Earth Science, Tarbuck Chap 13 Flashcards
Which hemisphere has more water
Southern Hemisphere
What are the four ocean basins the World Ocean is divided into
Pacific Ocean, Atlantic Ocean, Indian Ocean, Arctic Ocean
What are the 2 types of continental margins
Passive and Active
What are passive continental margins
geologically inactive
regions located a great distance from the closest plate
boundary. As a result, they are not associated with strong
earthquakes or volcanic activity.
Most of Sediment delivered to the seafloor are delivered how
Turbidity Currents and gravity settling
What are turbidity currents
downslope movements of dense, sediment-laden water.
What are turbidites
Sediment deposits caused by turbidity currents, where coarse sediments settle first and fine sediments settle last. These deposits experience graded bedding
What is graded bedding
Bedding where you can see a change between sediment size
What is the deepest known part of the world ocean
Challenger Deep in the Mariana Trench
What are guyots
Submerged Flat-topped seamounts that have been moved away from their magma source(like a hotspot or a mid-ocean ridge) by plate tectonics
What are the 3 broad categories of seafloor sediment
Terrigenous, Biogenous, Hydrogeneous
What are Terrigenous seafloor sediment
consists primarily of mineral grains that were weathered from continental rocks and transported to the ocean
Where do large Terrigenous sediment deposit
near the shore
Where do small Terrigenous sediment deposit
Small terrigenous sediment deposit very slowly, meaning ocean currents typically move them far away before they are deposit
What are Biogenous seafloor sediment
Sediment composed mostly of microscopic shells and skeletons of marine animals and algae
What is Calcareous Ooze
Most common type of biogenous deposit produced from the shells of organisms that inhabit warm surface waters.
What is Calcareous Ooze made up of
CaCO3
deeper cold seawater is richer in ______________
Carbon Dioxide
What restricts Calcareous Ooze from forming
calcareous hard parts slowly
sink through a cool layer of water; when they reach a certain depth, they begin to dissolve due to higher levels of Carbon Dioxide in deep cold seawater
At what depth do Calcareous shells fully dissolve before reaching the seafloor
depths of 4500 meters(15,000 feet)
What are Hydrogenous Seafloor Sediment
minerals that crystallize directly from seawater
through various chemical reactions.
