Earth's Crust
This outermost layer of Earth is where we live and where most rocks and soil are found.
What is the crust?
The mantle lies directly beneath this layer. Name the layer above the mantle.
What is the crust?
The outer core is one of Earth's layers made of what state of matter
What is liquid?
What state of matter is the inner core?
Solid.
What is a mineral? (Name one characteristic that all minerals share.)
A naturally occurring, inorganic solid with a definite chemical composition and a crystalline structure
Building blocks of rocks
Is the Earth's crust generally thicker under continents or under oceans?
Under Continents
The mantle is mostly solid but can slowly flow. The slow flow of the upper mantle is due to...
What are convection currents?
The outer core is mostly which two metallic elements?
What is liquid iron and nickel?
The inner core is primarily composed of which metal?
Iron and nickel
Name two physical properties used to identify minerals in the field.
What is hardness, color, streak, luster, cleavage/fracture
Give one main composition (type of rock or material) commonly found in the crust.
What is basalt and granite?
Compared with the crust, is the mantle generally hotter or cooler?
hotter
How does the outer core create a magnetic field?
Outer core (moving liquid iron) helps generate Earth's magnetic field.
Is the inner core hotter or cooler than the outer core?
Inner core is slightly hotter than or similar in temperature to the outer core; inner core temperatures are extremely high (estimates around 5000–6000°C).
What is the basic building block of most rocks?
Minerals
State one property of the crust
least dense layer
includes the lithosphere
least thick layer
on Earth's surface
How would we describe the texture or state of matter of the mantle?
semi-solid
gooey
plasticy
Compared to the mantle, is the outer core more or less dense?
More dense than the mantle.
Compared with all other Earth layers, the inner core has the highest density. True or false?
True
Explain (one sentence) how minerals contribute to the composition of a rock.
Rocks are made of one or more minerals; the types and amounts of minerals determine the rock's composition and properties.
Approximate thickness range of continental crust in kilometers (pick the best answer): about 5–70 km, 30–50 km, or 100–200 km?
What is 5-70 km?
Approximate thickness of the mantle in kilometers (choose the best approximate value): about 10 km, 2900 km, or 6000 km?
What is 2,900 km?
Estimate the relative temperature range: is the outer core generally cooler than 1000°C, about 2000–3000°C, or over 4000°C?
Over 4000°C (the outer core is extremely hot—estimates often exceed 4000°C).
Give a brief reason (one sentence) why the inner core remains solid despite very high temperatures.
High pressure in the inner core forces atoms into a solid structure despite very high temperatures.
How could a collection of rocks be organized into sedimentary, igneous, and metamorphic rocks?
Igneous rocks are formed by the cooling of hot liquid magma, or lava. Sedimentary rocks are formed from particles that have been deposited over time in layers by ice, water, or wind. Metamorphic rocks began as other kinds of rocks but changed because of extreme pressure and heat.