I. project overview
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- VI. BROADER IMPACTS: Linking Transformational Science, Education, Outreach, and Communication
- Results of Previous NSF Support
I. PROJECT OVERVIEWThe completion of Integrated Ocean Drilling Program (IODP) Exp 327 in Summer 2010 launched a series of multi-year, single-hole and cross-hole experiments in young oceanic crust (eastern flank of the Juan de Fuca Ridge (JFR)), to assess hydrogeologic, solute transport, and microbiological processes in multiple directions, depths and at numerous spatial and temporal scales (meters to kilometers, minutes to years) [1] The infrastructure to complete this work includes six boreholes (Holes 1026B, 1027C, 1301A, 1301B, 1362A, and 1362B) that are cased though the sediment section and open to the basaltic crust below. These boreholes are instrumented with sensors, loggers, and samplers located at depth in the crust and attached to wellheads at the seafloor. These systems are being used to monitor ambient subseafloor conditions in response to perturbations and quantify complex system responses within the crust [2, 2a]. Collectively, these experiments are elucidating fundamental questions related to linked properties and processes within the crust: (1) What is the nature (magnitude, distribution) of permeability in upper oceanic crust? (2) What are the magnitudes and directions of driving forces, fluid fluxes, and associated solute and heat transport? (3) What is the nature of fluid storage properties within the crust, including their pressure-, temporal- and spatial-dependence? (4) What are relationships between fluid flow, vertical and horizontal compartmentalization, distribution of microorganisms, alteration, structure, and primary crustal lithology? (5) How large are crustal fluid reservoirs, what are fluid and colloid flow velocities, and how do these respond to perturbations (pumping, tides, seismic events)? (6) What is spatial and temporal variability in phylogenetic and functional diversity of resident microbial communities, and what are the nature and magnitude of dominant metabolic processes? We are collecting samples and data using crustal borehole observatories ("CORKs") to address these questions, taking two primary approaches. First, we have placed sensors, samplers, and experiments at the seafloor, using wellhead instrumentation to monitor conditions and collect fluids from depth. Earlier studies have focused on installing and servicing these seafloor systems to recover samples and data, and to collecting discrete samples of crustal fluids and microbial materials using tubing that extends from the seafloor to depth. Second, we have placed autonomous and self-contained instruments deep below the seafloor, within the volcanic ocean crust, in five of the borehole observatories (Holes 1026B, 1301A/B, 1362A/B). These instruments include temperature loggers, fluid samplers, and microbial incubation habitats and enrichment studies, which will have been operating for 4 to 5 years in 2014, collecting samples and data that record the response to drilling operations, observatory installation, subsequent perturbation and response to tracer injection. As described later in this proposal, a small number of seafloor samples collected in Summer 2011 show that a multi-tracer transport experiment, initiated during IODP Expedition 327 (with injection of metal salts, inert gas tracer, and fluorescent particles, as part of a 24-hour pumping test), has resulted in direct evidence for tracer transport hundreds of meters between basement boreholes. The seafloor samples are limited in temporal and spatial resolution, in contrast to the downhole systems deployed prior to tracer introduction to the crust, which will provide greater spatial coverage and a continuous (multi-year) record. This proposal seeks support to recover samples from deep within instrumented boreholes, completing the first cross-hole hydrogeologic and tracer experiments attempted in the ocean crust. We request support for a 12-day on site ROV/submersible expedition to recover downhole instruments installed in subseafloor borehole observatories in 2009 and 2010. In addition, we propose to recover an autonomous flowmeter that is recording long-term discharge from one of the basement boreholes (as part of the cross-hole perturbation and sampling experiment), complete a final round of fluid and microbial sampling using seafloor valves and fittings to gather large-volume samples from depth, retrieve remaining wellhead samplers, and close valves to seal the CORKs so that they are available for future studies. After collection of samples and data, we will conduct an extensive analytical program to quantify concentrations and transport behavior of co-injected tracers (SF6, salts of Cs, Er, and Ho, two sizes of fluorescent microspheres and DAPI-stained cells, and chlorinity (for freshwater inputs); [1,2]), characterize microbial materials, and interpret the cross-hole and multi-depth pressure, thermal and chemical response to long-term discharge of fluids from two boreholes (1362A/B). This is a multi-investigator and multi-university proposal, with six co-PIs: Wheat (UAF), Fisher (UCSC), Cowen (UH), Clark (UCSB), Edwards (USC), and Becker (Miami). Four of the co-PIs (Wheat, Fisher, Cowen, and Edwards) also are co-PIs of the Center for Dark Energy Biosphere Investigations (C-DEBI), a Science Technology Center funded separately by NSF. These four co-PIs will draw upon existing C-DEBI support for partial support for students, postdocs, technicians, supplies, travel, and other expenses, significantly reducing budgets associated with the current proposal. In addition, although we are requesting UNOLS support for ship and ROV time as part of this proposal, we have submitted a complementary proposal to the Schmidt Ocean Institute (SOI), which would provide ship (R/V Falkor) and ROV (ROPOS) support should that proposal be approved. The SOI does NOT provide funds to conduct research, only ship and ROV time. This SOI proposal is currently in review (outcome anticipated in late August or early September), and if it is funded, we will not need NSF-funded ship or ROV support through UNOLS. The technical and scientific program we propose will be identical whether it is completed with SOI or UNOLS assets. The main difference would be the number of berths available, but we are planning for a lean shipboard party in any case, and a focused scientific plan comprising essential shipboard and land-based activities so that this suite of experiments can be completed. II. SCIENTIFIC MOTIVATION Most of the ocean floor is hydrogeologically active [e.g., 3, 4, 5] and the volcanic oceanic crust comprises a global-scale aquifer, containing as much fluid as that stored in ice caps and glaciers [6]. Hydrothermal fluid flows through the oceanic crust are equal to or greater than those from rivers to the ocean, effectively recycling the ocean every 105 to 106 yr [7-9]. Global hydrothermal flows influence: alteration of the lithosphere and the composition of flowing fluids and the ocean; subseafloor microbial ecosystems; and diagenetic, seismic, and magmatic activity along plate-boundary faults [e.g., 10-14]. Scientific ocean drilling has long sought to quantify the dynamics and impacts of fluid flow through the oceanic crust [15]. Although there have been notable successes in drilling seafloor spreading centers, particularly ore deposits and in sedimented environments, much work has focused on "ridge flanks" areas far from the magmatic influence of seafloor spreading, where overlying sediments stabilize the drillstring, and cooler basement conditions make sampling and experiments more tractable. Hydrogeologic testing of the ocean crust [16], has traditionally involved very short (20-30 min), single-hole experiments [17-19]. The recent development of pressure-tight, subseafloor observatories (CORKs) comprises a major advance in marine hydrogeologic studies [20, 21]. These systems allow thermal, pressure, chemical and microbial disturbances associated with drilling to dissipate, allowing monitoring, sampling and in situ experimentation. CORK systems have been used mainly for passive monitoring and sampling in single holes. Initial tracer tests with these systems have been limited to single holes and limited in scope [Gieskes et al., unpublished work in 504B, 22, 23]. Our project uses a three dimensional network of CORKed boreholes to run the first controlled, cross-hole tests, the first in-situ microbial enrichment experiments, and the most sophisticated microbial colonization experiments attempted in volcanic crust. These tests and experiments are possible only now, with the recent development of novel seafloor sampling systems (GeoMICROBE Sled; [24]), an autonomous flow meter [25], downhole osmotic systems [26], in-situ colonization and enrichment experimental systems [63], and high-resolution pressure recorders [2]. With such instrumentation and novel wellhead innovations, we are able to conduct the first hydrogeologic studies of the crust to assess vertical compartmentalization, and to quantify azimuthal (directional) fluid flow properties in oceanic crust. These experiments also are designed to provide the most pristine and most continuous multi-year record of ridge-flank crustal (borehole) fluids anywhere on the planet. The eastern flank of the JFR has become a de-facto "type setting" for ridge flank hydrothermal processes, in part because there is a long history of multidisciplinary research in this area. There are other locations where complementary studies are underway, most notably the North Pond field site, on young crust (8 Ma) west of the Mid-Atlantic Ridge, where conditions are cooler [28] but crustal fluid flow paths are less well defined. The eastern flank of the JFR has the most extensive network of observatories and instrumentation, arranged with a geometry that allows both single and cross-hole experimentation, including evaluation of lateral and vertical variations in scalar and vector (flow, transport) properties. There is nowhere else on the planet where these kinds of experiments can be completed at present, not without considerably greater investments in drilling time, infrastructure, and scientific instrumentation. Considerable work and resources have been focused on the JFR eastern flank in the last decade, and success has not come easily. But having made the long-term commitment and taken significant technical risks, we are poised to reap considerable scientific rewards with this final phase of operations. Proposed work will provide samples and data that are unique; are essential for understanding ocean crustal hydrogeology, biogeochemistry and microbiology; and cannot be obtained in any other way. Earlier short-term hydrologic tests in ocean crustal boreholes [18. 19, 29], and tests from open holes resulting from natural or induced differential pressures [30,31], have provided no information on formation compressibility, which is essential for understanding crustal response to transient pressure events. The use of natural formation overpressure to run long-term free flow experiments, as we are doing, quantifies formation transmissive and storage properties across a continuum of crustal scales (meters to tens of kilometers). The bulk formation properties indicated by earlier cross-hole responses in this area suggest permeability that is lower than determined with single hole tests [29], and several orders of magnitude less than estimated by numerical modeling and analyses of formation responses to tidal and tectonic perturbations. This discrepancy (which is contrary to expected scaling of permeability with the lateral scale of testing) may be reconciled if the upper crust in this area is azimuthally anisotropic with respect to basement permeability, with higher permeability in the "along-strike" direction (trending N20E). Testing this hypothesis is a fundamental goal of the complete experimental program, along with evaluating whether distinct physical and chemical zones in the crust are hydrogeologically connected or share common microbial ecosystems. Applying a suite of techniques using a single network of boreholes is the only way to accurately determine the nature of crustal permeability and storage properties, resolve scaling influences, and test the validity of idealized crustal representations commonly used in models [e.g., 32-37]. The JFR is an ideal place to address these issues, because individual tests can be run for years, delineating the scale-dependence of hydrologic properties using one experimental method. Similarly, there is no other way to assess actual fluid, solute, and particle flow directions and rates except through a tracer experiment. This kind of experiment has never before been attempted in the ocean crust. The extent of water mixing and water-rock interaction within an aquifer depends on effective porosity (fraction of open space involved in fluid flow) and hydrodynamic dispersivity (spreading of solutes by mechanical dispersion and diffusion) [38-43]. Understanding these properties is critical to successful reactive-transport modeling and interpreting the age distributions of subseafloor fluids. Simply observing tracer arrival across meters to kilometers is a significant accomplishment, but the most valuable records of tracer transport during these experiments remain deep below the seafloor. Samplers and loggers currently deployed at depth in existing CORKs contain long-term records of temperature, geochemical conditions, and microbial populations, from before, during, and after the initiation of cross-hole experiments. Recovery of this instrumentation will provide critical information contributing to the success of the multidisciplinary experiments. III. FIELD SITE AND EARLIER RESULTS Eastern Flank of the Juan de Fuca Ridge (JFR). Numerous studies summarize geology, geophysics, basement-fluid composition, hydrogeology, and microbiology within young seafloor on the eastern flank of the Endeavour segment of the JFR [e.g., 11, 23, 24-32]. Topographic relief associated with the JFR axis and abyssal hill bathymetry on the ridge flank has helped to trap turbidites flowing from the continental margin to the east (Fig. 1) [77]. This has resulted in burial of young oceanic basement rocks under thick (200 -700 m) sediments. Sediment cover is regionally thicker and more continuous to the east, but there are seamounts and smaller basement outcrops located up to 100 km east of the spreading center on 3.5-3.6 Ma crust. Regional basement relief is dominated by linear ridges and troughs oriented parallel to the spreading center and produced mainly by faulting, variations in ridge magmatism, and off-axis volcanism [78, 79]. Low-permeability sediment limits advective heat loss regionally, and leads to strong thermal and chemical differences between bottom seawater and basaltic formation fluids [e.g., 22]. ODP Exp. 168 (1996) and IODP Exp. 301 (2004). Ocean Drilling Program (ODP) Leg 168 drilled a transect of eight sites on 0.9 to 3.6 Ma crust east of the JFR [50]. These operations included installation of four CORKs that extended into uppermost basaltic crust, two of which are located on 3.5–3.6 Ma seafloor near the eastern end of the drilling transect (Holes 1026B and 1027C, Fig. 1) [51, 52]. Prior to ODP Leg 168, there was a largely two-dimensional view of the dominant fluid circulation pathways across the eastern flank of the JFR, with recharge occurring across large areas of basement exposure close to the ridge (near the western end of the Leg 168 transect), then flowing towards the east. However, results from ODP Leg 168 were inconsistent with this view and consistent with flow dominantly parallel to the spreading system to the west with seamounts to the south and north providing conduits for seawater inflow and egress [53, 54]. Numerical models of outcrop-to-outcrop hydrothermal circulation between recharging and discharging seamounts show that rapid flow is sustained (as a "hydrothermal siphon") and temperatures matched to observations if basement permeability along the flow path is about 10–11 m2 [55]. F  igure 1. Maps of the field sites. A. Regional map with primary field area (yellow box), located between the continental margin and JFR. B. Detail contour chart of individual CORK sites (circles) and nearby basaltic outcrops (yellow contours). Labeled depth contours are in meters. Most CORK sites are aligned along the direction of primary structural strike in basement, N20E, with Site 1027C located to the east (~70° oblique to strike).
Table 1. Primary work sites for proposed Summer 2014 Expedition. Locations are shown in Fig. 1.
IODP Exp. 301 returned to the eastern end of the Leg 168 transect and drilled deeper into basement; sampled sediment, basalt, and microbiological materials; replaced the borehole observatory in Hole 1026B; and established two additional CORK observatories at Site 1301 for use in long-term, multi-dimensional hydrogeologic experiments [4]. Results based on Expedition 301 and site surveys demonstrate that: (A) perturbations in crustal boreholes in this setting are transmitted across distances of at least 2.4 km, and natural circulation paths extend tens of kilometers, ideally suited for hydrologic tests with the geometery of the boreholes and observatories; (B) downhole temperature and osmotic sampling systems provide a quantitative measure of chemical and thermal changes in borehole conditions; (C) colonization substrates provide a useful means for characterizing microbial community composition; and (D) computer simulations coupled with a diversity of local and regional and data provide key constraints to hydrologic conditions. (A) Pressure data recovered in 2005 indicated that CORKs at Site 1301 were not sealed, because casing seals could not be installed during Exp. 301, and cold seawater was flowing down both holes and into basement. A large-scale assessment of basement hydrogeologic properties was made from the long-term pressure perturbation observed in the Hole 1027B CORK, resulting from leakage of cold bottom seawater into the crust at Site 1301 during the initial 13 months post-drilling [56]. Basement operations in Hole 1301B caused the greatest pressure response in Hole 1027C, 2.4 km away (Figs. 1 and 2) whereas operations in shallower Holes 1301A and 1026B had little or no influence, indicating that the shallowest crustal intervals are not the best connected laterally in this area. The dynamic cross-hole pressure response was modeled analytically, indicating a bulk permeability within the upper 300 m of crust of k = 0.7 to 2 x 10-12 m2, and aquifer compressibility of α = 3 to 9 x 10-10 Pa-1. This crustal permeability is at the lower end of estimates based on single-hole experiments [29], even through cross-hole tests investigate a much larger rock volume, extending ~10–30 km from the borehole. This difference can be reconciled by azimuthal anisotropy in basement permeability, with the direction between Sites 1301 and 1027 being 50° oblique to structural strike of basement (N20E) (Fig. 2B). The flow experiments currently underway, and to be completed as part of the current proposal, will assess permeability along strike and up to 65° oblique to strike, allowing the first direct test of permeability anisotropy in the ocean crust. 
Figure 2. Results from an inadvertent cross-hole experiment between Holes 1301B and 1027C. A. Pressure response in Hole 1027C CORK to long-term flow into Hole 1301B, 2.4 km away. Pressure record from Hole 1027C (blue line), corrected for tidal loading and other instantaneous response, is fit with an analytical model of crustal fluid flow, indicating basement permeability that is lower than indicated by packer tests or larger-scale methods. B. This pressure response could be explained by permeability anisotropy in basement, based on calculations shown. Calculated effective (apparent) permeability in an anisotropic medium depending on the angle of testing relative to the primary flow direction. Because the direction from Hole 1027C to 1301B is oriented 50° from strike, permeability is dominated by the "low permeability" direction. Tests to be completed as part of the current proposal will test and even more oblique direction, simultaneously with along-strike testing, resolving anisotropy. (B) During CORK servicing in Summer 2008, we learned that Hole 1301A had "turned around" and was discharging shimmering (~64°C) crustal fluids. Recovery of downhole OsmoSamplers and temperature loggers revealed that the abrupt change in borehole conditions occurred over just a few days in September 2007, following a long period of irregular downflow (Fig. 3). The composition of the fluid collected from Hole 1301A after Fall 2007 is similar in some ways to fluids from Baby Bare springs (to the south) and fluids that vented from Hole 1026B (to the north) [22]. The rapid change in fluid composition when borehole flow reversed illustrates both a lack of mixing of inflowing and (subsequently) outflowing fluids, and the extent of subseafloor inorganic and microbial reactions. The evolution of these fluids is analogous, in several respects, to the larger scale circulation pathway from Grizzly Bare to Baby Bare, between recharge and discharge sites [53,54, 57]. Furthermore, the record of Cs (introduced during sampling) documents exchange between the borehole and formation, illustrating the potential for hydrologic characterization using introduced tracers (albeit in a single hole). 
Figure 3. Four-year record of temperature and geochemistry of fluids from Hole 1301A illustrates hydrologic, geochemical, and microbial dynamics [22]. A. Mg (red and blue) and temperature (orange) data, relative to Mg data concentrations in seawater (black) and in formation fluids (green), from downhole sensors and OsmoSamplers (OS) in Hole 1301A. These data clearly illustrate the timing of the event and the path towards the event. B. Flow reversal is apparent from thermal record (purple), and is quantified by single-hole tracer experiment using Cs (blue data, idealized with dashed orange line). Rapid downflow slowed after ~1 year, then abruptly reversed during one week in 9/07. Rapid upflow of formation fluid shifted tracer baseline to match natural conditions (red triangles), as in Hole 1026B (dotted green line). (C) Subseafloor microbial substrate and enrichment experiments were recovered from the Hole 1301A CORK during servicing in Summer 2008, revealing a direct record of microbial adaptation to the changing hydrologic and biogeochemical conditions [27] (Fig. 4). Organisms that colonized the growth media initially were adapted to cold, oxidative conditions, but were subsequently replaced by microbes that are more representative of natural crustal conditions (warm, reducing), dominated by the Firmicutes phylum. Some sequences grouped near Ammonifex genera, thermophilic, chemolithoautotrophs capable of growth with hydrogen, formate, or pyruvate coupled to nitrate, sulfate, or S° reduction. The highest cell counts within flow-through experiments from Hole 1301A were found on samples of olivine, and culturable organisms from these samples were capable of nitrate reduction and iron oxidation [45]. In addition, repeat sampling from Hole 1301A has revealed significant differences in microbial community structure, with changes in both bacterial and archaeal lineages and absolute abundances (44). Figure 4. Microbiological growth substrate deployed and recovered after four years from depth in Holes 1026B and 1301A [40]. A. Polished chips of basalt (bas), peridotite (per), pyrite (pyr) and biotite (bio) as deployed in CORKs on Exp. 301. Top image is pristine substrate prior to deployment, center image is substrate recovered from Hole 1301A, bottom is substrate recovered from Hole 1026B. B. Cells observed on rock chip surfaces from Hole 1301A, as imaged by epifluorescent confocal microscopy, showing chains of bulbous cocci. 
(D) Analytical and numerical models simulated outcrop-to-outcrop hydrothermal circulation between Grizzly Bare and Baby Bare outcrops, separated by 52 km along-strike, to estimate the nature of basement properties required to allow inferred patterns and rates of fluid circulation [54, 57]. Outcrop-to-outcrop hydrothermal circulation can be sustained when basement permeability is ≥10-12 m2. At lower permeabilities, too much energy is lost during lateral fluid transport for circulation to continue without forcing, given the limited driving pressure difference at the base of recharging and discharging fluid columns. In addition, fluid temperatures in upper basement are highly sensitive to modeled permeability. When basement permeability is too high (10-10 to 10-9 m2), fluid circulation is so rapid that basement is chilled to temperatures below those seen regionally (modeled values of 20–50°C). A good match is achieved to observed upper basement temperatures of 60–65°C when lateral basement permeability is 10-11 m2, overlapping with values determined with single-hole packer experiments [29]. IODP Exp. 327 (2010). Two new subseafloor borehole observatory systems were installed in Holes U1362A and U1362B during IODP Exp. 327, a CORK instrument string previously deployed in Hole U1301B was recovered and replaced, and a long-term tracer experiment was initiated. Injected tracers included SF6, salts of Cs, Er, Ho, and several sizes of fluorescent microspheres and fluorescent-stained microbes filtered from surface seawater (particles). Tracers were injected as part of a 24-hour pumping experiment intended to test a large volume of basement rock around Hole 1362B, using Hole 1362B for perturbation and other CORKs for monitoring formation response. Instruments deployed at depth in nearby CORKs were designed and deployed specifically to sample tracers in the crust over time. During Atlantis/Jason Expedition AT18-07 in 2011, we: (1) recovered wellhead OsmoSampling systems deployed on pre-Exp. 327 CORKs, and deployed new OsmoSampling systems on the new CORKs (for geochemical sampling and microbial growth experiments); (2) downloaded long-term pressure data; (3) retrofited the old CORK in Hole 1027C for pressure monitoring with the newest generation of data loggers; (4) recovered and deployed a long-term GeoMICROBE sled used for autonomous, large-volume fluid sampling and electrochemistry [39]; (5) collected large volumes of fluids from depth using a variety of pumping, sampling and filtering systems; and (6) deployed an autonomous, electromagnetic flowmeter on one of the Site U1362 CORKs, then opened a large-diameter ball valve to initiate a long-term, cross-hole flow experiment [2 and 2a]. 
Figure 5. Examples of CORK wellheads and servicing operations during AT18-07 in Summer 2011. A. GeoMicrobe sled (right) and OsmoSamplers (left) connected to wellhead at Hole 1362B. B. Autonomous electro-magnetic flowmeter being deployed on wellhead of CORK in Hole 1362B. After installation of the flowmeter, a large-diameter ball valve was opened (yellow handle to upper right of image), resulting in a jet of shimmering, hydrothermal discharge from the hole. The flowmeter is measuring flow rate from the hole once/hour. Pressure data downloaded from the new CORKs at Site U1362 show that they are functioning as intended. Different equilibrium pressures are observed at multiple crustal depths in Hole 1362A, making this the first crustal CORK to successfully isolate multiple depth intervals, and the setting of a swellable packer element is apparent at the base of casing in Hole U1362B (where we have continuous monitoring of the cased interval). After the flowmeter was deployed on the Hole U1362B CORK (Fig. 5B), opening the ball valve released a shimmering jet of warm (~65°C) hydrothermal fluid from the crust below, causing a pressure perturbation that is spreading laterally and vertically through the oceanic crust (and being monitored by surrounding CORKs). The record of time-varying flow from Hole U1362B, and the pressure responses from this hole and other holes nearby will provide the first direct assessment of directional hydrologic properties in the upper oceanic crust. The flowmeter is recording fluid discharge hourly. Inlets to fluid sampling lines were placed in the top of the "chimney" above the flowmeter to collect geochemical and microbiological samples. The GeoMICROBE sled was also deployed on this hole to collect larger volume samples at 3-week intervals. One of the most exciting results from AT18-07 is the finding of tracers injected in Hole 1362B, during Exp. 327, in fluid samples recovered from depth in Hole 1301A, 500 m from the injection site (Fig. 6). These fluid samples were taken from the wellhead using the autonomous GeoMICROBE sled, which was deployed in 2010, prior to Exp. 327, and programmed to collect samples every three weeks. Microspheres injected in Hole 1362B arrived at Hole 1301A two months after injection. In addition, large Cs anomalies were found in discrete samples collected in 2011 from the wellheads of Holes 1362A and 1362B. The concentration in Hole 1362A, 300 m from the injection site, was 4x the seawater value, whereas fluids from Hole 1362B (injection site), have a Cs anomaly that is 40x the seawater value. These tracer data provide the first direct evidence for lateral hydrogeologic connection across distances of 300 to 500 m within the ocean crust, and the first quantitative measure of solute and particle velocities within the crust (on the order of several km/yr based on a simple consideration of distance and time of tracer arrival). However, available wellhead samples have a very limited temporal resolution, being restricted to times when the GeoMICROBE sled or researchers drew discrete samples. In contrast, the downhole Osmotic sampling systems we propose to recover, as part of the present proposal, comprise a continuous, four- to five-year record of borehole and crustal fluid composition, including time before, during, and after tracer injection. These instruments will provide the complete "breakthrough" curves of tracer concentration needed for proper interpretation of the tracer experiment, including a comparison of tracer transport rates and directions, and differences among gas, solute, and particle tracers. Figure 6. Initial results from the tracer experiment, with samples collected by the autonomous GeoMICROBE sled during four months following tracer injection in IODP Exp. 327. A simple consideration of the distance between sites and the travel time implied by the tracer arrival indicates particle flow rates in the crust on the order of several km/yr (Cowen, Guss et al. ,unpubl. Data). Collection of the downhole samplers will provide additional sites and a continuous data set. 
Late August 2012/early 2013. A scheduled expedition in mid-summer of 2012 has been postponed until early Summer 2013 because of ship mechanical problems. During this expedition we plan to recover the flowmeter system deployed on Hole 1362B in Summer 2011 and close the underlying ball valve, ending discharge from this hole and initiating pressure recovery in the upper crust. We plan to deploy a second flowmeter on the wellhead of Hole 1362A, 300 m away, which provides access to a deeper crustal interval, and open the ball valve on this wellhead. This would initiate a second, long-term discharge experiment, from a deeper interval of the ocean crust, facilitating additional fluid and microbial sampling and experiments as crustal fluid discharges at expected rates of 10 to 20 L/s. We also will recover seafloor experiments (GeoMICROBE sled and OsmoSamplers, and microbial experiments) that provide a snap-shot of conditions within the crust. All samples and instruments that will be recovered in 2013 (delayed from 2012 because of ship mechanical problems) will be processed, analyzed, integrated, and published using existing funding. But the most complete temporal record will be provided by the long-term downhole samplers, sensors, and experiments that will be extracted from the boreholes, as part of the work described in the next section of this proposal. IV. PLANNED WORK AND GOALS The present proposal requests support for (1) retrieving downhole samplers, sensors, and experiments, (2) recovering wellhead instruments deployed after Exp. 327 during earlier CORK servicing expeditions (fluid samplers, microbial growth substrate, flowmeter), (3) active collection of a final suite of wellhead samples using pumps, filters, and inline analyses, (4) analyzing data and samples collected as part of steps (1) to (3), and (5) integrating, interpreting, presenting and publishing results. These new samples and data will provide a much broader (spatial and temporal) spectrum of samples to constrain hydrologic, transport, and microbial processes and conditions available to date, representing a major advance in understanding ridge-flank hydrothermal systems. This necessary portion of the comprehensive experimental plan was not included in the last CORK servicing proposal because: (a) we could not make the strongest case in support of this work until we had the new observatories in place, seals and sampling intervals verified, and good evidence that the cross-hole experiments were working, and (b) the 4-5 year time frame between preparations for Exp. 327 and instrument and data recovery proposed herein would have made for an undesirably long proposal period (>5 years), which is not possible through standard NSF awards. Thus we broke the project up into parts; we are currently working with grants that support seafloor servicing and sampling, and request new support to cover costs associated with downhole instrumentation and a final round of surface sampling and downloads. There is no overlap in tasks associated with these two sets of proposals. We request support to complete the final phase of borehole monitoring and sampling to complete the full suite of single- and cross-hole experiments (Table 2). At the center of these studies is the cross-hole tracer test (begun with tracer injection on IODP Exp. 327 in 2010), and the multi-directional, cross-hole flow test (begun with measured borehole free-flow on AT18-07 in Summer 2011). Completing the tracer experiment requires recovery of downhole sampling and measurement systems so that we can quantify the presence of dissolved gas, ions, and particle tracers in the years following tracer injection. This is best done in Summer 2014, after these systems have been deployed for four years, recording a long period of geochemical response following drilling, CORK installation, and tracer injection. This will also provide a comprehensive view of borehole and nearby formation fluid conditions, as they return to a pre-drilling state. Experience has shown that often takes 2-3 years for borehole conditions to recover fully from the perturbation associated with drilling, casing, and other operations, and this should also allow for (virtually) complete dissipation of the tracer plume and return to background conditions. Table 2. Summary of tasks to be completed at each of the primary CORKs in Summer 2014.
NA = not applicable We propose to complete a final round of wellhead fluid and microbial sampling in 2014, download pressure data from all CORKs, recover the remaining OsmoSampler systems deployed on wellheads, recover the wellhead flowmeter, and close remaining valves so that the borehole observatories are left fully sealed, functional, and ready for future work. The CORKs installed in Holes 1362A and 1362B were sampled initially in Summer 2011, and are providing the most pristine materials recovered to date from multiple crustal depths. Extending the time series of active wellhead sampling from these holes, and from Hole 1301A, will provide important information on microbial dynamics. We propose to use a 24-48 hour deployment of the autonomous GeoMICROBE sampling sled at Hole 1362A, helping to resolve factors contributing to inter-annual variability indicated by longer-term sampling. To complete the proposed tasks we request ship support for an ROV dive program comprising 10 days of scientific operations, two days of transit (assumed to/from Seattle WA or Astoria, OR), one day for weather, one day for mechanical contingency, 14 at-sea days in total. This work is best accomplished during June to September, with July and August providing the most favorable sea state and weather window. We have completed similar operations in the past and are familiar with necessary tools and procedures required to complete the proposed work. For example, recovering instrument strings from the boreholes require either attaching a rope from Medea to the top plug and recovering the ROV and downhole package, or attaching flotation to the top plug and releasing the plug for surface recovery, or attaching a (plasma) rope to the top plug and pulling the downhole instruments out with a dedicated (shipboard) winch. We deployed the instrument string in Hole 1026B with Alvin in 2009, and this system currently provides real-time temperature data using the Neptune Canada cabled network. This system will have to be disconnected from the network prior to recovery (in collaboration with Neptune Canada colleagues, as has already been discussed). After instrument strings are recovered, holes will be sealed with a top plug (but without internal instrumentation) so that pressure monitoring can continue, pressure and temperature disturbance of the holes is minimized, and future biogeochemical and microbiological studies could be completed if desired in the future. The availability of CORK systems for future experiments and monitoring is an important legacy of IODP. V. POST EXPEDITION WORK PLANS Hydrogeologic Studies Earlier hydrogeologic experiments in this area have included single hole packer and thermal (flowmeter) tests and one inadvertent cross-hole experiment [e.g., 2, 29-31, 56]. A long-term test is currently underway, with discharge from Hole 1362B being monitored with an autonomous, electromagnetic flow meter [25], and pressure in the discharge hole and surrounding hole being monitored with wellhead pressure systems [2]. Interpretation of the initial cross-hole response is supported by an existing grant. We propose to extend this test by closing the valve and ending discharge from Hole 1362B, which will generate an additional cross-hole pressure response at other CORKs, and by placing a second flowmeter (already built as part of the earlier project) on Hole 1362A and opening the large valve on that wellhead. Hole 1362A is completed in basement at two depth intervals, with inflatable and swellable packers separating distinct crustal zones (with massive basalt flows separating regions of pillows and breccia) [2]. The deeper of the crustal intervals at Hole 1362A, extending ~430-530 mbsf (~190 to 290 m into basement), is connected to the large diameter ball valve on the wellhead through the inner 4-1/2 inch CORK casing. Pressure data downloaded from this CORK in Summer 2011 suggests that the natural basement overpressure in the deeper interval of Hole 1362A is greater than that measured in the single crustal interval isolated in Hole 1362B, and should result in more rapid discharge from the Hole 1362A wellhead when the valve is opened. This second long-term flow test will be superimposed on that from the earlier flow test, and the two signals are readily deconvolved by initial analysis of the first test. The second test will continue until Summer 2014, when the ball valve on the CORK in Hole 1362A will be closed, and the flowmeter will be recovered. This second test will apply, once again, to large region of the ocean crust, and will quantify (for the first time) the nature of vertical compartmentalization in the upper crust, based on responses from the shallower interval in the discharging hole (~310-410 mbsf, ~70-170 m into basement) and basement intervals being monitored at other CORKS located 200 to 2400 m away (Fig. 1B). Long-term discharge from depth in Hole 1362A will also allow sampling of fluids and microbial materials at the wellhead, as currently configured at Hole 1326B (Fig. 5). Results of the new hydrogeologic experiments will be analyzed with analytical and numerical models, with the latter including isothermal (conventional groundwater) and non-isothermal (fully-coupled simulations). This is the same approach to be taken with results from the first cross-hole discharge experiment, when the flowmeter data are recovered in 2013. Analyses will include an assessment of permeability, the thickness of permeable zones, extent of connections vertically and laterally in the crust, and nature of permeability anisotropy. There is likely to be some non-uniqueness to cross-hole interpretations, but this experiment will provide the best opportunity to date to resolve many aspects of ocean crustal hydrogeology on a ridge flank, given the temporal duration of tests (days to years), orientation of perturbation-to-observation directions (particularly with the second test run from a different discharge hole), and ability to monitor more than one depth interval in the crust. Additional analyses of pressure records from individual holes will include assessments of tidal and seismic event responses, as has been done with earlier records recovered from these and nearby boreholes [e.g., 4, 51]. Thermal Studies Recovery of downhole temperature loggers from CORKed boreholes will help to resolve a long-standing conundrum in subseafloor hydrogeologic analysis: the extent of isothermality in the upper ocean crust. Numerous earlier studies of seafloor heat flow patterns and crustal convection have been based on assumptions about the extent and significance of isothermality [e.g., 50; 58, 59], but this has not previously been measured directly on a ridge flank. In addition, there is disagreement among coupled models of seafloor hydrothermal circulation as to the primary fluid flow direction on ridge flanks. Recovery of autonomous temperature loggers deployed at multiple basement depths in Holes 1362A and 1362B during Exp. 327, along with pressure records from both holes, will help to resolve this question. Thermal data are also important for interpreting the rate of OsmoSampler collection. Additional strings of thermal loggers will be recovered from Hole 1301B, and the thermistor string will be recovered from Hole 1026B after disconnection from the Neptune Canada cable (as we have discussed with Neptune Canada colleagues). Tracer Experiment Several different OsmoSamplers (OS) were deployed in each of four boreholes. The standard OS and Acid Addition OS will be extracted, resulting in 1.2 ml aliquots (roughly 1200 per OS) [26]. Such a volume is sufficient for major (including chlorinity), minor, and trace element analysis (including Cs), a subset of these samples will be analyzed for contextual purposes. Four aliquots will be combined for REE analysis on a subset of these samples [62]. Together they form the foundation for additional analyses for microspheres (using the same aliquots) and SF6 (using Gas OS with copper tubing instead of Teflon tubing as the sample collection device) [26]. Samples for microsphere analyses will be filtered onto blackened membrane filters following procedures that prevent cross sample contamination; blank filters are prepared between every subsample. Entire filters are sealed under cover of over-sized cover slips and examined under an epi-fluorescent microscope. Dissolved SF6 analyses will be conducted by extracting the gas from 1-m-long sections of copper tubing (1.19 mm I.D.) This extraction system was constructed and tested with prior support and also serves for microspheres and solute collection. The extraction system collects the particle tracers with an in-line filter prior to extracting and analyzing the SF6 with a purge and trap methodology on a gas chromatograph equipped with an ECD. On the basis of injectate concentrations [2] and assuming 106:1 dilution, we will be able to detect SF6 tracer in 1 ml samples. We plan to analyze 1-m samples every 10 m for SF6. The 9-m sections between samples will be analyzed for microspheres, REEs, and when needed SF6 to produce robust breakthrough curves. Data sets showing tracer response with time will be analyzed to assess mean tracer transport rates, the extent of dispersion (spreading and mixing) during transport, and whether the ocean crust in this setting may function as a multi-porosity and/or multi-permeability medium. We will also assess differences in tracer-crustal interaction during transport, and the extent of tracer connection between multiple crustal depth intervals. Microbiology and Mineralogy of Incubation Experiments. Our principal tool for detecting and documenting microbial species diversity, distribution, and potential function will be through analysis of environmental DNA. The Edwards lab will investigate the phylogenetic and taxonomic diversity of bacteria and archaea using a combination of massively parallel ‘next generation’ sequencing of the 16S ribosomal RNA (rRNA) gene as well as select full-length Sanger-style sequencing and gene fingerprinting techniques. The next-generation sequencing will enable us to determine alpha- (richness, diversity, etc.) and beta-diversity (shared “species”, etc.) in and among the various samples, which will allow us to evaluate the emergence or disappearance of different microbial groups along sample gradients. Our team has extensive experience in extracting DNA from colonization substrates [63-64]. Appropriate positive and negative controls (including biological and technical replicates) will be analyzed to ensure quality control. We will conduct targeted metagenomic analysis with 454 GS FLX (454 Life Sciences) pyrosequencing facilities and technical support available at USC following an established sample processing pipeline. Select samples for this analysis will be identified based on taxonomic surveys to include the broadest diversity of communities. We will assemble the metagenomic reads to both simplify the data set and enhance our ability to analyze and annotate the sequence. There are now a variety of sequence assemblers available that are engineered to effectively assemble metagenomic data, including meta-velvet, IDBA, and Genovo. These tools allow not only assemble large consensus contigs, but also allow the analysis of variation from the consensus to shed light on diversity of genomic structure between subpopulations. We also will take advantage of publicly available metagenome analysis suites (and data repositories) like MG-RAST and CAMERA, and for larger contigs or scaffolds, or closed genomes, we will use the IGS annotation pipeline. Raw sequences will be submitted to the NCBI Sequence Read Archive, and products will be submitted to Genbank. Cell abundances in the samples will be evaluated by staining cells with SYBR Green II, propidium iodide, or other DNA-based stains followed by visualization and enumeration of cells by epifluorescence microscopy based on published protocols [e.g., 27, 45, 63]. The mineralogy of select samples may also be analyzed by scanning electron microscopy (SEM), mXAS and/or scanning transmission x-ray microscopy (STXM) according to standard protocols established in the Edwards lab [63, 65, 66]. We have regular access to mXAS and STXM for mineralogical and bioinorganic analyses at the Advanced Light Source at the UC, Berkeley (beamlines 5.3.2, 10.3.2, 11.0.2) [65, 66].
We propose to extend this model to the proposed 2014 expedition. Pending availability of space (which depends on the ship on which this work is completed), we will select and train ~4 science educator-communicators as members of the shipboard party. These personnel will apply to participate, similar to programs operated in 2011 and 2013, with an emphasis for those who can bring underrepresented expertise and diversity to the science party. Project co-PIs will explore opportunities to entrain individual local school teachers, curators, and others from their regions, particularly from nearby communities where there tends to be a lack of opportunity, as this will allow us to follow up over time with these EOC colleagues and their classrooms. We also plan to recruit among persons having expertise in the communication of technical and scientific information to a non-scientific audience: science journalists, illustrators/cartoonists, photojournalists, bloggers, and storytellers. These individual could be critical for helping to teach us to communicate the excitement of expedition-based research to classroom audiences and the public at large. We have succeeded in recruiting a diverse range of EOC personnel to participate on past oceanographic marine expeditions. To evaluate our success with the EOC component of this project, we will document contacts, measured by web hits, numbers of participants in live events, and numbers of inquiries (questions submitted, comments to blogs, requests for connections, number of downloads of podcasts, etc.). An external education consultant will measure longer-term impacts through two projects: (a) creating before and after photobook journals as a means of setting educator expectations and reflecting on experiences; and (2) conducting pre- and post-expedition surveys to quantify how participants' capacity and interest in expedition-related science changed through this set of experiences. Along with this overall EOC program, individual co-PIs will contribute to additional education and outreach activities through their respective institutions. For example, co-PI Wheat and two engineering colleagues developed the RETINA program (retina.engr.scu.edu) that involves hands-on, science-based (technologically oriented) educational modules for grades K-8. These modules focus on a scientific issue at a grade appropriate level and the technology required to address that issue. Past work has involved students in designing, fabricating, testing and deploying different sensors and robotic platforms, and the Call from the Deep Program [60, 61], that Wheat helped to run during a summer 2009 expedition and will be modified for use in 2014. Co-PI Cowen has integrated deep biosphere technology and science concepts into a yearly summer workshop for STEM teachers (Ali’i Workshop) and into a yearly Winter Astrobiology School for postdocs and advanced graduate students. Cowen is in discussion with colleagues at University of Hawaii's School of Education to link our scientific goals with educator training, and co-PI Fisher has linked with UCSC's CalTeach program, which trains STEM teachers. This research will also support numerous graduate and undergraduate student researchers, and publications and presentations for scientific, technical, and general audiences. In the past, when we have sailed 25-30 participants, including 3-4 postdocs, 6-8 graduate students, and several undergraduate researchers. This project provides excellent professional and technical training opportunities, involving cutting-edge tools and techniques. Collectively, this extensive EOC program will create professional partnerships between active scientists and creative educators, extending long beyond the scope or timeframe of this proposal. To emphasize the multi-dimensional and cross-disciplinary nature of these partnerships, we will include educators in presentations of science results at major national and international science meetings (e.g., AGU, GSA) and include scientists in presentations of education projects and results at major educational conferences (e.g., National Science Teachers’ Association). This “cross-pollination” between professions will help to assure that our EOC program has a broad impact among scientists, educators and the public. VII. DATA AND SAMPLE SHARING AND ARCHIVING (See IEDA-Data Management Plan in supplementary material) Data and sample sharing and archiving as part of this project will follow guidelines established by NSF and adopted with additional reporting activities by the Center for Dark Energy Biosphere Investigations (C-DEBI) NSF Science Technology Center (STC), as posted at the C-DEBI website (http://www.darkenergybiosphere.org/internal/docs/C-DEBIDataManagementPlan_2012draft.pdf). Space limitations preclude a comprehensive listing of these policies, but highlights include: • Rapid reporting on cruise activities and metadata associated with sampling and measurements, posted at the C-DEBI network website (www.darkenergybiosphere.org). • Broad data distribution after collection following a standard moratorium of two years, to provide researchers an opportunity to complete analyses and submit initial publications. • Protection for students by extension of the "standard" moratorium through degree completion and/or publication submission. • Standard release of complete data sets as digital supplements accompanying papers. • Archiving in widely accessible community databases, such as the Marine Geoscience Data System (www.marine-geo.org), EarthChem (www.earthchem.org), VentDB (www.ventdb.org), the National Center for Biotechnology Information (www.ncbi.nlm.nih.gov), and the Integrated Microbial Genomes (IMG) database (http://img.jgi.doe.gov/cgi-bin/pub/main.cgi). VIII CO-PI-RESPONSIBILITIES, RELATED PROGRAMS, REULSTS OF PRIOR SUPPORT Co-PI Responsibilities. Wheat is the lead co-PI, responsible for overall project planning and project management, including the recovery of all downhole and seafloor samplers and sensors. Fluids from OsmoSampler systems, the GeoMICROBE sled, and discrete samples collected during ROV dives will be analyze for dissolved ions in general and with a particular emphasis on tracers: chlorinity (for freshwater)Cs, Er, and Ho. Wheat also will provide the samples (OsmoSamplers) for Clark to conduct analyses on dissolved gases, for Cowen to detect microsphers, and for Edwards to conduct microbial experiments in a structured setting [e.g., 40]. Fisher will focus on completion, processing and interpretation of cross-hole experiments including data from the autonomous flow meter. Fisher will collaborate with Clark, Cowen, and Wheat on interpretation of tracer experiments, and Becker and E. Davis (PGC) on interpretation of pressure data. Becker will take primary responsibility for at-sea operations for downloading CORK pressure data, using existing underwater-mateable connectors and computer capabilities, and sealing the boreholes for potential future experiments using existing top plugs and pulling/running tools. He will also focus on interpretation of the pressure data, continuing a long-term collaboration with Fisher and E. Davis (PGC). Cowen will be responsible for the colloid (stained microorganisms and fluorescent microsphere) component of the tracer transport experiment. Cowen will manage the deployment/recovery of instrumented/sampling sled (GeoMICROBE), other wellhead large volume fluid collection and analyze subsamples from sled and OsmoSamplers for colloid tracers. Clark will be responsible for single- and cross-hole analysis of tracer results, focusing on SF6, using the gas chromatograph system he developed. Clark will oversee collection and analysis of gas-tight tracer samples from wellheads, and work with Fisher, Cowen, and Wheat on quantitative analysis of results. Edwards will oversee recovery, analysis and interpretation of microbiological incubation experiments. This includes phylogenetic (16rRNA) and metagenomic analysis in addition to synchrotron based mineralogical analysis of incubated materials. Institutional budget justifications describe co-PI responsibilities in detail.
As noted earlier, four of the co-PIs on the current proposal (Cowen, Edwards, Fisher, and Wheat) are also co-PIs on a NSF-STC proposal (K. Edwards, lead co-PI), for the Center for Dark Energy Biosphere Investigations (C-DEBI), funding for which began as of 10/9/10. The broader STC shares some goals with the proposed recovery of samplers and experiments, but there is no overlap in funding between this proposal and the STC. Co-PI budgets for Cowen, Fisher, Edwards and Wheat are limited because a portion of their participation costs are covered by STC budgets, as discussed in detail in institutional budget justifications and summarized in Table 3. Table 3. Summary of person months for the two year duration of the proposed work that is requested of NSF (and those supported by separate C-DEBI funding) to help complete the proposed work
This project results from more than a decade of multidisciplinary technical development. New tools and techniques that are available to the scientific community as a result (at least in part, if not in entirety) of JFR CORK work include: redesigned casing seals and the casing cementing program; redesigned CORK wellheads to permit free flow without removing the top plug ("L-CORK"); redesigned the top plug and associated seal/latch mechanism; designed an electronic release system for instrument string deployment; designed and implemented an instrument string recovery system capable of operating from a conventional oceanographic vessel once a cable is connected to the top plug; performed geochemical evaluation of coating materials that can be used on CORK components to minimize microbiological and inorganic contamination; designed a system for assuring that CORK casing packers will maintain inflation over a period of years; evaluated a packer system to be used for a 24-hour pumping/tracer injection experiment; designed a novel fluid sampler for the 24-hour pump test; designed an autonomous flow meter system for use during free-flow from the well head; developed a shipboard tracer injection system; designed instrumented submersible-mobile and autonomous instrumented ‘clean pumping’ systems (including temperature, fluid flow, Eh and pH sensors, and in-situ electrochemical and filtration technology), and new downhole experiments and sampler capabilities [ 2, 24-27]. Each of these new developments is critical to achieving the proposed science. Some experimental systems recovered during proposed work will be available for community use on other projects, and additional systems will be designed and built as a result, facilitating additional research and discovery. Results of Previous NSF SupportBecker: OCE04-00471, $729,418, 02/04–09/10, Collaborative Research: The Hydrogeological Architecture of Basaltic Ocean Crust: CORK Experiments for the Initial IODP Expedition on the Flank of the Juan de Fuca Ridge. This was the lead grant in a group of three grants that supported the CORK instrumentation installed on Exp. 301 and subsequent submersible operations described above. In particular, this grant supported acquisition of the pressure-logging systems and downhole temperature loggers, data from which is shown in Figs. 2 and 3. Nine peer-reviewed papers were supported by this grant [21, 26, 27, 29, 56, 67-69]. This grant was a primary source of support for the graduate education of K. Inderbitzen, now a C-DEBI Postdoctoral Fellow, and supported ten presentations. Clark: OCE05-50203, $89,100, 02/06–01/10 OCE-1031352: $185,622, 10/10-09/12 “Establishment and initial servicing of a three-dimensional, subseafloor, IODP observatory network in the northeastern Pacific Ocean." These projects focused on engineering development and construction of instrumentation in anticipation of IODP Exp. 327 and the subsequent analysis of samples retrieved during the tracer injection and during the 2011 R/V Atlantis cruise (AT18-07). These grants supported three undergraduate researchers and results were presented at an international meeting in Potsdam and at the 2009 Ocean Leadership “Scientific Ocean Drilling of Mid-Ocean Ridge and Ridge-Flank Settings” workshop and in two publication [2, 2a]. Cowen: MCB06-04014, $1,100,000: 3/1/2007 to 4/31/2012, “Collaborative Research: Microbial Ecology of Ocean Basement Aquifers: ODP Borehole Observatories” Cowen, Rappe, Amend and Glazer. This project developed the highly successful submersible-borne mobile pumping system (MPS) and an autonomous instrument sensor/sampler system (GeoMICROBE) to interface with CORK fluid delivery lines to obtain pristine samples from upper basaltic basement. The project yielded biogeochemistry and microbial diversity data, thermodynamic modeling, and metabolic rate experiments. This grant supported 1 MS thesis, 2 PhD dissertations, 10 undergrads, 7 graduate students and 3 postdocs, [1, 2, 2a, 24, 26, 44, 70-72]. Five K-12 teachers were involved with the ‘Teacher-at-Sea’ program. All personnel participated in UH ALI’I Summer Workshop for Middle & High School teachers and in UH Astrobiology School. Edwards OCE-0526285 (J. Bernhard, Woods Hole Oceanographic Institution, Co-PI) “Development and Testing of Materials Methods for In-situ Incubations and Subsurface Microbial Observatories at North Pond” (04/1/07 to 3/31/09; $ 244,310). This project developed methods for in-situ colonization and alteration experiments for boreholes and the seafloor and supported postdoctoral investigator Beth Orcutt, Modular experimental chambers were deployed in subsurface observatories on the Juan de Fuca Ridge flank, Costa Rica Margin, in the Nankai Trough, and on the Mid-Atlantic Ridge flank. This work has resulted in nine publications in print [1, 26, 27, 63, +73, 74, 76] with two EOS articles that incorporated elements of experimental subcrustal microbiology (Hayman et al., 2010; Humphris et al., 2011). Fisher: OCE-0727952, $190,653, 9/07-8/11, "Collaborative research: Large-scale, long-term, multi-directional, cross-hole experiments in the upper oceanic crust using a borehole observatory network." The primary goals of this project were to service subseafloor observatories and to prepare and deploy a suite of instrument systems for long-term experiments on the eastern flank of the JFR. Work included preparing data loggers for recording of seafloor subseafloor pressures, and a newly developed seafloor flow meter system based on an electrical induction sensor for use with a cross-hole hydrologic test. Additional work involved interpretation of thermal (survey) and subseafloor (observatory) data and modeling in support of hydrogeologic studies, including regional assessments of thermal and chemistry data around Dorado outcrop [1, 2, 2a, 22, 25, 27, 29, 45, 54, 56, 59, 63, 68, 73, 75] This grant provided partial support for two graduate and one undergraduate student and 20 presentations. Wheat: OCE-0727119, $171,712, 4/08-3/10 “Collaborative research: Large-scale, long-term, multi-directional, cross-hole experiments in the upper oceanic crust using a borehole observatory network”. This work focused on a 4-yr continuous geochemical fluid record from deep-sea boreholes using OsmoSamplers in a ridge flank hydrothermal system along the eastern flank of the Juan de Fuca Ridge. Systematic variations in chemical data constrain geochemical, microbial, and hydrologic processes within the upper basaltic crust. This grant supported thirteen peer-reviewed papers [1, 2, 2a, 22, 24-26, 27, 45, 60, 61, 63, 73-75], and numerous abstracts and presentations. C - Download 1.53 Mb. Share with your friends:
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