earth science

Mantle (geology)

Mantle (geology) is a earth science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Mantle (geology) rather than just read about it. In short: A mantle is a layer inside a planetary body bounded below by a core and above by a crust. Mantles are made of rock or ices, and are generally the largest and most massive layer of the planetary body.

Key takeaways

Mantle (geology) belongs to earth science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Mantle (geology) to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Mantle (geology) from memory before moving on to harder problems.

Reference excerpt

A mantle is a layer inside a planetary body bounded below by a core and above by a crust. Mantles are made of rock or ices, and are generally the largest and most massive layer of the planetary body. Mantles are characteristic of planetary bodies that have undergone differentiation by density. All terrestrial planets (including Earth), half of the giant planets, specifically ice giants, a number of asteroids, and some planetary moons have mantles.

Examples

Earth

The Earth's mantle is a layer of silicate rock between the crust and the outer core. Its mass of 4.01 × 1024 kg is 67% of the mass of the Earth. It has a thickness of 2,900 kilometres (1,800 mi) making up about 84% of Earth's volume. It is predominantly solid, but in geological time it behaves as a viscous fluid. Partial melting of the mantle at mid-ocean ridges produces oceanic crust, and partial melting of the mantle at subduction zones produces continental crust.

Other planets Mercury has a silicate mantle approximately 490 kilometers (300 miles) thick, constituting only 28% of its mass. Venus's silicate mantle is approximately 2,800 kilometers (1,700 miles) thick, constituting around 70% of its mass. Mars's silicate mantle is approximately 1,600 kilometers (990 miles) thick, constituting ~74–88% of its mass, and may be represented by chassignite meteorites. Uranus and Neptune's ice mantles are approximately 30,000 km thick, composing 80% of both masses.

Moons Jupiter's moons Io, Europa, and Ganymede have silicate mantles; Io's ~1,100 kilometers (680 miles) silicate mantle is overlain by a volcanic crust, Ganymede's ~1,315 kilometers (817 miles) thick silicate mantle is overlain by ~835 kilometers (519 miles) of ice, and Europa's ~1,165 kilometers (724 miles) km silicate mantle is overlain by ~85 kilometers (53 miles) of ice and possibly liquid water. The silicate mantle of the Earth's moon is approximately 1300–1400 km thick, and is the source of mare basalts. The lunar mantle might be exposed in the South Pole-Aitken basin or the Crisium basin. The lunar mantle contains a seismic discontinuity at ~500 kilometers (310 miles) depth, most likely related to a change in composition. Titan and Triton each have a mantle made of ice or other solid volatile substances.

Asteroids

Some of the largest asteroids have mantles; for example, Vesta has a silicate mantle similar in composition to diogenite meteorites.

See also Earth's internal heat budget Lehmann discontinuity Mantle xenoliths Mantle convection Mesosphere (mantle) Numerical modeling (geology) Primitive mantle

References

Further reading Don L. Anderson, Theory of the Earth, Blackwell (1989), is a textbook dealing with the Earth's interior and is now available on the web. Retrieved 2007-12-23. Jeanloz, Raymond (2000). "Mantle of the Earth". In Haraldur Sigurdsson; Bruce Houghton; Hazel Rymer; John Stix; Steve McNutt (eds.). Encyclopedia of Volcanoes. San Diego: Academic Press. pp. 41–54. ISBN 978-0-12-643140-7. Nixon, Peter H. (1987). Mantle xenoliths: J. Wiley & Sons, 844p., (ISBN 0-471-91209-3). Donald L. Turcotte and Gerald Schubert, Geodynamics, Cambridge University Press, Third Edition (2014), ISBN 978-1-107-00653-9 (Hardback) ISBN 978-0-521-18623-0 (Paperback)

External links

The Biggest Dig: Japan builds a ship to drill to the earth's mantle – Scientific American (September 2005) (archived 17 October 2007) Information on the Mohole Project (archived 2 November 2015)

Worked examples

Example 1 — a first encounter with Mantle (geology)

Start with the simplest possible case. Write down what Mantle (geology) claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In earth science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Mantle (geology) before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Mantle (geology) ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Mantle (geology)

In research: Mantle (geology) appears in earth science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Mantle (geology) in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Mantle (geology) is common in secondary-school and first-year university syllabi. It links to neighbouring topics Planetary geology, Structure of the Earth, so understanding it makes those chapters shorter.
In everyday life: Look for Mantle (geology) outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Mantle (geology)” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Mantle (geology) in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Mantle (geology) means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Mantle (geology) out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Mantle (geology) in simple terms?

A mantle is a layer inside a planetary body bounded below by a core and above by a crust. Mantles are made of rock or ices, and are generally the largest and most massive layer of the planetary body.

Why does Mantle (geology) matter?

Because it connects several earth science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Mantle (geology)?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Mantle (geology).