Data Package 4 – Hydrothermal Vents
Background:
Hydrothermal vents form along ocean spreading centres and back-arc basins where seawater
percolates through the thin ocean crust to form hydrothermal fluid. Seawater becomes enriched
in sulfur and dissolved minerals (e.g. iron, zinc and copper) through reactions with superheated
rock within fractures and permeable zones in the seafloor, near the magma chamber, and is
released as superheated (250 – 400 °C) buoyant plumes of hydrothermal fluid. Once the vent
effluent mixes with the cold seawater, minerals precipitate and form black metal sulfide deposits
and tall chimneys. When the seawater does not penetrate deep enough into the ocean crust,
chemical reactions are partial and the fluid is released as diffuse flow characterized by lower
temperatures (20-50 °C). The mixing of hydrothermal fluid with seawater generates steep heat
and chemical gradients, sometimes at the scale of a few centimetres.
Vents are home to an endemic faunal community independent of energy from sunlight and
photosynthetic organisms. The vent food web fully relies on chemical fluxes as a source of
energy. Vent organisms including limpets and snails graze upon dense mats of sulphur oxidizing
bacteria, whereas suspension feeders (polychaetes and bivalves) feed on the sulphur bacteria
suspended in the water column. A common method for vent dwelling organisms to obtain
nutrients is through symbiosis with sulphur oxidizing bacteria (Lalli and Parsons, 2010).
Study Location:
1. Endeavour
Located 250 km offshore from southern Vancouver
Island, the Endeavour segment of the Juan de Fuca midocean ridge is a region of active seafloor spreading and
hydrothermal venting. New oceanic crust is formed at
Endeavour when magma emerges onto the seafloor as
lava, 2250 m’s below the ocean surface. There are five
known major vent fields at the Endeavour Segment –
Main Endeavour, Mothra, High Rise, Salty Dawg and
Sasquatch. Except for Sasquatch, all vent fields are
designated as Marine Protected Areas under Canada’s
Oceans Act (DFO, 2010).
2. NEPTUNE Canada
The NEPTUNE Canada array is the offshore component
of the Ocean Networks Canada Observatory. NEPTUNE
Canada is an 812 km cabled underwater network in the
northeastern Pacific Ocean off the west coast of
Figure 1. Bathymetric map of the five
Endeavour vent fields: Main
Endeavour, Mothra, High Rise, Salty
Dawg and Sasquatch. Image Source:
Kristall et al, 2011.
Vancouver Island. It consists of five primary locations whose instruments collect a variety of
oceanographic data. This network extends from a depth of 20 meters at Folger Passage on the
continental shelf, to a depth of 2660 meters at Cascadia Basin on the abyssal plain.
Figure 2. The Ocean Networks Canada observatory located off the coasts of Vancouver Island
and British Columbia mainland. Image credit: Ocean Networks Canada
Data Analysis:
Undersea videos collected by the remotely operated vehicle (ROV) ROPOS and the TEMPOmini camera. Environmental data from the Main Endeavour vent field are provided in this data
package. Both the videos (TEMPO-mini and ROPOS) and the provided environmental data
(BARS and RAS temperature; oxygen concentration, temperature and iron concentration from
TEMPO-mini) cover the sample time period during Sept 29 – 30 2011. These data can be used
to guide your research paper on hydrothermal vents. It is important to note that hydrothermal
vent fields have extreme temperature gradients, so a temperature reading at one point is not
representative of the entire area.
Questions:


What are the environmental conditions like at a hydrothermal vent field? (i.e. high temp,
low oxygen, scales of variability)
What types of marine organisms live in these environments? How do they adapt to such
an extreme environment?
Available Data: (note: to access the data you will need a log-in. Click
dmas.uvic.ca/Registration to obtain one)
A. Part 1: Undersea Videos Collected by ROPOS
To view video segments of the hydrothermal vents at Endeavour, follow the instructions
provided below. Note: You only need to watch the video segments indicated in Table 1. You
may need to download the Marine Field Guide to identify the species at the vents, see bottom
of this activity for download instructions.
Accessing the Data:
1. Go to the Data Portal Log-in dmas.uvic.ca/SeaTube
2. Make sure the location is set to NEPTUNE Canada (this should be the default but if it isn’t
follow this pathway: Click on the Tools tab -> navigate down to Network Preference ->
Change the Network Preference by clicking Switch to NEPTUNE Canada).
3. On the left side of the SeaTube page, you will be able to find ROPOS dive videos. Click on
the “NEPTUNE Maintenance Cruise Sept 2011”. A list of dive videos should now appear
in your window.
4. Select dive number R1488. This video is of the Endeavour hydrothermal vents and was
recorded by ROPOS during Sept 29, 2011.
5. Notice on the screen: The video player is in the centre, the map of the site is on the right, the
dives are listed on the left and the Dive Log Entries are on the bottom. The dive log entries
describe what is going on in the dive video.
Table 1. Important video segments for the dive video R1488 of the Endeavour hydrothermal
vents.
Start Date (UTC)
End Date (UTC)
Comments
03:18:21
03:22:23
03:42:22
05:14:02
03:19:43
03:28:20
03:44:19
05:15:23
08:54:56
08:56:53
10:21:09
10:25:11
10:35:51
10:36:03
Active vent with tubeworms
Active vent with tubeworms
Active vent
BARS sensor wand in hydrothermal
vent (~325 °C)
View of TEMPO-mini with
hydrothermal vent plume
Great view of vent life at TEMPO –
mini site
TEMPO-mini with hydrothermal vent
plume
6. To select the appropriate video segments, start and end dates (UTC) that are listed in Table 1
from the dive log entries
B. Part 2: Close up video clips from TEMPO-mini, located at Endeavour
To observe the hydrothermal vent marine life, the instrument TEMPO-mini records close up
video clips in addition to a variety of environmental data.
To locate these videos:
1. Navagiate to the left where the dives are listed
2. Click on the heading “Location”
3. Click on “Endeavour”, click on “Main Endeavour Field”
4. Click on TEMPO-mini
5. Click on 2011
6. Observe the close up shots on September 29th and/or 30th. There are many short clips here,
choose any to watch
7. Use Figure 3 to help you identify the vent organisms. For each organism consult the
confidence levels in the Marine Life Field Guide. If the confidence levels are low, do not record
the species name.
The Marine Life Field guide can be downloaded here:
http://www.oceannetworks.ca/science/publications/general-interest/marine-life-field-guide
Figure 3. Marine creatures viewable from TEMPO-mini, located at the Main Endeavour vent
field at Endeavour. Image credit: Ocean Networks Canada
Environmental Data
Provided are supplemental environmental data from the same time that the video was taken.
Notice the temperature, oxygen level and iron concentration. Explore the relationship between
the environmental data and the video data.
Figure 1. Temperature (°C) recorded by the remote access water sampler (RAS) at the Main Endeavour
Field during Sept. 29-30, 2011.
Figure 2. Temperature (°C) recorded by the benthic and resistivity sensor (BARS) probe at the Main
Endeavour Field during Sept. 29-30 2011.
Figure 3. Oxygen concentration [ml/l] measured from the oxygen sensor on TEMPO-mini deployed at
the Main Endeavour Field during Sept 29 – 30 2011.
Figure 3. Iron concentration [µmol/l] measured from the TEMPO-mini deployed at the Main Endeavour
Vent field during Sept 30, 2011.
References:
NEPTUNE Canada (2012). NEPTUNE Canada: An Invitation to Science. Victoria, BC:
University of Victoria.
Lalli, C. M., & Parsons, T. R. (2010). Biological Oceanography: An Introduction. (2nd ed.).
Burlington, MA: Elsevier Ltd.
DFO, 2010-2015.Endeavour Hydrothermal vents marine protected area management plan.
Retrieved from: http://www.pac.dfo-mpo.gc.ca/consultation/oceans/endeavour/docs/EHVCHE-mgmtplan-gestion-eng.pdf.
Kristall, B., Nielsen, D., Hannington, M.D., Kelley, D.S., Delaney, J.R. 2011. Chemical
microenvironments within sulfide structures from the Mothra Hydrothermal Field: Evidence
from high-resolution zoning of trace elements. 290(1-2). Pages: 12-30.
Further Reading:
Kelley, D.S., Carbotte S.M., Caress, D.W., Clague, D.A., Delaney, J.R., Gill, J.B., Hadaway,
H., Holden, J.F., Hooft, E.E.E., Kellogg, J.P., Lilley, M.D., Stoermer, M., Toomey, D.,
Weekly, R., Wilcock, W.S.D . 2012. Endeavour Segment of the Juan de Fuca Ridge, One of
the most remarkable places on earth. Oceanography. 25(1). Pages: 44-61.
Tunnicliffe, V., 1992. Hydrothermal-Vent Communities of the Deep-Sea. American
Scientist. 80 (4). Pages: 336-349.
Tunnicliffe, V., Tsurumi, M. 2003. Tubeworm-associated communities at hydrothermal vents
on the Juan de Fuca Ridge, northeast Pacific. Deep Sea Research. 50 (5). 611-629
Fowler, C.M.R., Tunnicliffe, V. 1997. Hydrothermal vent communities and plate tectonics.
21(4). 164-168.