Oceanography Chapter 5: MC
Calcareous ooze is formed from shells of ____.
- Foraminifera - Coccolithopres
Biogenous sediments are most abundant ____.
- Near continental margins - Areas of upwelling
Which one of the following forms siliceous ooze? a. foraminifera b. radiolarians c. coccolithophores d. diatoms e. a&c f. b & d
- Radiolarians - Diatoms
The sediment layer lying on the base of the Sohm Abyssal Plain near Nova Scotia is notably thick for an ocean floor. Approximately how thick is this layer?
1,800 meters
Manganese nodules are the result of extremely slow rate chemical reactions that take place on the deep ocean floor. An average rate of growth for these nodules is roughly ____ millimeters per year.
5x10^-6
The ocean and some continental land masses are over 4 billion years old. How old are the oldest marine sediments?
About 180 million years old
Calcareous and siliceous oozes are ___.
Biogenous
Which sediment type covers the greatest area of deep-ocean bottom, such as on the abyssal plain?
Biogenous
What has the greatest average sediment thickness?
Continental Slope
What has the least average sediment thickness?
Deep-ocean floor
At depths below the carbonate compensation depth, calcareous oozes ____.
Fail to accumulate due to increased acidity and decreased temperature.
Evaporites are ____ deposits that include salts that precipitate from water that evaporates from isolated arms of the ocean or form landlocked seas or lakes.
Hydrogenous
JOIDES is an acronym that stands for ____.
Joint Oceanographic Institutions for Deep Earth Sampling
Occasionally cosmogenous sediments includes translucent oblong particles of glass known as ____.
Microtektites
The rocks of Earth's crust are made up of ____.
Minerals
As opposed to pelagic sediments, neritic sediments are found ____.
Near the Coast
Sediments of the continental slope, continental rise, and the deep ocean floor that originate in the ocean are called ____.
Pelagic Sediments
Sediments with a mixture of sizes are known as ____.
Poorly sorted sediments
What are the two second most valuable physical marine resource?
Sand & Gravel
Shells of single-celled algae called diatoms form ____.
Siliceous ooze
Most neritic sediments are ___.
Terrigenous
What type of sediment covers the least amount of the ocean floor?
Terrigenous
What has the least abundant sedimentary deposition?
The east coast of North America
Fine particles of sediment can be classified as: sand, silt or clay. These particles are defined by ____.
Their size
A dilute mixture of sediment and water that periodically rushes down the continental slope is a ____.
Turbidity current
