The Owen Fracture Zone (OFZ), though misnamed as a fracture zone, is a transform fault in the northwest Indian Ocean that separates the Arabian and African plates from the Indian plate. Extending north-northeast from where the Carlsberg Ridge meets the Sheba ridge in the south to the Makran Subduction Zone in the north, it represents the port side of the northward motion of the Indian subcontinent during the Late Cretaceous–Palaeogene break-up of Gondwana.[1] Slip along the Owen Fracture Zone is occurring at 2 mm (0.079 in)/yr, the slowest rate on Earth, which means the Arabian plate moves northward faster than the Indian plate (4 vs. 2 mm/yr).[2]
In some usages, the name Owen Transform Fault is used to denote the short section between the end of the Aden-Sheba ridge and the Carlsberg Ridge.[3] Additionally, this area has been called the Aden–Owen–Carlsberg triple junction, although the Carlsberg Ridge is offset 330 km (210 mi) from the point where the Owen Fracture Zone/fault intersects the Sheba segment of the Aden Ridge.[4]
The Owen Fracture Zone is named after HMS Owen that identified the 'fracture line' in April/May 1963.[5] The Owen fracture Zone and the Dalrymple Trough north of it (named after HMS Dalrymple surveyed the area together with HMS Owen) form the modern boundary between the Arabian and Indian plates. [6]
- ^ Bird 2001, p. 152
- ^ Fournier et al. 2011, Introduction, p. 247
- ^ Gordon & DeMets 1989, Introduction, pp. 5560–5563
- ^ Fournier et al. 2010, Main Tectonic Features, pp. 2–3
- ^ "HMS Owen, British survey ship, post-WW2". Naval-history.net. Archived from the original on 2012-04-18. Retrieved 2012-03-30.
- ^ Fournier et al. 2008, Geodynamic setting of the AOC triple junction, pp. 4–5