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doi:10.2204/iodp.sp.325.2009 AppendixGreat Barrier Reef Environmental Change ESO sampling and measurement planThis plan was discussed and agreed on during various meetings and subsequent communications with the Co-Chief Scientists. Nevertheless, this plan is subject to amendment according to the scientific needs and interests of the Scientific Party or operational constraints. The most pressing operational constraint during the offshore period is likely to be space, with containers being located on both a mezzanine and deck level. In order to minimize core transit between containers and up/down stairs on the platform, the core flow scheme below has been devised. Offshore sampling and analysis
Please see www.marum.de/en/ Core curationThere will be a core curation laboratory container onboard the drilling vessel, supervised by the Chief Curator. A second Curator will cover the opposite shift. The Curators will have delegated responsibility in the absence of the ESO Curation Manager and IODP Curator Dr. Ursula Röhl. A sufficient number of core storage containers will be on the drilling vessel. There will be no splitting of the cores at sea, as it will be more efficient to carry out most of the scientific analysis during the OSP in Bremen. As the cores will be collected in a plastic liner or a metal "spoon" liner (before being transferred to a plastic liner on the drill floor), the usual IODP curation procedures will be followed (please refer to www.marum.de/en/Core_curation.html). The core will be cut on board into 1.5 m lengths and curated. It has been noted that it is important to store corals in dry conditions to avoid growth of fungi and bacteria that can develop in coral skeletons, resulting in the strong possibility of alteration to the original geochemical signals. Lithologic and macropaleontologic descriptionCore catcher samples will be collected, split, and labeled and the working half handed over for lithological and macropaleontological description. If no core catcher is collected, a sample from the lower end of the section will be taken for shipboard lithologic and macropaleontologic analysis. If the lower end of the core is a massive coral, no sample will be cut off the core. Offshore core flowFor details of the offshore core flow, see Figure AF1. Inorganic geochemistryNo major mud sequences are expected to be encountered at the proposed drill sites. Site survey cruises indicate that limestones and unconsolidated sands will be the dominant sediments expected. However, if suitable material is recovered, pore water sampling will be conducted for fluid chemistry/circulation studies. In this case, pore water should be extracted immediately from a core sample, and ephemeral properties such as salinity, alkalinity, and ammonia will be analyzed immediately (www.marum.de/en/Interstitial_pore_waters_IW.html). Depending on the parameter, the interstitial water sample might be specially treated in order to conserve it for later analyses. MicrobiologySampling for microbiology studies will be undertaken if IODP implements STP Recommendation 0807-12, "Microbiology Routine Sampling for Frozen Preservation," or if specific samples are requested by microbiologist(s) from the Science Party. If samples for microbiology are taken, they will be taken immediately in the field under the most sterile conditions possible. It will be important to know if microbes from the drilling fluids have entered the cavities during drilling. Ideally, fluorescent microspheres should be used during drilling, but they will not be used during Expedition 325 for environmental reasons. Results should be interpreted with care, as contamination may occur during drilling and any microbial material found may not be in situ. To limit the effects of contamination, samples will be washed with sterile seawater and only the attached microbes will be considered for further activity measurements (which includes typically >99% of the total biomass). Depending on sample requests received and the implementation of microbiology during Expedition 325, potential studies may include
Offshore petrophysics measurementsCore loggingCores will be logged on the drilling vessel in a modified 20 ft container, housing a single MSCL track comprising one magnetic susceptibility loop, gamma density, P-wave velocity, and electrical resistivity sensors (www.marum.de/en/Physical_Properties_3.html). The single core-logger system will include a full spares kit. All temperature-equilibrated core log data acquired at sea will provide QA/QC checks when compared to repeat measurements planned for Bremen. Downhole logging
The following is a generic list of minimum and additional tools, based on formation properties discussed with proponents:
Onshore sampling and analysisOnshore core flowFor details of the offshore core flow, see Figure AF2. LocationAfter due consideration, it has been decided that there will be no splitting of the cores at sea. The OSP will be undertaken at the IODP Core Repository and laboratory at Bremen University in combination with access to the laboratories at MARUM and the Department of Geosciences. Planned analysis and available facilitiesThe following facilities will be available for the expedition scientists at the Bremen IODP Core Repository (please also refer to the online tutorial at www.marum.de/en/Onshore_Science_Party_OSP.html). Note that it is not considered prudent to transport all these facilities onto a drilling vessel:
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