These stunning satellite images look like abstract art – and reveal a lot about our planet

Ecologists find that plants, animals, and phenomena rarely do the rest of us. In this series, we invited them to share their unique photos from the field.

There is something to be said for a job that pays you to wander the Scottish Highlands, roam around a Greek island, or go on an expedition to Antarctica – all in the name of geoscience, the study of the Earth.

But during the travel restrictions due to the Corona virus, many geologists have had to extract samples and data they already have. Other geologists have used satellite images and other images to make geological explanations.

This geological field is called remote sensing, and it is the process of using, for example, satellites or aircraft to observe the physical features of an area at a distance. It is often easier to see how geology shapes our landscapes by taking this viewpoint.

In great news for remote sensing geologists, chair geologists, and scenic enthusiasts, the USGS has a wealth of satellite images of Earth’s surface, capturing stunning geological features from space.

Remote sensing geologists use several techniques that make features of interest even more distinct. This enhances or alters the colors, which you can see in a few of my picks from the eight most amazing photos from the USGS. This is what they reveal about the planet.

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volcanoes from space

Volcanoes are usually very distinctive when you see them from Earth, whether it’s the famous Mount Fuji, the lava fields of Iceland, or the hundreds of volcanoes that dot the fields of Western Victoria in Australia.

From above, it can look a little different. In the first image below of Mount Elgon on the Uganda-Kenya border, you can identify the “caldera” – a bowl-shaped depression in the center of the volcano where rocks collapsed after the magma chamber emptied.

In the second image of Mount Taranaki in New Zealand, you can spot the crater, which is also a depression, but it forms when a volcano erupts and rocks spurt out.

Mount Elgon, Uganda and Kenya.
USGS / Unsplash
Crater from above surrounded by a dark green circle of the forest
Mount Taranaki in Egmont National Park, New Zealand.
USGS / Unsplash

Volcanic products may also be visible in satellite images. You can see the lava flow from the Harouge volcano in Libya in the third image below. It’s a black speck of basalt on the surrounding white and yellow sand, to envy even the best of Rorschach ink spots.

This lava field is about 185 kilometers wide, a large distance possible because the chemical composition of the lava made it liquid and able to flow a long distance from the site of the eruption.

Black patches of lava in the surrounding sandy desert landscape
Al-Harouj volcanic field, Libya.
USGS / Unsplash

Some features related to magma have puzzled geologists for years. Only by combining remote sensing and observations on Earth were they able to solve these geological puzzles. The Richat structure in the Mauritanian Mor Adrar Desert, shown below, is one such feature.

It looks like a meteorite crater or perhaps an intergalactic visitor center point. But in recent years, researchers have determined – after much controversy – that it formed when a series of magma from deep within the surface entered existing sediments.

Concentric gray rocky rings surrounded by a green landscape from above
Rishat structure, Mauritania.
USGS / Unsplash

Some of this magma has formed concentric circles, known as annular dams, which is the main feature we see in satellite images. This annular dam magma never reached the surface and is only now exposed because the rock above it has eroded over time.

But other magma in the chain has managed to surface to erupt as lava. You can see the small volcano that formed from these surface eruptions on the USGS image as it appears as a grayish-white spot that cuts through the southwestern part of the Inner Ring Dam.

Read more: Pictures from the field: Stunning crystals reveal deep secrets about Australian volcanoes

When rocks collide

The landscape of Iran’s Zagros Mountains and China’s Kiping Shan thrust range have two main things in common.

First, they both look great from the top. Second, they both formed on the ocean floor and then were lifted and deformed by geological forces to form the hills and valleys that dominate these two regions today.

View from the top of the rocky domes between the valleys
Zagros Mountains, Iran.
USGS / Unsplash
Landscape from above showing multicolored layers of rock that have been folded and disintegrated
Push belt Keping Shan, China.
USGS / Unsplash

Both mountain belts were created when clumps of land collided, and the pressure from these collisions caused the rocks to break against themselves. In some places, the rocks have completely shattered.

These fractures, known as faults, create deeper and older rocks to sit on top of smaller rocks. These faults form the stratigraphic protuberances seen in the Keping Shan satellite image.

Unlike Kiping Shan, ridges in the Zagros Mountains were formed when soft rocks, such as silt and mudstone, eroded over time. This erosion formed valleys next to the more resistant rocks of limestone and dolomite, which form the folded domes in the form of an arc.

rivers disintegrate

Rivers bring about huge changes in our landscapes. Over many years they can find weaknesses in rocks and exploit them to make their way across any terrain. Rivers look and behave differently depending on factors such as their flow rate, the amount of sediment they carry, and the slope gradient they are on.

Rivers can consist of a single, narrow, winding stream (called a meandering river) like the Beni River in Bolivia, or a wide channel consisting of many branches braided together between sediment rods (called a braided river), like the part of the Brazilian Río Negro in the last photo below.

A meandering blue river cuts through a bright green forest
Brown River, Bolivia.
USGS / UnsplashCC BY
A view from the top of the blue Rio Negro (Black River) with a mosaic of rivers surrounded by green plains.
Rio Negro, Brazil.
USGS / UnsplashCC BY

Looking at the meandering Beni River from above, you can see how the river’s twists and turns have evolved over time. The U-shaped lakes scattered along the edges of the river are called oxbow lakes.

These Rainbow Lakes are the former channel of the river that has since been cut off when the river eroded a new, more direct channel that must be followed. In Australia, oxbow lakes are also known as billabong.

In contrast to the slowly meandering Beni River, the wide channel of the Rio Negro is created by rapid flows and deposition of coarse sediments. These characteristics form a mosaic of small islands between branching water flows. The islands are flooded during the rainy season in Brazil when the volume and flow of water are highest.

Armed with this new knowledge, book a window seat the next time you fly and see the geological wonders you can spy on from above.

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