It is just north of the Rodrigues triple junction, approximately 2,200 kilometres (1,400 mi) east from Madagascar.

The vent field was discovered in 2000 by the R/V Kairei and ROV Kaikō operated by Japan Marine Science and Technology Center (JAMSTEC).

Fluids from the vent field have been measured in excess of 360 °C (680 °F) and are rich in metals, providing a black-smoker appearance.

[7] Carbon and nitrogen isotopes suggest that there are four distinct trophic levels at the Karei vent field.

[3] Kairei is also of concern with respect to research on deep sea dispersal pathways, with some shared biological communities to those neighboring vent fields (Edmond, Solitaire, DoDo).