Sumatran GPS Array (SuGAr)
The Sumatran GPS Array (SuGAr) spans more than a thousand kilometres of the convergent plate boundary between Indo-Australian and Asian tectonic plates. With 49 GPS stations, this network provides a wealth of information on the Sunda megathrust and the Sumatran fault.
This array has particular scientific value for three reasons:
- Numerous GPS stations are located on islands that directly overlie the locked sections of the Sunda megathrust: they are perfectly situated to record interseismic, coseismic and postseismic deformation of the upper part of the subduction zone, which is unique in the world.
- SuGAr geodetic data complement centennial and millennial paleoseismologic time series collected from coral micro-atolls in the same locations. SuGAr data can therefore be inserted into the context of several earthquake cycles.
- Several great earthquakes have occurred along the Sumatran margin since the network has been implemented. SuGAr thus provides a great opportunity to understand pre- and post-seismic behaviour of the megathrust by monitoring tectonic deformation above it.
Map of Sumatran GPS Array (SuGAr) in Indonesia
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TRTK GPS Station
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Dr Iwan Hermawan checking on the instrument box during the SuGAR maintenance trip in 2019 (Source: Iwan Hermawan)
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Dr Iwan Hermawan with local staff after a maintenance field trip to Sumatra, Indonesia in 2019 (Source: Unknown)
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A GPS station in the Mentawai islands, Indonesia in 2020 (Source: Iwan Hermawan)
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A GPS station in Bojo island, North Sumatra, Indonesia (Source: Unknown)
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A local engineer with GPS antenna at a GPS station on Siberut island, Indonesia in 2019 (Source: Iwan Hermawan)
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Local engineers installing new solar panels during the 2019 SuGAR maintenance field trip (Source: Iwan Hermawan)
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Inside a GPS station instrument box, SuGAR maintenance field trip, 2019 (Source: Iwan Hermawan)
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Dr Dannie Hidayat on a boat to the Mentawai Islands, Indonesia in 2019 (Source: Iwan Hermawan)