Samoa hotspot

[3] As the Pacific Plate moves slowly over the hotspot, thermal activity builds up and is released in magma plume spewing through the Earth's crust, forming each island in a chain.

[7] This has been postulated to be due to enhanced rejuvenated volcanism associated with the close proximity to the northern Tonga Trench, which is just over 100 km (62 mi) south of the westernmost Samoan island of Savai’i.

[8] In 1975, geophysicist Rockne Johnson discovered the Vailuluʻu Seamount, 45 km east of Taʻū island in American Samoa which has since been studied by an international team of scientists and characterised as the youngest voclano of the Samonian hotspot chain.

[9] The postulated rejuvenated volcanism in Samoa associated with the close proximity to the northern Tonga Trench has now been extended to the Papatua Seamount, 60 km (37 mi) south of the axis of the Samoan hotspot track.

[10] Combined with the data from Uo Mamae seamount, it seems possible that flexural uplift in the Pacific Plate near the northern terminus of the Tonga Trench has resulted in melting of Samoan plume material that has erupted recently.

[13] Subducted Samoan mantle material has also been found erupted in the northern Tonga arc between 280 to 300 km (170 to 190 mi) to the south at Tafahi and Niuatoputapu, and in some lavas in the north western Lau basin.