D) strontium. D) strontium.
A) oceanic ridges
B) hot water
C) mineral-rich waters
D) all of these
A) are sites for submarine eruptions of basaltic lava A) are sites for submarine eruptions of basaltic lava
B) are where young lithosphere is added to the edges of spreading, oceanic plates
C) terrigenous sediment coverings are very thin or absent
D) sediments include thick siliceous ooze deposits and sandy turbidite beds
A) abyssal plain far from a continent.
B) continental rise.
C) crest of a mid-ocean ridge.
D) continental shelf.
E) All of the above locations contain manganese nodules.
A) hydrogenous sediment
B) biogenous sediment
C) terrigenous sediment
D) both terrigenous and biogenous sediment
A) more than 30% biogenous material.
B) more than 30% hydrogenous material
C) more than 30% neritic material
D) less than 30% biogenous material.
E) less than 30% neritic material.
A) lie at depths exceeding 6 kilometers
B) are geologically old features
C) are heavily mantled with sediment
D) contain active rift zones
A) rift zones
B) mountainous topography
C) volcanic structures
D) all of these
A) degree of preservation
B) rate of deposition
C) input from other sediment types
E) All of the above factors are important.
A) the Southern Hemisphere has much more water surface than the Northern Hemisphere
B) the Northern Hemisphere has much more water surface than the Southern Hemisphere
C) the percentage of land and water is about the same in both the Northern and Southern Hemispheres
D) none of the above are true
A) sodium chloride
B) sodium bicarbonate
C) potassium bromide
D) magnesium chloride
A) by rivers during the ice age
B) because of a plate plunging into the mantle
C) by faulting
D) none of these
A) a rapid steepening of the gradient occurs
B) the water depth reaches 100 fathoms
C) it meets an oceanic ridge
D) the gradient becomes very gentle