

- 











- 









500 



- 









400 



- 





O 



° °* ° 



° § O 



300 



- 







DO ^ SUBOPBITAL 

 o D. RIPPLES 



DO g 



















& 



200 



— 









A/D'/' 











*',*•' 



(em'/'> 





ORBITAL 







+ .. i ;.* 



(00 



— 



RIPPLES 



°° 





90 



- 









80 



- 





o 



.* .,'••■ '• ♦. • 



70 



- 





••■ 



. ° * %*%* -it* **■ t.^ '.. 



60 

 60 



- 



a 



* 

 * 



A NOR BIT AL RIPPLES 



40 



" 









30 



- 



° X 



X 





. .069 -.126 mm 

 * .126 - .177 



20 





1 1 



1 1 ( t t I 1 



> .178 - .250 

 A .26) - .393 

 o .354 . .600 

 a .601 - .707 

 O 708-1.000 



1 1 1 1 1 1 r 1 1 L^— 







800 300 



400 500 1 70019001 



2000 3000 4000 5000 lOflOO 







600 BOO 1000 



d„/D 



Figure 14. Classification of symmetric and reversing ripples based on the ratio of ripple 

 length to square root of grain diameter (;\./D^ ) and ratio of orbital diameter to 

 grain diameter (do/D) (after Clifton (1976)) based on data from Inman (1957) 

 and Dingier (1974)) 



b. Suborbital ripples, which form under longer period waves and have 

 d^/D ratios between 2,000 and 5,000 (wavelength increases with 

 larger grain size but decreases with increasing orbital diameter). 



c. Anorbital ripples, which are associated with waves of very large 

 orbital diameter and have dJD ratios greater than 5,000 

 (wavelength depends on grain size and is independent of orbital 

 diameter). 



Reversing ripples, which are considered asymmetrical, have do/D ratios 

 between 6,500 and 13,000 (Inman 1957). 



In comparing symmetrical and asymmetrical wave ripple size, Clifton 

 (1976) states that symmetrical wave ripples form where maximum bottom 

 orbital velocity is less than 1 cm/sec, while asymmetrical wave ripples 

 form when maximum bottom orbital velocity is greater than 5 cm/sec. 



52 



Chapter 4 Sedimentary Features/Stratigraphy of the Inner Shelf 



