Figure 9. Streamer traps deployed in a TSM run 



the water and brought to shore (Figure 10) , and collected sand was washed from 

 the streamers with seawater into small patches of filter cloth. The sand 

 sample and cloth (of known weight when wet) were weighed in the drip-free 

 condition (Kraus and Nakashima 1986) . Samples from all traps from one run per 

 day were retained for drying and grain size analysis in the laboratory. The 

 dry weights obtained allowed calibration of the drip-free to dry weight 

 conversion factor. Deployment of trap pairs continued (denoted by the symbols 

 T5 through T8 in Figure 2) for data collection periods from 23 to 84 min in 

 length. 



25. Between experiment runs, the trapped sand weights were plotted to 

 understand qualitative aspects of the transport conditions and to design the 

 next series of runs, such as positioning of traps and length of temporal 

 sampling. For example, from inspection of the transport rate distribution 

 through the water column, a supporting cross-bar on the trap frame was found 

 to partially block sand transport into the second streamer above the bed. 

 During succeeding data collection, the second streamer was positioned away 

 from the cross-bar, eliminating the problem. The capability to analyze the 



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