Lyell Collection
Geological Society, London, Memoirs
Lyell Centre  |   Lyell Collection  |   Subscriptions   |   Geological Society  |   Email alerts  |   Online bookshop  |   Help

Keywords:
Author:
Advanced search>>
This Article
Right arrow Full Text (PDF)
Right arrow References
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Isaacson, P. E.
Right arrow Articles by Sablock, P. E.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation
Geological Society, London, Memoirs; 1990; v. 12; p. 431-435;
DOI: 10.1144/GSL.MEM.1990.012.01.40
© 1990 Geological Society of London

Palaeozoic Geography

Devonian palaeogeography and palaeobiogeography of the Central Andes

P. E. Isaacson & P. E. Sablock

Department of Geology, University of Idaho, Moscow, Idaho 83843, USA

During Devonian time, western Gondwana (northern Chile, Bolivia, and Peru) witnessed a period of thick clastic rock deposition. The sialic Arequipa Massif, apparently a stable terrane since Precambrian time, supplied the bulk of the Bolivian intracratonic basinal sediments. Late Ordovician orogeny in northern Chile-northwestern Argentina included the emplacement of the Puna magmatic arc, with attendant plutonism. The resulting highland supplied coarsegrained sediments to northern Chile. Late Devonian(?) orogenesis deformed Early to Middle Devonian rocks in northern to central Peru. It is suggested that mid-Palaeozoic convergence was 'buffered' by the Arequipa Massif, giving little evidence of orogeny in the Bolivian Devonian-Carboniferous sequence. A highly endemic (Malvinokaffric) shelly fauna, indicative of high palaeolatitudes, occupied the region in Early Devonian (Emsian) time, while allochthonous (Eastern Americas Realm) faunas entered southern Peru. During Middle Devonian time a much lower diversity 'post-Malvinokaffric' fauna (consisting of the brachiopods Tropidoleptus, Globithyris, and other taxa) arrived, although a Malvinokaffric stock remained. These taxa arrived via the Amazonas and other eastern basins during a rotation of the region to lower latitudes and presumably warmer waters in Middle Devonian time.