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Visualizing the Scale and Composition of the Earth’s Crust

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Visualizing the Scale and Composition of the Earth’s Crust

For as long as humans have been wandering the top of Earth’s crust, we’ve been fascinated with what’s inside.

And Earth’s composition has been vital for our advancement. From finding the right kinds of rocks to make tools, all the way to making efficient batteries and circuit boards, we rely on minerals in Earth’s crust to fuel innovation and technology.

This animation by Dr. James O’Donoghue, a planetary researcher at the Japan Aerospace Exploration Agency (JAXA) and NASA, is a visual comparison of Earth’s outer layers and their major constituents by mass.

What is the Composition of Earth’s Crust?

The combined mass of Earth’s surface water and crust, the stiff outermost layer of our planet, is less than half a percent of the total mass of the Earth.

There are over 90 elements found in Earth’s crust. But only a small handful make up the majority of rocks, minerals, soil, and water we interact with daily.

1. Silicon

Most abundant in the crust is silicon dioxide (SiO2), found in pure form as the mineral quartz. We use quartz in the manufacturing of glass, electronics, and abrasives.

Why is silicon dioxide so abundant? It can easily combine with other elements to form “silicates,” a group of minerals that make up over 90% of Earth’s crust.

Clay is one of the better-known silicates and micas are silicate minerals used in paints and cosmetics to make them sparkle and shimmer.

MineralMajor ElementsPercentage of Crust
Plagioclase FeldsparO, Si, Al, Ca, Na39%
Alkali FeldsparO, Si, Al, Na, K12%
QuartzO, Si12%
PyroxeneO, Si, Mg, Fe11%
AmphiboleO, Si, Mg, Fe5%
Non-silicatesVariable8%
MicasO, Si, Al, Mg, Fe, Ca, Na, K5%
Clay MineralsO, Si, Al, Mg, Fe, Ca, Na, K5%
Other SilicatesO, Si3%

2. Aluminum and Calcium

SiO2 bonds very easily with aluminum and calcium, our next most abundant constituents. Together with some sodium and potassium, they form feldspar, a mineral that makes up 41% of rocks on Earth’s surface.

While you may not have heard of feldspar, you use it every day; it’s an important ingredient in ceramics and it lowers the melting point of glass, making it cheaper and easier to produce screens, windows, and drinking glasses.

3. Iron and Magnesium

Iron and magnesium each make up just under 5% of the crust’s mass, but they combine with SiO2 and other elements to form pyroxenes and amphiboles. These two important mineral groups constitute around 16% of crustal rocks.

Maybe the best known of these minerals are the two varieties of jade, jadeite (pyroxene) and nephrite (amphibole). Jade minerals have been prized for their beauty for centuries, and are commonly used in counter-tops, construction, and landscaping.

Some asbestos minerals, now largely banned for their cancer-causing properties, belong to the amphibole mineral group. They were once in high demand for their insulating and fire-retardant properties and were even used in brake pads, cigarette filters, and as artificial snow.

4. Water

Surprisingly, even though it covers almost three quarters of Earth’s surface, water (H2O) makes up less than 5% of the crust’s mass. This is partly because water is significantly less dense than other crustal constituents, meaning it has less mass per volume.

Breaking Earth’s Crust Down by Element

Though there are many different components that form the Earth’s crust, all of the above notably include oxygen.

When breaking down the crust by element, oxygen is indeed the most abundant element at just under half the mass of Earth’s crust. It is followed by silicon, aluminum, iron, calcium, and sodium.

All other remaining elements make up just over 5% of the crust’s mass. But that small section includes all the metals and rare earth elements that we use in construction and technology, which is why discovering and economically extracting them is so crucial.

What Lies Below?

As the crust is only the outermost layer of Earth, there are other layers left to contemplate and discover. While we have never directly interacted with the Earth’s mantle or core, we do know quite a bit about their structure and composition thanks to seismic tomography.

The Upper Mantle

At a few specific spots on Earth, volcanic eruptions and earthquakes have been strong enough to expose pieces of the upper mantle, which are also made of mostly silicates.

The mineral olivine makes up about 55% of the upper mantle composition and causes its greenish color. Pyroxene comes in second at 35%, and calcium-rich feldspar and other calcium and aluminum silicates make up between 5–10%.

Going Even Deeper

Beyond the upper mantle, Earth’s composition is not as well known.

Deep-mantle minerals have only been found on Earth’s surface as components of extra-terrestrial meteorites and as part of diamonds brought up from the deep mantle.

One thing the lower mantle is thought to contain is the silicate mineral bridgmanite, at an abundance of up to 75%. Earth’s core, meanwhile, is believed to be made up of iron and nickel with small amounts of oxygen, silicon, and sulphur.

As technology improves, we will be able to discover more about the mineral and elemental makeup of the Earth and have an even better understanding of the place we all call home.

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This article was published as a part of Visual Capitalist's Creator Program, which features data-driven visuals from some of our favorite Creators around the world.

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Mining

Visualizing Raw Steel Production in 2023

China produces more than half the world’s steel.

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Voronoi graphic showing top raw steel producers in 2023.

Visualizing Raw Steel Production in 2023

This was originally posted on our Voronoi app. Download the app for free on iOS or Android and discover incredible data-driven charts from a variety of trusted sources.

Steel is essential for the economy due to its crucial role in infrastructure, construction, manufacturing, and transportation sectors.

This graphic breaks down the estimated global production of raw steel in 2023. The data was sourced from the U.S. Geological Survey as of January 2024.

China Produces More Than Half the World’s Steel

One major issue facing the steel industry is overcapacity in top producer China.

Steel production in China has surpassed demand in recent years, leading to downward pressure on the profit margins of steel mills worldwide.

Historically, China’s troubled real estate sector has accounted for over one-third of the country’s steel consumption. To address this issue, the Chinese government has mandated steel production cuts since 2021.

Far behind China, India is the second-biggest producer of steel, followed by Japan.

CountryRegion2023 Production (million tonnes)
🇨🇳 ChinaAsia1,000
🇮🇳 IndiaAsia140
🇯🇵 JapanAsia87
🇺🇸 U.S.North America80
🇷🇺 RussiaEurope75
🇰🇷 S. KoreaAsia68
🌍 Rest of World420
Total1,870

Infinite Recyclability

Steel is an alloy primarily composed of iron ore containing less than 2% carbon, 1% manganese, and other trace elements. It is 1,000 times stronger than iron and can be recycled over and over without sacrificing quality.

Steel is widely used in various industries. It is a fundamental material in construction, providing support through beams, internal structures, and roofing.

Moreover, steel’s corrosion-resistant properties make it ideal for water infrastructure. Stainless steel pipes are the preferred choice for underground water systems, ensuring longevity and purity in water transportation.

Additionally, most canned foods are stored in steel containers for preservation, as steel does not rust.

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