for monitoring volcanic and seismic events in the Philippines

  • Perla J. Delos Reyes
Part of the AGID Report Series book series (ARS)


The Philippine Archipelago is one of the most tectonically active and volcanic regions of the world and, as such, frequent occurrences of volcanic eruptions and destructive earthquakes are to be expected. One of the main objectives in the creation of the Philippine Institute of Volcanology and Seismology (PHIVOLCS) was the mitigation of the effects of volcanic eruptions and earthquakes through prediction and prompt warning.

The Philippines lacks the technology and manpower needed for its program on volcanic and earthquake prediction. Therefore PHIVOLCS devised a Volunteer Observer Program to enlist the help of residents in areas likely to be affected by volcanic and seismic events, and to increase its sources of precursory signs such as crater glow, rumbling sounds, anomalous animal behavior, steaming activity, sulfurous odor, and drying vegetation. Questionnaires on observable manifestations of volcanic or seismic events were distributed to observers in communities in areas presently being monitored for volcanic or seismic activity by PHIVOLCS; these are collected according to set schedules, though unusual phenomena are reported immediately.

The ultimate aim of the program is to encourage local residents to participate actively and, in so doing, awaken the public’s awareness by increasing their knowledge of the dangers and risks posed by volcanic eruptions and earthquake occurrences. Preliminary results have shown that this program is indeed useful and could be adapted to other developing countries. Development of the scheme in geologically active areas could eventually lead to the proper implementation of an effective prediction, warning, and disaster-preparedness program.


Volcanic Eruption Earthquake Prediction Earthquake Occurrence Active Volcano Precursory Sign 
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Copyright information

© G.J.H. McCall, D.J.C. Laming and S.C. Scott 1992

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  • Perla J. Delos Reyes

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