Earthquake is very potential to occur along Sumatra and Seulimeum faults, without being predicted. To observe it, TDMRC Unsyiah’s geophysicists and seismologists installed 40 seismometers covering Sumatra and Seulimeum faults, Seulawah, Sabang Island, as well as Krueng Aceh basin. The installations were carried out in accessible areas.
In three-day long deployment starting on December 21 to 24, 2019, three teams of Geohazards TDMRC brought the instruments known as Zland Notch (ZN) 3C 5Hz around Banda Aceh and remote locations; Lhoknga-Leupung, and Seulawah volcano. The instrument uses a geophone sensor with flat to a velocity of bandwidth 0.05 Hz to 50Hz which is capable to record data even in ambient noises. It can record signals from about 30 seconds up to 120 seconds. This sensor has a dynamic range above 24 dB.
In determining the field, it is based on geological factors that tend to change laterally, investigating its effect on the ground shape due to seismic waves. Far from village road, water streams, tall poles, dense and tall trees, and soft ground are considered ideal characteristics and conditions to produce the highest quality of seismic record. As for power supply, the seismometer can endure for 35 days, supposing the device is 24 hours activated.
A day before the deployment, Dr. Muksin Umar, the coordinator of Geological Hazard cluster of TDMRC held a seismometer training together with Dr. Chen Weiwen from Earth Observatory of Singapore (EOS) of NTUS. Several students of the Physics Department of Unsyiah took part in the training on device installation, seismic data acquisition system and things prohibited during the deployment.
The team installed and recorded all the locations of the instrument in detail so that it was easily recognized when downloading data. “Because the ZN lies on land, it will be difficult to find the locations of the device after a month,” says principal investigator, Dr. Muksin. He added that, at the end of January, the geohazard team will be back to the locations along with research fellows of EOS to analyze the data.