Latest TCS News
- (August 10, 2011)
Eruption at Axial Volcano
"Scientists Discover New Eruption at Undersea Volcano," Environmental protection online, Aug. 10, 2011
"Surprise Underwater Volcanic Eruption Discovered," LiveScience, 9 August 2011 (includes video clip)
"Surprise! Underwater volcano has erupted: Scientists going back to pick up monitoring equipment find a changed seafloor," MSNBC, 9 August 2011
- (March 15, 2010)
Earthquake swarms - East Blanco Depression
Over the last four days there has been an exceptionally large number of earthquakes occurring along the western Blanco Transform, within the East Blanco Depression.
The diagrams above show the SOSUS locations (red dots) and the USGS locations of the largest earthquakes in the sequence (white stars). The SOSUS locations are distributed along the transform, but generally are centered along the eastern side of the E. Blanco pull-apart basin. The histogram shows the number of earthquakes were able to be counted from the hydrophone data, with 1000+ events occurring since last Friday.
The location of these East Blanco events is ~50 km southwest of the intraplate swarm detected in 2008. The earthquake swarm in 1994 that lead to the mapping of pillow-lava mounds and barite chimneys was centered on the west side of this basin.
The swarm is still going, and updates will be posted with anything significant from the SOSUS data side.
- (September 18, 2009)
ERUPTIONS IN THE NE LAU BASIN
Link to video clips of West Mata Submarine Volcano eruption on NOAA Vents webiste.
NE Lau Response Team: J. Resing, R. Embley, K. Rubin, E. Baker, J. Lupton, M Lilley, T. Shank, R. Dziak, T. Collasius (Jason 2 Expedition Leader), N. Buck, T. Baumberger, D. Butterfield, , D. Caress, D. Clague, D. Conlin, J. Cowen, R. Davis, L. Evans, J. Huber, M. Keith, N. Keller S. Merle, P. Michael, E. Podowski, A.-L. Resysenbach, K. Roe, T. Shank, H. Thomas, S. Walker
An active boninitic eruption was observed at West Mata (Figure 1) submarine volcano in the NE Lau basin in May 2009. West Mata volcano is the largest in a series of en echelon volcanoes lying between the magmatic arc front and the NE Lau spreading center. The eruption was witnessed during an eruption-response cruise to examine the sites of two eruptions in the NE Lau Basin that were discovered in November 2008 during a NOAA- Pacific Marine Environmental Laboratory expedition on the R/V T. G. Thompson. The second of the two eruptions was along the NE Lau Spreading Center (NELSC) and was not actively erupting during the response cruise. During the response cruise five ROV dives were conducted at West Mata Volcano and two at the NELSC to characterize the volcanic deposits and associated phenomena.
The expedition was a success on multiple fronts. We collected 22 biological, 69 fluid, 15 gas and 68 rock and/or clastic samples from two sites of ongoing or recent submarine volcanic activity. The rocks included rare boninite lavas. The NELSC and West Mata eruptions will provide insight on the long-term history of a back-arc rift zone, with the West Mata site representing a proto-backarc system (young rifted crust) and the NELSC site the established backarc spreading system. The on-going eruption at West Mata is only the second active submarine eruption witnessed to date and the observations and samples collected will provide important understanding on the relation ship between neo-volcanic processes and hydrothermal activity. At the NELSC, however, aside from the fresh lava flows and volcanic debris, ROV dives and CTD tows provided no evidence of new and/or enhanced hydrothermal activity along the ridge. The absence of an extant hydrothermal system along this part of the ridge and the apparent absence of a recently reset hydrothermal system precluded the study of the chemical and biological evolution following an eruption and greatly reduced the potential use of this segment of the NELSC as a comparison site for the R2K East Lau Spreading Center (ELSC) Integrated Study Site (ISS). Although biological and hydrothermal samples were collected at a low temperature site located on older flows a more relevant regional comparison to the ELSC-ISS would be to sample a high temperature site. As a result the ROV transited 3km southward along the NELSC to Maka Volcano, where high temperature black smokers had previously been found by Nautilus Minerals. This site was situated upon a large mound of sulfides and was host to a wide range of biological activity. The site was sampled for rocks, biology, fluids, and sulfides and should provide regional context and contrast to findings at the Lau ISS.
Responses to volcanic events on the Juan de Fuca and Gorda Ridges and the East Pacific Rise during the past two decades have resulted in many new insights on chemical, biological, and geological processes. The observations made as a part of this rapid response effort continue this effort, providing new and fundamental insights on eruptive phenomena in the deep sea. The eruption at the NE Lau spreading center is the first ever observation of an eruption along a back arc spreading center, while the eruption at West Mata was the first ever observation of an active boninitic eruption. Zero-age samples of boninite (a rare, water-rich magma type believed to form from slab-derived fluid fluxing of shallow refractory mantle) were collected for petrological and geochemical studies. Such investigations, and geochemical studies of associated magmatic/hydrothermal fluids, will improve our understanding of material and energy fluxes through subduction zones. Biological studies will provide information about seafloor colonization during and just after an eruption. Finally, analysis of video and acoustic data will enhance our understanding of deep-sea eruption processes.
Acknowledgements
The response effort was funded by NSF (R2k and Margins and NOAA (Ocean Exploration and Research and PMEL-Vents). The interaction between Ridge2000, MARGINS, and NOAA-Vents scientists has been very rewarding.
- (September 5, 2009)
The science report from the Ridge 2000/MARGINS/NOAA-OE-sponsored NE Lau Basin Eruption Response Cruise (5-13 May 2009) is available for download: NELRC Cruise Report (32.2 MB pdf)
- (May 1, 2009)
Updates and preliminary findings from the Ridge 2000/MARGINS/NOAA-OE-sponsored NE Lau Basin Eruption Response Cruise (5-13 May), led by Chief Scientist, Joe Resing, will be posted on this website: http://laueruptions.blogspot.com.
- (February 5, 2009)
Announcement distributed to R2K, MARGINS and UNOLS email lists:
Introduction:
The Ridge 2000 (R2K) and MARGINS Programs Steering Committees, in conjunction with NSF and NOAA program managers announce an eruption response cruise to the Northern Lau Basin. These groups have reviewed preliminary shipboard data and participated in numerous teleconferences and email correspondences over the past month to discuss opportunities for a response to recently detected volcanic eruptions in the northern Lau Basin [Shipboard Science group Lupton, Resing et al]. Based on these deliberations, NSF has agreed to fund an event response cruise to be led by Dr. Joe Resing (U. Washington & NOAA PMEL) in May 2009 to collect time-critical samples and make observations. The cruise will involve the R/V Thompson and the ROV Jason 2 system. The purpose of this announcement is to provide basic background information to the scientific community, and to solicit short letters of interest from investigators who wish to participate in the cruise (i.e., sample collection or analysis) and/or collaborate through shore-based efforts. Letters can be submitted by email to the R2K or MARGINS office, as described below.
Solicitation of Interest From Ridge 2000 and MARGINS Investigators:
The nature of the response effort dictates that there be a focused field and laboratory effort that is directed towards time-critical studies, including sample collection, field observations, and shipboard and shore-based analyses. We expect that the ship, ROV facilities, time, and the costs to send a science team into the field for this work will be funded jointly by NSF R2K, MARGINS, NOAA-PMEL and NOAA-Ocean Exploration. The ~9 day cruise will likely occur from May 5-13, 2009.
Dr. Resing, in collaboration with the Executive Committees of the Ridge 2000 and MARGINS Programs, and the staff of the NOAA VENTS Program are developing a scientific plan and discussing personnel staffing for the shipboard operations during the response cruise.
Scientists interested in shipboard participation or shore-based collaborations associated with the event response are encouraged to contact the Ridge 2000 and MARGINS Offices at: ridge2000@whoi.edu and abers@nsf-margins.org. Short Letters of Interest (1 page maximum), emailed to BOTH addresses indicated above, should be received no later than February 13, 2009, to facilitate planning for the upcoming cruise. Please be sure to provide information about what you can contribute to the response effort, whether you need to participate in the cruise, what you would like to do with samples or data from the cruise, and whether that can be done with your existing funding.
Dr. Resing and the science team that discovered the eruptions last year are involved in discussions with program managers at NSF and NOAA to develop a proposal and funding plan to cover the immediate field costs. Modest proposals to help fund science costs related to this event response effort are currently under discussion with by NSF and NOAA program managers. Letters of interest received from the community will be used to help develop the science plan and assess participation by other scientists who have interests in this area.
Data resulting from the response cruise will be made available to the scientific community quickly, with daily updates from the ship during the cruise and other preliminary data compiled within a few months of the end of the cruise. Some of the time critical analyses, including Po-dating of lavas will take longer because of analytical requirements. Brief statements of interest for ancillary/follow-up studies lacking a critical time component are also welcome and will be accommodated if sufficient samples/observations are available to support them. Please send inquiries or requests for information to the email addresses listed above.
A PDF file containing some preliminary findings from the North Lau Eruption sites is available.
- (November 21, 2008)
From:
John Lupton, Chief Scientist - Voyage TN227 of the R/V Thompson
Ed Baker
Robert Embley
Joseph Resing
Marvin Lilley
Voyage TN227 of the R/V Thompson is presently conducting seafloor mapping and water-column plume surveys in the NE Lau region. We are currently over the NE Lau Spreading Center at ~15° 24' S, 174° 15' W. We have found that the water column over this back-arc spreading center is populated with an unusual suite of spectacular plumes at depths ranging from 1400 m up to 700 m below the sea surface. Some of our water column profiles detected over 5 distinct hydrothermal plume layers, and the shallowest of these plumes is over 600 m above any local topography. Furthermore the plumes are characterized by intense light scattering anomalies, high Eh signals, and in some cases very high concentrations of dissolved hydrogen. This represents a considerable increase in activity compared to the previous study conducted here on the R/V Kilo Moana in 2004 [German et al., g-cubed, 2006], and a suite of plume surveys conducted using IMI30 and MAPRs in July 2008. Based on our collective experience, these plumes have the physical and chemical characteristics associated with seafloor eruptive activity. During the remaining 6 days of this expedition, we plan to continue surveying the region and attempt to localize the source of this unusual activity. We had considered deploying Dan Fornari's camera system, which is also on board, but not all of the necessary components are on the ship. We believe the RIDGE community should consider this site as a focus for future Time Critical Studies activities, especially in conjunction with ship operations supporting the Lau ISS.
- (April 29, 2008) A large earthquake
swarm began April 22, 2008 on the northern segment of the
Gorda Ridge. This event continued April 23, 2008 but was
tapering off quite a bit. The response cruise aboard R/V Wecoma
obtained 2 CTD casts at Gorda on the way into port. Shipboard
analyses did not suggest a plume but onshore analyses are
required before such occurrence can be ruled out. Updates
will be available.
An intense Juan de Fuca plate
earthquake swarm (3/30/08 – 4/9/08) subsequently decreased and
later earthquakes shifted from the intraplate area to Blanco
fracture zone (mainly cascade depression and Blanco Ridge).
A short response cruise (4/20/08 – 4/24/08) obtained a series of CTD
casts to assess potential water column expressions associated
with the earthquakes.
For more information on the
response cruise, please visit the PMEL event
response page
- (April 21, 2008) The intense Juan de Fuca plate earthquake
swarm (3/30/08–4/9/08) has now decreased and recent earthquakes
have locations that are shifted from the intraplate area to
Blanco fracture zone (mainly cascade depression and Blanco Ridge)
(view seismicity map). A short response cruise from April 20
– 23, 2008 is investigating potential water column expressions
associated with the earthquake swarm.
- (March 30, 2008) On Sunday March 30, 2008, a large
earthquake swarm began within the central Juan de Fuca
plate, located ~150 nautical miles west of the Oregon
coast and ~ 70 km north of the Blanco Transform Fault
(enclosed map). This earthquake swarm (with red, yellow,
brown, purple dots representing different days) is located
on a basin between two faulted basement highs that rise
above the surrounding, deep abyssal sediments. The
swarm, located using the SOSUS hydrophone arrays,
has produced more than 600 earthquakes in the past 10
days. This earthquake swarm is unique since it is the
first time in 17 years of SOSUS recordings that a set
of earthquakes this focused and intense has occurred
within the middle of the Juan de Fuca plate away from
the major, regional tectonic boundaries. The abyssal
hill nearest the swarm location appears to be on a
curved structure that trends northwestward from the
Cascadia Depression in the BTFZ toward the Juan de Fuca
Ridge. However, seismicity decay rates indicate this is
not a standard mainshock-aftershock sequence and some
process is sustaining a high stress rate in the crust
(Figure
2).
Given the midplate location of the swarm, a volcanic event response
effort does not seem warranted. However, this situation represents a rare
opportunity to learn more about this very unusual event. Accordingly,
we are exploring options for ships-of-opportunity that might be able to
take some key samples and measurements with a CTD over the earthquake
swarm site with a minimum of time and effort.
- (November 22, 2007) Using SOSUS,
we detected a small swarm of 5 earthquakes centered on
a seamount along the west flank of the Cobb segment of
the Juan de Fuca Ridge (View map, general earthquake
locations shown with star). The swarm began at 1400Z on
22 November 2007 and lasted for 1 hour. Given the small
number of earthquakes, a response cruise is certainly not
warranted, however it is interesting from the standpoint
that this part of the Cobb segment continues to exhibit
a steady, low-level amount of seismicity.
View
map, general earthquake locations shown with star
- (August 1, 2007) There
has been a progression of earthquakes beginning at the
Northern Gorda, moving to the eastern then western Blanco
Transform, and ending at the Cleft-Vance intersection at
the southern Juan de Fuca Ridge. This past week of
earthquake activity recorded by SOSUS contrasts with low
levels of activity that characterized the prior three
months. The recent plate boundary sequence began on
July 18 at 2014Z with a large earthquake that occurred
in the central valley of the northern Gorda Ridge which
was followed by 20 aftershocks.
- (July 24, 2006) Review sequence of findings
and response cruise efforts for East Pacific Rise 9°50'N
2005-2006 eruption
- Swarm
Fan email list to distribute information about
the real-time detection of moderate-sized earthquake
swarms and tectonic events on the Juan de Fuca Ridge
or other evidence of spreading center activity that R2K
is following.
- See the TCS news
archive for previous TCS news and updates.
