Today is




Takahiro Ohkura1,a , Takehide Nakano2,b, Glenda M. Besana3, Michael J. Sicat3,

Yoshinobu Hoso2, Enrico Mangao3, Ireneo Geraldo3, Jessie A. Daligdig3,

Masataka Ando2,b and Raymundo S. Punongbayan3

1Faculty of Integrated Human Studies, Kyoto University, Japan
2Disaster Prevention Research Institute, Kyoto University, Japan.
3Philippine Institute of Volcanology and Seismology, Philippines
aNow at: Aso Volcanological Laboratory, Japan
bNow at: School of Science, Japan






In order to detect crustal movement related to the origin of the Macolod Corridor (MC), Philippines, GPS measurements were undertaken in and around this region. Thirteen stations were established and four campaigns were made from April 1996 to April 1997 with 3 - 5 days sessions at each station. After analyzing data using Bernese GPS software, most of the stations in southern part of the study area were found to be moving toward ENE or East at a rate of about 2-3 cm per year relative to northwestern part. Calculated strain tensors show a large amount of counterclockwise motion in the southern part.

The above observations are consistent with the block motion after 4Ma determined through a recent paleomagnetic research and a K-Ar dating study of volcanic rocks in and around the MC. It is possible that crustal movements detected by GPS observations are closely related to the formation process of the MC.




Geological Society of the Philippines

Unit 250, 2nd Floor, Cityland Pioneer, 128 Pioneer Street, Mandaluyong City, Philippines

Tel: +(63-2) 633-9025