Of the more than twenty historically active volcanoes in Antarctica and the sub-Antarctic region only two, to our knowledge, host any ground-based monitoring instruments. Moreover, because of their remoteness, most of the volcanoes are seldom visited, thus relegating the monitoring of volcanism in this region almost entirely to satellites. In this study, high temporal resolution satellite data from the Hawaii Institute of Geophysics and Planetology's MODVOLC system using MODIS (Moderate Resolution Imaging Spectroradiometer) are complemented with high spatial resolution data (ASTER, or Advanced Spaceborne Thermal Emission and Reflection Radiometer, and similar sensors) to document volcanic activity throughout the region during the period 2000–10. Five volcanoes were observed in eruption (Mount Erebus, Mount Belinda, Mount Michael, Heard Island and McDonald Island), which were predominantly low-level and effusive in nature. Mount Belinda produced tephra, building a cinder cone in addition to an extensive lava field. Five volcanoes exhibited detectable thermal, and presumed fumarolic, activity (Deception, Zavodovski, Candlemas, Bristol, and Bellingshausen islands). A minor eruption reported at Marion Island was not detected in our survey due to its small size. This study also discovered a new active vent on Mount Michael, tracked dramatic vent enlargement on Heard Island, and provides an improved picture of the morphology of some of the volcanoes.

Orbital spectroscopy and laboratory analyses are utilized to identify major geochemical variations throughout the Ferrar Dolerite exposed in the McMurdo Dry Valleys (MDV) of Antarctica. Our laboratory results highlight the range of primary and secondary chemical and spectral variations observed throughout the dolerite, and provide the necessary calibration for detailed orbital investigations. Pure dolerite units are identified and analysed throughout the MDV using Advanced Land Imager (ALI) and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) orbital datasets. In conjunction with our laboratory analyses, orbital analyses indicate that the dolerite sills are dominated by MgO concentrations of c. 6–7 wt% except where influenced by orthopyroxene-laden magmatic injections, where MgO concentrations can reach as high as 32.5 wt%. ASTER analyses also indicate that spectrally significant alteration is limited primarily to surfaces dominated by fine-grained dolerites, which form and preserve well developed alteration rinds due to their resistance to physical erosion. The archetype of these secondary signatures is Beacon Valley, where a combination of cold, dry, and stable environmental conditions and the presence of fine-grained dolerites results in strong alteration signatures. This work provides unprecedented spatial coverage of meso- and macro-scale geochemical features that, until now, have only been identified in field and laboratory investigations.