Oceanic Geological Features Flashcards
A guyot is:
An isolated underwater volcanic mountain with a flat top.
Where would you be most likely to find oil
and natural gas reserves?
Passive Margins
What is the approximate age of the oldest oceanic crust?
180 million years
New seafloor is created at:
Mid-ocean ridge or Mid-oceanic ridge
What is a distinguishing characteristic of the
seamounts of the Pacific Plate?
Conical Tops
Lying generally between the foot of a continental rise and a mid-ocean ridge,_______ are the most level parts of the deep ocean floor, usually found at depths between 3000 and 6000 m.
Abyssal Plains
What is the term for deep clefts descending from the
continental slope?
Submarine canyons
Ocean trenches are formed at ______ boundaries.
Oceanic-Oceanic Convergent
and
Oceanic-Continental Convergent
_____ _____, a coastal landform and a type of
dune system, are exceptionally flat or lumpy areas
of sand, that are parallel to the mainland coast.
Barrier Islands
A gently sloping, shallow area of the ocean floor that extends outward from the edge of a continent is called a:
continental shelf
The drving force that causes crustal plates
to move is created by:
Convection cells within the mantle
What is a tombolo composed of?
Sand
Where are you most likely to find a fresh water lens?
Beneath a sandy oceanic island
What is the most abundant extrusive rock?
Basalt
Abyssal plains are usually found at depths between 3000 and ____ meters.
6000
The black sand beaches of Hawaii are
made of what type of rock?
Basalt
Guyots are also known as _______.
Seamounts
A _____ _____ is an underwater mountain range, formed by plate tectonics.
Mid-ocean ridge or Mid-oceanic ridge
Mid-ocean ridges are created at ______ boundaries.
Divergent
Abyssal plains cover more than __% of the Earth’s surface.
50
The steep, seaward edge of the continental shelf is called the:
Continental slope
A _____ _____ is the transition between oceanic and
continental lithosphere which is not an active
plate margin. It is constructed by sedimentation
above an ancient rift.
Passive margin
An atoll is best defined as:
A ring-shaped reef, island, or chain
of islands formed of coral.
Some ______ _______ are found as extensions to large rivers; however most of them have no such association.
Submarine Canyons
The Puerto Rico Trench is the deepest part of the
Atlantic Ocean. How does this trench differ from the
deep trenches in the Pacific Ocean?
It is located at a transform plate boundary
What is a tombolo?
A bar of sand joining an island to the mainland.
A _______ ________ is a steep-sided valley cut
into the sea floor of the continental slope, sometimes
extending well onto the continental shelf.
Submarine canyon
What is the Charles Darwin theory of atoll formation?
- Formation of a fringing reef (on the side of a newly formed volcanic island)
- Formation of a barrier reef (as the volcanic island sank)
- Formation of an atoll
