Plate Features Flashcards
Identity and explain the formation of: •island arcs •young fold mountains •deep sea trenches •rift valleys •ocean ridges
1
Q
What is an island arc
A
On a subduction boundary a subducted plate is melted and this hot magma rises upwards (as it is not dense) and rises through the rock causing a volcano underwater. This underwater volcano will erupt over and over again causing rock too form an island in the surface of the water. An example of this is Japan.
2
Q
What are young file mountains
A
[plate→]~lake~[←plate]
[plate→]{sediment}[←plate]
This formation has the plate going towards each other. Over many thousands of years they push together causing the lake and some of the plate either side upwards. Eventually what will be left is a non slaty lake at the top of mountains of rock and a layer of sediment.
