Hawaii hotspot
Hawaiian volcanoes are characterized by frequent rift eruptions, their large size (thousands of cubic kilometers in volume), and their rough, decentralized shape. Rift zones are a prominent feature on these volcanoes, and account for their seemingly random volcanic structure. The tallest mountain in the Hawaii chain, Mauna Kea, rises above mean sea level. Measured from its base on the seafloor, it is the world's tallest mountain, at ; Mount Everest rises above sea level. Hawaii is surrounded by a myriad of seamounts; however, they were found to be unconnected to the hotspot and its volcanism. Kīlauea has erupted continuously since 1983 through Puʻu ʻŌʻō, a minor volcanic cone, which has become an attraction for volcanologists and tourists alike.
Hauhungatahi
Hauhungatahi is an eroded volcano at the southern end of the Taupo Volcanic Zone in New Zealand, located about WNW of Mount Ruapehu. Although relatively little-known, at Hauhungatahi is one of the highest volcanoes in New Zealand, exceeded in elevation by only Ruapehu, Taranaki/Egmont (including Fanthams Peak), and the Tongariro massif (including Ngauruhoe). The volcano is constructed atop an upfaulted block of Mesozoic marine sediments. The age of the erupted andesite lava is about 900,000 years, making Hauhungatahi more than three times as old as the neighboring Ruapehu.