Location Of Volcanic Centers Research Articles

The Cameroon line: its regularities and relation to African rifts

The unique Cameroon line, about 5000 km long (from St. Helena Isl. to Mt. Tibesti), crosses two principal domains: continental and oceanic. In the middle of it occurs the oldest active volcano on Earth (Mt. Cameroon). The continental and oceanic sections of the line are built up symmetrically as shown in the regular location of volcanic centers with similar alkali basaltic but a bit skewed at potassium or sodium side lithologies. The line has a riftogene origin and is parallel and bears some similarities to the much larger and metalliferous East African rift. Both are tied to the Congolese craton superstructure.

Eruptive style and location of volcanic centers in the Miocene Washington Cascade Range: Reconstruction from the sedimentary record

Primary and reworked pyroclastic material in the Ellensburg Formation of central Washington records middle and late Miocene volcanism in the Cascade Range despite the absence of correlative volcanics within the volcanic chain. Volcanics marking sources for Ellensburg detritus were eroded during late Neogene uplift. Facies patterns and paleocurrent data suggest that the bulk of the volcaniclastics were derived from a source near Bumping Lake; a K-Ar date for an intrusion in this area supports this conclusion. Depositional patterns and characteristics of the detritus allow hypothetical reconstruction of the style of volcanism during this period. Eruptive episodes began with modest-sized Plinian eruptions followed by extended periods of dome growth. Aggradation in adjacent sedimentary basins occurred principally in response to introduction of large volumes of lithic pyroclastic material during eruptive episodes.