Executive Committee Range

The Executive Committee Range is a north-south chain of five large shield volcanoes in Marie Byrd Land, West Antarctica, named, from north to south, Mount Cumming, Mount Hartigan, Mount Sidley, Mount Waesche and Mount Boyd. Mount Sidley, already documented in this section as the tallest of the five and the highest volcano in Antarctica, anchors the range's southern end. The chain sits within the wider Marie Byrd Land Volcanic Province, one of the largest subglacial volcanic provinces on Earth, and its volcanoes are built mainly from alkaline basaltic and trachytic lava consistent with the intraplate, rift-related volcanism found across the province. Radiometric dating of the range's volcanic rock shows the five edifices grew at different times, suggesting the range formed through episodic eruptions along the same underlying structural trend rather than in a single event. This entity documents the Executive Committee Range specifically as a geological formation, a chain of five shield volcanoes in the Marie Byrd Land Volcanic Province.