CONTENTS 



FIGURES-Continued 



Page 



3 Gross geomorphic divisions of the Boston area 15 



4 Generalized bathymetric chart of the study area 20 



5 Geomorphic subdivisions of the study area 21 



6 Seismic reflection profile showing reflection units 25 



7 Smoothing procedure used to generalize acoustic basement 



surface 26 



8 Contours on the acoustic basement 27 



9 Section of seismic reflection profile showing transparent 



reflection unit 28 



10 Photos of sand from the study area 32 



11 Graphic-size distribution curves for sand samples 33 



12 Photos of gravelly sediment from the study area 35 



13 Map showing surface sediment distribution 37 



14 Location of sand deposits 43 



15 Bottom topography, Cat Island sand deposit 45 



16 Seismic reflection profile of the Cat Island sand 



deposit 46 



17 Bottom topography, Nahant sand deposit 49 



18 Seismic reflection profile, Naliant sand deposit 50 



19 Bottom topography, Nantasket East sand deposit . 51 



20 Seismic reflection profile, Nantasket East sand deposit .... 52 



21 Bottom topography, Nantasket Center sand deposit 54 



22 Seismic reflection profile, Nantasket Center sand deposit ... 55 



23 Bottom topography, Nantasket West sand deposit 56 



24 Seismic reflection profile, Nantasket West sand deposit .... 57 



