Natural Hazards Week 2 Notes
Movement of tectonic plates create most of the major geological features of earth,
including earthquakes, volcanoes, mountain chains, mineral deposits, plays a major
role in driving climate, ocean and atmospheric circulation and evolution.
The core and mantle are the source of much of the earths heat.
Heat is released by radiation and convection. Convection of the mantle and the
asthenosphere drives the tectonic cycle. The collision of lithospheric plates causes
most of the major features and activity on the surface of the earth.
The lithosphere is not one continuous later. It is broken up into plates that move
relative to each other a few cms a year. Lithospheric plates can be created and
Lithospheric plates move horizontally. Movement of the lithospheric plates are
accommodated by subduction (destruction) where plates converge and the creation
of new lithospheric material where plates diverge.
The earth’s heat is generated by radiation and convection.
Convection is ultimately responsible for the earths tectonic cycle.
Atlantic ocean growing bigger by 5cm a year.
There are three types of convergent margins – When an oceanic plate collides with
the continental crust (creating a costal range of volcanoes and mountains), when
two oceanic plates collid