R/V Atlantis – DSV Alvin AT15‐36 Endeavour Segment and Axial Volcano Juan de Fuca Ridge, Northeast Pacific Ocean August 18 – September 7, 2008 Chief Scientist James F. Holden, University of Massachusetts Amherst, Geomicrobiology Project Project Leaders Daniela Di Iorio, University of Georgia, Heat and Fluid Fluxes David A. Butterfield, University of Washington and NOAA/PMEL, Axial Volcano Research David Clague, Monterey Bay Aquarium and Research Institute, Seafloor Mapping Cruise summary and acknowledgments: This cruise involved 23 scientists from three countries and studied two deep‐sea hydrothermal vent sites in the northeastern Pacific Ocean. It was a combination of two research programs funded by the National Science Foundation (NSF) to study the Endeavour Segment in Canadian territorial waters and one program funded by the National Oceanic and Atmospheric Administration (NOAA) to continue monitoring activity at Axial Volcano in U.S. waters. A middle‐school science teacher from Athens, GA and an undergraduate honors student from the University of Massachusetts Amherst participated in the cruise as part of our educational and public outreach program. We successfully completed 16 of our 18 planned Alvin dives with two dives lost due to poor weather. With Alvin, we collected 220 hydrothermal fluid samples, 14 sulfide chimney samples of various ages, and three basalt rock samples. Two McLane fluid samplers that were deployed for a year were recovered and replaced with two new samplers that will remain in place until next summer. The Alvin and McLane fluid and sulfide chimney samples will be used for microbiological and geochemical analyses and the development of a quantitative biogeochemical model of fluid alteration at Endeavour and Axial Volcano. We also collected black smoker temperature and fluid flow rate measurements in high spatial resolution on and up to 20 m above three of the massive sulfide structures in the Main Endeavour Field for flux modeling. Nine people, including five graduate students and the science teacher, made their first dive in Alvin. Other shipboard operations included seafloor mapping at Endeavour and Axial Volcano using an autonomous underwater vehicle (AUV) operated by the Monterey Bay Aquarium and Research Institute (MBARI). This was a no‐cost addition to the three funded programs onboard. Four AUV surveys over Endeavour collected 35 km2 of multibeam and sidescan bathymetry data with 1‐m lateral resolution from 4.3 km south of the Mothra vent field to 0.5 km north of the Sasquatch vent field. Two surveys at Axial Volcano collected 22 km2 of seafloor bathymetry over the southern portion of the caldera, completing a project that began in 2006 in collaboration with NOAA’s Pacific Marine Environmental Laboratory (PMEL). We conducted three vertical CTD casts over Axial Volcano, two tow‐yo CTD casts over the Main Endeavour field, and one background seawater vertical cast and collected 60 water column samples for chemical and microbiological analyses. We also collected SeaBeam seafloor bathymetry when weather conditions did not permit other operations, during AUV technical difficulties, and during transits between Endeavour and Axial Volcano. We are very grateful to the crews of the Atlantis and Alvin for their hard work and professionalism, and specifically to the captain of the Atlantis, A.D. Colburn, and the Alvin Expedition Leader, Patrick Hickey, for making this cruise a success. 1 2 AT15‐36 Alvin Atlantis Program to the Endeavour Segment and Axial Volcano on the Juan de Fuca Ridge, Northeast Pacific Ocean Table of contents: Page Cruise summary and acknowledgments 1 AT15‐36 personnel 4 1.0 Summary of cruise objectives and accomplishments 5 1.1 Geomicrobiology and fluid chemistry of diffuse hydrothermal fluids 5 1.2 Microbe‐mineral‐fluid interactions within hydrothermal sulfide deposits 6 1.3 High‐temperature fluid and heat fluxes from massive sulfide deposits 6 1.4 Axial Volcano hydrothermal vent monitoring 6 1.5 Methanogen phylogeny in diffuse fluids based on mcrA gene analysis 7 1.6 High‐resolution seafloor mapping using an autonomous underwater vehicle (AUV) 7 1.7 Age dating of extinct and active hydrothermal sulfide deposits 7 1.8 Microbially‐mediated nitrogen cycling in diffuse hydrothermal fluids 8 1.9 Viruses in hydrothermal vent systems 8 1.10 Education and public outreach 8 2.0 Dive summaries 10 2.1 Dive 4438: Main Endeavour Field – August 21, 2008 11 2.2 Dive 4439: Main Endeavour Field – August 22, 2008 15 2.3 Dive 4440: Main Endeavour Field – August 23, 2008 17 2.4 Dive 4441: Main Endeavour Field – August 24, 2008 19 2.5 Dive 4442: ASHES Vent Field, Axial Volcano – August 25, 2008 21 2.6 Dive 4443: Marker 33/Cloud Vent, Axial Volcano – August 26, 2008 22 2.7 Dive 4444: Coquille Vent Field and North, Axial Volcano – August 27, 2008 24 2.8 Dive 4445: International District, Axial Volcano – August 28, 2008 27 2.9 Dive 4446: Main Endeavour Field – August 29, 2008 30 2.10 Dive 4447: Main Endeavour Field – August 30, 2008 32 2.11 Dive 4448: Main Endeavour Field – August 31, 2008 34 2.12 Dive 4449: Main Endeavour Field – September 1, 2008 36 2.13 Dive 4450: Mothra Vent Field – September 2, 2008 39 2.14 Dive 4451: Sasquatch Vent Field and AUV Recovery – September 3, 2008 41 2.15 Dive 4452: Main Endeavour Field – September 4, 2008 43 2.16 Dive 4453: High Rise Vent Field – September 5, 2008 47 3.0 Summary of non‐dive operations 49 3.1 MBARI seafloor mapping AUV missions 49 3.2 SeaBeam bathymetry surveys 57 3.3 CTD water column analysis and sampling 58 3.4 Hydrothermal fluid sampling and shipboard analysis 58 4.0 Preliminary description of sulfide samples 60 Appendices 67 Table A1: Alvin dive statistics 67 Table A2: Summary of filtered HFS fluid samples 68 Table A3: Summary of unfiltered HFS fluid samples 70 Table A4: Summary of HFS sterivex filter samples 72 Table A5: Summary of HFS large‐volume bag samples 73 Table A6: Summary of major fluid samples 74 Table A7:Summary of gas‐tight fluid samples 75 Table A8: Summary of Alvin Niskin bottle samples 77 Table A9: Summary of sulfide and basalt rock samples 78 Table A10: Summary of CTD water column samples 79 3 AT15‐36 Personnel University of Massachusetts Amherst James F. Holden Chief Scientist Helene Ver Eecke Graduate Student Dmitriy Tokar Undergraduate Student University of Washington David A. Butterfield Scientist Eric Olsen Oceanographer Kevin Roe Oceanographer My Christensen Oceanographer Rika Andersen Graduate Student Oregon State University Lee Evans Oceanographer (Newport, OR) Pacific Marine Environmental Laboratory, NOAA Noah Lawrence‐Slavas Oceanographer (Seattle, WA) University of Georgia Daniela Di Iorio Scientist Guangyu Xu Graduate Student Rachael Parr Teacher Skidaway Institute of Oceanography Trent Moore Oceanographer Georgia State University Leonid Germanovich Scientist Marine Biological Laboratory Julie A. Huber Scientist University of Victoria Annie Bourbonnais Graduate Student University of Ottawa John Jamieson Graduate Student Monterey Bay Aquarium and Research Institute David Clague Scientist David Caress Scientist Hans Thomas Engineer Duane Thompson Engineer Marilena Calarco Graduate Student Captain Atlantis A.D. Colburn Alvin Crew Patrick Hickey Expedition Leader Sean Kelley Pilot Robert Waters Pilot David Walters Pilot‐in‐Training Anton Zafereo Pilot‐in‐Training Korey Verhein Pilot‐in‐Training Mike Skowronski Pilot‐in‐Training 4 Figure 1. R/V Atlantiscruisetrack for AT15‐36. 1.0 SUMMARY OF CRUISE OBJECTIVES AND ACCOMPLISHMENTS: 1.1 Geomicrobiology and Fluid Chemistry of Diffuse Hydrothermal Fluids (Holden (UMass), Butterfield (UW), Lilley (UW)) The goal of this study was to determine whether variations in environmental chemistry dictate which type of microorganisms will grow within a specific niche, and then quantitatively estimate the biogenic impact of these organisms on that environment. This will be done by determining the distribution and abundances of specific groups of organisms using culture‐based and molecular approaches. Particular attention was given to methanogens and hyperthermophilic autotrophic iron reducers and sulfur‐reducing heterotrophs. Low‐temperature, diffuse hydrothermal fluid samples were collected and co‐localized with high‐temperature fluids to estimate the degree of chemical alteration within the subsurface between the high‐temperature end‐member fluid and the diffuse fluid. These co‐localized fluids were collected at three sites at Axial Volcano (ASHES, Coquille, International District) and at ten sites along the Endeavour Segment (1 Mothra, 7 Main Endeavour Field, 2 High Rise). We also recovered two McLane fluid samplers from basalt‐hosted diffuse venting at Easter Island in the Main Endeavour Field and Marker 33 at Axial Volcano that will provide information on fluid chemistry variability over time. All of these fluid chemistry data will constrain the types of microbial processes that may occur. At the Endeavour Segment and Axial Volcano, a total of 210 hydrothermal fluid samples were collected: 142 Hydrothermal Fluid Sampler samples (60 filtered, 50 unfiltered, 26 sterivex filters, 6 large‐volume (4‐liter) bags), 26 titanium major fluid 5 samples, and 42 gas‐tight fluid samples. These were used for gas, major ion, and pH analyses; culturing of microorganisms; and molecular analyses. 1.2 Microbe‐Mineral‐Fluid Interactions within Hydrothermal Sulfide Deposits (Holden (UMass), Kelley (UW), Hannington (UOttawa)) The goal of this project was similar to the previous project in that it sought to determine how the combination of fluid chemistry and sulfide chimney mineralogy shape microbial community composition within hydrothermal sulfide chimneys. This will be done by examining the types, distributions, and abundances of various groups of microorganisms within sulfide samples using culture‐based, molecular, and microscopic methods with particular attention given to hyperthermophilic iron reducers, methanogens, and sulfur‐reducing heterotrophs. Three actively venting and morphologically varied sulfide chimneys were collected, and hydrothermal fluid samples were collected from the vent orifice that produced the sulfide following sampling. The wurtzite‐sphalerite rich region of these sulfides were removed and divided for quantitative hyperthermophile culturing; fluorescence in‐situ hybridization microscopy; 16S rRNA nucleotide sequencing; petrology; and electron microprobe and trace metal analysis; and Mössbauer, TES, FTIR and synchrotron spectroscopies. Sulfide samples recovered during the cruise have been sampled, archived, and documented through digital imagery and hand sample analyses. A subset of sulfide samples that were subsampled for co‐registered detailed microbiological studies and vent fluid analyses have been processed for major and trace element geochemical analyses. A subset of samples was also provided to Dr. Mark Hannington, University of Ottawa, for incorporation into their on‐going studies of sulfur isotopes and exploration of chimney dating. This work is the focus of a Ph.D. student at Ottawa. Sulfide samples have also been processes for petrographic analyses and delivery of sections is anticipated in 1‐2 months. During this next year, representative samples will be analyzed petrographically under transmitted and reflected light for characterization of petrogenesis, interpretation of vent chimney formation, and mineralogical characterization of the mincroenvironments where biofilm formation takes place. 1.3 High‐Temperature Fluid and Heat Fluxes from Massive Sulfide Deposits (Di Iorio (UGA), Germanovich (GaTech)) The objectives for this project were 1) recover the acoustic scintillation transmitter and receiver moorings that were deployed during cruise AT15‐34 and redeploy them around Hulk vent for two weeks, 2) quantify the hydrothermal plume characteristics using high frequency multibeam sonar (the SM2000) imagery in both horizontal and vertical planes, 3) quantify heat fluxes from individual black smoker vents on Dante, Hulk, Grotto, and TP vents, and 4) quantify the particle concentration from specific black smokers on the top of these sulfide structures and 20 m above Dante and Hulk within the integrated plume for assessing how much of the forward scattered acoustic propagation is affected by particles rather than temperature fluctuations. Five Alvin dives to the Main Endeavour Field were used to complete each of these objectives. 1.4 Axial Volcano Hydrothermal Vent Monitoring (Butterfield (UW/NOAA)) NOAA’s Pacific Marine Environmental Laboratory (PMEL) has been studying Axial Volcano under the New Millennium Observatory (NeMO) project since 1998, the year of a significant volcanic eruption in the southeast caldera and southern rift zone. The goals of this program (funded primarily by the NOAA/PMEL Vents program) are to follow the temporal evolution of the volcano and associated hydrothermal systems through an entire cycle from eruption to eruption, and to study in detail the links between microbial community structures and the chemical environment. In the ten years of the project, we have re‐sampled many vent sites for chemistry and microbiology nearly 6 every year. Dr. Julie Huber (MBL) and graduate student Andrew Opatkiewicz (UW) are both involved in detailed molecular studies of DNA collected from diffuse vet sites at Axial Volcano. Opatkiewicz is using the tRFLP technique to compare the most abundant phylotypes from a wide range of vent sites over time and comparing the microbial community structures with fluid chemistry using statistical techniques. For 2008, the primary goals of the project were to re‐sample selected vent sites from ASHES, Coquille/Vixen, Bag City, Marker 113, International District, Marker 33, and Cloud. We accomplished all of these sampling goals, but there was insufficient time to sample north of Marker 33, specifically Marker N3 and the Forum. As part of the time‐series study, we have monitored several different vents (high‐ and low‐ temperature) using McLane Remote Access Samplers (RAS) and temperature recorders. In 2007, we deployed a RAS with a PVC cover to focus warm fluid venting from the tubeworm‐filled crack at Marker 33. This sampler was recovered and replaced with a similar RS to be recovered in 2009. There were significant non‐tidal variations in temperature and composition recorded by the 2007‐2008 instrument that we recovered, but the causes of the variations is unclear. 1.5 Methanogen phylogeny in diffuse fluids based on mcrA gene analysis (Huber (MBL)) The objective of this project was to contribute to the Holden/Butterfield effort to model the biogenic flux of methane from diffuse flow vents at Axial Volcano and the Endeavour Segment. A molecular‐based approach was used to determine the abundance, diversity, and activity of methanogens in the subseafloor. We collected low‐temperature diffuse fluids for DNA‐ and RNA‐ based analyses of methanogens. The samples collected will be used to quantify methanogens using quantitative PCR of the mcrA gene, determine the diversity of methanogens using clone libraries and sequencing of the mcrA gene, and determine in‐situ expression of the mcrA gene in select samples using RNA extractions and reverse transcriptase quantitative (RT‐Q)‐PCR. This level of analysis, which includes all thermal classes of methanogens, will allow for detailed integration with cultivation and chemical measurements to build models of methane flux at deep‐sea hydrothermal vents. In addition to this effort, samples from Axial Volcano were collected for targeted culturing based on previous years’ results. Organisms of interest include epsilon‐proteobacteria, Archaeoglobus spp., Deferribacter spp., and Aciduloprofundum spp. This project was funded by L’Oreal and by the NASA Astrobiology Institute’s Directors Discretionary Fund. 1.6 High‐Resolution Seafloor Mapping using an Autonomous Underwater Vehicle (AUV) (Clague (MBARI)) The goal of this project was to collect four days of bathymetry data over the Axial Volcano caldera and rim to complete a high‐resolution bathymetry map started in 2006 and to commence mapping the Endeavour Segment and its flanks. Twelve missions were attempted, and six of these collected bathymetry data. Two days of mapping were performed at Axial Volcano, which completed mapping of the caldera floor and the southern half of the caldera rim, and four days at the Endeavour Segment. The Endeavour mapping ran throughout the axial valley from 4.3 km south of the Mothra vent field to 0.5 km north of the Sasquatch vent field. Despite lost time due to weather and numerous technical issues, we succeeded in collecting 27 hours of survey data at Axial Volcano and almost 55 hours of data along the Endeavour Segment. These translate into 140 km and 239 km of track at Axial Volcano and the Endeavour Segment, respectively. Combined we mapped about 57 km2 of seafloor at roughly 1‐m resolution. 1.7 Age Dating of Extinct and Active Hydrothermal Sulfide Deposits (Jamieson/Hannington (UOttawa)) A sampling program was performed to collect active and extinct sulfides of various ages from the Main and Mothra vent fields of the Endeavour Segment. By dating the sulfides, a time series for vent 7 field‐scale growth can be established. Hydrothermal barite within the sulfides will be dated with a novel geochronological technique using uranium series disequilibrium to determine the growth history and accumulation rates of the Endeavour hydrothermal field. Age dates are calculated by measuring the ratio of 226Ra‐to‐Ba in a barite sample. Over time, the 226Ra/Ba ratio decreases, due to radioactive decay of 226Ra (1,600 year half‐life). If the initial 226Ra/Ba ratio of a sample is known, then the decrease in activity of 226Ra in a sample will correspond to the age of the sample. Initial 226Ra/Ba ratios can be determined by measuring the ratios in barite from active chimneys. This technique is limited by the half‐life of 226Ra to samples ranging in age between 500 and 15,000 years. This time interval is ideal to evaluate the lifespan of vent fields, which are thought to exist over 1,000s to 10,000s of years. Fourteen sulfide samples were collected from Mothra, Main, and Sasquatch vent fields. These were cataloged, described and photographed (see section 4.0). Some of the samples will be archived at the University of Washington. The rest will be analyzed (mineralogy, whole‐rock geochemistry, and 226Ra activity) at the University of Ottawa. 1.8 Microbially‐Mediated Nitrogen Cycling in Diffuse Hydrothermal Fluids (Bourbonnais/Juniper (UVic), Butterfield (UW/NOAA) The goal of this project was to study microbially‐mediated nitrogen cycling in hydrothermal vents using a combination of isotopic and microbial molecular ecology methods. The nitrogen cycle in hydrothermal vents is poorly understood, especially the reactions involving bioavailable (i.e., fixed) nitrogen. The isotopic composition of dissolved inorganic nitrogen will be analyzed, which will inform us about potential nitrogen cycle transformations, and denitrification rates will be measure in diffuse hydrothermal fluids using 15N incubation techniques. The microbial communities mediating nitrogen cycle reactions will be determined using 16S rRNA sequencing functional gene analysis. Hydrothermal fluid samples were preserved from high and low temperature fluids for nutrient and nitrogen isotope analyses. DNA for the molecular analyses will come from the sterivex samples collected by Julie Huber at MBL. 1.9 Viruses in hydrothermal vent systems (Anderson/Baross (UW)) The objective of this project was to gather several large volume fluid samples for virus studies. This will provide preliminary data for a subsequent study of viruses in hydrothermal vent communities. Fluid samples (~ 4 liters) were collected from background seawater, two hydrothermal vent plumes and from diffuse hydrothermal output at six vent sites (Gollum, Marker 33, Marker 113, S&M, Hulk, and Godzilla). These samples were then concentrated and preserved for counting and imaging and stored for experimentation to determine whether a virus‐host system could be established. The goal is to better understand the role of viruses in the Axial Volcano and Endeavour Segment microbial ecosystem. Ultimately, our goal is to determine whether viruses act as mediators of horizontal gene transfer in vent ecosystems via transduction. 1.10 Education and Public Outreach (Parr/Di Iorio (UGA)) Ms. Rachael Parr, a middle school teacher from East Jackson Middle School in Athens, Georgia, was invited to participate in this expedition as part of Daniela Di Iorio’s educational outreach program. Our primary objectives for her participation and assistance in the science collection was to bring the research back to the middle school level and to develop a curriculum that will engage students in learning the science of hydrothermal vents. Classroom studies will include, but are not limited to: a. Hydrothermal heat flux: flow and temperature measurements b. Microbiology: microbial life found in and around the vents c. Diversity: the diversity of life found in and around the vents d. Geochemistry: the study of gases and volcanism 8 e. Plate tectonics: the types of plate boundaries and the movements within those boundaries f. Mapping: Comparing SeaBeam Mapping to AUV Mapping g. Technology: AUV, Alvin, acoustics, robotics, sonar, radar, and other technologies that are utilized on board h. Outreach: To develop programs that will reach other students. Since Georgia schools started on Aug 7, 2008, Ms. Parr had one week with her 7th grade students and took the opportunity to introduce the theory of plate tectonics to them. The Juan de Fuca Ridge was used as their primary example and she held discussions with the students as to why it is a heavily studied area by scientists. Other topics included 1) a discussion on buoyancy and Alvin with an inquiry activity where the students design and build a neutrally‐buoyant submersible, 2) background information on the R/V Atlantis and the various types of research conducted on her, 3) lessons on the methods and tools used by scientists to study hydrothermal vent systems, again with focus on the Juan de Fuca Ridge, 4) lessons where students compare geysers on land with deep‐sea hydrothermal vents, and 5) lessons on microbial life found around the vent systems and a comparison of these with those that live in your mouth. While at sea, Ms. Parr developed an online blog site (http://rparr.edublogs.org/) to communicate with students and teachers at East Jackson Middle School. The blog served the following purposes: a. The research activities taking place daily, along with pictures that helped in understanding the research, were posted. Much of the information was gathered through interviews with the scientists onboard Atlantis. b. Each day all science teachers in the school, regardless of the discipline taught, held a class discussion on the blog content for the day. Students were given the opportunity to respond to the blog and ask questions. Questions that the students had were answered the following day. c. The blog was also used to ask the students research questions, to which a log of answers was kept by the teacher for further discussion upon return to the classroom. Each day, approximately 410 students read the blog and there were on average 15 comments by students and classes participating in the project. It will be continued as a teaching and communication method with other schools. Ms. Parr also developed 6th‐grade Earth Science curriculum materials on the ship that began use upon her return to the classroom. These materials include, but are not limited to 1) understanding the structure of the Earth, 2) understanding the theory of plate tectonics, and 3) modeling and demonstrating the types of plate boundaries with specific emphasis on the Juan de Fuca Ridge. Inquiry investigations on buoyancy, velocity, density, pressure, mass and volume are in development. Ms. Parr’s 7th‐grade Life Science curriculum will cover microorganisms with a comparison of archaea and bacteria and the conditions in which these grow. Class activities and discussions will also include symbiotic relationships found at the hydrothermal vents. There will be a research project on marine sanctuaries and protected areas, and the students will watch videos that feature deep‐sea hydrothermal vents. Finally, Ms. Parr will share her experiences with the K‐12 teaching community through presentations on the benefits of connecting science teaching to the science community, her experience on her Alvin dive, and exploration beyond the classroom. She will also share a presentation with the science learning community or CLIMS (Community of Learners in Mathematics and Science) on connections to ‘real world’ science. 9
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