Soft sediments and granulometry

Small stones

less than 5 % of fine particles, more than 50% of pebbles + shells

Gravel

less than 5 % of fine particles, less than 50 % of pebbles + shells, median larger than 2 mm

Muddy heterogeneous sediment

more than 5 % of fine, median larger than 500 μm, high percentage of pebbles or shells

Coarse sand

less than 5 % of fine particles, more than 50% of sand + fine particles, median smaller than 2 mm

Heterogeneous muddy sand

fine particles between 10 and 30 %, sand, coarse sand and gravel between 50 and 80 %

Medium sand

about 0% of fine particles, fraction larger than 2 mm < 15%, median between 315 and 800 μm

Fine sand

less than 5 % of fine particles, fraction larger than 2 mm < 15 %,  median smaller than 250 μm

Fine sand with more or less mud

5 to 25 % of fine particles < 63 μm

Sandy mud

25 to 75 % fine particles < 63 μm

Mud

more than 75 % of fine particles < 63 μm

Grain size

&phi Unit

Blocks

more than10 cm

Pebbles - shells

more than2 cm

Coarse gravel

between 1 - 2 cm

Medium gravel

between 5 - 10 mm

-2,32 to -3,32

Small gravel

between 2 - 5 mm

-1 to -2,32

Coarse sand

between 1 - 2 mm

0 to -1

Medium sand

between 0,5 - 1 mm

1 to 0

Fine sand

between 0,25 - 0,5 mm

2 to 1

Finer sand

between 0,125 - 0,25 mm

3 to 2

Finest sand

between 63 µm - 0,125 mm

4 to 3

Mud

< 63 µm

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