Continuous GPS Observations on Mindanao
Mikio Tobita*, Hisashi Suito*, Tomokazu Kobayashi*,
Satoshi Kawamoto*, Masayuki Yamanaka*, Akira Suzuki*,
Toshiharu Enya*, Masaki Honda*, Tetsuro Imakiire*,
Artemio Luis**, Alfie Pelicano**, Teresito Bacolcol**,
and Takahiro Ohkura***
*Geospatial Information Authority of Japan, 1 Kitasato, Tsukuba, Ibaraki 305-0811, Japan
**Philippine Institute of Volcanology and Seismology (PHIVOLCS), Philippines
***Aso Volcanological Laboratory, Kyoto University, Japan
We installed three continuous GPS stations on Mindanao Island to provide a basis for enhancing the monitoring of crustal movements. Because there are frequent power outages and Internet connections are slow and unstable in this region, the data acquisition had to be improved by taking necessary hardware and software measures. The cGPS observations have revealed displacements related to plate motions, creep of the Philippine Fault, and a large earthquake. Evaluation of detectability of interplate slip has indicated that our cGPS stations have enhanced the monitoring capability advance from Mw7.2 to Mw6.5 on the coast of northeastern Mindanao.
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