T.M. No. 48 - August 1954 



Sand Movement by Waves by Theodore Scott 



A series of two-dimensional experiments were carried out in a 

 laboratory wave flume using waves of high and low steepness ratios 

 to investigate the movement of sand along the bottom. Results are 

 primarily on the effect of long and short period waves on beach and 

 bar formation and onshore-offshore transport of material. Importance 

 of relative amplitudes of vertical and horizontal components of 

 orbital wave motion on sand movement and bottom ripple formation is 

 discussed. Information is presented on the mechanics of ripple 

 formation and their relation to onshore-offshore movement. 



T.M. No. 49 - August 1954 



Bore Hole Studies of the Naturally Impounded Fill at Santa Barbara , 

 Ca I ifornia by Part<er D. Trask and Theodore Scott 



A ser ies of 7 bore-ho I es were dr i I I ed in the accumu I ated fill 

 area west of the breakwater and the cores analyzed. The fill area 

 overlays areas formerly covered by sea water and thus information 

 was obtained as to how sand accumulates both offshore and on the 

 beach. Analysis and results are presented. 



T.M. No. 50 - August 1954 



Statistical Significance of Beach Sampling Methods by W. C. Krumbein 



Beach sampling methods in terms of statistical principles are 

 reviewed for the purpose of suggesting tentative plans for improving 

 the representativeness in samples. Statistical methods used are 

 discussed. Results of the study indicate no radical revisions of 

 current sampling procedures are needed, but recognition of explicit 

 design elements in the sampling plan can result in greater reliability 

 of the data for comparable expenditure of time and effort. 



T. M. No. 51 - October 1954 



Generation of Wind Waves Over a Shal low Bottom by C. L. Bretschneider 



A method is presented for predicting properties of waves gene- 

 rated in shallow water. The method is essentially one of successive 

 approximations in which energy is added to the wave due to wind stress 

 and subtracted from the wave due to bottom friction and percolation. 

 The development utilizes a relationship for deepwater wave generation 

 devised by Sverdrup and Munk and revised by Bretschneider, with the 

 theory of wave energy losses in shal low water devised by Putnam and 

 Johnson and revised by Bretschneider and Reid. 



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