Part II
SAMPLING STRATEGY

New sampling guidelines specify that formal, leg specific sampling strategies be prepared by the Sample Allocation Committee (SAC = co-chiefs, staff scientist, and ODP curator onshore and curatorial representative on board ship). Modification of the strategy during the leg must be approved by the curatorial representative on board ship, the co-chiefs, and staff scientist. The sampling strategy presented here conforms with the new guidelines and will be refined as sample requests are evaluated and considered by the shipboard party prior to arrival at each site.

Minimum Permanent Archive
The minimum permanent archive will be the standard archive half of each core.

Sample Limit
Shipboard scientists may nominally expect to obtain 100 samples up to 15 cm3 in size. Additional samples may be obtained upon written request onshore soon after the cores return to the ODP repository. The guidelines will be adjusted upward or downward by the shipboard SAC, depending on the penetration and recovery during Leg 179. All sample requests of whatever number and volume must be justified in writing using the standard sample request form and approved by the SAC.

Large Samples
Samples larger than 15 cm3 may be obtained with the approval of the SAC, but shall be considered the equivalent of multiple samples in partial or complete increments of 15 cm3. Request for large samples must be specified on the sample request form except where there are detailed stratigraphic studies of specific intervals of the core, in which case they must be approved on an individual basis for each interval by the co-chief scientists.

Redundancy of Studies
Some redundancy of measurement is unavoidable, but minimizing the redundance of measurements among the shipboard party and identified shore-based collaborators will be a factor in evaluating sample requests. Request for independent shore-based studies that substantially replicate the intent and measurements of shipboard participants will require the approval of both the shipboard investigators and the SAC.

Shipboard Samples and Data
Following core labeling, measurement of nondestructive properties, and splitting, samples will be selected from core working halves by members of the shipboard party for routine measurement of physical and magnetic properties, bulk chemical analyses by X-ray fluorescence (XRF) and carbon-nitrogen-sulfur (CHNS) analyzer, and X-ray diffraction as necessary. Polished thin sections will be prepared for identification of minerals, determination of mineral modes by point counting, and studies of texture and fabric.

A suite of samples will be identified for full measurement characterization. At approximately 9.5 m intervals (once per full core), slabs measuring 10x6x1.5 cm, with previously sampled central minicore, will be cut to be used for all shipboard measurements, then subdivided and split appropriately for further shipboard geochemical, mineralogic, and petrographic studies. Where necessary to avoid or include features like veins and alteration, quarter cores may be taken instead of slabs.

Data from all shipboard studies, regardless of the method or observer (including core descriptions and measurements) are the property of the entire shipboard party and may be used exclusively by them in publication and for preparation of manuscripts with proper citation in the Initial Reports volume up until the publication of the Initial Reports volume or 12 months postcruise, whichever is later.

Shipboard Thin Sections
Shipboard thin sections will be selected from representative sections of the core. These sections will remain the property of ODP and may be checked out after the cruise.

Critical Intervals
Short intervals of unusual scientific interests (e.g., veins, ores, 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.


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