EPR 9 50 N venting & possible eruption
Information obtained by R/V Knorr cruise Apr 24-26, 2006, and during an ongoing R/V New Horizon cruise (on site May 10~17) indicates that a very recent seafloor eruption has occurred at the EPR 9N Integrated Studies Site (ISS).
See overview of the initial findings and information sent from New Horizon.
A second response cruise is now scheduled on Atlantis in late June. Eight Alvin dives are confirmed for this cruise and discussion of dive and night program activities is currently underway. All researchers are invited to take part in this discussion- input from investigators with previous main experience at other sites is welcome.
An explanation of the process for planning the Atlantis cruise in June was sent to the community May 3 email
Karen Von Damm is leading discussion of science priorities and cruise objectives. Please submit a comment here or email it to ridge2000@ucsd.edu and we can post it for you. Time is very short so please provide your input right away so that, as a group, we can design a plan that will optimize the dataset obtained in this very important early time period following the eruption.
If your comment has related detailed information that you would like to make available, R2K office can post that for you (send email to ridge2000@ucsd.edu with a PDF attachment). It will be linked here with title that indicates your name and comment number.
April 27th, 2006 at 10:36 pm
Tremedously exciting. Thank you to all involved for putting together a coordinated and efficient response effort. The intial observations are stunning. The recovered lava photo Alberto sent from the ship is also very encouraging. 210Po-210Pb dating will commence asap. We may be poised to learn a great deal if this event pans out the way intial signs are pointing, especially considering the liklihood that this was captured by the surviving OBSs. How far north of 9-51′N might this go? Along axis extent might surpass 1991-92 by a significant margin. I strongly support obtaining visual images of the seafloor as soon as possible, followed or accompanied by other TCS measurements as logistics allow. aloha, ken r.
May 3rd, 2006 at 12:27 pm
Yes, this is really a fantastic opportunity for R2K scientists, all of us who work on ridges, and in particular for those of us who have been investigating the 9-10 N area since the 1991-92 eruptions. I commend the group that was on the Knorr for all they have been doing to make sure they got the best initial data and working with us on shore to coordinate the data and samples so that the NH response cruise could be fully prepared as soon as possible and so that the dredged samples were handled in an appropriate manner. For those of you that don’t know this: Ken Rubin has NSF funding to date (using Po-Pb) new eruptions and has been doing this for a number of “events” on MOR. It is imperative that the dredged samples be sent to him ASAP so that he can start the process since the half-life is quite short. Ken and I have been communicating with Alberto Saal and Don Forsyth on board the Knorr to give them advice on how to handle, describe and deliver these initial samples. The R2K office has been in the loop regarding this and they have a proposed plan to handle requests for samples.
At this point there are many of us geochem types that are keen to work on these samples..HOWEVER….we must all keep in mind that we are not exactly sure there has been an eruption - i.e. one that has extruded new lava. In addition, the very nature of a dredge (~750m long) that was not transponder navigated leaves the “new” nature of these samples open to question. In addition, its possible that a number of flows could have been sampled and that what looks new is actually from the 1991 eruption that still looks very young (even in 2004, it was still very fresh looking).
I have been looking at our old Alvin dive notes from the area where the dredge was taken and the compositional range of lavas (only 6) is relatively limited so….. There is a very good chance the “new” samples could be significantly different. I also have good trace element data for many of these samples that is more precise and will allow us to better compare and contrast the new samples with what we already have. That being said, I think we petrogeek types need to wait a bit before running off and analyzing everything we normally do. Rubin’s results will be very important but more so will be what the response cruise that includes Fornari and his rabbit camera find/see. They too will be trying to recover new lava - provided they can find it. These samples have more of a chance to be THE new lava -if it exists. Because so much of the terrain along the AST in this area is very young looking, it may take some careful observations to definitively determine which is the new lava flow (unless it runs over more tubeworms!).
If nothing else this is a cautionary statement that we need good geologic/observational data and dates on lavas to go with them, to be certain about what constitutes being part of a new eruption. Once we have a consensus on this, we can attack the samples with vigor. However, I suggest for the immediate future, as Rubin is waiting for decay (sic), we can at least compare and contrast the gross geochemical and petrologic features of the dredge samples with previously recovered lavas from the dredge area. I have offered to do the microprobe analyses and petrographic description (with Rubin) on a selection of the first samples that are coming back from the Knorr and NH. I will share these with everyone. It will be particularly important to analyze the new samples along with some of the old ones since our analytical capabilities have gotten better and to avoid getting data from different methods and machines at different times. After the initial characterization and response cruise results we can decide if more needs to be done on these samples or if we should wait for in situ sampling by ROV or Alvin (assuming that happens).
Feel free to contact me directly if you have any comments or suggestions.
..heres hoping it’s still smoking…
mike perfit
May 5th, 2006 at 11:55 am
Doug Bartlett, Scripps Institution of Oceanography
Micro biological Studies
I am interested in culturing some of the EPR microbes and exploring the environmental genomics of the microbes at this site with others (see attached documents if you want more specifics). Even if someone was able to go to the heroic effort of obtaining sample for me, the culturing techniques that would ideally need to be performed soon after recovery would not be possible. Also, I doubt if it will be possible to filter 100-200 liters of seawater onto 3, 0.8 and 0.2 micron filters for me and my colleagues at the Venter Institute.
However, if it is possible for someone to obtain a few liters of seawater from as close to the site of eruption as is realistic that would be potentially very useful. It should be maintained cold, and to the extent it is possible a portion should be made anaerobic (e.g., by bubbling nitrogen gas through it). If there are any microbiologists/molecular biologists on the cruise they would likely be interested in the same kinds of samples. If they are funded to do any of this work I would not want to get in their way or duplicate their efforts. I have never done any high temp microbiology, my main interest is pressure effects on deep-sea microbes. If there are no microbiologists on this cruise that is a shame as many of my colleagues would realize that this is a golden opportunity to possibly culture and characterize novel microbes.
May 5th, 2006 at 12:11 pm
Monika Bright, U Vienna, Austria
meiofauna studies
The meiofauna community in general is known to response very quickly
to any environmental changes and often recruitment via the pelagial
occurs fast. We have been studying the meiofauna fauna community of
basically all different vent habitats at EPR 9N in collaboration
with several taxonomists covering all vent meiofauna taxa during the
past years . It would be very interesting to get samples from EPR at
this stage. In case a short Alvin cruise will be conducted I would
like to get samples of rocks, collected separated in a box and fixed
in 4% formalin.
May 5th, 2006 at 3:39 pm
Subdiscipline: Geology
It is thrilling to see the initial results obtained by Don et al. who were on Knorr, and of course we can plan the June response much better after the New Horizon cruise.
If the eruption is verified, and a second response cruise goes our in June, then it will be important to focus on observations that can only be made during or very shortly after an eruption; on baseline data collection and instrument deployment that sets the stage for future work; and on learning brand new things, by making observations that go beyond those made in 1991-92.
With regard to learning brand new things: in 1991-92, the eruption occurred between 9 51’N and 9 44.8’N, but perturbations of the hydrothermal system were observed from at least 10 02’N to 9 33’N. We also saw evidence that lava flowed downslope off-axis through tubes. Looking beyond the new eruption area, along-strike and off-axis, while things are still happening, has the potential to teach us new things about long-range effects of ridge crest diking/eruption. This is important to learn about, and will be unobservable after the event is finished.
Along these same lines, we do not know about interactions between ridge crest and ridge flank activity. So it would be desirable to explore the first abyssal hill scarps off-axis to see if the hydrothermal system here is activated by ridge crest event. Our prior work shows that there is hydrothermal fluid discharge on these hills, but we don’t know what triggers it.
The long-range observational work could be done with a towed camera/plume sensor system, or with one or two dives.
May 5th, 2006 at 3:53 pm
Subdiscipline: Coupled Microbiology and Chimney Mineral Studies
If the June cruise happens, Stefan Sievert and Rachel Haymon would like to sample chimneys for a collaborative study of chimney microbes and chimney minerals using the same samples. This will add to the long-term time series studies of chimneys at EPR 9N conducted by Haymon, and to Sievert’s already-funded microbial studies at EPR 9N scheduled for this year, and it will complement any fluid sampling that is done at the same vents where the chimneys are collected. We are interested in how the initial colonization of the chimneys influences the mineralization process, and vice versa. This is a great opportunity to observe this. In 1991, Haymon sampled the new “protochimneys” for mineral studies, but there were no complementary microbial studies. This time we could do both, and we will have the background knowledge from the 1991 observations that we can use to plan this work carefully. Observations made in June also could provide a baseline for a wonderful time series studies of mineral-microbe interaction. as the system evolves and the chimneys grow.
May 9th, 2006 at 12:50 pm
Stefan Sievert, WHOI
Subdiscipline: Microbiology
Craig Taylor, Roger Summons and myself have a funded NSF project entitled: Microbiology and Biogeochemistry of Autotrophic Microbes in the Subsurface at Hydrothermal Vents: Filamentous Sulfur Producing Bacteria (see summary on R2K website). The organisms we are interested in (Arcobacter) produce filamentous sulfur (filament dimensions ~1-3 x 50-500 um) from their oxidation of hydrogen sulfide to form mats within the interstices of warm water vents. These organisms are highly opportunistic and respond massively to eruptive events that result in significant elevations of hydrogen sulfide concentration in the vent fluids. The white flocculant material emanating out of so called “snow blower” vents during the last eruptive event at 9N was basically all filamentous sulfur produced by these organisms and supposedly accumulated on the vent floor to depths of 5 cm. This material was produced by the Arcobacter that is the focus of our study, and suggests massive stimulation of the growth of these organisms during that eruption. We are extremely interested in the present apparent eruption, especially if it results in another episode of the “snow blower” phenomenon where large amounts of filamentous sulfur are emitted. We are planning to sample hydrothermal fluids for subsequent microbiologal, molecular biological, and organic geochemical analyses. To this end, we have volunteered two of our funded dives towards a potential response cruise. As described so well in the comment by Rachel Haymon, we are also planning to obtain samples for coupled microbiology and chimney mineral studies. We are in contact with the group of Costa Vetriani to coordinate the microbiological studies. This event could represent a great opportunity to study microbial succession after an eruption, something that was lacking in response to 1991.
May 9th, 2006 at 4:26 pm
Kevin Hardy, Scripps Institution of Oceanography
Seafloor images
Two options for obtaining initial look at small areas of the seafloor could be made available for a response cruise. One option can also obtain a water sample. The intentionally simple systems include a towed or free-deployed camera. I have also rigged the camera to take water samples 2m off the bottom. The Niskin’s were triggered by a preprogrammed timed release inside the camera housing. I would use this approach with a free vehicle to recover water samples for Doug Bartlett from the Mariana Trench (I solved the deep sphere problem 4 years ago). We can add an external temperature probe. In the linked file (above) are photos of the configuration and adaptation as “CheapTow” (a tongue-in-cheek play on Fred Spiess’ “DeepTow”). The vehicle is something of a dope-on-a-rope as it uses chain to self-position it 2m off the bottom. No nav on the package, but you do get a view of a bottom and can make some estimate of where it is based on heading, line out, depth sounding, etc. There is a some chain that drags on the floor, but there are weak links in case it gets hung up in a crevice. Had a small development budget through NGS, but it works well enough to provide areas of interest for the manned vehicles.
May 14th, 2006 at 6:43 pm
Maya Tolstoy, Lamont-Doherty Earth Observatory
We’re very interested in trying to recover as many of the stuck OBSs as possible if there is a response cruise in June/July. Alvin will not be allowed to get close to the instruments, but a towed camera system with an acoustic transponder and hooks might be used to try and snag the instruments and pull them out of the lava (designed by Dan Fornari). This would be a night program and so would not cut into on site dive time. It should be fairly straight forward for the 3 instruments that still have active acoustics, but it will likely be harder to find the 5 that do not - especially if they have moved from their deployment location.
The value of the data is enormous since this is the first time we’ve had OBSs on top of an eruption, and we need to recover the instruments before their clock battery runs out (fall ‘06) for the data to be most useful. In addition the instruments are highly in demand for the coming year, and OBSIP is going to be stretched even thinner without them.
May 16th, 2006 at 11:52 am
If a response cruise is organized for July, I’d like to see at least these three activities to investigate larval supply and early metazoan colonization:
1) Recovery and redeployment of the sediment traps that were positioned in May 2006 near 9N50;
2) Deployment of colonization surfaces at active vents (new vents and also established ones if there are any left)
3) Collection of rock surfaces at newly active vents (as suggested by Monika Bright).
Ideally these activities would be coordinated with studies of microbial colonization and with chemical and video monitoring of vent sites.
May 22nd, 2006 at 12:48 pm
Peter Michael, The University of Tulsa
Subdisciplines = Geology + Petrology
We are studying how magma exsolves gas (CO2) as it erupts and flows along the seafloor. This requires recognition and detailed sampling and mapping of new flows. It is also necessary to identify eruptive vents or fissures, drainback deposits, and lava ponds. Considering how difficult it becomes to distinguish a new flow from all of the surrounding flows after only several months, it is critical that the new flow be mapped as thoroughly and as soon as possible. Detailed, thorough sampling of basalt is also important. It likely that the major and trace element chemistry of the entire flow is fairly uniform. But the volatile chemistry may be highly variable. We would like to extend our studies to any well-mapped flows: this usually means documented new flows. We would analyze volatiles in basalt glasses from near the eruptive fissure and far from the eruptive fissure. We would like to analyze glasses that chilled during drainback and during the earliest stages of the eruption. We might even be able to provide supporting evidence about the eruption in cases where the geological relations are not clear. Fortunately, the experienced crew that is planning to be at the ISS this summer will make the best observations possible. Our request is that they sample as many different basalt features as they can (even small samples are OK, if they have glass) from as wide an area as possible and record as much as possible about the samples’ geological relations: even their speculations or disagreements. We are most interested in knowing the relative times and distances that lava remained liquid, to compare with volatile contents. Also, please consider taking samples that look broken up or hyaloclastitic, in addition to the nice, solid, museum pieces.
May 25th, 2006 at 11:25 pm
*volcanology and geochronology*
It is possible to date the surface of the new lava flow to very high resolution (weeks to a month or two) with 210Po, as described in the document linked as #12 above. I have done this successfully on 6 prior submarine eruptions, including the 1991-2 eruptions and 9 50′N. Various version of this description have been circulating around for about 3 weeks but it is probably useful for the entire interested community to be aware of this capability. Maximum age resolution requires isotopic analyses right away on a time scale of the 210Po half-life (138 days). The TCS gang and some others are aware of this, which is why Knorr and New Horizon samples were sent to me the day those ships reached port. I have been working steadily on the Knorr dredged rock samples for the past month and have partial data for 2 of them. It is also possible to estimate the length of time magmas spent in the crust before eruption at decadal resolution using 210Pb and 226Ra (also described in the document). I have also begun this work.
Document #12 describes a large scale effort to map and date many samples (a dozen?) that I will not be able to conduct because there are not enough avaiable berths on the upcoming Atlantis cruise. Instead I plan to conduct a scaled back version of that work (4 or 5 samples?).