HR: 1340h
AN: V13B-1350    [Abstracts]
TI: Shallow plumbing systems in mud volcanoes (Azerbaijan)
AU: * Mazzini, A
EM: adriano.mazzini@fys.uio.no
AF: Physics of Geological Processes, University of Oslo, POBOX 1048 - Blindern, Oslo, 0316, Norway
AU: Svensen, H
EM: henrik.svensen@fys.uio.no
AF: Physics of Geological Processes, University of Oslo, POBOX 1048 - Blindern, Oslo, 0316, Norway
AU: planke, S
EM: planke@vbpr.no
AF: Physics of Geological Processes, University of Oslo, POBOX 1048 - Blindern, Oslo, 0316, Norway
AU: planke, S
EM: planke@vbpr.no
AF: VBPR, Research Park, Oslo, 0349, Norway
AU: Akhmanov, G G
AF: Moscow State University, Faculty of Geology, Vorobjevy Gory, Moscow, 119992, Russian Federation
AU: Guliyev, I
AF: Geology Institute Azerbayjan, Husein Av. 29A, Baku, N/A, Azerbaijan
AU: Johansen, H
AF: Institut for Energiteknikk, PO.Box 40, Kjeller, 2027, Norway
AU: Fallick, T
AF: Scottish Universities Environmental Research Centre, Rankine Av., East Kilbride, Glasgow, G75 0QF, United Kingdom
AB: Studies of mud volcano piercement structures intensified during the last decades in order to better understand both the eruptive and dormant stages and ongoing processes, from the source region to the surface. Our recent field studies and analyses in dormant Azeri mud volcanoes showed the presence of different seepage sites with an interconnected and intricate plumbing system in the near surface of the volcano craters. Gryphons and pools represent the two dominant seepage modes in the dormant mud volcanoes in Azerbaijan. Shallow water reservoirs appear to feed the water dominated pools. At these locations the water temperatures is controlled by external air temperature and the higher salinities (up to 42000 ppm) are ascribed to stronger evaporation processes. In contrast, evaporation is less effective in the mud dominated gryphons (salinities approx 900 ppm) that have deeper roots as also suggested from the lithology and isotopic analyses. Gryphons have stable temperatures during warm and cold season. Water isotopic analyses reveal little influence from meteoric fluids while the seeping gas has a general mixed thermogenic-biogenic signature. Reverse correlation between d13C in CH4 and CO2 supports the hypothesis of shallow chambers located at different depths where biogenic methane is produced. Deep reservoirs reveal the presence of thermogenic gas that rising mixes with shallow biogenic methane.
UR: http://folk.uio.no/adrianom
DE: 8434 Magma migration and fragmentation
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting