Mid-Ocean Ridge Observatories- OOI Priorities
Thank you for your participation in this online discussion! Your comments on key science that could be achieved at an observatory on the East Pacific Rise (9N) versus on the Mid-Atlantic Ridge (MoMAR) were an important part of Steering Committee considerations for the revised recommendation. That document R2K OOI recommendation was provided to the Global STAC on Monday, May 1.
April 18 Draft Recommendation. Additional info at April4 email.
All 3 mid-ocean ridge observatory conceptual proposals are available for download via the following link (listed by lead PI: for EPR- Tolstoy; for Juan de Fuca- Wilcock; for MAR- Humphris. OOI RFA Proposals
March 16th, 2006 at 8:56 am
Chris German, WHOI:
In terms of science I would be interested in doing inside *any* observatory - I could see real merit (and feasibility) in deploying sediment traps and/or in situ filtration devices that could collect samples determining long-term variiability in plume output from any given site, most usefully if deployed within some system that lso monitored physical flow at and around said site. What could be done with an observatory is that, as well as having a default setting to change sample collectors every 2 weeks or so, one could also build in the potential to respond to any “event” and carry out higher resolution - e.g. daily - sample changes to look at any immediate post-eruption in changes in the nature (chemical composition, bacteria vs mineral grains) as well as quantity of flux following such an event. The “missing” flux associated with Events has been alluded to often but remains completely unquantified in terms of its significance to the total output from any vent over its full life-cycle. The other neat thing about such traps (with pumps presumably also triggerable in response to events?) is that they allow one to do a suite of inorganic chemical, organic chemical, microbial and “macro”-biological studies on the same samples, nested within a physical oceanographic array and co-registered with any seafloor geophysical (e.g. micro-seismic) and geochemical (fluid composition, temperature) variations.
March 16th, 2006 at 3:46 pm
Peter Girguis, Harvard:
I second Chris’ comments. There are a suite of other instruments we could consider as well, but I think the key point here is that an observatory could…if developed appropriately…go a long way towards improving our undertanding of events. I’ve many more thoughts on this matter, but I’ll hold off until others ptitch in….
March 17th, 2006 at 8:22 am
Javier Escartin, CNRS France, Chair InterRidge MOMAR Steering Committee:
The Lucky Strike is the target of an active French research program for long-term seafloor observations and monitoring (MOMAR France, www.momarfr.org, & also www.momar.org). France is also heavily involved in a EU program, ESONET (www.esonet.org), to establish a network of seafloor observatories, including one at the Lucky Strike site. These and many prior projects ensure ongoing participation of EU scientists at the MOMAR site, following up on the heavy involvement of the last decade or more. There are currently several active field projects and numerous proposals for research at Lucky Strike. Furthermore, the University of Azores and LabHorta have facilities and a vessel that may be used to recover/deploy instrumentation. In addition, owing to the classification of the Azores as a ‘peripheral’ region by the EU, any international scientific activity that may be based in the area will most likely have a very strong support.
There is an active proposal in the EU to establish the ESONET observatory network, requesting 7 MâŹ. There will be ~4 M⏠for implementation of test observatories, that will fund the infrastructure of a few of the nodes within ESONET. The choice of test sites will be done on the basis of proposals, and Lucky Strike will be one of them (before the end of 2006). If successful, this may provide funding at the level of ~1M⏠for an autonomous observatory at the site, earlier than 2008. This would fund an autonomous site with a simple buoy and telemetry (i.e., no power to the seafloor). We expect to have a full proposal to extend this exploratory/test phase by the end of â08, with implementation byâ09.
If ORION chooses Lucky Strike there will be a need to have compatible instrumentation, data protocols, connections, etc (IFREMER is already involved with ORION in this aspect - R. Person, the coordinator of ESONET, will attend the ORION meeting). It is thus a good place for international cooperation at a level that will not be available at the EPR; EU scientists involved in MOMAR will not shift as a community to another site, including the EPR, which may be seen as a US-only site, mostly due to access problems by the fleet, and by the existing science programs and funding.
Interest by individual scientists on the EPR definitely exist, but I cannot identify a clear EU community effort in this direction. Initiatives coordinated at national and international levels exist elsewhere, including Arctic ridges (led by Nordic countries) and the southern Atlantic (led by part of the German community).
Useful links:
MOMAR www.momar.org
MOMAR France www.momarfr.org
ESONET: http://www.oceanlab.abdn.ac.uk/research/esonet.shtml
MOMARNET: http://www.momarnet.org
EXOCET/D: http://www.ifremer.fr/exocetd/
March 20th, 2006 at 8:50 am
Andreas Teske, UNC, Chapple Hill:
To get an idea of microbial community dynamics and the pace of change during/after an eruption, real-time chemical and visual monitoring has to be complemented with sample retrieval for cultivation and sequencing.
Means to recognize/define an event:
— Changes to macrofaunal communities are best monitored visually. They can be quite abrupt, as the consequence of a single dramatic eruption, but they can also occur over several years at a slow rate - for example, if the chemistry or redox state of a vent field slowly changes. A text book example (with amazing pictures) is the evolution of Riftia communities at 9N EPR (Shanks et al. 1998. Deep Sea Research II 45, pp. 465-515). — Microbial community changes are often not as obvious; although some vent bacteria can form conspicuous blobs of biomass in a short time. To monitor event- related microbial community dynamics, water column, vent fluid, rock and sediment samples have to be retrieved for cultivation and sequencing, and, as much as possible, correlated with physical/ geochemical changes.
Possible response to recognized event
— The microbial community will respond to the event very quickly. Within a few days or one or two weeks, new types of bacteria and archaea will appear in the water column and colonize solid substrates, and use the freshly available vent fluid chemicals (dissolved inorganic electron donors and gases) as well as temporary sources of organic biomass (barbecued Riftia stands). An event-response cruise should take some water samples of the vent plume as well as solid substrates for sequencing. Based on colonization experiments with growth chambers and experimental substrates, models of microbial community succession at hydrothermal vents have been developed (which archaea and bacteria develop first, second, third etc after a vent eruption) that remain to be tested during actual vent eruptions.
Provision of power to the seafloor enables experiments that are
— A conceptually simple and useful observation tool on the seafloor would be an in-situ digital camera (with a strong flash) that takes pictures of a vent field every day, and stores them until retrieval. I am planning such experiments in a different context in the Gulf of Mexico, at 900 m depth. Having eyes at the vent would benefit different experiments where chemical and physical parameters are monitored; one would know with much greater certainty what actually happened at the time of a suspicious data peak. To my knowledge, such cameras require batteries that last several weeks or even 2-3 months, but not longer. Power on the seafloor would certainly help.
March 21st, 2006 at 3:08 pm
Joe Resing UW-PMEL
I suggest that the EPR ISS is a more attractive site than the MAR. I make this suggestion because I believe that the hydrothermal system at the EPR is likely to exhibit more change over time than that at the MAR. These changes are manifest in hydrothermal output and chemistry over the last fifteen years at the EPR. Also, based on one known and one suspected eruption in the last 15 years, I think that the EPR is more likely to experience a magmatic event over the life time of a mooring than a mooring at the MAR. Finally, the ISS at the MAR will not be in place prior to the proposed mooring emplacement, while that at the EPR will have been in operation for approximately five years. This means that there will be sufficient data available to put mooring data in context.
March 21st, 2006 at 3:23 pm
Joe Resing UW-PMEL
The research that I would be interested in doing is based on my experiences with the NEMO moored observatory. I would be interested in using profiling moorings instrumented with simple low-power instruments like optical backscatter, temperature, and Eh. These moorings would provide depth profiles of particles, water temperature, and Eh. A profiling instrument is essential because plume direction, height, and thickness respond to tidal currents, long time period current fluctuations, and hydrothermal output and events. The results of the profiles will be essential to place the measurements from the statically placed instruments in perspective (see Chris Germanâs discussion above). In addition to the almost solid state sensors listed above, I would hope to develop other sensors to be deployed both on profiling moorings and on static moorings.
March 21st, 2006 at 4:04 pm
Javier’s comments make it clear that studies at the Lucky Strike area are well under way and thriving. My own experience is that the groups working there (Javier in particular!) have been very welcoming to other groups seeking to work there. However, scientifically the strong leadership from the Europeans at this site means that we will have many interesting insights coming from Lucky Strike with or without involvement of an OOI buoy. So to maximize scientific return it would be more valuable to put the buoy at the EPR, and in that way the global ridge community will be monitoring slow, intermediate and fast spreading ridges.
The essence of real-time monitoring and response capabilities is to interact with a dynamic environment. A fast spreading ridge, particularly a site as well studied as 9-50 EPR, provides the maximum likelihood of capturing an eruptive event, which is what would provide the biggest conceptual leaps in our understanding of ridge processes. On-going multidisciplinary monitoring at the EPR combined with monitoring from the previous decade+ shows that this site exhibits significant changes on the monthly-yearly time scales, (as per Joe’s comments above) and is a highly dynamic environment. We have a time series baseline stretching back to the 1991 eruption. It would be a shame if we finally were able to establish real-time interactive monitoring of a mid-ocean ridge and we didn’t monitor a fast spreading ridge, particularly the most dynamic, active, and well base-lined site we have.
March 22nd, 2006 at 2:39 pm
Ken Macdonald, UCSB:
I strongly agree with Joe Riesing’s and Maya Tolstoy’s comments on the site.
9N has a >15 year time series to build upon. This is truly unique and too
important to pass up. The rates of change are known to be rapid, there have
been already at least two eruptions. Significant changes in the
hydrothermal system have been documented by Von Damm, Fornari, Sohn, Haymon,
Lutz, Shank and others over short time scales. It is critical to our
knowledge of linkages between tectonic, magmatic, volcanic, hydrothermal and
biological processes to continue this time series.
The enormous advantage of an Orion buoy system is the continuity of
monitoring. I am sure we have missed many important events resulting in
important gaps in our time series of the interacting components of the
system. An Orion buoy network would solve this big problem. I am also
hopeful that some part of the buoyed local area network might reach a bit
off-axis to areas I find interesting for volcanic, tectonic and hydrothermal
studies.
I am fully sympathetic with the Mid-Atlantic Ridge studies at MOMAR, hey,
its right at the edge of my PhD thesis area, gotta love it! But…. the
rates of change are likely to be slow. To a first order, many of the events
which concern us scale with spreading rate; for example, dike intrusions
which fuel hydrothermal activity, trigger earthquake swarms, and have
important effects on geochemistry and faunal communities. The MOMAR site
will be almost an order of magnitude slower/less frequent than the EPR ISS.
If Perfit and Chadwick 1998 are correct, the contrast in eruption frequency
is even greater. In their fig 24 they estimate the eruption frequency to be
once every ~10,000 yrs for spreading rates in the MOMAR area and less than
every ~5 years for spreading rates corresponding to EPR 9N. Granted these
are very approximate estimates, but few would argue that the rates of change
and utility of a real time observatory will be far greater on the
faster-spreading EPR.
March 23rd, 2006 at 5:40 am
I also support the 9N EPR site for the reasons given by the others. Also that area of the ocean will have a ship there on a frequent basis so that the mooring can be routinely serivced and better data can be obtained!
March 23rd, 2006 at 12:53 pm
In addition to the obvious argument that the faster spreading rate at the EPR might lead to more frequent volcano-tectonic and hydrothermal events there is another argument in favor of EPR versus Lucky Strike. Namely, we are already able to monitor events at slow-spreading, hotspot influenced ridges segments in Iceland and the Afar. These subaerial ridge segments differ far more from the EPR than from Lucky Strike. Perhaps most importantly, there are strong reasons to believe that magma is concentrated at or near the centers of slow-spreading segments. In contrast magma lenses are seen all along the axis of fast-spreading segments. Monitoring may help determine whether the very different magmatic structure affects how events occur.
March 24th, 2006 at 8:24 am
Andreas Thurnherr, LDEO:
The conceptual RFA proposals have been evaluated with the objective to “further refine science and engineering designs for the OOI facility […] and to specify the initial experimental and instrumentation needs of the user community for the OOI,” http://www.orionprogram.org/PDFs/RFA/RFA_OOI_CommExpts_Apr15.pdf
We should now advocate the establisment of a standard proposal process, in which projects requiring OOI infrastructure are evaluated by mail reviewers and unconflicted panels, following standard NSF criteria. When I got involved in the two R2K conceptual proposals it was my understanding that such a regular proposal process would be developed. In my opinion, ORION must be transparent and scientifically driven if it is to have a productive future. It is up to us (”the community”) to ensure that ORION is going to be an organization that is consistent with these ideals. The current attempt to get the R2K community to decide quickly whether the optimal site for a mid-ocean ridge
observatory is on the EPR or on the MAR serves neither of these ideals.
March 25th, 2006 at 1:33 pm
Marv Lilley, UW
I completely agree with Andreas. The “rush to Judgement” is a disservice to our science.
March 25th, 2006 at 6:49 pm
Maya Tolstoy, LDEO
I agree with Andreas and Marv. This should be a carefully considered community decision. At a minimum we need a community vote to pick a site with full disclosure of the available information (buoy budget constraints etc). The ideal would be an opportunity for the community to come together at a meeting to discuss this (perhaps the RTI). A decision this large, that will essentially seal the fate of the R2K successor program, needs to be made in a careful considered manner with full community input, and a transparent process.
March 27th, 2006 at 11:05 am
(Katie posting a comment from Chris)
Chris German, WHOI:
Hey All, in response to some of the comments - e.g. Ken McDonald, most
recently, about the increased likelihood of further eruptions etc. at 9N EPR.
Those interested might be inclined to check out the paper that Jian and I
opened the Geophysical Monograph of 2004 with, trying to link geophysical and hydrothermal systems - inspired by discussions from the InterRidge Theoretical Institute a number of you attended in 2002. In those calculations we used acoustic monitoring data for the EPR from 10N to 10S to look at what the likely “repeat rate” of a diking event might be at any given section of fast ridge and how long that might sustain hydrothermal venting. The motivation was comparing the 9N evolving case with juxtaposed data showing that the longest studied vents we know (21N EPR, TAG) can stay at steady state at 350C+ for decades. We ended up predicting that there might not be another eruption at 9N for another 40 years. This is provocative but Jian and I are both young enough to know we will still be alive and working long enough to be humiliated if proved wrong. But on that logic, rushing to a place that just HAD it’s moment of glory for the forseeable future might be the last place to plan to spend the next 15 years or so. According to our model, life could get pretty dull now for the next 20 years or more… Just a thought - feel free to take a look at the paper and discuss here why it is completely out to lunch
March 27th, 2006 at 12:28 pm
I have worked at both Lucky Strike (1993, 1996, 1997) and 9N EPR (since 1991, most recently in 2004 and will in 2006). You might note that I have not returned, or tried to return, to Lucky Strike in the last decade. Lucky Strike is ‘interesting’ in that the substrate there below the hydrothermal system is highly altered - its been active for a long time. Its not very interesting in the fact that it basically didn’t change (chemically or temperature wise wrt the hydrothermal fluids) over the 3 times we were there. Change helps one to decipher cause and effect - its very difficult to test your hypotheses in that regard in a static system. Yes, there was a seismic event at Lucky Stirke within the last decade, but does that mean there may be more, or that will be ‘it’ for quite a while. We just don’t know.
I view the 9N site as much more dynamic. Whenever we go back there we never know what we will find. The change is unlike any other place I have worked (and that is quite a few places). The first dive there is *always* exciting to see what is going on now, and the data work up is always exciting too. We certainly have our hypotheses, but lots of times that system has done the opposite of what I have thought it might do. It is an exciting place to work.
A comment Epp made with respect to the 9-10N EPR site was that ‘people voted with their feet’ to work there. Lots of work there during RIDGE by individual or small groups of PIs. Under R2K the work has started to be more organized and this is starting to yield results. I have not seen the same ‘voting with their feet’ (i.e., proposal pressure) in the US community to work at Lucky Strike. At AGU Tolstoy et al. showed *lots* of earthquakes were occurring at the 9N site, and we showed that the fluid chemistry and temperatures in most cases were not responding. Why? We don’t know. So lots of ‘events’ or ‘changes’ to test hypotheses as to why things change, or not. I still think its true that we know more about this ridge segment than just about any other on the planet, from the deep structure below it to the surficial expression on the seafloor. For future changes we have a good and diverse set of historical data we can build on.
There has been no discussion of logistics. Except for a few months in late summer-early fall (height of hurricane season), one can go to 9N, so the weather window is good. First time I went to Lucky Strike was early June, and we certainly got ‘beat-up’ by the weather. 9N is less than two days from several Mexican ports and 5 days or less from San Diego or the Panama Canal - so likely quite reachable by ship. Also Endeavour is in Canadian waters, Lucky Strike is in Portuguese waters which means access is controlled by those states. 9N is in international waters. As to data sharing, it is difficult enough within the US community - internationally it has proven to be even more problematic. RIDGE/R2K has not had a budget increase since 1990. I am concerned the US Community will not be able to get the $$$ in terms of individual or small groups of PIs to do the work that needs to be done to maximize the results from a buoy observatory placed at the Lucky Strike site.
March 27th, 2006 at 12:41 pm
PS One more logistical note in terms of our ship, etc. assets as observatories will need to be serviced. It has been helpful in the RIDGE and R2K communiteis that Endeavour and 9N have essentially opposite weather windows. Lucky Strike and Endeavour have largely the same weather window. Logistically we won’t be able to get the same ship or asset to both of them during the same season, as its well over a month’s steam between them.
March 28th, 2006 at 2:30 pm
Bob Dziak, NOAA/PMEL:
The benefits I see for support of the MAR (MoMAR) sites are that they closer to port, are scheduled for several international experiments beginning this year, and recently exhibited a magmatic event (2001). That said, of the two the EPR is the site most likely to be more dynamic (hydrothermally and magmatically) over time, and it is hard for those of us supporting the MAR to dispute this.
So where does that leave those of us that wish to have a research presence at the MAR and to continue to develop experiments that are international collaborations? I think Andreas and Marv make the best point, why should R2K and mid-ocean researchers be forced into a hasty choice now when really we should be pushing for transparent and scientifically productive future with all of us in ORION? Alternatively, as Javier posted, EU scientists are also planning an autonomous buoy at the MAR, so US researchers might have an opportunity to collaborate if the European bouy is deployed.
April 4th, 2006 at 10:09 am
Maya Tolstoy, LDEO
Following up on Chris German’s comments on eruption repeat rates at the EPR using the hydrophone data: every eruptive-like event that has been observed on the EPR hydrophone array has been in an anomalous area such as over-lapping spreading zone, near a triple junction, intra-transform spreading centers etc., where the crust might be anomalously cold/thick (and thus capable of producing larger earthquakes). OBS data (Sohn et al., 1995 and 2003-2004 EPR OBS data) shows that ‘normal’ sections of the ridge crest with very thin lithosphere appear to produce events of less than a magnitude 2 (the largest event to date in the OBS data at 9-50 is a magnitude 1.3mb). So it is most likely that eruptions along ‘normal’ segments of the EPR would go undetected by the full hydrophone array which has a magnitude detection threshold around 2-3mb. Therefore it’s probably not a good idea to use these data to infer anything about EPR eruption repeat rates.
April 5th, 2006 at 8:42 pm
Dave Butterfield, NOAA/PMEL:
I attended the first two days of the ORION Design and Implementation workshop last week, and since I missed out on the discussion in those last two days, I wrote some notes to post in the online discussion forum.
I think there was widespread agreement at the meeting, that the Regional Cabled Observatory, with roughly a 30-year lifetime, should be installed to maximize the areas reached, consistent with the plate-scale intent. One issue raised by the budget constraints is the southern route of the cable. To cut cost, the line proposed goes west from Newport, then south to the Blanco FZ, where an array of seismometers is proposed. Much better seismic coverage could be achieved if the cable reached the eastern end of the Blanco, but adding that loop increases the cost. This issue is still being considered.
During the ORION D&I workshop, the issue of having a major node at Cleft was raised. This is desirable in terms of linking earthquakes on the nearby FZ to changes in the hydrothermal system. It was not clear at the meeting if bringing up the issue of having a node at Cleft means that we are considering a tradeoff between Axial Volcano and Cleft. There are many reasons for installing a node of the RCO at Axial Volcano. Besides the interest in monitoring a robust volcano, there is a major water column profiling site near Axial, so there is a strong driver from physical oceanography to keep a node there. The robust magma supply, boiling, extensive hydrothermal systems, potential for geodetic monitoring, etc. also favor a node at Axial. It is clearly desirable to also have a node of some kind on the Cleft segment, and it would be a scientific shock if the US-installed portion of the RCO included only 1 ridge-crest hydrothermal site. Whether we can shift or allocate resources to put a node at Cleft AND Axial is something to explore. I donât think we should look at this as Cleft versus Axial at this point.
NOAA/PMEL has put resources into maintaining an acoustically linked observatory at Axial Volcano, and it can be expected that NOAA will continue to have an interest at Axial that will contribute resources to help the ORION effort.
Arguments in favor of a node at Axial Volcano:
1. Robust magma supply and very high likelihood of volcanic eruption in the 5-15 year timescale based on recent volcanic history and continued geodetic monitoring.
2. High likelihood that the volcanic eruption will be in the SE rift zone, where diking has been active in the last 10-1000 years, so monitoring can be focused in a high-probability area.
3. Three major venting areas around the caldera, including extensive diffuse vent areas spread over 10 km and multiple high-temperature vent sites.
4. Active magma degassing leading to extremely high gas content in hydrothermal fluids. Opportunity to monitor long-term magma degassing and how it relates to magmatic/volcanic activity.
5. Volcanic edifice allows geodetic monitoring of inflation and tilt.
6. Existing long time-series for fluid chemistry, plumes, and microbial ecology of vents.
7. Opportunity to learn what does and what does not affect hydrothermal output on the Axial volcanic edifice as opposed to surrounding ridge. This provides an important contrast to the MOR segments to the north and south.
Arguments in favor of a node at Cleft:
1. Proximity to Blanco FZ earthquake zone and likelihood of a hydrothermal effect (precursor and/or response) to significant earthquakes.
2. Extend hydrothermal monitoring to the southern end of the JFR.
3. An incomplete, but long time series of temperature and chemical measurements for background.
There is a lot more that could be said about these two sites, but I will leave it at that for now.
The initial concept for Neptune/RCO was a plate-scale observatory, and that should remain one of the primary driving forces behind the RCO.
All involved in the ORION effort should recognize that Neptune Canada stage 1 IS LINKED TO THE ORION PROJECT and scientists need to push proposals to install instruments on stage 1, not only as a testbed for stage 2, but as an early start to the ORION RCO, which is intended as a plate-scale observatory.
April 6th, 2006 at 6:57 am
Cindy Lee Van Dover, College of William & Mary:
Dear R2K Colleagues,
I was surprised by the proprietary nature of the Ocean Observatory
Proposals for MAR and EPR sites. In neither proposal did I see a
vision for developing the ocean observatories as part of the
oceanographic infrastructure for the community at large (US and
International). This vision was not explicitly requested in the RFA,
but I thought it was the spirit of the Ocean Observatory Concept. I
can understand that one wishes to define critical science questions
and identify pilot projects that would test the sea floor observatory
infrastructure before making it generally available to a larger
scientific public. Nevertheless, the most scientifically engaging
observatory will be one that can embrace a larger body of scientists
(both through the strength and importance of the scientific issues
that can be addressed and through a vision for access), that has a
life that builds on the specific interests of the proponents to
develop something much larger. There is some altruism in this
approach - the proponents of a successful observatory might well need
to back off from engagement in the science at the level of
investigator to a role as a steering committee and advocacy group for
individuals outside the core team. I had expected observatory
proposals to include infrastructure analogous to familiar models of
national facilities (ships, deep submergence assets, astronomical
observatories, national analytical laboratories, etc).
I read with interest the on-line discussion about time-series studies
and the focus on “events” defined as volcanic events. I urge the
community to consider the importance of studying events at other
scales. For biologists, observatories offer the promise of resolving
time-series phenomena that we have not yet begun to understand,
despite 30 years of interest in population dynamics of species
occupying vent communities. The timing of reproductive activities,
dispersal and retention of larvae, recruitment and colonization,
growth and survival - these are all parameters for which we have very
little robust published data at any hydrothermal vent. Whether or
not there is a volcanic eruption at Lucky Strike or 9N matters little
to obtaining some of these basic measures that are so far largely
elusive. (Yes, the volcanic events ALSO provide critical metrics,
but one need not build an observatory program that relies only on the
probability of a volcanic event happening; indeed, this would strike
me as a relatively weak proposal when viewed against one that took
advantage of time-series events occurring on tidal, lunar, and other
temporal scales.)
April 6th, 2006 at 11:29 am
I think we would be foolish to select Lucky strike if our goal is to study eruptions on ridge crests (my primary interest). Eruptions on the MAR are few and far between (decades to centuries to millennium) irrespective of whether we look at Iceland, the Azores or based on sea floor mapping. We could spend decades at MOMAR without ever seeing a magmatic event of any significance. I would be very surprised if the same were true at 9-50N. I have been impressed by the recent seismic data from 9-50N which shows much more seismicity than we saw at 9-50N ten years ago, suggesting it will erupt sometime soon. (We saw a pattern of intense seismicity at Axial for many years before its eruption).
We have much to learn about how fast spreading ridges erupt. I would be surprised if we saw the big diking events like we have seen at Axial or on Iceland. We know more about eruptions at slow spreading ridges (if central volcanos are an apt model) than we do on fast spreading ridges because of our experience with Axial, on Iceland and from studying worldwide volcanos. How do eruptions occur when there is no (evident) central volcano? That seems to be a situation unique to fast spreading ridges. The ORION deployment will have permanent sites at Axial (a big central volcano near/ over a hotspot somewhat like Lucky strike) and at Endeavour (a hydrothermal field in an axial valley).
Eruptions are not the only important thing going on at mid ocean ridges. It may be that the biology and hydrothermal fields at Lucky strike provide compelling reasons to monitor that site for decades. Is there evidence in the existing work at the site of significant changes in fauna or vent chemistry or temperatures over recent time (years to a decade)? I would ask the experts to weigh in on this issue. There seems to be evidence at other sites (TAG?) for hydrothermal fields to be stable on the MAR for long periods of time. I certainly agree that we should be putting more effort into studying slow spreading ridges, but maybe not through a long term monitoring program like the OOI.
Logistics: MOMAR is close to a port, but not one that is home to any boat of the UNOLS fleet so that from that perspective the two sites are similar. It has the disadvantage of being in a foreign EEZ. The US state department currently requires a long lead time to request clearances (6 months) which could be a problem for rapid response at MOMAR unless we rely solely on our European colleagues for that.
The weather is very good at 9-50N EPR with access year around. Hurricanes do not cross the site (they spawn north of 10N), while the MOMAR site is far enough north (37N) to have nasty weather much of the year. The MOMAR site experiences hurricanes about every five years (based on historical data). Hurricanes and winter storms will make it more difficult (expensive) to maintain a buoy at the site. Another disadvantage of the MOMAR site is the strong seabed tidal flows (23 cm/s or about 1/2 knot) will make it more difficult to maintain Alvin or a AUV on site.
April 11th, 2006 at 5:17 pm
Rachel Haymon, UCSB:
Many of you have made important points with which I agree about the value of placing a moored buoy observatory on the EPR at 8-11N. Without reiterating what others have said, I would like to mention three new points.
1) When we all signed on to support R2K as a community, we engaged in a laborious process of submitting competing proposals for selection of ISS sites. The EPR 8-11N site proposal was the top-scoring ISS proposal at the site selection panel, and for good scientific and logistical reasons which are all still true and compelling. Since 2000, even more reasons to like the EPR site have accrued, as Karen, Ken, Maya, Spahr and others pointed out. The whole idea of an ISS was that we would concentrate observations from mantle to microbes at carefully selected sites. So, it seems like a no-brainer to me, and a crucial a keeping of faith with the community, that we would allow the EPR 8-11N to develop as originally intended by placing a buoyed observatory here, and collecting time series data from it comparable to that available for the ISS at Juan de Fuca. This was, after all, the original R2K vision. At the R2K ISS Implementation and Planning Workshops, we specifically identified water column monitoring as a gap in the otherwise extraordinarily comprehensive programs at EPR 8-11N, and recommended repeatedly the installment of a buoyed observatory so that experiments like the one mentioned by Joe Resing could be conducted and merged with the other time series data from the EPR ISS. To back away from this now makes no scientific sense to me. Equally important, the undermining of community trust in collective endeavors has serious undesirable consequences.
2) The arguments about the dynamic behavior of the ridge crest at EPR 8-11N have been well-articulated by others above. I would like to mention that the young abyssal hills on the EPR are also very dynamic, due to the rapid (mmâs/year) uplift of these hills during the first half million years. Almost 50% of the hydrothermal heat loss from the ridge flank occurs from young abyssal hills within 4-5 million years, With very limited exploration, two weakly-active hydrothermal sites (one with dead Tevnia wormtubes) already have been stumbled upon in this environment on the EPR flank within the ISS area. This is not likely to be solely serendipitous, but suggests that there is a high spatial and temporal frequency of vents in young abyssal hill terrain, which one might expect for such a tectonically active setting where so much heat loss takes place. A moored buoyed observatory and seismic array would be very important to detecting near-ridge as well as ridge crest events, and could lead to new insights about interactions (especially biological ones) between ridge flank and ridge crest hydrothermal processes.
3) The Lucky Strike segment is influenced by the Azores hotspot, and is not a “typical” portion of the Mid-Atlantic Ridge. We are only just beginning to learn about ridge-hotspot interactions (especially where the hydrothermal systems are concerned), and there are important recent and pending results that have yet to be digested or published. Therefore it is unclear to me that we are fully ready as a community to commit to an observatory at Lucky Strike before we have thought through the best questions to ask, the best experiments to address these questions, and the best place to site the experiments. There was a good reason why the ridge-hotspot sites were not among the first sites chosen for an R2K ISS, as the EPR 8-11N was. We were right to set our priorities as we did, and I agree with Marv and Andreas that a hasty change in plan is ill-advised.
April 11th, 2006 at 9:56 pm
P.S. (4) I also want to mention that a large proportion of the ocean floor was created at fast-spreading centers, and hydrothermal plume studies seem to indicate that at the moment the fast-spreading part of the MOR is by far the most hydrothermally active. Therefore to understand global impacts of mid-ocean ridge processes, we must understand what is going on at fast spreading centers, and the EPR ISS clearly is a key part of this effort.
April 12th, 2006 at 3:20 pm
Felix Waldhauser, LDEO:
This message board lists sofar many compelling scientific (biological, chemical, AND geophysical) and logistical arguments made by numerous scientists, from various institutions, for why having a buoy at the EPR ISS site is worthwhile. On this same message board no such convincing arguments have been made for having the buoy at the MAR Lucky Strike site. Why is that?
From a geophysical point of view, one of the most important and exciting things to learn from a ridge observatory (whether located on a fast or slow spreading ridge) are the tectonic processes that control divergent plate boundaries, their effect on earthquake generation, and the evolution and structure of oceanic crust. The detailed study of these processes at the Lucky Strike site on the MAR are severely hampered by transient effects from the nearby hotspot, which in itself is not well understood. On the other hand, the EPR site is a more or less typical, reasonably simple fast spreading divergent plate boundary that offers a great environment to monitor and study in detail the mechanics of a piece of undisturbed spreading center.
One issue that I have not seen discussed on this message board is that the ORION program is pressured to present early results to convince congress to continue funding the program. One such exciting and preliminary result would be to get a real-time data stream from the ocean floor to schools, museums, peopleâs home, congress members (etc.), via the internet. Even if itâs only a camera pointed at a black smoker sending pictures in real-time, it would show that ORION has mastered the technical challenge. If FLIP can be used as a spar buoy, as discussed in SLC, such a real-time data stream can be established considerably faster than what the current time schedule proposes. FLIP can get faster to the EPR site than Lucky Strike, and the weather at the EPR site is more favorable for FLIP to operate than the conditions at the MAR site.
Real-time access to and from observatory instruments on the ocean floor is most justifiable at a site that exhibits strong dynamics. More than a decade of campaign style experiments at the EPR 9 50â site have shown that this segment is anything other than âdullâ. One just has to look at the continuously increasing seismicity rate that ranges from approximately 4 events/day in 1995 to 300 events/day in 2005, and counting. Significant short and long period changes (in both time and space) in biological communities and vent chemistry have been well documented during the course of many visits to the EPR site. Compared to the highly dynamic biological, chemical, and physical processes that characterize EPR 9 50â, Lucky Strike site is a rather static case and does not warrant a huge investment to facilitate a real-time monitoring system.
April 13th, 2006 at 10:29 am
J. Pablo Canales, WHOI:
I think that both sites have the potential to provide excellent science; each has its own strengths. The EPR 9-50N site is clearly very dynamic, but characterizing the MAR Lucky Strike (LS) site as âdullâ or static is a misrepresentation. The apparent lack of dynamism of LS could well be a consequence of having been observed and studied less extensively than 9-50N. Much it has been said about the larger likelihood of catching a seafloor eruption at the EPR 9-50N site, and the need to observe how the hydrothermal system and its associated ecosystems react and respond to it. But magma and eruptions are not the only factors to which the system responds. Tectonic events are likely to have also a big impact on fluid flow and the biological communities. LS is certainly a better site where to explore the role of tectonism on hydrothermal systems than 9-50N. As for its magmatic state, the LS hydrothermal system sits above a large magma chamber reflector (see Singh et al. Fall AGU 2005 abstract).
Having said that, it would also be misleading to advocate for LS as an observatory site where to learn how slow-spreading segments and hydrothermal systems work. If something characterizes slow-spreading ridges is their spatial and temporal variability. An observatory in LS will not be sufficient to fully understand such a system; more exploratory efforts in areas such as Lost City, TAG, and Rainbow will be needed for that.
April 18th, 2006 at 7:21 am
Posting a comment from Bill:
Bill Seyfried, University of Minnesota
I have long been peripherally involved in the EPR 9N ISS, but just now
retuning from the planning meeting at LDEO, I have become much more aware of the impressive level of integration that characterizes of all facets of the
program. In particular, the more than fifteen years of time series geochemical, geophysical, hydrothermal and biological data has elucidated important feedback mechanisms that are just now achieving a state of maturity sufficient to make testable predictions about of some of the most fundamental ridge-related processes. For example, that tidal influence has now been recognized in crustal seismic data as well as in the overlying chemistry, temperature and biologic activity of diffuse-flow hydrothermal systems is very significant. Time series observations involving the linkages between geophysical data and heat and mass fluxes manifest by high-temperature vent fluids is also contributing important new insights on the nature and temporal evolution of the magma/hydrothermal interface. Many other examples exist, but the common denominator of each is the maturity and highly interdisciplinary nature of the database developed at EPR 9-10N that is showing the way to the interconnectedness of the evolution of ridge systems. With the implementation of the infrastructure possible through the ORION program, the EPR 9N ISS is poised to reveal in short-order some truly remarkable discoveries with far reaching implications for ocean science on a global scale.
April 19th, 2006 at 9:12 am
George Luther, UD
I was pleased to see the April 26 e-mail from the RIDGE office indicating that the EPR site is recommended first for an observatory. This dynamic site has a long time series record and an observatory here would insure success for the ORION program for several reasons. First, the science here is compelling. Second, the integrated work over the years shows that many researchers will benefit from this science - integrated science is key to ORION’s success and EPR science has a long and proven track record. Third as total UNOLS ship days go from 4000 per year to 3000 per year in the very near future, it is clear that maximizing our ship time with observatory needs is vital to the success of all programs in Ocean Science.
April 19th, 2006 at 10:14 am
Posting for Adam:
Adam Schultz, Oregon State University
I would like to echo the earlier sentiment that there is a problem
with regard to this process - the selection of Ridge-friendly global
ORION sites does not follow the criteria established for selecting
R2K ISS sites; and the need to identify only one or two sites within
the ORION context is imposed from above, rather than driven by the
Ridge community. The fundamental difficulty is that the allocation
of funds for global buoy sites is inadequate relative to the
distribution of funds for the other elements of OOI, particularly
when set in the context of a large and vigorous Ridge community,
as well as a large global oceanographic and the solid Earth community.
As Larry Clark said in his talk at Salt Lake - the ocean observatory
initiative process started when a bunch of people started worrying
about installing a global network of borehole seismometers…
Having been involved in this process since 1987, I am disappointed
to see the way in which the global component has been given such a
small allocation. The allocation of resources appears to be skewed
- leaving the coverage of the entire planet, and all of the many
user communities, to argue over the smallest distribution of funds
within OOI.
This is the root of our problem. I am not convinced that we should
let this allocation go through without comment - rather we are being
forced into an uncomfortable trade-off.
This isn’t just bleating about getting burned. It is a real problem.
It is clear that there is superb science to be done at EPR 9-10N,
but also at MOMAR. This isn’t just about capturng different stages
of volcanic cycles or event detection. We don’t understand the
biogeochemistry of hydrothermal systems even in the near steady-state,
and the capabilities provided by continuous power and telemetry are
equally valid for 9-10N EPR as they are for MOMAR. From my perspective,
work at slow (and ultimately ultra-slow) spreading ridges presents
such a dramatically different range of problems than work at
intermediate-to-fast ridges, that these slower environments are of
greatest personal interest. Others will prefer fast spreading
environments - and that is fine - we should be able to study both.
Given the concentration of resources at Endeavour however, I think
MOMAR is a larger point of contrast than 9-10N EPR, so I have been
favoring that site (mildly), but would not consider it the end of
the world, on scientific grounds, if the final selection was at
9-10N instead.
To follow up on some previous comments - I don’t think it is the
case that we can expect that European Commission-funded science
will pick up the slack at MOMAR - the ESONET budget that is emerging
under the EC Framework 7 program calls for around 7M euro for ALL
observatory work within ESONET. It is not unreasonable to assume
that the portion going off to support science at MOMAR will be in
the region of only 1M euro (plus whatever individual national
programs such as CNRS in France might contribute). Consequently,
the US has a major role to play in establishing the observatory
there.
I do not view that fact that some (not all) of the MOMAR sites
(Lucky Strike and Menez Gwen) are in Portuguese waters presents any
real problem. I’ve done a lot of work in that area, and it is just
about the easiest to work in, is close to shore, etc.
If we are to have global span, and are to collaborate with scientists
around the world, as well as to develop standards for interoperability
for instruments and for data products, then MOMAR is an excellent
- possibly the best - place to do this.
Also, the draft document suggests that selection of the 9-10 EPR
site will serve the interests of ION for the ocean seismic network.
This is a point of confusion. During ODP Leg 203 we drilled a cased
reentry hole in the equatorial Pacific at about 2° - Site 1243A.
If the decision is taken to occupy 9-10N as a large buoy site, the
practicality is that the 1243A is too distant from 9-10N to be
connected to the buoy. This means that we would lose 1243A as a
viable networked observatory site, and instead would have to move
into an alternative borehole site in the Atlantic. So we’d miss an
opportunity to leverage substantial investment by ODP/IODP in 1243A.
If instead MOMAR is chosen for the main thrust of the buoy-based
ridge observatory site, then we would occupy 1243A in the equatorial
Pacific as a multidisciplinary seafloor observatory, including
borehole seismometer.
So two votes for MOMAR, but a vote for 9-10N EPR too!
April 19th, 2006 at 11:49 am
Posting for Dick:
Dick Von Herzen, WHOI
I was reading the comments on options for buoyed observatories and
the R2K position statement on them, the latter of which seems
reasonable. I agree with supporting both the EPR 9N site and MOMAR,
since they represent different spreading regimes and our understanding
of spreading ridges would be incomplete without both of them.
I also saw the discussion by Spahr (Webb, I guess) on favoring the
EPR site over MOMAR on the basis of weather. To argue to the contrary,
I believe it is possible for hurricanes (chubascos) to affect the EPR
site, particularly those storms that may cross the Panama bight from the
Caribbean sea and then strengthen again. Conversely, I believe that
most hurricanes that threaten MOMAR are much reduced in maximum strength
after traveling across most of the N. Atlantic. Probably the winter
weather is the most serious problem at MOMAR, although I guess that the
weather there may be reasonable for at least half the year (we had good
weather on a cruise there several years ago in early June). So let’s do
both (which should be possible in cooperation with at least USA and EU,
perhaps with respective emhases on EPR and MOMAR).
April 19th, 2006 at 12:00 pm
Posting for Adam:
Adam Soule, WHOI
I’ve read the draft of the recommendation to Orion and have some comments. For full disclosure purposes I should mention that although I’ve done the majority of my work at the EPR, I would prefer to see a buoy at Lucky Strike. I feel that the opportunities for growth and discovery at Lucky Strike are greater than at the EPR. Although my particular interests would likely not be enhanced by the initial depolyment of a bouy, it would be my hope that eventually, we would gain the capability to monitor volcanism and magma movement in the crust at the segment scale. Those processes are poorly understood at Lucky Strike and potentially much more interesting and than similar processes at the EPR site.
Some specific comments are below…
1. I was not at the steering committee meeting, but my impression from talking to the participants was not that there was a consensus to put forth 9N as our selected site. I hope it is clear that what is suggested in this draft does just that. I cannot imagine that we are going to get to select two of the global buoy sites. Suggesting a staged approach will be interpreted by Orion as R2K wanting the 9N site.
2. The suggestion that the seismicity data indicates an imminent eruption seems unconstrained. Although we may be rapidly approaching a seismic crisis (not 10 years from one) and that the ultimate event in that crisis was not clear. Whether it will be a volcanic eruption, a magmatic event that does not produce an eruption, or reflects hydrothermally driven changes in the AMC is not known.
That being said, I’m comfortable with the idea that an eruption is more likely at the EPR than at Lucky Strike, however, whether that eruption will be at 9Ë50′N is much less clear. While recurrence intervals of volcanic events at the EPR may be on the order of 10 years, that number is a segment scale estimate (over 100’s of km’s), and the recurrence interval at any one site is likely to be at 5-10 times greater. Capturing a magmatic event that perturbs the MOR system is a compelling goal for a buoy deployment, but one could argue that since Lucky Strike has a much more confined/focused crustal magma chamber, predicting the location of an eruption at that site is simpler.
3. Suggesting that deployment of a buoy at both sites is logistically similar is questionable. I don’t have a clear view of this, but my impression is that the proximity of Lucky Strike to the Azores makes it logistically favorable. This is especially true when considering the maintanence of the buoy, which may be accomplished in conjunction with the Europeans using their ship time.
I hope these comments are helpful in making this decision. In the end, I support a buoy at either site as I think it will make for exciting science, but feel that to date the Lucky Strike site may not have been given the proper consideration.
April 19th, 2006 at 2:50 pm
To the R2K steering committee:
Job well done on the memo. I think it makes a great deal of sense to focus on the EPR 9N ISS initially, based on the background work already done and future promise. R2K should remain an active participant in the European lead on MOMAR while forging ahead with a buoyed system at EPR9N as part of the ORION project. I share some of the concerns mentioned earlier regarding the ORION process. In particular, I agree that the global component is far too small. However, the train is now loaded and leaving the station, so we may as well get on board now or forget about it altogether.
Thank you for your efforts to bring this all together on such short notice.
April 19th, 2006 at 3:13 pm
I dont know who that guy “Kenneth” is, but I agree with him completely.
Ken Macdonald
April 19th, 2006 at 3:17 pm
I fully support the recommendations set forth in the Steering Committeeâs draft memo on priorities for deployment of a moored buoy observatory. It is wise as a first step for ORION to leverage and benefit from the investment that the community has at the EPR 8-11N ISS, and from the opportunity to monitor a fast-spreading ridge. This is win-win-win for ORION, R2K, and ridge science. It is also smart to plan for future collaboration with the Europeans at the MoMAR Site, as additional resources for this effort are made available. I agree completely that it would be better to allocate more OOI resources to the global component, I think we will get more bang for the buck if we do. Thanks to the Steering Committee and to all who have posted comments to this blog.
April 21st, 2006 at 10:56 am
I have been reluctant to post thoughts about âchoosing a global buoy ridge siteâ because they have been dominated with a degree of discontent over how the process (from RFA submissions of “concept proposals” have morphed into actual âproposed science proposalsâ, to the actual selection of two choices (rather than the selection of a generic global buoy/ridge site, that the Ridge community can openly enter into discussion on the important science enabled by different Ridge and buoy systems). So, I could start my comment with a discussion and critique of the process, but I will forego this. In reality, we stand now with the requirement to select either Lucky Strike/MoMar area or the 9°50âN ISS region for a global buoy observatory, and so my comments will be limited to those that are relevant to conducting temporal and spatial biological studies in these areas.
I have worked at Lucky Strike and 9°50âN areas over the past 10 years (with Alvin and Jason), conducting time-series ecological, evolutionary and population genetic studies. There are several qualities, that from a biological perspective, a ridge observatory (yes, I know that the proposed ridge buoys would and should not be limited to âridge crestâ studies) site would want to have (I very briefly present a fundamental few here) in order to provide a broad spectrum of scientific opportunities (without expressly presenting hypotheses here) and to enable more sophisticated experimentation/manipulation in future ridge biological studies:
1) diversity of species and habitats:
9°50âN is higher in species diversity, and also higher in the number (and biomass) of species with endosymbiotic microbes than Lucky Strike. This provides a larger scientific capability to examine a higher diversity of evolutionary (including co-evolution and novel adaptations) and ecological processes. Ecologically, most experiments would like controls/comparisons with things like disturbed and undisturbed communities of âsimilar composition or foundation speciesâ. Again, 9°50âN provides many more sites with which to achieve these experiements.
2) robust/extensive macrobial and microbial communities
The communities at Lucky Strike are dominated (in biomass) by mussels and shrimp, and are, with the exception of Sintra and Marker 4, of such a small size that extensive repeat/experimental/community sampling could have a dramatic impact on the ability of the fauna to recover. This area is also known to be marine protected area- does this have implications for the types of experiments and sampling that can be done? To me, the Lucky Strike faunal communities just aren’t extensive enough to provide a long-term experimental/manipulative approach that we are now moving forward on at 9°N because we have the background data/information to do finer and more sophisticated experiments with high interpretative power in this area. Fine-scale experiments at Lucky Strike are certainly possible and important (see my later comments). Only in comparison to 9°N, do I not see Lucky Strike habitats and communities being able to âsupportâ as large a comparative sampling program that is likely to occur as part of or in step with observatory science.
3) dynamic systems that present disturbance and habitat turnover on scales that are for amenable to experimentation 9°50âN provides a mosaic of disturbances (cracking and eruptive events) over a wide variety of timescales (some we have already documented), and utilized to understand integrated processes. This has been stated many times in the community input.
4) historic chemical, biological, geolocial, eruption, time-series data/knowledge
Many of the 9°50âN datasets, including time-series high-temperature and diffuse flow chemistry, patterns of faunal colonization, in-situ geochemistry, etc. represent the longest and most extensive of any ridge system. These sites don’t come close to one another when it comes to historical knowledge to guide our future research.
Now that I appear to be in favor or 9°N ISS as an observatory site, I would also like to state (as I did at the MAR workshop) that Lucky Strike (and Rainbow) offers benefits that make it high on the list for observatory sites, including the ability to conduct in-situ experiments with coordinatated laboratory manipulations (ecological, larval, and genetic) on animals and communities from such shallow depths given the ability to keep organisms alive much easier (similar to what has and can be done with seep fauna). I feel strongly that the MOMAR region has a tremendous amount to offer for the future of MOR biological research.
I agree well with Marvâs, Georgeâs, Cindyâs, Karenâs, Kenneth’s and Rachel M’s comments. I also agree with Javier in that the European Community is and will develop an observing system (to some extent) regardless of what the US Ridge commnity does. I suggest that the US science community will have the opportunity to invest efforts to utilize, build upon, and make use of any collaborative system employed at Lucky Strike, and so the ability to have access and do observatory science will be readily available and promoted to conduct fundamental and novel comparisons among the processes occurring on fast and slow-spreading ridges.
In the end, I favor 9°50âN being of the higher priority for establishing a global buoy observing system.
Thank you to the Steering Committee and the community for entering in this discussion.
April 22nd, 2006 at 9:20 am
Response from Susan Humphris
I am very disappointed at the draft recommendation by the R2K Steering Committee regarding OOI Mid-Ocean Ridge Observatories. In my opinion, the approach is unrealistic on two counts. First, there is no long-term OOI planning that suggests deployment of a second MOR observatory is under consideration for any time in the near future. I also believe that moving an existing observatory to another site is highly unlikely — the case can always be made that there is still highly compelling science to be done. Second, where are the funds going to come from to initiate the proposed preparatory activities at the Lucky Strike site? With no expectations of an increase in funding, what ISS work will R2K ramp down? Certainly not that at EPR if it is to become an observatory site; certainly not Endeavour as it is an integral part of the RCO; and certainly not Lau where studies have only recently begun. Hence, I see this commitment as having no possibility of fulfillment.
I agree with the Committee that the science at both the EPR and MAR sites is very compelling, and the choice is difficult. However, I think that the “possibility of a volcanic eruption” argument that has been voiced by many is a red herring. It has been made for both sites based on seismicity — and yet we simply to do have enough evidence to be able to predict the timing of such events with any reliability for either site. In addition, I would argue that if the goal of the exercise is to observe a volcanic eruption and its consequences (which in my estimation, it is not), then placing an observatory at one location is not the way to approach this problem.
I submit that the R2K community is losing its only likely chance to begin serious, integrated studies at slow spreading ridges that constitute >50% of the global MOR system. By 2012, when a ridge observatory is likely to be emplaced, we will have more than 20 years of time-series data (admittedly discontinuous) for the EPR at 9°N. Based on this, we will certainly be able to ask more sophisticated questions, but we will know little about temporal variability at slow spreading ridges. I would argue that the incremental advances in scientific understanding of crustal accretion processes will be much larger by placing an observatory at a slow spreading ridge site.
We are also missing a major opportunity for a true international collaboration, and the funding and leverage that comes with it. Our European colleagues are actively engaged in focused studies at the MoMAR site (~36-39°N). A spar buoy observatory at Lucky Strike is one component of this in which a major US role has been planned during the course of four workshops.
In summary, I believe that the approach recommended in this document is flawed and unrealistic. It will result in R2K, with its limited resources, becoming a program focused entirely on fast and intermediate spreading ridges. The larger vision and strategic planning for where the program should be going in the future, and the enormous opportunity being provided to us by ORION to begin some new studies, have unfortunately been missed entirely by the R2K Steering Committee.
Thank you for the opportunity to provide input to your draft recommendation.
April 23rd, 2006 at 7:10 pm
Rich Lutz, Rutgers University
As a biologist who has been working extensively on a variety of interdisciplinary studies at the 9N EPR site since 1991, I am writing to voice my very strong support for the steering committeeÂs decision that this site should serve as a location for a long-term oceanographic buoy. Given the invaluable geological, chemical, temperature, seismic and biological time-series data sets that exist at this location over the past 15 years, I feel strongly that there is no site along the mid-ocean ridge system more appropriate to maximize the utility and effectiveness of the interdisciplinary science that will result from deployment of a long-term buoy system.
April 24th, 2006 at 8:12 am
Maya Tolstoy, LDEO
In answer to Adam and Susan’s comments I’d like to raise an issue that to date has not been discussed here. Following email exchanges with John Collins (the ORION STAC representative on the global ridge buoy) in February it was made clear that the budget for the global buoy infrastructure will be quite limited, meaning that the scale of the observatory will be spatially limited (~5-10 km array), and first-order segment scale studies included in the MOMAR buoy proposal will not be possible. Since many of the slow-spreading ridge questions are on this segment scale, this limits the utility of a such a buoy to answer the slow-spreading questions that are most fundamentally different from the fast and intermediate systems. A buoy could be supplemented with non-real time instruments, but OOI infrastructure is being deployed to serve experiments that require real-time monitoring where you are able to respond to events of interest. The EPR site encompasses a volcanic segment which extends ~ 5-10 km and the questions posed and monitoring proposed for the EPR site can be addressed within the budget limitations. Because of the smaller scale of the monitoring region, the servicing costs are lower, and this means more money for science at a time when everyone is wondering where those $$ will come from.
Science-wise there is much more that makes the EPR site compelling than the possibility of an eruption. Whether there is an eruption or not in the immediate future there is no doubt that the site is changing dramatically from year to year in the seismicity, the fluid chemistry and the biology. In addition, as Tim articulated so well, the relative robustness of the biological communities at EPR is a key factor in terms of the kind of biological experiments that can be conducted. The unprecedented time series allows more sophisticated questions to be asked in almost all aspects of the work being done there, as well as providing the opportunity to monitor over an entire volcanic cycle.
April 24th, 2006 at 8:26 am
Posting a comment from Paul:
Paul Johnson, University of Washington
Below are my comments on the proposed comparative evaluation of the Lucky
Strike vs EPR9N sites in the RIDGE2K report.
I strongly disagree with the R2k report recommending EPR9N site as the
first, and likely only, buoyed ORION Mid Ocean Ridge site. The matter to
me seems to boil down to a single issue; Is the community going to simply
duplicate the Canadian effort on the Endeavour segment at the (very
similar) EPR site, or is it going to try to examine the full range of
mid-ocean ridge processes by also looking at the much different Lucky
Strike site?
The R2K report seemed to indicate that the ‘potential for eruption’ at the
EPR site was the entire rationale for picking that site. As someone who
has spent the last 25 years watching for an eruption on the Juan de Fuca,
I am very familiar with that particular exercise, and with self-delusion
that comes with thinking we can predict (or even successfully detect) an
imminent eruption with any degree of confidence. Since that effort is
now going to be continued on the JdeF with the Canadian RCO, duplication
at the EPR9N site makes no sense to me at all.
At some point we need to step back and consider how we should do a
mid-ocean ridge experiment. Given limited resources, should we pick two
similar sites and examine both closely, or should we instead try to look
at the relatively different end members of the entire range of the
phenomena, and try to learn these react to perturbations? Further, should
we pin all our hopes and resources on only one type of system
perturbation (volcanic activity), which is both rare and unpredictable,
or should we look at all types of disturbances, including large
earthquakes - which have a common occurrence, have a large area of
disturbance (100’s of miles) and provide much more information
on sub-surface fluid circulation processes than ‘localized’ volcanic
events.
In my view, a great deal of useful work has been done at the EPR, and
certainly should continue. On the other hand, if the mid-ocean ridge
goals of ORION are to examine the ‘real-time’ responses of crustal fluid
circulation to disturbances, then logic dictates including the Lucky
Strike site with the Endeavour Canadian RCO.
April 24th, 2006 at 4:32 pm
A couple clarifications from Javier Escartin, IPGP France:
While current speeds up to 23 cm/s have been measured at Lucky Strike, these are exceptional. The average current is ~10 cm/s. Of all current records, only 1% of the measurements are above 23 cm/s, and 12% above 15 cm/s. (these data are from on-bottom measurements during the DIVA’94 cruise)
At 130 m above the seafloor and over 400 days of measurements, the maximum speed measured was of 29 cm/s with an average of 9 cm/s (1.6% >20 cm/s and 9.6> 15 cm/s)
She also provided some information from 13°N at 100 m above the seafloor (she has data from the HERO 91-92 cruises) and velocities are indeed smaller : maximum velocity of 21 cm/s, average of 7 cm/s, and 0.3% >20 cm/s and 2.7%. >15 cm/s.
It is true that the EPR is ‘calmer’ than the LS area, but the differences are not as dramatic as people may have understood from the postings. Opreations have been regularly carried out in the area with submersible and ROV, and it has never been a problem.
I would like to clarify a point regarding Lucky Strike and investment. While it is true that funding is limited from the ORION side to cover large ridge areas, the limitation is true for both the EPR and Lucky Strike. In both cases an ORION-only will be limited to either a very small portion of the EPR (that shows considerable variations along its axis), or over the Lucky Strike hydrothermal vent area and its immediate vicinity. The advantage of Lucky Strike is the possibility of offseting some costs in collaboration with the EU effort (shiptime, etc) and complement infrastructure for a larger array than otherwise financed by ORION alone. Furthermore, many segment-scale processes that we are interested on do not require real-time monitoring, nor power supply, but autonomous instrumentation, particularly in areas with no hydrothermal activity. In the long term, and thinking on a 30-year perspective (as suggested at the ORION meeting), a MOMAR site may be able to spread over several segments and sites with different characteristics (e.g., Rainbow, Saldanha) that encompass hydrothermal systems that are fundamentally different and of high interest from the scientific point of view.
April 26th, 2006 at 6:57 am
Donna Blackman has in hand a letter from Mathilde (link to this letter available in April 4 email, link in main post above) spelling the wish of the EU ESONET program to cooperate with the US ORION program, primarily on common sites (i.e. MOMAR). ESONET is also financed at a 7M⏠level, but for ALL EU observatories. A call for proposals will be in place soon, and a MOMAR project will be submitted for funding at Lucky Strike… The maximum level of funding that we may expect is ~1 MâŹ. Mathilde’s letter should be useful as the basis for discussion or to provide elements regarding the EU side, if that is required
Apart from that, there has been 4 cruise proposals ranked as priority 1 at Lucky Strike for 2007 and 2008 in the French system - now the calendar is in the hands of IFREMER and oil courses.
April 26th, 2006 at 7:05 am
First of all, I would like to second the comments made by Andreas Thurnherr. In my opinion, it would have been in the best interest of science to actually ask for full proposals with accompanied peer review and an unbiased panel to make a proper and sound decision which site to select. However, it seems to me that we have past this point and now have to live with the current situation.
Certainly, very compelling arguments (scientifically and logistically) can be and have been made for either site. Many seem to argue in favor of EPR based on the high likelihood of future eruptive events. While witnessing such an event in real-time would indeed be very exciting (I for one would be thrilled to be able to sample the microbial community and its response after such an event), I agree with quite a few others, Susan, Cindy, and Adam Soule among them, that basing a decision on the likelihood of such an event is probably not warranted (as mentioned by Adam Soule, it is not clear that such an event, if it happens, would actually happen at 9.50N). As so well laid out by Cindy there are many other aspects of vent science that would benefit immensely from having an observatory. To say that Lucky Strike is âstaticâ and therefore does not warrant an observatory is therefore not appropriate. I agree with Adam Soule when he says that âthe Lucky Strike site may not have been given the proper consideration.â
There is another aspect that I would like to comment on: After having taken a look again at both RFAâs one thing that strikes me is that the RFA for EPR actually does lack a lot of the specifics and details that are provided in the RFA for MOMAR. This includes a detailed description of the instrumentation, methodology going to be used (Appendix II), and also an actual budget for a 6-year period with budget justification, including cost for instrumentation, analyses, and personnel. All of these are absent from the RFA for EPR. Thinking about the fact that these two RFAâs are now evaluated as science proposals, this is one aspect that in my opinion needs to be taken into consideration. I am surprised this issue has not been raised by anyone else, so maybe I am missing something here.
I would also like to mention that synergistic effects that would result from the collaboration with European scientists should not be underestimated. One important aspect is ship-time. Ship time is already tight and might become even more of an issue in the future. Thus, being able to use European ships could be very advantageous, not to mention the benefits of leveraging some of the other costs and the potential to expand the observatory at Lucky Strike to sites with different characteristics, e.g., Rainbow, Saldanha (as mentioned by Javier). For biologists, there is also the benefit of having a hydrothermal vent laboratory for conducting experiments under approximate in situ conditions close by at the University of Azores.
In summary, I am not necessarily arguing in favor of Lucky Strike. I can certainly see the benefits of having an observatory at EPR and would be highly interested in conducting science there, but I think the whole selection process has been flawed. Ideally, it would be great if we could install observatories at both sites in a staged way as suggested in the draft letter (the order might be debatable). However, I agree with Susan that this not very realistic and in the end it will be an either/or decision. I am really wondering why it would not be possible to strongly argue in favor of having a RIDGE observatory, but to postpone a decision for a site selection after a thorough review of proposals actually written for that purpose. Maybe that is too naĂŻve, but if this would be backed by the community as a whole I am sure a strong argument could be made.
April 26th, 2006 at 7:06 am
P.S. Stefan is Stefan Sievert.
April 26th, 2006 at 8:19 am
Emilie Hooft, University of Oregon
I want to highlight the science issues that I see as important in choosing a global OOI buoy site for ridge studies. I am not going to address the OOI process. The OOI infrastructure involves real-time monitoring. This means we are addressing processes that change over time (spanning the scale of minutes to decades). The following are my two primary scientific concerns about choosing a site:
1. I think that basing this decision on waiting for an eruptive event/events is NOT a sufficient justification for an OOI buoy. Eruptions only cover a small aspect of the science that involves processes that change with time; moreover it is hard to be sure of an eruption within any small area.
2. The time scales on which we will be able to monitor are primarily related to processes involving (i) stress changes due to tidal forcing, magmatic or tectonic events, (ii) the perturbation and evolution of hydrothermal flow and chemistry, and (iii) biological cycles and evolution.
The discussion has been very vocal for the EPR site and a lot of the reasoning has focused on the likelihood of an eruption at this site. Not enough consideration has been given to other processes that vary in time, in particular biological and hydrothermal processes. The Lucky Strike site has been portrayed as static and not varying over time. Recently there has been more discussion of hydrothermal and biological processes, but I think that it still lacks the necessary input from people studying slow-spreading ridges, including our European colleagues.
Here are some observations from the MoMAR area that are relevant to this discussion:
i. The inferred lack of temporal variability at slow-spreading vents is largely the result of infrequent sampling at slow spreading ridges (~5 year spacing). There is plenty of evidence for hydrothermal variability over a range of time-scales including dead chimneys [Humphris] and variations in the chemistry [Von Damm, 1998] and temperature of the vents [Langmuir]. Note that the TAG vents also show rapid changes in temperature with both chimneys and diffuse flow areas turning on and off at apparently random moments [Reves-Sohn et al., 2005 AGU]. The presence of two chemically distinct fluid sources [Von Damm; Charlou] in a single hydrothermal site is of particularly interest because the vent is underlain by a magma chamber.
ii. The biology also evolves over time. Microbial cover at Tour Eiffel has increased since 1998 [P.M. Sarradin]. In addition the LS ecosystem may have been affected by the magmatic event in 2001. Furthermore there are annual spawning cycles in the macrofauna that have only recently been detected because we normally visit the site in the summer. Such observations show that the ability to remotely monitor a site that has more difficult winter weather conditions will further advance our knowledge.
iii. The levels of seismicity at Lucky Strike are as high as at the EPR and Endeavour integrated Study sites and include both magmatic and tectonic events. Tens of microseismic events are detected per day [Dusunur et al, AGU 2005]; these events have magnitudes up to 3 and are located both above the mid-crustal magma sill and throughout the segment. A magmatic event in 2001 was detected using hydrophone recordings of seismicity [Dziak]. The stress changes causing and caused by the seismicity are a powerful tool for investigating the dynamics of hydrothermal systems.
iv. The area of venting is large, larger than the EPR site, and the heat flux is significant; estimates vary between 120-400 MW to 3800 MW from plume and He data [Wilson et al., 1996; Jean Baptiste et al., 1998].
v. Venting sites hosted by a range of rock types are within the MoMAR area including Rainbow, Menez Gwen and Saldanha. This area therefore has the potential to address fundamental questions relating to serpentinization, methane, and the deep biosphere. Expansion of studies at MoMAR during a 30-year program can thus address basic scientific processes.
April 26th, 2006 at 2:04 pm
This is NOT all about eruptions. The EPR 8-11N ISS is a dynamic site because of the spreading rate. An opening rate of over 1 m per decade means that cracking events are very frequent and intrusive/eruptive vents occur about once every ten years on average. The transform faults must slip often to accommodate plate motion, and the abyssal hills are uplifted rapidly too. It is a âred herringâ to divert attention from the actual consequences of rapid plate motion, which is that eventsâtectonic, volcanic, and hydrothermalâare more likely to occur more frequently. Furthermore we have evidence that they ARE occurring every few years at the EPR ISS, and likely will continue to do so.
Right now, multiple data sets at the EPR ISS (fluid chemistry, fluid temperatures, seismicity) support the prediction that this site continues to be a dynamic environment from which we can learn a great deal if allowed the infrastructure for in situ monitoring. Furthermore, we have a rich framework of prior observations and knowledge of fast-spreading processes that allows us to make predictions that can be tested through monitoring. ++The power of testing such predictions must not be underestimated or obscured.++ It is this rich context that made us designate the site as an ISS to begin with, and the data collected since 2000 has only enhanced this.
The idea that we should go to Lucky Strike because it is different from Endeavor and EPR makes no sense to me. Lots of places along the mid-ocean ridge are âdifferentâ in one way or another. I hope we can study all this diversity in the fullness of time. But it is hardly a strong argument for siting a (possibly one-of-a-kind) major infrastructure investment. At the end of the day, we have to be able to understand the data we collect, and be able to apply what we learn as broadly as possible. The EPR meets these criteria. I am unconvinced that Lucky Strike does.
It will take some years to put a buoyed observatory in place. Even if EPR 8-11N erupts tomorrow, we can count on it continuing to produce eventsâtectonic, magmatic, and hydrothermalâ on relatively short time scales, after the infrastructure is in place. Even with spotty monitoring, we know that over the past 20 years it has erupted at least 3 times (c. 1987 at 9 17âN; 1991 and 1992 at 9 50âN), and also has experienced non-eruptive cracking events (1985), and hydrothermal + seismicity increase (now). The fact is that it is not going to stop. Those plates just keep on moving⊠fast.
EPR 8-11N is a gift that keeps on giving, a natural experiment that keeps teaching us so much about ridges, based on what we have observed and what we are sure to be able to observe at this site. The bibliography of important work that has been done here speaks for itself. A broad spectrum of our community will benefit from putting the observatory here, and the OOI will have a guaranteed scientific success with a huge following. I urge the Steering Committee to stick with their plan.
April 27th, 2006 at 2:12 pm
To follow up on Emelie’s comments - and to restate beforehand that I think 9N is an exciting and dynamic site, and was well chosen as an R2K ISS, showing as it does dynamic changes in vent chemistry, frequency of eruptions etc - it should also be emphasized that the temporal variability of the MAR sites is not nearly as well sampled or established - but there are indicators of dynamic change, despite the paradigm that slow spreading should mean low magma budget, and less dynamism in general.
When we instrumented TAG in ‘94 immediately prior to ODP drilling (this was the British Russian Atlantic Vents Expedition - not the US pre-drilling work) - and then revisited it 6 months later to recover the instruments, there had been a dramatic change in the style of venting, and an eastward shift in the locus of venting activity. The area immediately south of the central smoker complex (what we called “Daibutsu Ridge”) has black smoke pouring out from just below the eastern edge of the ridge line, for a a distance of about 100 m. Six months later, this shut off - but the modest amount of venting just east of the eastern saddle on TAG (the “ODP” site) heated up considerably, and many small smokers were formed that had not been there previously. Our interpretation was this was not anthropogenic/drilling related, but part of the natural variability of TAG. So this is a “stable” system, but there may well be underlying periodicities that only sustained observations can reveal - requiring the infrastructure of an observatory. Less is known about Lucky Strike’s variability - although we are going back this summer and hope to gauge this better.
So even though it is unlikely we’ll see dramatic eruptive activity on the decadal scale at a MOMAR observatory, we’ll get to see an undisturbed system evolve under a completely different set of conditions than at Juan de Fuca or northern EPR. To me this has value. Indeed, only this way will we begin to get truly global sampling as part of the global observatory system.
One also should not discount the issue of survivability of observatory infrastructure, seismometers and other expensive instruments. Strange as this logic may seem - given that we only have a limited number of global installations to distribute, and each represents a single point of failure, the intense level of activity at 9N may present a hazard that has to be factored into the chances of successful long-term operations. From an engineering perspective, it might be risky to install the system in too dynamic (in volcanic terms) an area - and instead it might better be served (9N that is) by continuing active support for frequent expeditionary style operations. No one is arguing against continuing vigorous work at 9N - it is a fantastic site. Rather, which of all possible operating modes makes most sense there? Perhaps a large buoy installation isn’t the best approach for that particular site.