Plate Movements 2023 PDF

PLATE MOVEMENTS CHAPTER 10.2 RECAP RECAP  Oceanic crust:  Denser  Thinner  Contains heavier elements (iron, magnesium etc.)  Continental crust:  Thicker  Less dense  Contain lighter elements (aluminum, silicon etc.) PLATE BOUNDARY = WHERE TWO PLATES MEET PLATE MOVEMENT TYPES...

PLATE MOVEMENTS CHAPTER 10.2 RECAP RECAP  Oceanic crust:  Denser  Thinner  Contains heavier elements (iron, magnesium etc.)  Continental crust:  Thicker  Less dense  Contain lighter elements (aluminum, silicon etc.) PLATE BOUNDARY = WHERE TWO PLATES MEET PLATE MOVEMENT TYPES OF PLATE BOUNDARIES 1. Divergent boundaries: plates that move away from each other 2. Transform boundaries: plates slide past each other 3. Converging boundaries: plates collide with each other PLATE MOVEMENT  DIVERGING BOUNDARIES  Diverging plates move away from each other  If this happens on the ocean floor, places called ocean ridges (underwater volcano chains) will form   If seafloor spreading! this happens on land, places called rift valleys form  magma rises from the asthenosphere, filling the rift and forming new crust. DIVERGENT BOUNDARIES - ICELAND Diverging boundaries are also known as constructive boundaries as new crust is formed E.g. the Mid Atlantic Ridge runs through Iceland.  Magma spews up into the rift in several active volcanoes  Iceland is growing at a rate of 2-5 cm per year!  CONVERGING BOUNDARIES Converging boundaries collide together, destroying rock. They can be known as destructive boundaries.  CONVERGING BOUNDARIES Continental- continental convergent boundary: When two continental plates collide, rocks get pushed upwards forming large mountain ranges as seen in the Himalayas  CONVERGING BOUNDARIES  Oceanic-continental convergent boundary When an oceanic and a continental plate collide, the denser oceanic crust is pushed underneath the continental crust, creating deep trenches.  This process is called subduction, and the locations are called subduction zones.  CONVERGING BOUNDARIES Oceanic-continental convergent boundary The pressure on the continental plate above creates fold mountains and active volcanoes E.g. Pacific Ring of Fire  CONVERGING BOUNDARIES  Oceanic-oceanic When two oceanic plates collide, the faster plate undergoes subduction  deep trench formed  The plate underneath melts, forming magma which rises to the surface  creates oceanic volcanos which cool to form islands arcs. CONVERGING BOUNDARIES  TRANSFORMING BOUNDARIES Transform boundaries occur when plates slowly slide past each other in parallel Pressure builds up until sudden slips cause an earthquake. Oceanic earthquakes can form tsunamis.  TRANSFORMING BOUNDARIES Fold mountains typically form along the boundary. Cracks in the plate along the boundaries are known as fault lines. E.g. San Andreas Fault in California Summary: Define each type of plate boundary and give real world examples of plate boundary locations