Seulawah Agam

Volcano number:261020
Region:Indonesia
Country:Sumatra
Geodetic measurements?Yes
Deformation observation?Yes
Measurement method(s):GPS - continuous, GPS - campaign
Duration of observation:03/2004-04/2012
Inferred cause of deformation:Faulting/tectonics
Characteristics of deformation:

While no geodetic studies have been performed specifically focusing on Seulawah Agam (most of the existing literature focuses on studies concerning its geothermal source), one regional study (Tabei et al, 2015) notes decaying postseismic deformation in the Aceh region following the major earthquake on 26th December 2004 (the Sumatran-Andaman earthquake, also called the SAE) on the Northern Sumatran Fault. This study used GPS measurements to observe the deformation over a seven year period, between 2004 and 2012.

The Tabei study utilised the Aceh GPS Network, consisting of twenty-four sites (seven continuous and seventeen campaign) covering an area of 4000 km2 within Aceh province (3 N 95 E – 7 N 97 E). Seulawah Agam is located within the northernmost extreme of the study region.

The observed deformation within the study period was significantly greater in the horizontal component than the vertical; the total horizontal displacement over the seven years was approximately one metre trenchward (southwest). The rate of deformation decayed steadily in a roughly linear trend between 2004 and 2011, which the authors contribute to the postseismic viscoelastic effect.

Reference:Tabei, T. et al, 2015. Geodetic and geomorphic evaluations of earthquake generation potential of the Northern Sumatran Fault, Indonesia. International Association of Geodesy Symposia, pp 1-8. DOI: 10.1007/1345_2015_200
Location:95.658, 5.448

Smithsonian Institute Global Volcanism Program, 2015