Great Rift Valley Great Rift Valley The Great Rift Valley is a continuous geographic trench, approximately in length, that runs from Lebanon's Beqaa Valley in Asia to Mozambique in Southeastern Africa. The name continues in some usages, although it is today considered geologically imprecise as it combines features that are today regarded as separate, although related, rift and fault systems. Today, the term is most often used to refer to the valley of the East African Rift, the divergent plate boundary which extends from the Afar Triple Junction southward across eastern Africa, and is in the process of splitting the African Plate into
Volcanic history of the Northern Cordilleran Volcanic Province of the Omineca and Bear rivers, The Thumb rises with a topographic prominence of above gently sloping benchland near the crest of the Connelly Range. It is the largest among a cluster of seven steep-sided volcanic plugs associated with dikes, lava flows and remnants of cinder cones. Ne Ch'e Ddhawa, an extinct volcano in the Fort Selkirk Volcanic Field of central Yukon, reaches a height of near the junction of the Pelly and Yukon rivers. It was erupted subglacially under the Cordilleran Ice Sheet between 0.8 and one million years ago, depositing hyaloclastite tuffs, breccias and pillow breccias that now