Arago hotspot

These are structures beneath Earth's crust which generate volcanoes and which are in part formed by mantle plumes, although Arago itself might have a shallower origin.

[3] Polynesians knew of the existence of the shallow (27 metres (89 ft) beneath sea level) seamount and named it Tinomana.

The 2,200 kilometres (1,400 mi) long chain consists of two separate trends that form two atolls and eleven islands; of these systems one (Macdonald seamount) is a still active volcano.

[20] The Arago and other hotspots probably are not deep mantle plumes but rather more shallow structures that are also influenced by the lithosphere;[21] in the case of the Arago hotspot the absence of an oceanic plateau that could have been formed by the head of the mantle plume supports such a shallow origin.

[23] Data on the presence of seismic velocity anomalies and whether they are positive (higher) or negative (lower) beneath Arago are contradictory.

[30] The eponymous Arago Seamount is a composite volcano with three rift zones, similar to Rurutu.

[40] Rurutu already existed before the interaction with the Arago hotspot, having been formed by an older volcanic episode; when it moved over the Arago hotspot a volcanic episode occurred and emplaced lava flows that are formed by basanite and hawaiite.

[42] Other uplifted atolls occur northwest from Rurutu and may have formed in the same way when they passed over the Arago hotspot.

[69] A contrasting viewpoint believes that Arago is a short-lived hotspot with few dated volcanoes along its predicted path.