rocks and keywords Flashcards
What are the 3 rock types?
- igneous
- metamorphic
- sedimentary
How is igneous rock formed?
They are formed by magma from the molten inside part of of the Earth
How is Metamorphic rock formed?
They have been subjected with tremendous heat and pressure causing them to change into a different type of rock
How is Sedimentary rock formed?
They are formed from sediments that have formed at the bottom of the lake and they have been compressed over 1,000,000 years
What does Erosion mean?
Erosion means the removal of parts of the land’s surface. It is caused by river, wind, water and ice
What does Hydraulic Action mean?
Hydraulic action means the force of the water on the rock surface can cause air to be trapped in cracks. pressure weakens rocks
What does Abrasion mean?
Abrasion means rocks and stones are thrown at the rock surface. They scrape it like sandpaper.
What does Attrition mean?
Attrition means rocks knock together and wear it away.
What does solution mean?
Solution means water dissolves the surface of rock
What does Weathering mean?
Weathering means the slow breakdown of the Earth’s surface. it is caused by rain or changes in temperature can be plants and animals
What does Biological mean?
Biological means burrowing animals burrow into cracks making it bigger and splitting the rock. Plants can grow in cracks.
What does Chemical mean?
Chemical means rainwater is slightly acidic because carbon dioxide from the air dissolves it. Minerals react with water causing it to be weathered.
What does Mechanical/Physical mean?
Mechanical/Physical means water gets into cracks of rock then freezes it that expands pushing the crack further apart. When the ice melts water gets in. Repeats . Called free thaw weathering
