Geo Oce Final Flashcards
3 Continental Margin Types?
1) Active Margin - edge of continent w/ tectonic plate
2) Passive Margin - away from tectonic plate
3)Submarine Canyon
2 Marine Geo Methods?
1) Indirect - no samples collected
2) Direct - samples collected
Define Turbidity Currents
Rapid sediment heavy flow of water that moves down slope that is caused by increase in water density (high sed. Levels)
Name the 6 Sources of Marine Sediments …remember B.A.T. and V.E.T
1) Transporterd (clastic)
—Volcanic
—Terrigenous - from land
—Extraterrestrial - from space
—Authogencic - produced on sea floor
—Biogenic - settles from surface waters down
Explain Sediments and ocean fertility
Increasing fertility = Biological Productivity & Increasing Nutrients
Name the 3 classifications of River Deltas
River Dominated - shaped by river itself
Wave Dominated - movement of waves control deltas size and shape
Tide Dominated - develop where long range between high and low tides creates strong tidal currents
Define Hjulstrom Curve and what is expresses
Displays the relationship between water velocity and grain size
- it takes more energy to erode a partial then to transport it
- it takes more energy to erode a larger particle than smaller ones
- it takes more energy to erode finer grains than coarser ones
Define rimed carbonate platforms
Has a rim around it that that is a barrier such as a reef. The barrier has a steep slope into deeper water
Define Non - rimed carbonate platforms
No rim with a gradual gentle slope
Describe the layers of Sediments and Ocean Fertility
MOR
Calcarious Ooze
CCD
Siliceous Ooze
Red Clay / Diatom
Below CCD = Low productivity
What defines a terrigenous clastic dominated shelf?
Sediments become finer seaward as energy level drops
Define continental margin and what it consists of
Transition zone between shelf and deep ocean. Consists of shelf, slope, rise, and abyssal plains
Acronym; Shelly Steams Ricr Plain
What is a longshore drift? And longshore currents?
This can significantly impact coastline. Waves move parallel to shore because of longshore currents which push water in a zigzag pattern to and from shore.
Describe waves and how they break
Wave length decreases + wave height increases until it breaks
Define Wave Reflection
Waves change direction as they collide with a barrier. Moves sediments and material creating quiet beaches.
Define Oceanic Rift Valley
Forms through divergence when tectonic plates move apart (spreading)
What is the calcium carbonate compensation depth
Depth where the Rate of input from the water column is the same as rate of dissolution from water column. Sediments lie exposed on seafloor
Types of estuaries
1) Fjord - U shapes formed by glaciers
2) Bar-Built - sandbars and barrier islands formed by waves
3) Coastal Plain - valleys are flooded - most common
4) Tectonic - major crack in land occurs creating below sea level basin
