TheBella Bella and Gale Passage dike swarms are two paralleldike swarms on theCentral Coast ofBritish Columbia, Canada.[1] They range in age from 14.5 to 12.5 million years old.[1][2] They are both chemicallybimodal, consisting of rocks such asbasalt,trachyte andcomendite. They form the westernmost extent of theAnahim Volcanic Belt onAthlone Island,Dufferin Island andDenny Island.[3]
The Bella Bella and Gale Passage dike swarms arepetrographically similar to theshield complexes in the central Anahim Volcanic Belt. As a result, the swarms are thought to represent the roots of aperalkaline magma system in which they are the magma conduits connecting the underlyingmagma chamber to the volcanic centre at the surface, which has been extensively eroded to remnants of eruptivebreccia.[3]
 | This article about a specific geological feature inBritish Columbia,Canada is astub. You can help Wikipedia byexpanding it. |