McDonald Islands (volcano) McDonald Islands (volcano) The McDonald Islands () are the peaks of a volcano in the southern Indian Ocean in the vicinity of Heard Island (). The islands are Australian external territory. Prior to 1992, the volcano had not erupted in the previous 75,000 years. The McDonald Islands volcano comprises three islands: McDonald Island, Flat Island (which later merged with McDonald Island) and Meyer Rock. The islands are mostly composed of phonolitic low-silica pumice, dikes and lava domes, and sit atop a submarine plateau, the Kerguelen plateau. They are located about 75 km from Heard Island. McDonald Island is the largest
Zuidwal volcano mineral composition, points to volcanic activity as a result of subduction far away from the volcano. During the Cimmerian Orogeny, the Cimmerian Plate collided with Kazakhstania, sending shock waves through the Eurasian Plate, resulting in volcanism. The volcano is covered by layers of sandstone from the early Cretaceous that act as reservoir rock for the gas. The seal rock consists of shale. The volcanic rock is magnetic, creating a magnetic anomaly. Zuidwal volcano The Zuidwal volcano is an extinct volcano in the Netherlands at more than below ground under the Wadden Sea, between Harlingen and Vlieland, just south west of