Volcano spacings and lithospheric attenuation in the Eastern Rift of Africa

doi:10.1016/0012-821X(76)90166-7

Earth and Planetary Science Letters

Volume 33, Issue 1, November 1976, Pages 126-144

https://doi.org/10.1016/0012-821X(76)90166-7 Get rights and content

Abstract

The Eastern Rift of Africa runs the gamut of crustal and lithospheric attenuation, from undeformed shield through attenuated rift margin to active neo-oceanic spreading zones. It is therefore peculiarly well suited to an examination of relationships between volcano spacings and crust/lithosphere thickness. Although lithospheric thickness is not well known in Eastern Africa, it appears to have direct expression in the surface spacing of volcanoes for any given tectonic regime. This applies, whether the volcanoes are essentially basaltic, silicic or alkaline-carbonatitic. We find no evidence for control of volcano sites by a pre-existing fracture grid in the crust.

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