PMT - different plate boundaries destructive continental and oceanic

Question 1

explain the process of what happens when a destructive continental and oceanic plate boundary meet each other?

Answer 1

• Denser oceanic plate subducts below
  the continental
• The plate subducting leaves a deep
  ocean trench
• Fold mountains occur when sediment
  is pushed upwards during subduction
• The oceanic crust is melted as it
  subducts into the asthenosphere
• The extra magma created causes
  pressure to build up
• Pressurised magma forces through
  weak areas in the continental plate
• Explosive, high pressure volcanoes
  erupt through the continental plate,
  known as composite volcanoes

Question 2

which plate is denser?

Answer 2

oceanic

Question 3

when do fold mountains occur?

Answer 3

sediment is pushed upwards during subduction

Question 4

what are the features of a composite volcano?

Answer 4

explosive
high pressure

Question 5

how are composite volcanos formed?

Answer 5

pressurised magma forces through weak areas in the continental plate

high pressure builds up here

explosive volcanos erupt through the continental plate