1. Marine Sediments and Sedimentation

2. What is Sediment?
Sediment is any loose material which can be transported by a liquid that eventually settles at the bottom of the liquid
Consists of organic and inorganic matter from a number of biological and geological activities:
Erosion of rock
Volcanic eruptions
Activity of living organisms
Marine sediment has a variety of size, shapes, and colors

3. Characteristics of Marine Sediment
Marine sediment color ranges from red and dark brown to creamy white
Organic sediment (white)
Iron oxide (red, brown)
Clay deposits (blue, green)
Particle size ranges from mm
Marine sediment characteristics vary geographically
Thickness of sediment layer
Source of sediment

6. Sediment Size
Sediment is classified by particle size ranging from large boulders to fine clay
Most marine sediment is found at the smaller end of the spectrum as sand, silt, and clay
The smaller the sediment size, the easier it is for it to be carried by streams, waves, and currents

8. Sediment Source Marine sediment can be classified by origin
Marine sediment can be classified into four categories:
Terrigenous
Biogenous
Hydrogenous
Cosmogenous

9. Terrigenous sediment Derived from land
Terrigenous sediments are the most abundant sediment
Formation is a part of cycle that moves through different parts of the Earth
Erosion of land masses runs off into oceans and accumulates on the ocean floor
Clay is one type of terrigenous sediment
38% of ocean floor is covered in clay

10. Biogenous Sediment Derived from the remains of marine organisms
Plankton, coral, mollusks (high levels of CaCO3)
After organisms die, the hard structures fall to the bottom of the ocean
Over millions of years, fossil fuels are formed
Ooze is a type of biogenous sediment that contains 30% organic material
Primarily composed of dead microorganisms

11. Prominent examples are manganese and phosphorous nodules
Hydrogenous Sediment
Cosmogenous Sediment
Hydrogenous sediment is formed from minerals that have precipitated from dissolved minerals
Originate from submerged rock, hydrothermal vents, and river runoffs
Prominent examples are manganese and phosphorous nodules
Cosmogenous sediment originate from the cosmos or outer space
Dust from asteroids and comets can build up on ocean floor
Microtektites – small particles formed from the impact of an asteroid