UH Hilo Center for Maunakea Stewardship - Research Library

Geology and volcanology of the Hawaiian Islands

Author:
Walker, George P. L.
Title:
Geology and volcanology of the Hawaiian Islands
Periodical:
Pacific Science
Year:
1990
Volume:
44
Pages:
315-347
Subject:
Geology Hawaii Volcanism Volcanoes
Summary:
This is, in part, a review article and synthesis of the present state of knowledge of the geology of the Hawaiian Islands. It summarizes the knowledge of the geology of Hawaii and concentrates on aspects that are not usually covered by review articles. The ideas on hotspots and mantle plumes are applied to the specific example of Hawaii, the eight volcanic systems currently nourished by the hotspot are identified, and gross differences in magma-supply rate are related to position of these systems on the hotspot. Also discussed is the role played by the level of neutral buoyancy in distributing incoming magma between magma chambers, rift zones, intrusions, and surface flows. This is important because volcanic edifices may expand nearly as much by growth of subsurface intrusions as by surface lava outpourings even though discoveries have shown how strongly volcano growth is countered by subsidence and major collapses. This article also briefly describes the styles of volcanism in Hawaii as well as ideas on how the formation of aa and pahoehoe lava depends on the eruption discharge rate as well as the highlights of each volcano. Speculations regarding geographical distribution of the volcanoes is also described in addition to how, by postulating that a considerable strike-slip motion occurred on two faults, a much more orderly arrangement of volcano and rift-zone alignments appears, that leads to a dynamic model of island-chain growth that is simpler then current models. Alternating sequences of southeast and west-southwest alignments is also presented. This sequence starts from Kauai and works toward the southeastern part of the Hawaiian island chain. These alignments may be respectively related to fractures that are propagated against the plate motion direction, (as a result of extensional stresses that is due to the diverging flow in the mantle plume), and along faults of the Molokai fracture zone.
Label:
Geology
URL:
http://hdl.handle.net/10125/1287
Collection:
Periodicals