Volcaniclastic sediments from mid-oceanic Kolbeinsey Ridge, north of Iceland: Evidence for submarine volcanic fragmentation processes

Abstract

Research Article| November 01, 1994 Volcaniclastic sediments from mid-oceanic Kolbeinsey Ridge, north of Iceland: Evidence for submarine volcanic fragmentation processes Klas S. Lackschewitz; Klas S. Lackschewitz 1Geomar, Research Center for Marine Geosciences, Wischhofstrasse 1-3, D-24148 Kiel, Germany Search for other works by this author on: GSW Google Scholar Jonathan Dehn; Jonathan Dehn 1Geomar, Research Center for Marine Geosciences, Wischhofstrasse 1-3, D-24148 Kiel, Germany Search for other works by this author on: GSW Google Scholar Hans-Joachim Wallrabe-Adams Hans-Joachim Wallrabe-Adams 1Geomar, Research Center for Marine Geosciences, Wischhofstrasse 1-3, D-24148 Kiel, Germany Search for other works by this author on: GSW Google Scholar Author and Article Information Klas S. Lackschewitz 1Geomar, Research Center for Marine Geosciences, Wischhofstrasse 1-3, D-24148 Kiel, Germany Jonathan Dehn 1Geomar, Research Center for Marine Geosciences, Wischhofstrasse 1-3, D-24148 Kiel, Germany Hans-Joachim Wallrabe-Adams 1Geomar, Research Center for Marine Geosciences, Wischhofstrasse 1-3, D-24148 Kiel, Germany Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1994) 22 (11): 975–978. https://doi.org/10.1130/0091-7613(1994)022<0975:VSFMOK>2.3.CO;2 Article history 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 Klas S. Lackschewitz, Jonathan Dehn, Hans-Joachim Wallrabe-Adams; Volcaniclastic sediments from mid-oceanic Kolbeinsey Ridge, north of Iceland: Evidence for submarine volcanic fragmentation processes. Geology 1994;; 22 (11): 975–978. doi: https://doi.org/10.1130/0091-7613(1994)022<0975:VSFMOK>2.3.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 Volcaniclastic sediments of the active Kolbeinsey Ridge, north of Iceland, reflect changing fragmentation mechanisms due to increasing sea level during the last deglaciation. Glass shards deposited on the western flank of the mid-oceanic ridge before 13.4 ka are vesicular (20%-60%), whereas shards deposited since 13.4 ka are mostly vesicle free and of hyaloclastic origin. The vesicle-rich shards display morphology thought to be atypical for submarine eruptions at this depth (400-500 m). The environmental conditions during the deposition of these layers (regional ice cover, more than 200 km from the nearest subaerial source) preclude a subaerial origin for these shards. We propose an eruption mechanism in which hot vesiculating bombs from a low-energy eruption are transported upward through the water column by convection. These particles reach their volcanic fragmentation depth (VFD) and undergo secondary fragmentation, creating the vesicle-rich shards recovered near the ridge. Rising sea level since the end of the last glaciation was sufficient to prevent the erupted particles from reaching the VFD, thus ending the formation of vesicle-rich shards. This model explains the presence of vesicular shards in sediments of mid-oceanic ridges where no subaerial source can be inferred. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.