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doi:10.2204/iodp.sp.316.2007

Sampling and data sharing strategy

NanTroSEIZE Stage 1 expeditions are a single coordinated science program

To maximize the science return, the three Stage 1 expeditions will be implemented as a single science program with samples and data shared across all three expeditions. This presents unique opportunities and challenges to ensure overall NanTroSEIZE project success, individual expedition success, and realization of each individual participant's scientific objectives.

We have not finalized all of the details, processes, and mechanisms for sample and data sharing, but members of the management structure (IODP-MI, SAS, NT-PMT, Co-Chief Scientists, CDEX, and USIO) are committed to working with the scientific participants to ensure effective and efficient implementation of the overall science plan.

Three key points related to overall research planning are as follows:

1. Specialty Coordinators. Unlike traditional stand-alone ODP-IODP legs and expeditions, unusual amounts of coordination and collaboration must occur among science parties across the three Stage 1 expeditions. Specialty Coordinators will be responsible for facilitating these essential collaborations. The NT-PMT has identified six specific research areas that require special effort over the project's duration. These include (a) lithostratigraphy and sedimentary petrology, (b) structural geology, (c) geotechnical properties and hydrogeology, (d) geochemistry, (e) log-seismic integration, and (f) paleomagnetism and biostratigraphy. Specialty Coordinators will provide technical and scientific guidance to each science party and facilitate cross-expedition collaborations among the science parties to achieve NanTroSEIZE Stage 1 objectives.

2. Community samples. As usual, individual scientists will collect samples for shipboard analyses and their postcruise research. In addition, however, we intend to collect substantial numbers of "community" archive samples, especially whole-round (WR) cores. In some cases, these community samples will augment and/or provide redundancy for those requested by shipboard scientists. The goal is to preserve samples for a wide range of overall science objectives over the duration of the NanTroSEIZE project.

3. Sample clusters. To ensure achievement of Stage 1 and overall NanTroSEIZE scientific objectives, it will be essential to co-locate suites of essential data types. This must be done with appropriate and consistent sample spacing throughout each site's stratigraphic succession and across all Stage 1 sites.

Research plan proposals (sample and data requests)

Shipboard and shore-based researchers should refer to the IODP Sample, Data, and Obligations Policy (www.iodp.org/program-policies). This document outlines the policy for distributing IODP samples and data and defines the obligations that sample and data recipients incur.

A coordinated Stage 1 research plan covering all samples and data is required well in advance of the first expedition that is scheduled to start in September 2007. Scientists must submit their research plans using the Sample/Data Request form available at www.iodp.org/access-data. This will be required much earlier for the NanTroSEIZE Stage 1 expeditions to ensure coordination among the three Stage 1 expeditions. The coordinated Stage 1 research plan will be developed prior to the first NanTroSEIZE Stage 1 expedition with substantial involvement and interaction of Stage 1 expedition Co-Chief Scientists, science participants, and Specialty Coordinators. We expect all of the individual expedition participants to honor expedition-specific as well as cross-expedition objectives and priorities. Substantial collaboration and cooperation will be required.

Access to data and core samples for specific research purposes, both during each expedition and during the subsequent 1 y moratorium, must be approved by the Sample Allocation Committee (SAC) for that particular expedition. The moratorium for NanTroSEIZE Stage 1 will extend 1 y from the completion of the last of the three Stage 1 expeditions, or if a significant postcruise sampling party is required, 1 y following the completion of the sampling party.

The SAC is composed of the Co-Chief Scientists, Staff Scientist, and IODP Curator on shore, and curatorial representatives in place of the curator on board ship. For NanTroSEIZE Stage 1, there is a SAC for each expedition. All three SACs will contribute to the overall coordinated research planning effort. The six Specialty Coordinators will also contribute to this process as project-wide representatives of their respective disciplines.

Based on research (sample and data) requests submitted, the SAC will work with the scientific party, other Stage 1 SACs, and Specialty Coordinators to formulate a formal expedition-specific sampling and data-sharing plan for shipboard and postcruise activities. This plan will be subject to modification depending upon the actual material/data recovered and collaborations that may evolve between scientists before and during the Stage 1 expeditions. Modifications to the sampling plan during the expedition require the approval of the SAC.

All sample frequencies and sizes must be justified on a scientific basis and will depend on core recovery, the full spectrum of other requests, the expedition objectives, and project-wide NanTroSEIZE objectives. Success will require substantial amounts of cross-expedition collaboration, integration of complementary data sets, and consistent methods of analysis.

When critical intervals are recovered, there may be considerable demand for samples from a limited amount of cored material. These intervals (e.g., highly deformed fault zone) may require special handling, a higher sampling density, reduced sample size, or continuous core sampling for a set of particular high-priority research objectives. The SAC may require an additional formal sampling plan before critical intervals are sampled.

All sampling to acquire ephemeral data types or achieve essential sample preservation will be conducted during the expedition. Sampling for individual scientists postcruise research may be conducted during the expedition or may be deferred to postcruise. The working plan will be based on the coordinated Stage 1 research plan to be developed prior to the first Stage 1 expedition. Following Expedition 316 and all NanTroSEIZE Stage 1 expeditions, cores will be delivered to the IODP Core Repository at Kochi University, Japan.

Cruise-specific sampling

The unique nature of the NanTroSEIZE project requires some adaptation of existing IODP policies and procedures. As scientists develop their individual research plans for core samples and data, they should refer to this expedition's scientific objectives (see above), the other Stage 1 expeditions, as well as the overarching Stage 1 Scientific Prospectus (Tobin and Kinoshita, 2006a).

We anticipate an extensive sampling program to achieve research objectives within most disciplines. When possible, our goal will be to make as many measurements as possible on common (or nearly co-located) samples, thus reducing the amount of material removed from the core and maximizing our ability to correlate different data types. These sample clusters (e.g., pore water, carbon carbonate, moisture and density, bulk X-ray diffraction, clay X-ray diffraction, and bulk chemistry) will also improve our ability to complete routine complementary postcruise analyses. Substantial whole-round core sampling will be conducted to obtain appropriate samples for ephemeral shipboard analyses and to appropriately preserve samples for postcruise research. Such whole-round samples are especially important for geotechnical and rock mechanical tests (e.g., permeability, consolidation, triaxial, ring-shear, etc.). Because different laboratories employ different protocols and have different capabilities and limitations (e.g., elevated temperature, stress ranges, and strain rates), there are no rigorous standardized approaches for many of the critical measurements. This, combined with a need for comprehensive characterization of core materials over the broadest possible range of experimental conditions, requires a coordinated sampling approach. Experience further shows that it is impossible to identify all of the critical sampling intervals before the cores are split. Therefore, not only will whole-round samples be extracted for individual scientist's research, we will also to build a community archive. The community whole-round specimens will be stored at the repository (Kochi) and released to scientists only after they file appropriate sample requests. These samples will be used primarily to ensure that there are no critical gaps in sample characterization with respect to both spatial sample distribution and scientific data types generated, for interlaboratory calibration, redundancy, and quality assurance/quality control (QA/QC).

Community labs for postexpedition analyses

Whereas many analyses can and will be conducted at sea, others require state-of-the-art instrumentation that is only available onshore. We are particularly concerned about stable isotopic measurements that depend upon dedicated instruments not found at all universities and government laboratories. For example, we expect to collect pore waters to measure at least Sr, B, Li, O, H, Cl, and C stable isotopic compositions. It is doubtful that any individual scientist has the onsite capability to make all of the measurements listed above. Issues regarding QA/QC become significant. To get the most consistent and reliable data for all Stage 1 expeditions, the NT-PMT has proposed that all samples for each category of geochemical analysis go to a single laboratory. Several laboratories (to be determined) will have to be involved. For example, one laboratory might measure O, H, and C isotopes, whereas another might measure Cl isotopes or Li. The choice of a particular laboratory (and analytical technique) will be reached by consensus of the inorganic geochemists who sail on the Stage 1 coring expeditions, mediated by the Specialty Coordinator in geochemistry and approved by the expedition SAC. We anticipate that data generated from each laboratory will be shared by all members of the Stage 1 scientific party for use as defined by the approved research plans.

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