Shipboard Samples and Data Acquisition
Biological samples: As many as four samples per hole will be removed to a sterile environment immediately after opening each basalt core barrel. Procedures for this removal have not yet been decided. Ideal samples will be intact core sections, 10-50 cm in length, with basaltic glass attached at one end. Samples will be cleaned in a sterile environment, then a micro core up to 10 cm in length will be removed from the axis of the core. As quickly as possible, the remaining core will be split and returned to the core storage trays. As soon as possible after shore-based extraction procedures are complete, these samples will be made available for other types of study.
Quick Response Samples: As soon as possible after core recovery, three to five samples per hole will be removed for ICP analysis for Ba and other key indicator elements. Quick analysis will be critical, as these results will determine the next site to be drilled.
Routine Samples: Following core labeling, measurement of nondestructive properties, and core splitting, samples will be selected from working-half cores (approximately one to two samples per 9.5 m of core, or one from each major flow unit) by members of the shipboard party for routine measurement of physical and magnetic properties, bulk chemical analyses by X-ray fluorescence, carbon-nitrogen-sulfur (CNS) analyzer. If necessary, X-ray diffraction samples and polished thin sections of these samples will be prepared for identification of minerals, determination of mineral modes, and studies of texture and fabric.
Sampling for Shore-Based Studies
As a general guideline, shipboard scientists may obtain five to ten whole-rock samples per hole, as many as to ~100 samples for the leg. Samples may be up to 15 cc in size. In special cases, additional or larger samples may be obtained with the approval of the Sample Allocation Committee (SAC), which is composed of the co-chiefs, the staff scientist, the shipboard curatorial representative, and the ODP curator.
Glass samples are expected to be in high demand, and sampling strategies that emphasize cooperation will be encouraged. In general, individuals should expect to receive no more than 1 g of glass from any single layer, but special cases and strategies that maximize scientific return will be evaluated by the SAC.
Other short intervals of unusual scientific interest (e.g., veins, ores, and dikes) may require a higher sampling density, reduced sample size, continuous core sampling by a single investigator, or sampling techniques not available on board ship. These will be identified during the core description process, and the sampling protocol will be established by the interested scientists and shipboard SAC.
In all cases, to minimize the time and effort required for sampling and to maximize scientific return, we encourage sampling consortia involving researchers with complementary expertise. Sample size will depend on need as well as the number of investigators in the group. Additional samples may be requested in writing for distribution soon after the cores return to the ODP repository.
Redundancy of Studies
Some redundancy of measurement is unavoidable, but minimizing the redundancy of measurements among the shipboard party and identified shore-based collaborators will be a factor in evaluating sample requests. Requests from independent shore-based investigators that substantially replicate the intent and measurements of shipboard participants will require the approval of both the shipboard investigators and the SAC.
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