Darwin's subsidence theory is related to

• Marine terraces

• Coral reefs 

• Cycle of erosion

• Tides

Which one of the following sediments deposits cover the largest of the ocean floor ?

• Terrigenous

• Cosmogenous

• Biogenous

• Hydrogenous

73.

The ships on the North Atlantic sea route are forced to the South of the true great circle route by :

(1) Fogs associated with the contact of the cold Labrador current and the warm Gulf stream current.

(2) Icebergs brought southward by the Labrador current at certain seasons of the year.

(3) The strong polar icy winds from the North.

(4) The projecting landmass of Northeastern North America and the presence of warm Gulf Stream current.

• (1) and (2) are correct 

• (1) , (2) and (3) are correct

• (1) and (3) are correct

• All are correct

The most common salt in the ocean is

• Calcium chloride

• Sodium nitrate

• Sodium chloride

• Calcium nitrate

Pelagic deposits consists of matter derived from algae and are mostly in the form of liquid mud known as

• Blue mud

• Ooze

• Red mud

• Coral Mud

The average temperature of the surface water of the oceans is

• 22°C

• 15°C

• 26.7°C

• 18.6°C

The highest salinity is found in the 

• Baltic Sea

• Okhotsk Sea

• Mediterranean Sea

• Red Sea

Organic deposits made by living or dead organisms that form rock elevation like a ridge are known as

• Corals 

• Canyons

• Reefs

• Guyots

The mechanism by which energy of solar origin is transported  around the earth is

• Ocean tides

• Winds

• Ocean waves

• Tornado

The cold current flowing along the coast of Chile and Peru is known as

• Agulhas

• El-Nino

• Humboldt

• Canary