14. Marine Sedimentspages 113-136 in your text

It’s a Wet, Dirty World!

Ya Gotta Love It!!!

What is Sediment?

Matter that has been deposited by some natural process

Where does marine sediment come from?

Major Sediment Input to the Oceans-Land

Rivers contribute the mostOther Sources:

Glaciers and ice sheetsWind blown dustCoastal erosionVolcanic debrisGroundwater

How do we know? We sample!

How is marine sediment classified?

•Oceanic (AKA Pelagic) – those found in the open ocean (further away from land)

•Neritic – those found in waters above continental margins (closer to land) (coastal, “n” for nearshore)

What sediments are found where?

Neritic

Pelagic

What are the sediment types?

1) Terrigenous - derived from land2) Biogenous - derived from plants and animals3) Hydrogenous - formed on or in the

sediments on the sea floor (AKA Authigenic)4) Cosmogenous - particles from outer space

See page 119 in your text for a summary of these

1) Terrigenous Sedimentex. Sahara Dust –

Turbidites – another example of Terrigenous Sediment

Like a landslide, but it happens

under water

2)

If the ocean becomes more acidic, organisms with calcium skeletons will be

in trouble

Coccolithophore subjected to acidic seas – before and after:

Corals have calcium shells – imagine a

huge worldwide reef

die-off!

Can you find the coccolithophore bloom?

Still don’t believe a teeny organism can make sediment?

Famous White Chalk cliffs in Etretat France –

actually hundreds of millions of

coccolithophores!

Famous Painting by Monet:

3 & 4)

Evaporites – an example of (3) Hydrogenous Sediment

Form when seawater

evaporates and is not replaced with fresh

water

Sampling for an example of Hydrogenous Sediment –

Hydrothermal Vents

Closer to Home…

Long Island – Fire Island Beach Sand is mostly Quartz, Garnet, and Magnetite

Grain SizesWhat is the name of this equipment?

Need To Check Your Notes?• Check your details in your text and on

these sites:http://www.indiana.edu/~g131/seds.html

http://geology.uprm.edu/Morelock/dpseaterrig.htm