folding and faulting Flashcards
orogeny
refers to mountain-building processes. This occurs due to tectonic movements that cause the plates to buckle upwards, forming fold mountains.
Geomorphology
is the scientific study of landforms and the processes that shape them. It is studied by geologists.
Denudation
is the wearing away of the Earth’s surface by moving water, ice, wind and waves.
how does folding occur?
When two continental plates collide, land is forced upwards through the process of compression.
where does folding normally take place
in sedimentary rocks as they are easier to deform.
with what are fold mouintains created?
with anticlines,
synclines and limbs
what are the four types of fold
Simple fold
Asymmetrical fold
Overfold
Overthrust fold
Simple fold
both limbs are the same.
Asymmetrical fold
pressure is applied more to one side than the other.
Overfold
pressure is so much greater that one limb has been pushed over the limb.
Overthrust fold
the pressure here is at its greatest. the rocks have been pushed so far that they have cracked. The upper limb has been pushed forward along the crack or fault line.
when was the celadonian orogeny
400 mya
give an example of celadonian orogeny
Highlands of Scotland, Appalachian Mountains, North America, Bluestack Mountains and Wicklow Mountains
what plates colided in the celadonian orogeny
the American and Eurasian plates collided
what type of trend does the celadonian orogeny have
a SW–NE trend
where is the celadonian orogeny mainly located
located in the north-western and Leinster regions of Ireland.
how high where the celadonian mouintain ranges
These mountain ranges were as high as the Alps or Himalayas today but they are much, much older.
why did the celadonian mouintains reduce in height
They have reduced dramatically in height due to the effects of weathering and erosion [denudation].
what type of rocks did the celadonian mouintains reveal
exposed some of the igneous and metamorphic rocks that lie well below the surface.
when was the amorican orogeny
250 MYA
give an example of amorican orogeny
ridge and valley landscape of Munster (Case Study), Paris Basin and France
what plates colided in the amorican orogeny
African and Eurasian plates collided.
what trend does the amorican orogeny have
The folding has an E–W trend.
when did redstone develop in ireland
when Ireland had desert climate approx. 380mya
what formed on top of the layers of ORS 350mya, when Ireland lay below a warm, shallow sea.
Limestone
what are munster ridge and valley
Armorican fold mountains
why did the munster ridge and valley happen
The African and Eurasian continental plates collided, causing land to buckle upwards.
where did the munster ridge and valley happen
Munster, Ireland
when did the munster ridge and valley happen
250 mya
what caused the munster ridge and valley (not the plates)
compression caused by two plates colliding caused these rock strata to fold into anticlines and synclines.
example of munster ridge and valley mouintains
e Galtees, Comeraghs and Macgillycuddy Reeks.
what effect did the munster ridge and valley have
Trellised drainage patterns as the rivers along the valleys try to navigate their way southwards to the sea. E.g. Bandon , Lee and Blackwater.
