Deep-Sea Hydrothermal Systems

Global Distribution of Hydrothermal Fields

Global Hydrothermal Vent Distribution

Global Distribution of Hydrothermal Vents - InterRidge 2009

Worldwide distribution of known hydrothermal vent fields (InterRidge 2009)

Portuguese Hydrothermal Fields

Portuguese Deep-sea Hydrothermal Fields

Hydrothermal vent fields discovered on the Portuguese seafloor

Moytirra Hydrothermal Field (45°28′N, 27°50′W; ~2900 m)

Max temperatures: ~270 °C

Setting: Basaltic MOR system at the slow-spreading Reykjanes Ridge, hosted within a volcanic rift valley.

Luso Hydrothermal Field (~39°00′N, 29°88′W; ~570 m)

Max temperatures: not yet measured

Setting: Basalt-hosted vent field on the Menez Gwen segment, associated with recent volcanic activity in the Azores region.

Menez Gwen Hydrothermal Field (37°84′N, 31°52′W; ~865 m)

Max temperatures: ~285 °C

Setting: E-MORB basalt-hosted field located at the summit caldera of a young axial volcano, with focused black-smoker venting.

Lucky Strike Hydrothermal Field (37°29′N, 32°27′W; ~1600–1725 m)

Max temperatures: ~333 °C

Setting: E-MORB basalt-hosted field situated within a central volcano caldera on the axial graben of the MAR.

Menez Hom Hydrothermal Field (37°15′N, 32°43′W; ~1800 m)

Max temperatures: <10 °C

Setting: Ultramafic-hosted, low-temperature diffuse venting site with strong CH₄ discharge, located near a non-transform offset.

Saldanha Massif Hydrothermal Field (36°56′N, 33°43′W; ~2200–2300 m)

Max temperatures: ~9 °C

Setting: Ultramafic-influenced diffuse field on a non-volcanic ridge massif, characterized by serpentinized peridotites and a tectonic mélange.

Rainbow Hydrothermal Field (36°23′N, 33°90′W; ~2320 m)

Max temperatures: ~365 °C

Setting: Ultramafic-hosted black-smoker system, extremely rich in H₂ and CH₄, located on the western flank of a non-transform offset between the AMAR ridge segments.