Tube-fed pahoehoe lava-flow features of Azorella Peninsula, Heard Island, southern Indian Ocean

• Published in: Polar Record
• Main Authors: Kiernan, Kevin, McConnell, Anne, Yates, Tony
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1998
• Subjects: General Earth and Planetary Sciences; Ecology; Geography, Planning and Development; Antarctic; Heard Island; Indian; Antarc*; Polar Record
• Online Access: http://dx.doi.org/10.1017/s0032247400025699; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0032247400025699

Abstract Azorella Peninsula on Heard Island in the sub-Antarctic comprises basaltic scoria that is overlain by basalt flows. Typical tube-fed pahoehoe flows characteristic of some Hawaiian-type volcanoes occur. The volcanic landforms of the peninsula include highly degraded volcano remnants and undissected scoria cones, pahoehoe flows, lava rises, tumuli, open vertical volcanic conduits, and lava tubes. Features produced by lava inflation are widespread but are generally of low topographic relief. Many detailed lava-flow features are preserved in dramatically fresh condition within the protected environment of lava tubes. They highlight the efficacy of the lava tubes in maintaining high temperatures and low viscosity of the flowing lava. The lava tubes on Heard Island are the only features of their kind hitherto recorded from Antarctic and sub-Antarctic latitudes.