MOUNTAIN RANGES AND CONTINENTAL PROCESSES
MOUNTAIN RANGESAND CONTINENTAL PROCESSESHow are mountains
formed?Several factors that contribute to the formation of mountain
structures: Rock WeatheringErosionMetamorphismCompressional
ForcesFaultingVolcanic ActivityOrogenesisFrom the Greek oro,
meaning mountain and genesis, meaning to come to being
The process of mountain building.Two questions regarding
orogensisWhat is the origin and mechanism of the forces that cause
crustal deformation.
What is the forces that prevent the mountain system from erosion
or weathering.AnswerCRUSTAL UPLIFT
Sir George everestConducted Topographic Survey in India
Used two methods of Measurement: 1. Conventional use of
Triangulation, 2. Astronomical Measurement
Plumb Bob a simple device composed of a metal weight suspended
on a string and is used to assess vertical orientation.Mountain
buildingSubduction zoneAnother possible site of mountain
building.Similar to continental collision zone wherein a dense
plate dives down a less dense plate.Areas where volcanic arcs
form.Islands (volcanic arcs)As the oceanic plate subducts under
another plate, partial melting at the oceanic plate occurs and some
mantle material rises up to form the beginnings of an underwater
volcano.
Volcanic arc systems are recognize as an integral step in the
process of mountain building. Mountain building along subduction
zones with continental marginsIn the same manner as subduction
zones concerning purely oceanic plates, oceanic-continental plate
type subduction zone can promote mountain building. A prime example
of this is the Andes Mountain Range forming the backbone of the
south American continent. Accretionary wedgeIs composed of
sedimentary and metamorphic rocks mixed in with oceanic
crust.Continental collisionThere is another form of collisional
mechanism that can lead to the formation of mountain belts.
Remember that the cause of a subduction mechanism is that one of
the colliding plates is denser (the oceanic plate) and thus will go
under the lighter plate (continental plate).
