Aswa Dislocation

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Location of the Aswa Dislocation Aswa Dislocation.svg
Location of the Aswa Dislocation

The Aswa Dislocation, also called the Aswa mylonite belt, Aswa Lineament or Aswa Shear Zone is a north-west trending ductile shear zone that runs to the east of Lake Victoria in East Africa. [1]

Contents

Extent

The lineament dates to the Precambrian era and thus is much older than the East African Rift System. It probably extends northwest to Darfur in Sudan, perhaps along the Abu Gabra Rift, and perhaps southeast to the Lindi fault zone on the Indian Ocean coast, passing through the Kilimanjaro and Elgon volcanic centers. [2]

Connection to the East African rift system

The fault seems to have been partly reactivated during the Neogene in the section between the Albertine and Gregory rifts, and along its southern extension towards the Indian Ocean. [3] The reactivated section of the Aswa lineament connects the eastern and western branches of the East African rift system. [4] It seems also to truncate the Nyanza rift, which extends ENE from Lake Victoria. [1] The section of the Aswa Dislocation between the two rifts forms part of the boundary between the Somali Plate and the African Plate. [5]

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References

  1. 1 2 Rach 1992, p. 221.
  2. Rosendahl 1987, p. 461.
  3. Chorowicz, Le Fournier & Vidal 1987, p. 495.
  4. Volon et al. 1998.
  5. Rosendahl 1987, p. 450.
Sources