Hot hydrothermal fluids are frequently observed emanating from small orifices on the tops and sides of hydrothermal vent structures. The hot fluids are highly localized, and ambient seafloor temperatures (~2 degrees Celsius) are common within a few centimeters of active orifices.
Species (common):
Year: 2004
Details:
Media Type: Photograph
Data Type: Photograph
Device Type: Camera:Digital
Feature: EPR:9N:Tica
Investigator: Vicki Ferrini
Expedition: AT11-20
Chief Scientist: Marvin Lilley
Species: Riftia pachyptila (Tube worm) Bathymodiolus thermophilus

The base of a hydrothermal vent structure located within an area of diffuse flow. Consistent focused flow of hot hydrothermal fluids can result in the formation of hydrothermal vent structures that are formed as metal rich fluids result in hydrothermal deposits rich in minerals like sulfur, copper, zinc, gold, and iron. Hydrothermal structures can grow to be several meters in height and width.
Species (common):
Year: 2004
Details:
Media Type: Photograph
Data Type: Photograph
Device Type: Camera:Digital
Feature: EPR:9N:Tica
Investigator: Vicki Ferrini
Expedition: AT11-20

At mid-ocean ridges like the East Pacific Rise (EPR), collapse features are common along the axis of the spreading center. Cracks and collapse features can help with the mixing of cool seawater with hot hydrothermal fluids, and also provide pathways for warm water to escape from the seafloor resulting in conditions optimal for specialized organisms like these.
Species (common):
Year: 2004
Details:
Media Type: Photograph
Data Type: Photograph
Device Type: Camera:Digital
Feature: EPR:9N:Tica
Investigator: Vicki Ferrini
Expedition: AT11-20
Chief Scientist: Marvin Lilley

Wall of the Axial Summit Trough (AST) of the East Pacific Rise. The layers shown here are due to the emplacement of lava during repeat eruptions at this site. The fractured wall is due to collapse along the AST as lava recedes into the eruptive fissure of the AST.
Species (common):
Year: 2004
Details:
Media Type: Photograph
Data Type: Photograph
Device Type: Camera:Digital
Feature: EPR:9N
Investigator: Vicki Ferrini
Expedition: AT11-20
Chief Scientist: Marvin Lilley
Species: Munidopsis subsquamosa

Lobate lava on the East Pacific Rise. These formations are common along the flanks of the spreading center and are put in place during volcanic eruptions.
Species (common):
Year: 2004
Details:
Media Type: Photograph
Data Type: Photograph
Device Type: Camera:Digital
Feature: EPR:9N
Investigator: Vicki Ferrini
Expedition: AT11-20
Chief Scientist: Marvin Lilley
Species:

Mosaic of the Twin Peaks hydrothermal cluster, which includes two ~8m tall sulfide structures called the Climber (left) and Flying Buttress (right). These comprise the most actively venting portion of the cluster. Smaller extinct sulfide chimneys surround the active structures, with localized areas of diffuse flow emanating from the sulfide talus at the base of the chimneys. This mosaic includes 17 images collected on Jason dive 231 during the 1997 Edifice Rex cruise. Photo mosaic created by Mitchell Elend, University of Washington.

Caption from the Smithsonian Global Volcanism Project: Conical Volcan Arenal is the youngest stratovolcano in Costa Rica and one of its most active. The 1670-m-high andesitic volcano towers above the eastern shores of Lake Arenal, which has been enlarged by a hydroelectric project. Arenal lies along a volcanic chain that has migrated to the NW from the late-Pleistocene Los Perdidos lava domes through the Pleistocene-to-Holocene Chato volcano, which contains a 500-m-wide, lake-filled summit crater.

Located 520 kilometers (323 miles) north of Saipan, Maug is actually three islands that were once part of the rim of a volcano now partially submerged. Where the volcano cone was is now a deep and spacious natural harbor. Steep cliffs border the islands and the landscape on the north and west islands is dominated by columns of basalt resembling tombstones. Highest point North Island, 227 meters (746 feet). Size: 2 square kilometers (0.8 square miles). Uninhabited.

Located 586 kilometers (364 miles) north of Saipan, the island has an active volcano which keeps its steep slopes smooth by frequent flows of lava and ash. The summit is crowned with white sulfur and at times dense clouds of yellow smoke and fire issue from the crater. The southwest and west shores are precipitous and bare. Highest point 319 meters (1,047 feet). Size: 2.6 square kilometers (1 square mile). Uninhabited. For an example of studies on these IBM volcanoes, see Shaw et al., 2008.
Species (common):

The east face of the Faulty Towers hydrothermal cluster comprises the largest cockscomb array known in the Mothra Field. Seventy-three electronic still images from Jason dive 229 were used to create this mosaic.
Species (common):
Year: 1997
Details:
Media Type: Photomosaic
Data Type: Photograph:Mosaic
Device Type: Camera:Digital
Feature: JdF:Endeavour:Mothra:FaultyTowers
Investigator: Deborah Kelley
Expedition: AT03-07
Chief Scientist: John Delaney
Species: