Mineralogy and geochemistry of clay samples from active hydrothermal vents off the north coast of Iceland.

Lackschewitz, Klas, Botz, R., Garbe-Schönberg, C.-Dieter, Scholten, J. and Stoffers, P. (2006) Mineralogy and geochemistry of clay samples from active hydrothermal vents off the north coast of Iceland. Marine Geology, 225 (1-4). pp. 177-190. DOI 10.1016/j.margeo.2005.07.002.

[img] Text
Lackschewitz.pdf - Published Version
Restricted to Registered users only

Download (382Kb) | Contact

Supplementary data:

Abstract

Active hydrothermal vent sites were sampled during 1997 in a series of submersible dives at the active Grimsey (GHF) and Kolbeinsey (KHF) hydrothermal fields off the north coast of Iceland. This study focuses on secondary clay minerals which were formed in two different settings. The GHF is characterized by the presence of clay minerals precipitated within active chimneys. By contrast, the KHF is characterized by the presence of secondary clay minerals, which are the products of hydrothermal alteration of lava fragments. Based on XRD, electron microprobe and ICP-MS analyses, the dominant clay mineral in both hydrothermal fields is saponite (Mg-rich smectite). Chlorite and chlorite–smectite mixed-layer minerals also occur at the KHF. The Mg-rich nature of saponite from the GHF chimneys suggests intense Mg metasomatism in the mixing zone where hydrothermal fluids interact with seawater at temperatures of 250 °C. Saponite formation resulted in the additional uptake of Cu, Zn, and Pb. Enrichment in Ba is evident in the almost pure saponite from the KHF. Based on oxygen isotope data, the saponite formation at the KHF occurred at 148 °C, which is close to the maximum measured fluid temperature of 131 °C in this field.

Document Type: Article
Keywords: Grimsey hydrothermal field, Kolbeinsey hydrothermal field, hydrothermal precipitation, hydrothermal alteration, saponite
Research affiliation: Kiel University
OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-MUHS
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1016/j.margeo.2005.07.002
ISSN: 0025-3227
Date Deposited: 03 Dec 2008 16:50
Last Modified: 03 Aug 2017 12:30
URI: http://oceanrep.geomar.de/id/eprint/1390

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...