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Minutes 1998 Curators of Marine Geological Samples Meeting

CORE-DESCRIBING PROCEDURES

Guy Rothwell led a discussion on improving and standardizing core-describing procedures, especially as related to improving smear-slide descriptions. Paula Worstell submitted a sediment classification scheme based upon sediment grain-size and constituents as determined (mostly) from smear-slide inspection.

SMEAR-SLIDES

Guy Rothwell noted that smear-slide analysis is a qualitative method which constitutes "the FIRST, and often, ONLY look at (the sedimentological properties) of the core." Smear-slides are quickly and easily prepared, and, because their preparation requires so little material, are virtually non-destructive. The information gained relative to time spent is very high making smear-slide analysis an excellent tool for basic (sediment) core description. He noted a marked deterioration in core descriptions between earlier and recent ocean-drilling/coring cruises saying, "core describers are a dying breed and principal investigators or students who are often called upon to do the descriptions, are not trained to a consistent standard."

In order to increase the RELIABILITY AND REPRODUCIBILITY of smear-slide data, Rothwell called upon the curatorial community to reach a common agreement regarding sediment classification, means of collecting and reporting data (interpreting weight or percentage of components, reporting absolute abundance of components versus defined relative abundances, improving recognition of sediment components.)

As a means to improving the use and validity of smear-slide data, Rothwell suggested curators collaborate to develop REFERENCE COLLECTIONS and produce CD-ROM/Educational WebSite focussing upon training in core-describing, smear-slide techniques.

The smear-slide reference collection might contain, in addition to examples of common components, examples of unusual forms, and also STANDARDS with various grain-size percentages, weight percentages, representative environments, and index fossils. Collections of slide photomicrographs would further enhance the reference collection.

The assembled group fully endorsed both concepts (reference collections and educational CD-ROM), some noting that the education web site development would allow for "dynamic change," and general user accessibility. The CD-ROM would be made available to repositories, and ship-based labs.

ACTION: Guy Rothwell will "take the lead" in developing a (sediment) core-describing multi-platform CD-ROM and web site, focussing on employment of smear-slide analysis techniques. Others agreed to provide ideas and images of appropriate slide views. Rothwell hopes to have a "pilot" CD-ROM for viewing at the next Curators' meeting.

ACTION: Members of the group agreed to exchange slides and other materials useful in developing standardized reference collections.

(Guy Rothwell and Paula Worstell distributed smear-slides of some interesting components to the assembled group to initiate the reference collection exchange.)

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