ᴘᴀʀᴛ ②-Plate Tectonics 🌋🌎 Flashcards
Mesozoic Era (middle)🐊🌸🐦🐰- 245 million years ago-66 million years ago
- age of the dinosaurs and reptiles
- first plants
- first birds
- Rocky mountain formation begins
- innuitian mountains form
- shallow sea is covered interior North America at various times
Palaeozoic Era 🐸🐍🐞🐟(ancient)-570–> 245 million yrs ago
- age of amphibians,fish,insects
- first plants and animals
- lowlands and Appalachians form
Pre-Cambrian-4.6 BILLION years ago-570 million yrs ago
- First single and multi-celled orgs evolved
- Canadian shield formed
- major volcanic activity
Seismic waves🌊
Are pulses of energy that come from earthquakes that are released, and are dangerous
What is a Tsunami 🌊🌊🌊🌊🌊🌊🌊
Giant waves from the ocean that can devastate cities at once
How are tsunamis caused?
They are caused when an earthquake shifts the ocean floor downwards
How are earthquakes caused?
When the ridges of transform boundaries grind against each other the vibrations created cause earthquakes
At what boundary does a fault occur?
Divergent boundaries
Cenozoic Era🚶🐯-66 million years ago to present (1.4%)
- human beings
- age of mammals
- modern life forms evolve
- ice sheets cover most of north america
- continents take on present shape
- rocky mountain formation complete
Reverse fault
A fault that occurs where a plate is being compressed at a convergent boundary –> ⏫
Strike slip fault
The blocks of rock that move in opposite horizontal directions…at a transform boundary
Main shocks
Earthquake with the highest magnitude
Foreshock/Aftershock
The release of kinetic energy at one fault that increase the potential energy of a nearby fault –> more earthquakes!!
How far do primary waves travel per second
They travel 1-5 miles they can pass through all three states easily
Secondary waves
Slower than primary waves, they move thru solids
