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The Geochemistry of Central American Volcanic Gas Condensates

1970; Geological Society of America; Volume: 81; Issue: 10 Linguagem: Inglês

10.1130/0016-7606(1970)81[2891

1943-2674

Richard E. Stoiber, William I. Rose,

Geological and Geochemical Analysis

Research Article| October 01, 1970 The Geochemistry of Central American Volcanic Gas Condensates RICHARD E STOIBER; RICHARD E STOIBER Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755 Search for other works by this author on: GSW Google Scholar WILLIAM I ROSE, JR. WILLIAM I ROSE, JR. Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755 Search for other works by this author on: GSW Google Scholar Author and Article Information RICHARD E STOIBER Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755 WILLIAM I ROSE, JR. Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755 Publisher: Geological Society of America Received: 21 Oct 1969 Revision Received: 04 May 1970 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1970, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1970) 81 (10): 2891–2912. https://doi.org/10.1130/0016-7606(1970)81[2891:TGOCAV]2.0.CO;2 Article history Received: 21 Oct 1969 Revision Received: 04 May 1970 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation RICHARD E STOIBER, WILLIAM I ROSE; The Geochemistry of Central American Volcanic Gas Condensates. GSA Bulletin 1970;; 81 (10): 2891–2912. doi: https://doi.org/10.1130/0016-7606(1970)81[2891:TGOCAV]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 SocietyGSA Bulletin Search Advanced Search Abstract Results of analyses for Cl, F, SO4, Ca, Mg, Na, and K in 132 condensates from fumaroles of the Central American volcanoes Santiaguito, Fuego, Pacaya, Izalco, Cerro Negro, and Arenal are given. Each fumarole is of high temperature, greater than 150°C, and is located within 500 m of an active volcanic vent. Condensates were collected over a 5-yr period, August 1964-July 1969. The variation in chemistry of the condensates is shown to depend upon the fumarole location and the time of collection relative to the eruptive and cooling history of the volcano. Ground-water dilution also affects concentration because it is variable and cumulative. The data show that Cl and F in condensates decrease as the magma source is depleted and as the ground-water component in the fumarole increases. F is believed to be depleted by reaction with wallrock, as well. The alkalis, Na and K, are shown to come in part from the wallrock, and probably in part from the magma. Wallrock is suspected to be the chief source of Ca and Mg, as the Ca/Mg ratio in condensates is that of the wallrock. Fumaroles at main active vents are shown to be SO4 rich, with comparatively low CI/SO4 ratios. Fumaroles on flows are Cl-rich. The ratio CI/SO4 decreases at fumaroles in or near a main vent at the beginning of an eruptive period. Regular monitoring of the condensate at such fumaroles should enable prediction of eruptive periods months in advance, although the exact timing would vary with location. The practicality of the method depends upon the existence of accessible fumaroles. 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.