GEOGRAPHY TEST 1 Flashcards
WHAT IS FOLDING?
Folding is the process in which rocks are bent and crumpled due to compressional forces arising from the convergence of 2 plates. It results in the formation of fold mountains.
WHAT IS FAULTING?
Faulting is the process in which rock masses move along fractures in the Earth’s crust. These fractures are called faults.
HOW DOES FOLDING OCCUR?
Folding occurs due to compressional forces in the rock, this causes the rock to bend forming folds.
HOW DOES FAULTING OCCUR?
Faulting occurs due to tensional forces or compressional. It creates stresses and strains in the rock causing fractures called faults.
WHAT IS AN ANTICLINE?
Upward folds like arches are called anticlines. In an anticline, a fold arches away from the earth. The top of the arch is called the crest of the anticline.
WHAT IS A SYNCLINE?
Synclines are downward folds like troughs. In a syncline, the fold bends down towards the earth.
WHAT IS AN ASYMMETRICAL FOLD?
This is where one limb of the fold dips more steeply than the other.
WHAT IS AN OVER FOLD?
This is a fold in which one or both limbs have been inclined more than 90 degrees from their original orientation.
WHAT IS A NORMAL FAULT?
A tensional or normal fault results from 2 forces moving in a horizontal plane in opposite directions. The rocks are under tension and finally break causing the rocks to become jointed with normal faults. The tension in the rocks are normally caused by tectonic plates moving apart.
WHAT IS A REVERSE FAULT?
A compressional or reverse fault is caused by compression of the rock at a convergent plate zone. This can cause bending and folding of the rock layers and may result in the faulting of the rock. Forces move towards each other causing compression and reverse faulting.
WHAT IS A TEAR OR TRANSFORM FAULT?
A tear/ transform/ strike fault occurs when two plates slide pass each other, along a transform boundary. The plates slide pass each other with no vertical movement.
WHAT IS FOLD MOUNTAINS?
When 2 convergent plates in crust, a continental and oceanic plate collide, the oceanic plate is forced beneath the continental plate. The rocks are squeezed by the convergent plate movements and the rocks of the continental plate margins that lie above the subduction zone are pushed upwards and buckle and crumple into folds that forms fold mountains. The collision between the South American continental plate and the oceanic Nazca plate has resulted in the formation of the Andean chain of fold mountains. Fold mountains are also formed when two continental plates collide. The Alps was formed by the collision of the Eurasian plate and the African plate. There was no subduction zone, one plate was being pushed beneath the other, resulting in the formation of fold mountains.
WHAT IS WEATHERING?
Weathering is the breakdown but not the removal of rocks.
