Hjulstrom Graph

Silt and Sand are picked up at velocities of 20cm/sec?

• True

• False

There is a negative relationship between velocity and particle size when looking at Fall Velocity

• True

• False

What happens when velocity is 10cm/sec

• Boulders are transported

• Pebbles are transported

• Gravel is transported

• Sand is transported

Which particles are entrained at 1000 cm/sec?

• Just clay

• Silt and sand only

• All types of sediment

• Only boulders

What is settling velocity of gravel

• approximately 900 cm/sec

• approximately 20 cm/sec

• Approximately 1 cm/sec

• Approximately 0.2 cm/sec

Once clay is entrained it will...

• fall to the river bed when a bear pounces on the salmon

• be deposited on the levees

• not be deposited until it reaches the sea.

• be deposited as the river slows to 0.5 cm/sec

Why is the entrainment velocity higher for particles like clay compared to silt and sand?

• Clay and silt particles are larger therefore require more energy to entrain.

• The mean settling velocity is slower than the critical erosion velocity

• Clay particles form stronger bonds than sand particles

• Sand is very sticky

What do you think Flocculation means?

• In the sea clay and silt particles begin to stick together then fall to the seafloor

• when a company goes public to sell shares on the stockmarket

• the current tense of floccing

• Feeding a flock of birds

This model is called what?

• The Hjulstrom Curve

• The Butler Model

• The Burgess Model

• The Bradshaw Model

Which is the smallest particle size classified on the Hjulstrom Curve

• Silt

• Sand

• Gravel

• Clay