On the second voyage of the Beagle, in the 1830s, Darwin had theorised that as land rose, oceanic islands sank, and coral reefs round them grew to form atolls.

It was dredged and surveyed in 1968 by the ship R/V Alexander Agassiz;[3] previously in the same year the R/V Argo had crossed over the guyot.

[6] This 18 metres (59 ft) deep[10] depression may be a volcanic crater but the more likely explanation is that the rim was formed by living organisms.

[1] Dredging has yielded no volcanic material, but chert, limestones (in the form of grainstone, packstone and wackestone[12]) encrusted with ferromanganese as well as living animals were pulled up.

[13] The seafloor underneath the guyot lies at a depth of 5,250 metres (17,220 ft)[1] and has an age of 157 million years.

[19] Rudists formed organic frameworks resembling coral reefs on Darwin Guyot and elsewhere in Tethyan seas during the Albian-Aptian eras.