offshore distance (station) , alongshore distance (range) , and elevation 

 at fixed times (Table 2) during the experiment. The CONPLT method (see 

 Vol. I) for presenting the data involves fixing the alongshore distance 

 by selecting data from given range and analyzing the surveys along that 

 range. The surveyed distance-elevation pairs along that range are used 

 to obtain the interpolated position of equally spaced depths; i.e., -0.1, 

 -0.2, and -0.3 on the hypothetical profile in Figure 4(a). These contour 

 positions from each survey are then plotted against time (Fig. 4,b) . 



A horizontal line in Figure 4(b) represents no change in contour posi- 

 tion. An upward-sloping line indicates landward movement of contour 

 position (i.e., erosion) ; a downward-sloping line indicates deposition. 

 The slope of a line indicates the horizontal rate of erosion or deposi- 

 tion at that elevation. The three x's at time t2 (Fig. 4,b) indicate 

 multiple contour positions at elevation -0.2 which is shown by the inter- 

 section of the dashline with profile t2 in Figure 4{a) . 



Three types of contour movement plots included in this study are: 



(a) Tlie seawardmost intercepts along one range for selected 

 depths; 



(b) the seawardmost intercepts for one selected depth along 

 all ranges; and 



(c) all contour intercepts including multiple intercepts 

 along one range, for up to 12 selected depths. 



The coordinate system used for the contour movement plots is shown in 

 Figure 5. The following elevations are referred to in the discussion 

 that follows: 0.1 foot (3.0 centimeters), 0.2 foot (6.1 centimeters), 

 0.3 foot (9.1 centimeters), 0.4 foot (12.2 centimeters), 0.5 foot (15.2 

 centimeters), 0.6 foot (18.3 centimeters), 0.7 foot (21.3 centimeters), 

 0.8 foot (24.4 centimeters), 0.9 foot (27.4 centimeters), 1.0 foot (30.5 

 centimeters), 1.1 feet (33.5 centimeters), 1.2 feet (36.6 centimeters), 

 1.3 feet (39.6 centimeters), 1.4 feet (42.7 centimeters), 2.1 feet (64.0 

 centimeters) . 



b. Profile Zones . Definitions of coastal engineering terms used in 

 LEBS reports conform to Allen (1972) and the Shore Protection Manual 

 (SPM) (U.S. Army, Corps of Engineers, Coastal Engineering Research Center, 

 1975) . For the profiles zones in this study, the boundary between the 

 foreshore and inshore zones is defined at elevation -0.2 foot. 



The seaward edge of the inshore zone is defined as extending through 

 the breaker zone. The boundary between the inshore and offshore zones 

 for this experiment is at elevation -0.8 foot. 



A definition sketch of the profile zones is shown in Figure 6. Early 

 profiles (solid line in Fig. 6) had a steep foreshore, a long flat inshore, 

 and a slightly steeper (than 0.05) offshore. Later profiles (broken line 



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