(b) Site 1 Fan . Site I fan has been the primary research site 

 for study of the revegetation proceas on washovers. The February 1978 storm 

 deposited large quantities of sand in this area, burying the developing dune 

 line on the previous fan (Fig. 11). During the February northeaster, the fan 

 center was displaced southward due to storm wave approach and previous back, 

 barrier topography (Fig. 15), and 30- to 40-knot winds from the northeast 

 drove overwash surges to the southwest. A washover created in 1938, north of 

 site 1, was only marginally evident in 1978; however, the slight increase in 

 elevation resulting from the washover caused swashes to be deflected to the 

 south. 



A three-dimensional plot was developed from elevation data collected 

 before and after the storra at the 5- by 5-meter grid at site 1 fan (Fig. 18). 

 The greatest sand deposition (85 centimeters) occurred near the center of the 

 fan, located at the southeast corner of site 1 fan plot (Figs. 15 and 18; 

 60S to 0W) . The northwest corner of the site was not affected by the washover 

 deposit (Fig. 15; OS to 50W) . Mean sand deposition for site 1 fan was 0.62 

 meter (o «■ 0.35 meter). The elevation range increased from 1.01 meters in 

 1977 to 1.79 meters in 1978, reflecting large deposits of sand in the center 

 of the fan and no sand deposition at the edge of the plot. Although some 

 dune vegetation had been present on the washover fan in 1977, site 1 fan was 

 predominantly a salt marsh with very little topographic relief. The effect 

 of overwash In this area Increased topographic Irregularities (1977, a » 0.24 

 meter; 1978, o - 0.49 meter), partly because the area had been a salt marsh 

 and partly because site 1 fan was located at the edge of the washover. 



(2) Site 2 Washover . Site 2 overwashed during both the January and 

 February 1978 northeasters. The meandering throat present during the creation 

 of the washover in fall 1976 was straightened by the January 1978 Btorm. The 

 February northeaster completely eliminated the dunes seaward of site 2, en- 

 gulfing the area In a massive washover. Pits dug In the substrate showed that 

 approximately 0.20 to 0.50 meter of sand had been deposited over the salt 

 mar9h. Surflclal drift material was not present after the storm. A lag layer 

 of shells deposited during the storm was present throughout the area. 



Site 2 continued to overwash throughout February and March 1978 and during 

 the spring tides of April, May, and June, periodically exposing aad covering 

 the vegetation present during 1977. Plants did not recover from overwash 

 burial, and colonization from drift material did not take place during the 

 growing season at site 2. Tne fan has, therefore, remained active in terras of 

 sediment transport (overwash and aeoltan) and has been continually subject to 

 saltwater flooding. Neither elevation surveys nor vegetation samplings were 

 continued at this site after the February 1978 northeaster. 



(3) Site 3 Washover. Site 3 has perhaps proved to be the most inter- 

 eating area on Nauset Spit-Easthara. This site was established in June 1977 

 because the dune profile was very low and it appeared to be a location for 

 possible future overwash activity. In 1977 a small breach at site 3 and an 

 adjacent small breach in the foredune were the only breaks in the otherwise 

 continuous dune line in the area. Storms on 10 May and 10 June 1977 eroded 

 a small channel Into the dunes, flooding and killing any dune vegetation. 

 Overwash did not penetrate the back of the dune line and very little sand was 

 eroded or deposited. The February 1978 northeaster penetrated the dune line 

 In the same position, eroding a slightly larger channel. The dunes in the 

 area remained intact as overwash surges passed over these low dunes without 

 causing significant erosion. 



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