Convection Currents
What drives convection currents in the mantle?
Heat from Earth’s core.
Name the three main rock types.
Igneous, sedimentary, metamorphic.
Define weathering.
Breaking down rocks into smaller pieces.
What does large, angular grains indicate?
Bonus - Where in the river system is this found most?
High-energy environment.
At the top of the river system.
What is the hardest mineral on the Mohs scale?
Diamond.
What do convection currents move?
Tectonic plates.
Which rock forms from cooled magma?
Igneous.
Define erosion.
Movement of rock particles by wind, water, or ice.
What does well-sorted fine sediment indicate?
Low-energy environment.
What is the softest mineral on the Mohs scale?
Talc.
Where do convection currents occur?
In the mantle.
Which process forms sedimentary rocks?
Compaction and cementation.
Give one example of physical weathering caused by water.
Water seeping into cracks and breaking rocks apart through repeated wetting and drying (or river abrasion).
Why are grains rounded in lower valleys?
Abrasion during transport.
If a mineral can be scratched by a fingernail, what is its hardness?
About 2.5.
How do convection currents cause earthquakes?
They move plates that stick and release stress.
What forms metamorphic rocks?
Heat and pressure.
Give one example of chemical weathering.
Acid rain dissolving limestone.
Which environment shows very low energy?
Ponds or dams.
What is the hardness of quartz?
7.
Explain how convection currents relate to plate tectonics.
They drive plate movement and cause geological activity.
Give one example of each rock type.
Granite (igneous), sandstone (sedimentary), marble (metamorphic).
Explain the difference between weathering and erosion.
Weathering = breakdown; erosion = transport.
Explain how sorting relates to transport distance.
Bonus - How does particle size relate to transport distance?
Longer transport = better sorting
Longer distance - finer the grains
Explain how Mohs scale helps identify minerals.
By comparing scratch resistance.