Solve the Sediment Puzzle

You have to find a number of 15 digits by answering the following 15 questions.
This number of 15 digits represents the coordinates (position of the pointer of
Google Earth) of a very famous beach.

Find the name of the beach and send this name to

1.  How many main groups of sediment size does the American
     Geophysical Union Scale have for sediments between 0 and 64 mm?
     a) 2                b) 4                  c) 8

2.  What is the annual consumption of sand (in tons/year)
     per person per year in Northwestern Europe?                  
     a) 1                b) 3                 c) 9

3.  How many novels did R.A. Bagnold write?                         
     a) 1                b) 2                 c) 3

4.  How many millions of sand grains of 0.85 mm can be put
     in a bottle of 1 liter?
     a) 2                b) 5                 c) 9

5.  How many months does it take for a silt particle to travel
     along the Rhine river from the origin to the sea assuming
     a mean flow of about 0.5 m/s?                                           
     a) 1                b) 4                  c) 8

6.  What is the filling time (in months) of a channel with area
     of 500 m2 by a cross-current with a transport rate of
     0.1 kg/s/m? 
     a) 1                 b) 3                 c) 7

7.  What is the fall velocity (in cm/s) of a sand particle of
     0.35 mm in water of 20 degrees Celsius?                         
     a) 1                 b) 5                 c) 8

8.  What is the favourite number of mother nature?                
     a) 1                 b) 3                  c) 7

9. What is the net sediment transport in the case of an onshore
     asymmetry bed load transport of  1 kg/s/m, a return flow
     of 0.25 m/s, a depth-averaged concentration of 2 kg/m3
     and a water depth of 2 m?
      a) 0                 b) 1                 c) 2

10. What is the migration velocity of a ripple (in m/hour) with a height of 0.1 m
       and a length of 1 m and a bed load transport rate of 0.1 kg/s/m?
       a) 1                b) 5                 c) 9

11. What is the power of velocity in the sediment transport relationship?
        a) 1               b) 3                 c) 6  

12. What is the critical velocity ( threshold) velocity (in m/s) of a sediment
       particle of 5 mm?
       a) 1                b) 2                 c) 3

13.  What is the minimum number of points over the depth to obtain an accurate
       measurement of suspended sand transport?
       a) 1                b) 3                  c) 9

14. How many groynes with a length of 100 m would you use to stabilize a beach
       with a length of 1 km?
       a) 1                b) 3                 c) 7

15.  What is roughly the dredging price (in dollars per m3) of sand in the case of
       a hopper dredger?
       a) 1                b) 3                 c) 8

Members of the elite International Sediment Club (ISC)
President:            Leo van Rijn
Vice-President:    Richard Soulsby

Matthieu Cartigny, The Netherlands
Frank Krijnen, The Netherlands
Maarten van Ormondt, The Netherlands
Bas van Maren, The Netherlands
Christophe Briere, France
Andrew Ashton, USA
Pedro Abel Basilie, Argentina
Yorian van Leeuwen; The Netherlands
Gerwin Stam; The Netherlands
Jesper Schoen; The netherlands
Russ Lowgren; USA
Steven Luger; South Africa