Petrology, geochemistry, S, Cl and F abundances, and S oxidation state of sideromelane glass shards from Pleistocene ash layers north and south of Gran Canaria (ODP Leg 157)
Article Abstract:
Submarine eruptions northeast of Gran Canaria are believed to have resulted in sideromelane glass shards at Sites 953. Glasses deposited at Site 954, meanwhile, are mostly volcaniclastic material of shallow water submarine and subaerial eruptions on Gran Canaria and Tenerife. Glasses at Site 956 are a result of submarine or explosive eruptions on Tenerife. These were the results of an analysis of sideromelane glass particles from Pleistocene ash layers drilled at three sites to determine their mineralogy and chemical composition.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1998
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The use and misuse of the fH2 sensors: a discussion of the paper by Dachs (1994). (response to E. Dachs, Contributions to Minerology and Petrology, vol. 117, p. 229)
Article Abstract:
The fH2-sensor measurements presented in a study on annite stability are evaluated. Questions are raised on the study's equilibrium fH2 sensor measurements for the reaction annite = sanidine + magnetite + H2. It is argued that measurements are equilibrium values because of the effects of the water-based pressure medium on the redox state of the sample used in the study and the fact that demonstrating osmotic equilibrium does not ensure complete equilibrium.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1997
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Annite stability revised: hydrogen-sensor data for the reaction annite = sandine + magnetitie + H2: additional results and reply to Chou
Article Abstract:
Responses to the comment on a study on annite stability are presented. The comment stated that the fH2-sensor values measured in the study cannot be considered equilibrium values in the system annite-sanidine-magnetite-water (ASMW). However, it is argued that the fH2 values presented in the ASMW system at constant pressure and temperature correspond to various annite compositions and do not reflect a lack of equilibrium.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1997
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