230 300 ■ 



t' I I i' 

 1,200 2,400 ft 



GALVESTON ISLAND 



San Luis Pass Bridge 



San Luis Inlet Statigraphy 



San Luis Island 



Galveston Island 



20 

 10 



MSL 



■50 



(ft) 



-150 



12 3 4 5 6 7 8 loL-^"^ \\ |2 |3 14 15 16 17 



t,J,>=^ 



1,200 



2,400 



3,600 



(ft) 



4,800 



6,000 



7,200 



-20 (m) 



-30 



8,400 



I poo 



1,500 



2,000 



2.500 



(m) 



cm 



LEGEND 



Voderatley sorted 

 »«ry fine lo fine sanrf 

 ond >ilty sand 



Sllty sondy shell 

 gravel 



1 Stiff tan and groy 

 cloy (pre-Holocene 

 age) 



Soft Holocene cloy 



Figure 20. Quaternary stratigraphy at San Luis Pass based 

 on interpretations of descriptive logs of 16 

 (boring 9 not taken) borings. The Pleistocene 

 surface in this profile correlates well with 

 offshore data and is used to define the lower 

 boundary for Borrow Area D. 



47 



