The International District Vent Field 1 Medium-Power Jbox supports instruments to investigate the chemistry and temperatures of high temperature and diffuse flow vent sites within the International District Hydrothermal Field located along the eastern rift zone of Axial Seamount at a water depth of ~1520 m. The main study sites include the actively venting chimneys called El Gordo, Escargot, and Diva. The El Gordo site also hosts a digital still camera and microbial DNA sampler. Coupled with the geophysical array on the summit of Axial Seamount, these instruments are designed to better understand linkages between seismicity, fluid temperatures and chemistry, and the evolution of biological communities over time in highly dynamic environment commonly perturbed by volcanic eruptions.

Instruments are attached to a Medium-Power J-Box and are mounted on/near the seafloor and on a cabled mooring (e.g fluid and DNA sampler). Axial Seamount on the Juan de Fuca spreading center is an optimal site for a long-term observatory. Not only is it just one day by ship from the Washington and Oregon coasts, but it is the most magmatically robust volcano on the spreading center. Additionally, its caldera hosts numerous active hydrothermal fields and abundant sites of diffuse flow.  The International District 1 site monitors one of these hydrothermal vent fields.

Seafloor instruments at the ASHES site are attached to a Medium-Power J-Box (MJ03C) through a series of extension cables. An ~ 2.2 km long extension cable from Primary Node PN3B provides the JBox with significant power (375 v) and bandwidth (1 Gbs) to operate the instruments and transmit data to shore.


This site includes following instruments. To learn more about an instrument type, select its name on the left. To see the relevant data streams for a particular instrument, select the instrument code in the first column which will take you to the OOI Data Portal.

Instrument Depth Node Instrument
Make & Model
RS03INT1-MJ03C-05-CAMDSB303 1,520m Medium-Power JBox (MJ03C) Digital Still Camera (CAMDSB) Kongsberg - Custom Digital Still Camera Assembly
RS03INT1-MJ03C-09-THSPHA301 1,520m Medium-Power JBox (MJ03C) Hydrothermal Vent Fluid In-situ Chemistry (THSPHA) Kang/Seyfried, U Minnesota - Vent Chemistry Instrument (H2, H2S, pH)
RS03INT1-MJ03C-07-RASFLA301 1,520m Medium-Power JBox (MJ03C) Hydrothermal Vent Fluid Interactive Sampler (RASFLA) PMEL/Butterfield - Modified McLane Remote Access Sampler
RS03INT1-MJ03C-10-TRHPHA301 1,520m Medium-Power JBox (MJ03C) Hydrothermal Vent Fluid Temperature and Resistivity (TRHPHA) Lilley, UW - Vent Temperature & Resistivity
RS03INT1-MJ03C-06-MASSPA301 1,520m Medium-Power JBox (MJ03C) Mass Spectrometer (MASSPA) Girguis, Harvard - cabled Mass Spec
RS03INT1-MJ03C-07-PPSDNA301 1,520m Medium-Power JBox (MJ03C) Particulate DNA Sampler (PPSDNA) PMEL/Butterfield - modified McLane Particulate Sampler