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The Gran Sabana: The World’s Finest Quartzite Karst?

  • Robert A. L. Wray
Chapter

Abstract

The Gran Sabana in tropical Venezuela, with its huge mist shrouded, mesa or tepui that tower over 1,000 m above the lowlands, undoubtedly form one of the world’s more spectacular landscapes. These vertically walled quartzite table mountains are composed of Pre-Cambrian Roraima Group quartzites and sandstones, and crest a series of regional planation surfaces. Because of their isolation the summits are often biologically unique. Extremely long periods of geologic stability and weathering have produced a vast range of karstic forms in the quartzites, such as caves, towers, grikes, and smaller karren. Quartzite is not a rock usually associated with karst forms, but here they are expressed better than anywhere else in the world. Sections of the Gran Sabana and its tepui are listed as World Heritage, and its remoteness and often-poor accessibility possibly make it the most poorly explored of the great geomorphological landscapes.

Keywords

karst quartzite solutional weathering table mountain Venezuela 

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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Robert A. L. Wray
    • 1
  1. 1.University of WollongongNew South WalesAustralia

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