Pahoehoe and pillow lavas from the Suguta Trough, South Turkana, Kenya

Abstract

SummaryThe pahoehoe and pillow lavas described show many common features of morphology. A finger-like or digital flow mechanism adequately accounts for the similarities although the growth mechanism of individual lobes is by markedly different processes. An important distinction is the time taken to develop a rigid crust and its subsequent expansion by fracturing and auto intrusion. This is rapidly achieved in pillow lavas but only occurs at a late stage in the pahoehoe forms. The main factors controlling the formation of these features are the environment of eruption, the volume of erupted material and the rate of eruption.