Portal de Periódicos da CAPES

Volcanic spreading on Mauna Loa volcano, Hawaii: Evidence from accretion, alteration, and exhumation of volcaniclastic sediments

2003; Geological Society of America; Volume: 31; Issue: 5 Linguagem: Inglês

10.1130/0091-7613(2003)031 2.0.co;2

1943-2682

Julia K. Morgan, David A. Clague,

Geological and Geochemical Analysis

Research Article| May 01, 2003 Volcanic spreading on Mauna Loa volcano, Hawaii: Evidence from accretion, alteration, and exhumation of volcaniclastic sediments Julia K. Morgan; Julia K. Morgan 1Department of Earth Science, Rice University, Houston, Texas 77005, USA Search for other works by this author on: GSW Google Scholar David A. Clague David A. Clague 2Monterey Bay Aquarium Research Institute, Moss Landing, California 95039, USA Search for other works by this author on: GSW Google Scholar Geology (2003) 31 (5): 411–414. https://doi.org/10.1130/0091-7613(2003)031 2.0.CO;2 Article history received: 04 Sep 2002 rev-recd: 21 Dec 2002 accepted: 03 Jan 2003 first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Julia K. Morgan, David A. Clague; Volcanic spreading on Mauna Loa volcano, Hawaii: Evidence from accretion, alteration, and exhumation of volcaniclastic sediments. Geology 2003;; 31 (5): 411–414. doi: https://doi.org/10.1130/0091-7613(2003)031 2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract A transect of submersible dives across the submarine west flank of Mauna Loa volcano yields compelling evidence for volcanic spreading and associated hydrothermal circulation during volcano growth. A frontal bench at the toe of the flank, formerly thought to be a downdropped block of Mauna Loa, contains a mix of volcaniclastic lithologies, including distally derived siltstone, mudstone, and hyaloclastite. The bench is overlain by bedded gravels and subaerially erupted pillow flows derived from local shoreline-crossing lava flows. The volcaniclastic strata in the bench were offscraped, uplifted, and accreted to the edge of the flank, as it plowed seaward into the surrounding moat. The accreted strata underwent significant diagenesis, through deep burial and circulation of hydrothermal fluids expelled from porous sediments beneath the volcano. Timing constraints for bench growth and breakup suggest that catastrophic failure of the subaerial edifice ca. 250–200 ka triggered volcanic spreading by reducing stresses resisting basal sliding and rift-zone inflation. Increased eruptive activity, and westward migration of Mauna Loa's southwest rift zone, gradually rebuilt the massive flank, arresting slip prior to detachment of the Alika 2 debris avalanche ca. 120 ka. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.