APPENDIX B 



SEDIMENT SAMPLE CARDING TO FACILITATE COMPARATIVE CORRELATION 

 (from an unpublished CERC Coastal Engineering Technical 

 Note, TN-VI-2, Sept. 1979) 



PROBLEM; Develop a technique for rapid visual analysis of a large number of 

 sediment samples as a preliminary step in correlation. 



BACKGROUND ; Use of descriptive logs for comparative visual analysis of sedi- 

 ment from cores and borings is rarely as satisfactory as firsthand study of 

 the actual material. This is true because subtle visual properties which 

 cannot be fully described are often important in showing relationships. Where 

 large numbers of samples are being analyzed, comparison of the sediments in 

 their original containers is cumbersome and requires considerable space for 

 layout. In addition the analyst, being unable to scan more than a few samples 

 at a time, is less efficient in perceiving relationships. A useful expedient 

 for making preliminary comparative analysis of a large number of samples is 

 to glue small representative subsamples on illustration board cards. 



The use of carded samples cannot, of course, eliminate the need for more 

 complete work with the whole sample and for more sophisticated forms of 

 analysis. It has been found, however, that carded samples are very useful 

 during preliminary analysis and correlation, and in providing the basis for 

 selection of representative samples for more detailed study. 



PROCEDURE ; The card stock used for the sample cards is white illustration 

 board readily available from commercial art and drafting supply companies. 

 Almost any size card can be used, depending upon the number of samples per 

 core or boring. A 4- by 8-inch card is satisfactory for the usual number of 

 samples per core. 



Subsamples are mounted in stratigraphic order down the left side of the 

 card in the following manner: A small quantity of all-purpose white glue is 

 placed on the card in the appropriate position along the left side and spread 

 over an area approximately 1 inch in diameter and having a thickness of approxi- 

 mately 0.5 millimeter. A small representative quantity of each sample is then 

 placed evenly over the glue area. Upon drying the glue forms a relatively 

 transparent matrix cementing the grains together. Each sample in turn is thus 

 mounted down the left side of the card. After drying, the card should be 

 lightly tapped on edge to remove excess loose material. As samples are mounted, 

 information such as core designation, location, and sample interval can be 

 entered on the right side of the card (see sample card in Fig. B-1) . Small 

 shells, pebbles and possible artifacts, if included in a sample, can also be 

 mounted if the glue layer is made somewhat thicker than for the more normal 

 sand-size material. Occurrence of large shell valves, pebbles, or peats in the 

 core can be noted on the right side of the card at the corresponding sample 

 interval. 



Filled core sample cards are stored in boxes constructed of 1/4-inch ply- 

 wood and 1-inch pine board. Slots 1/2-inch deep are made on one side of the 

 pine board at 1/2-inch intervals using a cutoff saw. The pine material is 

 used for the sides of the box with the slotted sides facing inward. The cards 

 can then be easily slipped into slots, numbered, and stored according to core 

 number sequence . 



