The Purus Arch (Portuguese: Arco do Purus) is a basement high in Brazil that makes up the modern western boundary of the Amazon sedimentary basin.[1][2] The Purus Arch is thought to be a former graben of Middle Proterozoic age that was inversed in the Late Proterozoic.[2]

Although not obviously noticeable, today the Purus Arch crosses the Amazon River near the mouth of the Purus River. Following the water breach of the arch about 8–10 million years ago, the western (cf. Pebas Mega-wetland) and eastern parts of the present-day Amazon basin became a unified system, which played an important role in the biogeography of many aquatic organisms in the region.[3][4][5]

References edit

  1. ^ Morales L.G. (1957). "A study of the Upper Amazonas and its oil possibilities". Relatório Interno da Petrobras, Depex 822, 22 p.
  2. ^ a b Caputo, Mario Vicente; Amaral Soares, Emilio Alberto (2016). "Eustatic and tectonic change effects in the reversion of the transcontinental Amazon River drainage system". Brazilian Journal of Geology. 46 (2): 301–328. doi:10.1590/2317-4889201620160066.
  3. ^ Ivanyisky III, S.J.; Albert, J.S. (2014). "Systematics and biogeography of Sternarchellini (Gymnotiformes: Apteronotidae): Diversification of electric fishes in large Amazonian rivers". Neotrop. Ichthyol. 12 (3): 565–584. doi:10.1590/1982-0224-20130159.
  4. ^ Albert, J.S.; Lovejoy, N.R.; Crampton, W.G.R. (2006). "Mioscene tectonism and the separation of cis- and trans-Andean river basins: evidence from Neotropical fishes". Journal of South American Earth Sciences. 21 (1–2): 14–27. doi:10.1016/j.jsames.2005.07.010.
  5. ^ Amado, M.V.; Farias, I.P.; Hrbek, T. (2011). "A Molecular Perspective on Systematics, Taxonomy and Classification Amazonian Discus Fishes of the Genus Symphysodon". International Journal of Evolutionary Biology. 2011: 360654. doi:10.4061/2011/360654. PMC 3147135. PMID 21811676.