Great Oxygenation Event: How Oxygen Filled the Atmosphere
Over 4 billion years ago, Earth’s atmosphere was mostly methane & nitrogen. The Great Oxygenation Event marks a time when free oxygen filled the atmosphere.
Geology
Pangea Fossils: Evidence of the Pangaea Supercontinent
At one point in time, all continents were merged together as one supercontinent “Pangea”. We’ve used fossil evidence to know continental drift exists.
Pacific Ring of Fire: Volcanoes, Earthquakes and Plate Tectonics
The Pacific Ring of Fire has the most active chains of volcanoes in the world. This is because tectonic plates collide and sink at these zones of subduction.
Divergent Plate Tectonics: Boundaries that Pull Apart
Beneath the oceans, lava erupts every day from mid-oceanic ridges. These divergent plate boundaries pull apart from each other creating new igneous rock.
North American Plate: Tectonic Boundary Map and Movements
The North American plate extends all the way over the North pole to Siberia. It also includes Greenland, Cuba, the Bahamas and part of the Atlantic Ocean.
How Was the Grand Canyon Formed?
Like a stack of pancakes, younger rock layers pile on top of older layers. We use the law of superposition to reveal Earth’s age and Grand Canyon geology.
The Cenozoic Era: From Dinosaur Extinction to Human Evolution
The Cenozoic Era started with the extinction of dinosaurs and moved into the age of mammals.This led to the diversification and increase in size of mammals.
Was the Late Heavy Bombardment a Violent Stage in Earth’s History?
At the end of the Hadean Eon, the Earth was in the late bombardment stage. Earth and the entire solar system was pelted by asteroids, comets and objects.
How Does the Supercontinent Cycle Work?
If you went 200 million years back in time, Earth was 1 supercontinent. Now, it’s made up of 7 separate continents. This is the supercontinent cycle at work.
What Is Pangaea? Piecing Together the Supercontinent Jigsaw Puzzle
About 200 million years ago, all the continents were together as one giant supercontinent known as Pangaea. Over time, these continents have broken apart.
Mass Wasting: Weathering, Erosion and Transport
From the remarkable process of plates colliding and building mountains. They are only to be dismantled by mass wasting (weathering, erosion and transport).
What is Radioactive Decay Inside Earth?
Four radioactive isotopes inside Earth account for 50% of its internal heat. Like a slow cooker, they slowly release heat within the planet keeping it warm.
Continental Drift: A Tale of Moving Continents and Plate Tectonics
Plate tectonics are deceptively slow. It’s just centimeters each year. Continental drift is the idea that continents passively move due to tectonic activity
Mantle Convection: Earth’s Plate Tectonic Conveyor Belt
Under the rigid layer of rock we live on, the Earth is plastic & more dense. Because of its fluid properties, mantle convection can occur within the Earth.
Metamorphic Rocks: Heat, Pressure and Metamorphism
If you take an existing rock and add immense heat or pressure to it, the rock becomes soft and pliable like cookie dough transforming into metamorphic rocks.