|Region:||Africa and Red Sea|
|Duration of observation:||Dec 2006 - April 2010|
|Inferred cause of deformation:||Magmatic|
|Characteristics of deformation:|
High resolution optical imagery and InSAR data were used to study an eruption at Jebel at Tair that occurred between Sept 2007 and Jan 2008. Xu and Jónsson (2014) compared pre- and post-eruptive optical imagery to identify fissures and new scoria cones. They identified that 5.9 ± 0.1 km2 of new lava was extruded onto the island. They used decorrelation in the InSAR images indicates that lava flowed both to the western and to the northeastern part of the island after the start of the eruption, while later lavas were mainly deposited near the summit and onto the north flank of the volcano. They also note that no volcano-wide pre- or post-eruption uplift is observed, suggesting a deep magma source.
They model the dyke intrusion feeding the eruption as a tensile dislocation model. The model results show that the orientation of the dike is perpendicular to the Red Sea rift, implying that the local stresses within the volcanic edifice are decoupled from the regional stress field.
|Reference:||Xu, W., & Jónsson, S. (2014). The 2007–8 volcanic eruption on Jebel at Tair island (Red Sea) observed by satellite radar and optical images. Bulletin of Volcanology, 76(2), 1-14.|
Jebel at Tair is a 3 km wide basaltic oval stratovolcano in the Red Sea. The island is of Holocene age, and had numerous eruptions in the 18th, 19th and 20th centuries. Radial fissures extend from the summit. High resolution optical imagery is available in Xu and Jónsson (2014). NASA Landsat7 image (worldwind.arc.nasa.gov)