Geophysical surveys: seismic, gravity, magnetics and electrical
Earth Layers The Earth is divided into four main layers. *Inner Core *Outer Core *Mantle *Crust
The Crust The Earth’s crust is like the skin of an apple. It is very thin compared to the other three layers. *The crust makes up 1% of the Earth. * The crust of the Earth is broken into many pieces called plates.
The Mantle The mantle is the layer below the crust. The mantle is the largest layer of the Earth. The mantle is divided into two regions: the upper and lower sections.
Outer Core The core of the Earth is like a ball of very hot metals. * The outer core is liquid. * The outer core is made up of iron and is very dense.
Inner Core * The inner core of the Earth has temperatures and pressures so great that the metals are squeezed together and are not able to move. * The inner core is a solid.
Lithosphere The lithosphere consist of the crust plus the very upper part of the mantle
Asthenosphere Layer of the mantle directly below the Lithosphere. Upper Mantle that is soft and bendable like plastic (but still solid).
Review 1) What are the four layers of the Earth? 2) The Earth’s crust is very ______? 3) The mantle is the largest layer of the Earth? True or False 4) Is the Outer Core a liquid or a solid?
Plate Tectonics If you look at a map of the world, you may notice that some of the continents could fit together like pieces of a puzzle.
Plate Tectonics The Earth’s crust is divided into 12 major plates which are moved in various directions. This plate motion causes them to collide, pull apart, or scrape against each other. The word, tectonic, refers to the deformation of the crust as a consequence of plate interaction.
Divergent Boundaries This map shows the age of the oceanic crust. The red coloring shows the youngest ages, while the dark blue shows the oldest ages (around 200 million years old). The divergent boundary runs straight through Iceland….
Divergent Boundaries Spreading ridges –As plates move apart new material is erupted to fill the gap
Convergent Boundaries There are three styles of convergent plate boundaries 1. Continent-continent collision 2. Continent-oceanic crust collision 3. Ocean-ocean collision
Continent-continent Collision make mountains Himalayas
Continent-Oceanic Crust Collision Also called subduction form volcanoes
Ocean-Ocean Plate Collision Forms deep ocean trenches Mariana Trench is 11km deep!
Transform Boundaries Where plates slide past each other San Andreas Fault
Color Code Plate Boundaries You will need this map to complete future assignments