Oceanography Ch. 4
The sediment that covers the greatest area of seabed is __________. (a) terrigenous sediment (b) biogenous sediment (c) hydrogenous or authigenic sediment (d) cosmogenous sediment (e) all of these
b
Tektites are a type of __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) terrigenous sediment
b
The Wentworth scale is used to arrange the amount of sorting in a sediment deposit. (a) True (b) False
b
The calcium sulfate and other substances found in the Mediterranean by Hsü and Ryan are classified as __________. (a) oozes (b) evaporites (c) clays (d) terrigenous sediments (e) poorly sorted sediments
b
The deepest sediment samples are obtained by __________. (a) grab samplers (b) piston corers (c) gravity corers (d) platform drilling
b
The deposition of radiolarian oozes is affected by the carbonate compensation depth. (a) True (b) False
b
The oldest sediments are comparatively young because __________. (a) the rocks of the underlying ocean floor react chemically with the lowest sediments, converting them directly into rock (b) the ocean floor is recycled through plate tectonics, dragging the oldest sediments into the mantle at subduction zones (c) sediments have been falling to the ocean floor only comparatively recently (d) the physical and biological processes that make sediments have been active only a comparatively short time (e) sediments are consumed by bottom-dwelling marine organisms
b
Which of the following contains calcium carbonate (CaCO3)? (a) diatoms (b) foraminiferans (c) glauconite (d) phosphorites (e) radiolarians
b
Which of the following metals is not usually found in manganese nodules? (a) iron (b) uranium (c) nickel (d) cobalt (e) copper
b
A pelagic clay contains lots of material that settle to the seafloor through the water column and are _________. (a) less than 30% biogenous material (b) more than 30% biogenous material (c) more than 30% hydrogenous material (d) less than 30% neritic material (e) more than 30% neritic material
a
Beach sand is usually well-sorted. (a) True (b) False
a
Calcareous shells will not accumulate on the ocean floor when the water depth exceeds about 4500 meters (around 15,000 feet). (a) True (b) False
a
Coccolithophores, a type of phytoplankton, produce __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) terrigenous sediment
a
Diatomaceous ooze is a type of __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) terrigenous sediment
a
Fine and coarse sediments derived from the hard parts of organisms are termed __________. (a) Biogenous (b) Cosmogenous (c) Hydrogenous (d) Volcanogenic (e) Terrigenous
a
Geologists classify sediment either by grain size or by source. (a) True (b) False
a
Organisms that live on the ocean floor may be responsible for keeping manganese nodules from being buried in the sediment. (a) True (b) False
a
Paleoceanography is __________. (a) the study of the ocean's past (b) analysis of sediment age by tektite content (c) the study of ocean color (d) analysis of the color of sediments (e) none of the above
a
Phosphate nodules are found on the continental shelf. (a) True (b) False
a
Radiolarian oozes form near the equator. (a) True (b) False
a
Sediment may be an accumulation of the remains or products of organisms. (a) True (b) False
a
Sediments that arrive in the ocean from continents via rivers are called __________. (a) lithogenous sediments (b) biogenous sediments (c) hydrogenous or authigenic sediments (d) cosmogenous sediments (e) all of these
a
Sediments with an extraterrestrial origin are called __________. (a) cosmogenous (b) biogenous (c) hydrogenous (d) lithogenous or terrigenous (e) volcagenic
a
Some ocean sediments have come from outer space. (a) True (b) False
a
Stromatolites are a type of __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) terrigenous sediment
a
Texture refers to the size and shape of sediment particles. (a) True (b) False
a
The element found in some sediments which suggest that a meteorite or asteroid impact occurred nearby is _________. (a) iridium (b) manganese (c) strontium (d) uranium (e) yttrium
a
The most abundant sediment in the ocean is __________. (a) lithogenous sediment (b) biogenous sediment (c) hydrogenous or authigenic sediment (d) cosmogenous sediment (e) all of these
a
The most likely place to find abundant manganese nodules is on the _________. (a) abyssal plain far from a continent (b) continental rise (c) continental shelf (d) crest of a mid-ocean ridge (e) All of the above locations are contain manganese nodules
a
The oldest ocean floor sediments are about __________. (a) 160 million years old (b) 60 million years old (c) 1 billion years old (d) 6,000 years old (e) 600 million years old
a
Underlying the unconsolidated sediments of the seafloor are __________. (a) Basalt pillows and basement rocks (b) Granite boulders (c) Glacial deposits left from the Ice Age (d) Ancient remnants of sunken continents
a
Which of the following is not an important control on oceanic sediment accumulation? (a) degree of preservation (b) dilution (c) input from other sediments (d) rate of deposition (e) all of the above factors are important
a
A glacial deposit is well-sorted. (a) True (b) False
b
A well-sorted sand deposit with rounded particles might be called immature. (a) True (b) False
b
All of the following are lithogenous sediments except __________. (a) beach sand (b) diatom ooze (c) glacial deposits (d) illite clays (e) volcanogenic particles
b
Calcium carbonate is most likely to dissolve in water with which characteristics? (a) low carbon dioxide and warm temperatures (b) lots of carbon dioxide and cold temperatures (c) lots of carbon dioxide and warm temperatures (d) low pressure and warm temperatures (e) low pressure and cold temperatures
b
Dredge samplers are used to collect samples of __________. (a) specific sediment types (b) rock or sediment in bulk quantities (c) bottom dwelling organisms (d) suspended sediments (e) buried sediments
b
In the process of lithification, sediments __________. (a) are subducted into the mantle at a deep trench (b) are converted into solid rock (c) slip into the center of the mid-ocean ridges and become new seafloor (d) are uplifted to form the edges of continents (e) are uplifted to form high mountains like Mt. Everest
b
Oozes are also called __________. (a) terrigenous sediments (b) biogenous sediments (c) hydrogenous or authigenic sediments (d) cosmogenous sediments (e) all of these
b
Sediments derived from weathered rock and volcanic activity are called biogenous sediments. (a) True (b) False
b
Sediments that are organic in origin, meaning made by organisms, are called __________. (a) terrigenous sediments (b) biogenous sediments (c) hydrogenous or authigenic sediments (d) cosmogenous sediments (e) all of these
b
A very important way to increase the settling rate of fine particles in the open ocean is via _________. (a) carbonate dissolution (b) deposit feeders (c) fecal pellets (d) precipitation (e) wind
c
Carbonate sediments are rare in deep sea sediments because __________. (a) The organisms providing shells do not live in the deep sea (b) The abundance of muds and clays cover the carbonate shells (c) The carbonate shells dissolve in deep water (d) The organisms do not live beyond the edge of the continental shelf
c
Halite is a type of __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) lithogenous or terrigenous sediment
c
High energy environments are most likely to contain which one of the following? (a) clay-sized particles (b) cosmogenous sediments (c) large particles such as gravel (d) manganese nodules (e) silt-sized particle
c
Hydrogenous sediments are largely __________ precipitates that form in place. (a) extraterrestrial (b) inorganic (c) biochemical (d) volcanic
c
In general, polar neritic sediment has more _________. (a) clay than in temperate waters (b) coral debris than in tropical waters (c) rock and gravel than in tropical waters (d) shell fragments than in temperate waters (e) silt and sand than in tropical waters
c
Manganese nodules are a type of __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) lithogenous or terrigenous sediment
c
Manganese nodules are an example of a _________. (a) biogenous sediments (b) cosmogenous sediments (c) hydrogenous sediments (d) terrigenous sediments (e) volcagenic sediments
c
Metal sulfides are a type of __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) lithogenous or terrigenous sediment
c
Most of the floor of the North Pacific Ocean is covered with __________. (a) foraminiferan ooze (b) windblown dust and sand (c) red and brown clays (d) diatom ooze
c
Sediment particles precipitated near the sea floor by chemical or biochemical reactions are termed __________ sediments. (a) Biogenous (b) Cosmogenous (c) Hydrogenous (d) Volcanogenic (e) Terrigenous
c
Sediments found on continental margins are called _________. (a) continental (b) estuarine. (c) neritic (d) oceanic (e) pelagic
c
Sediments produced as a result of chemical reactions in seawater are called __________. (a) cosmogenous (b) biogenous (c) hydrogenous (d) lithogenous or terrigenous (e) volcagenic
c
Sediments that are generated in place or on the spot where find them are called __________. (a) terrigenous sediments (b) biogenous sediments (c) hydrogenous or authigenic sediments (d) cosmogenous sediments (e) all of these
c
Sediments which are poorly sorted and made of a variety of minerals could have been deposited by __________. (a) a glacier (b) a river delta (c) turbidity currents (d) a volcanic eruption (e) the wind
c
Select the finest particles in this list __________. (a) sand (b) silt (c) clay (d) granules
c
The processes which break rock and minerals into smaller particles are collectively termed __________. (a) metamorphism (b) igneous activity (c) weathering (d) erosion (e) fractionalization
c
This sediment type has particles that are sometimes made of glass. (a) terrigenous sediment (b) biogenous sediment (c) hydrogenous or authigenic sediment (d) cosmogenous sediment (e) all of these
c
Very small particles sometimes fall surprisingly quickly from near the ocean surface to the seabed, thus avoiding being carried great lateral distances by currents. This is possible because __________. (a) the particles, though tiny, are very heavy and fall quickly (b) the particles adhere to large particles and fall with them (c) the particles are compressed in the fecal pellets of small marine animals (d) the particles resist the action of currents and fall straight to the bottom
c
Abyssal clay is a type of __________. (a) biogenous sediment (b) cosmogenous sediment (c) hydrogenous sediment (d) lithogenous sediment
d
Floating and drifting single-celled plants can be referred to as __________. (a) Foraminiferans (b) Radiolarians (c) Zooplankton (d) Phytoplankton (e) Pteropods
d
In contrast to manganese nodules which form on the abyssal plain, phosphate-rich nodules form in _________. (a) continental shelf waters (b) estuaries (c) hydrothermal vent areas (d) intermediate to shallow depth water (e) mid-ocean ridge
d
Large volumes of bottom sediments may be transported long distances by __________. (a) storm waves (b) icebergs (c) tidal action (d) turbidity currents
d
Sediments derived from preexisting rocks are called __________. (a) cosmogenous (b) biogenous (c) hydrogenous (d) lithogenous (e) volcagenic
d
Sediments that are extraterrestrial in origin are called __________. (a) terrigenous sediments (b) biogenous sediments (c) hydrogenous or authigenic sediments (d) cosmogenous sediments (e) all of these
d
The oozes on the seafloor mostly consist of __________. (a) boulders and cobbles from glaciers oozing off the land (b) bones and teeth of bottom-dwelling fishes (c) fine muds washed down the continental slope to the seafloor (d) microscopic hard parts of single-celled surface living organisms (e) treated sewage from urban areas
d
All of the following are hydrogenous sediments except _________. (a) evaporites (b) halites (c) manganese nodule (d) phosphates (e) stromatolites
e
Carbonate sediments composed of the shells of marine organisms are found __________. (a) widely on all continental shelves (b) on shelf areas that were exposed to the atmosphere during periods of glaciation (c) only in the tropical Pacific (d) only on land areas once covered with ocean water (e) on some continental shelves in tropical and sub-tropical regions
e
Fine and coarse grains of sediment produced by weathering on land are termed __________ sediment. (a) Biogenous (b) Cosmogenous (c) Hydrogenous (d) Volcanogenic (e) Lithogenous
e
In volume and quantity, most marine sediments are associated with __________. (a) the edges of the deep trenches (b) the deep sea floor away from the continental slopes (c) seamounts (d) mid-ocean ridges (e) the continental slopes and rises
e
Scientists can derive information about __________ from observing deep ocean cores: (a) basin age (b) mineral resources (c) water temperature in years past (d) the history of life in the upper layers of water (e) all of the above
e
The major force bringing continental sediments to the open ocean is (are) (a) glaciers (b) neritic currents (c) rivers (d) turbidity currents (e) wind
e
This sediment type can be used to learn about the age and history of the seafloor. (a) terrigenous sediments (b) biogenous sediments (c) hydrogenous or authigenic sediments (d) cosmogenous sediments (e) all of these
e
Which of the following contains silica (SiO2)? (a) coccolithophores (b) corals (c) foraminiferans (d) phosphorites (e) radiolarians
e