Geochemistry of Cenozoic ash layers from the Kerguelen Plateau ...

• Main Authors: Morche, Wolfgang, Hubberten, Hans-Wolfgang, Mackensen, Andreas, Keller, Jörg
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 1992
• Subjects: Drilling/drill rig; Leg120; Joides Resolution; Ocean Drilling Program ODP; Heard Island; Kerguelen Islands
• Online Access: https://dx.doi.org/10.1594/pangaea.757631; https://doi.pangaea.de/10.1594/PANGAEA.757631

Geochemical investigations were conducted on 10 discrete ash layers and 22 samples of dispersed ash accumulations from Sites 747, 749, and 751 of Ocean Drilling Program (ODP) Leg 120 to the Kerguelen Plateau in the southern Indian Ocean. The chemical data obtained from some 400 single-grain glass analyses allow the characterization of two rock series. The first consists of transitional to alkali basalts; the second, mainly of trachytes with subordinated rhyolites, all reflecting the characteristic magmatological evolution of the Kerguelen Plateau as a hotspot-related volcanism. Chemical correlation with possible source areas indicates that the ashes were most probably erupted from the Kerguelen Islands. The investigated ash layers clearly reflect the Oligocene to Quaternary changes in the composition of the volcanic material recorded from the Kerguelen Islands. In addition to the Kerguelen Islands, Heard Island, Crozet Island, and other sources may have contributed to deposition of the tephras. Pleistocene ... : Supplement to: Morche, Wolfgang; Hubberten, Hans-Wolfgang; Mackensen, Andreas; Keller, Jörg (1992): Geochemistry of Cenozoic ash layers from the Kerguelen Plateau (Leg 120): a first step toward a tephrostratigraphy of the Southern Indian Ocean. In: Wise, SW; Schlich, R; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 120, 151-160 ...