Journal articles
Seismicity of the Sunda Strait: Evidence for crustal extension and volcanological implications
Abstract : The Sunda Strait is located in the transitional zone between two different modes of subduction: the Java frontal subduction and the Sumatra oblique subduction. This setting implies that the Sunda Strait region is a key to the understanding of the geodynamic processes involved. In order to study the shallow seismicity, a microearthquake survey was carried out in that region. Twelve stations, accurately located by the aim of satellite positionning, recorded about 300 local events in the summer 1984. From this set, 174 shallow earthquakes have been precisely located. The results of this study reveal that the crustal earthquakes in the Sunda Strait area occurs in three main areas: (1) beneath the Krakatau complex, where earthquakes are generated by double-couples and are of tectonic origin; (2) inside a graben in the western part of the strait; and (3) in a more diffused zone to the south of Sumatra. The individual and composite focal mechanisms from the events inside the strait show an extensional regime. A stress tensor, which have been deduced from the individual focal mechanisms of earthquakes of the Krakatau group shows that the tensional axis is oriented N130øE. This study confirms that the Sunda Strait is in an extensional tectonic regime as a result of the northwestward movement of the Sumatra sliver plate along the Semangko fault zone.
Cited literature [3 references]
https://hal-insu.archives-ouvertes.fr/insu-01354283
Contributor : Eva Fareau Connect in order to contact the contributor
Submitted on : Thursday, August 18, 2016 - 12:06:12 PM
Last modification on : Tuesday, November 23, 2021 - 11:12:14 AM
Long-term archiving on: : Saturday, November 19, 2016 - 7:26:23 PM
Contributor : Eva Fareau Connect in order to contact the contributor
Submitted on : Thursday, August 18, 2016 - 12:06:12 PM
Last modification on : Tuesday, November 23, 2021 - 11:12:14 AM
Long-term archiving on: : Saturday, November 19, 2016 - 7:26:23 PM
File
tect-1991-10-17-harjono.pdf
Publisher files allowed on an open archive