Charcoal reflectance as a proxy for the emplacement temperature of pyroclastic flow deposits

Research Article| July 01, 2005 Charcoal reflectance as a proxy for the emplacement temperature of pyroclastic flow deposits Andrew C. Scott; Andrew C. Scott 1Geology Department, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK Search for other works by this author on: GSW Google Scholar Ian J. Glasspool Ian J. Glasspool 1Geology Department, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK Search for other works by this author on: GSW Google Scholar Author and Article Information Andrew C. Scott 1Geology Department, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK Ian J. Glasspool 1Geology Department, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK Publisher: Geological Society of America Received: 17 Dec 2004 Revision Received: 03 Mar 2005 Accepted: 10 Mar 2005 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2005) 33 (7): 589–592. https://doi.org/10.1130/G21474.1 Article history Received: 17 Dec 2004 Revision Received: 03 Mar 2005 Accepted: 10 Mar 2005 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Andrew C. Scott, Ian J. Glasspool; Charcoal reflectance as a proxy for the emplacement temperature of pyroclastic flow deposits. Geology 2005;; 33 (7): 589–592. doi: https://doi.org/10.1130/G21474.1 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 Hot pyroclastic flow deposits often entomb and preserve vegetation as charcoal. When studied in polished section, this charcoal is highly reflective. Novel data from experimentally charred woods demonstrate that reflectance increases with both temperature and time. At temperatures above 250 °C, reflectance rises rapidly for the first hour, effectively stabilizing after 4 h for temperatures below 400 °C. However, for higher temperatures, reflectance only stabilizes after ∼24 h. Charcoalified woods from block and ash flow deposits generated by the Soufrière Hills volcano in Montserrat have yielded interpreted deposit temperatures, based on reflectance data, of 325–525 °C. These temperatures compare favorably with directly measured data (365–640 °C) from the same deposits, indicating that charcoal reflectance is useful as a temperature proxy for ancient pyroclastic flow deposits, particularly where magnetic or mineral data are absent for this purpose. However, caution should be exercised, as only a minimum temperature can be inferred where the heating duration of the deposit is unknown. Unlike magnetic or mineral data, temperature data from charcoalified woods can be obtained from reworked deposits, providing a valuable means of validating observations made about the style of eruption of volcanoes in ancient settings. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.