Chapter 16 The Pacific Northwest

              Volcanoes in Honolulu 

The Pacific Northwest does not apply to Honolulu it refers to "western Oregon, western Washington, British Columbia west of the Rocky Mountains, and the southeastern panhandle of Alaska."  (Hardwick, Pg. 303) But I will be discussing the volcanoes in Honolulu and its activity.
  The two primary volcanoes in Honolulu have not erupted for over a million years.  "The age trend of the volcanoes is thought to be due to the way in which the islands are built on the moving sea floor of the North Pacific Ocean: the Pacific Ocean is mostly floored by a single tectonic plate that is moving over the layer in the Earth known as the Asthenosphere." The movements moves northwest compared to the layers below it at a rate of 5 to 10 cm/yr and this fixed spot deeper in the earth where the magma forms a new volcano where it punches through the plate creating and island.  The Hawaiian islands are believed to be formed from such "hot spot" Hawaii is constructed of 5 major volcanoes: Kilauea, Mauna Loa, Mauna Kea, Hulalai, and Kohala.  The most largest active is the Mauna Loa and the most productive is the Kilauea on Earth. 

Reference
http://hawaiideptland.custhelp.com/app/answers/detail/a_id/67/~/what-are-the-natural-resource