The Atlantic and Gulf coasts show the classic form of a passive continental margin:
a low-lying coastal plain, broad continental shelf, then a steep continental slope, gentle continental rise
What are passive continental margins?
A passive continental margin occurs
where the transition from land to sea is not associated with a plate boundary
. The east coast of the United States is a good example; the plate boundary is located along the mid Atlantic ridge, far from the coast. Passive margins are less geologically active.
What are three major features of a passive continental margin?
The features comprising passive continental margins include
the continental shelf (the flooded extension of the continent), the continental slope (has the steepest slope), and the continental rise
.
How are continental margins characterized?
The active continental margins referred as the Pacific-type margins are the zones of seismically active convergent plate boundaries. These are characterized by
subduction zones formed under variety of settings such as oceanic–oceanic, oceanic–continental
, etc.
Which of the following is a characteristic of an active continental margin?
An active continental margin is a coastal region that is characterized by
mountain-building activity including earthquakes, volcanic activity, and tectonic motion resulting from movement of tectonic plates
. Characteristics of active continental margins include: They are located mostly along convergent plate boundaries.
What are the two types of continental margins?
There are two types of continental margins:
active and passive margins
. Active margins are typically associated with lithospheric plate boundaries. These active margins can be convergent or transform margins, and are also places of high tectonic activity, including volcanoes and earthquakes.
What is an example of a passive continental margin?
Examples of passive margins are
the Atlantic and Gulf coastal regions
which represent setting where thick accumulations of sedimentary materials have buried ancient rifted continental boundaries formed by the opening of the Atlantic Ocean basin.
What is the difference between an active and passive continental margin?
An active continental margin is found on the leading edge of the continent where it is crashing into an oceanic plate. …
Passive continental margins are found along the remaining coastlines
.
How are passive continental margins formed?
A passive margin forms by
sedimentation above an ancient rift, now marked by transitional lithosphere
. Continental rifting creates new ocean basins. Eventually the continental rift forms a mid-ocean ridge and the locus of extension moves away from the continent-ocean boundary.
What is the best description of a passive margin?
Passive margins (also known as rifted margins)
mark the sites where continents have rifted apart to become separated by an ocean
. Thus, passive margins consist of a seawards tapering wedge of continental crust that is dissected by faults, overlain by sedimentary basins and juxtaposed with oceanic crust.
What do you mean by continental margin?
Continental margin, the submarine edge of the continental crust distinguished by relatively light and isostatically high-floating material in comparison with the adjacent oceanic crust. It is the name for
the collective area that encompasses the continental shelf, continental slope, and continental rise
.
What are active continental margins separated by?
Active continental margins are those that are tectonically active, such as along much of the Pacific coast. Active margins are marked by
earthquakes, volcanoes, and mountain belts
. Unlike passive margins, they lack a continental rise and abyssal plain.
What are the three types of continental shelves?
The shelf area is commonly subdivided into the
inner continental shelf, mid continental shelf, and outer continental shelf
, each with their specific geomorphology and marine biology.
What do passive and active continental margins have in common?
Volcanoes and earthquakes
are common at active margins. Active margins are near plate boundaries. Passive margins are passive. They have little or no geological activity.
Where is continental rise found?
The continental rise completely
surrounds Antarctica covering
39.4% of the Southern Ocean (see Table), forming a halo of sediment surrounding the Antarctic continent.
Where is an active continental margin?
An active continental margin refers to
the submerged edge of a continent overriding an oceanic lithosphere at a convergent plate boundary
by opposition with a passive continental margin which is the remaining scar at the edge of a continent following continental break-up.
