Our colourful earth

October 19, 2019

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Mother Earth is beautiful in every way. It is full of colours and wonders; the more we read and see, the more we fall in love and get inspired with its beauty as well as mysteries.

The colours of our beautiful earth vary from various hues of greens of plants and trees to the various shades of blue in the sky and in oceans, to amazing earthen tones of rugged mountains, fertile lands and dry deserts. Our earth is a box full of colours waiting to be explored. But have you ever wondered how all these various colours at various places around the world have come into being?

Well, some colours in the natural occurring phenomena happen due to the pigmented bacteria and some after millions of years of sedimentary layering. And today we will explore a few naturally-occurring colourful phenomena around the world.

The Rainbow Mountains of China
The Rainbow Mountains of China

The Rainbow Mountains of China

The Rainbow Mountains of China are in the Zhangye Danxia Landform Geological Park; the area is a geological wonder of the world.

The park is in the Gansu province, covering 200 square miles. It was named a UNESCO World Heritage Site in 2009. You will be wondering what made these mountains so colourful?

Let’s check out why without digging deep into the chemistry and mineralogy behind these colourful rock formations.

To be precise, these colourful rock and sand formations resulted from the combination of the movement of tectonic plates, layered sediments and erosion that took place millions of years ago. Combined with water erosion, freezing, thawing and wind, we got the gift of these colourful mountains.

The Rainbow Mountains are not present in just China, there are three more places, with similar colourful mountains such as Landmannalaugar Mountain in Iceland; Vermilion Cliffs in Arizona, USA and Vinicunca Mountain in Peru.

Seven-coloured earth, Chamarel, Mauritius
Seven-coloured earth, Chamarel, Mauritius

Seven-coloured earth, Chamarel, Mauritius

This is not as broad and long as the other colourful mountain ranges, it is a small area of sand dunes, comprising sands of seven different colours such as red, brown, violet, blue, purple and yellow. The main feature of the place is its different-coloured sands settled in layers, giving the dunes striped-coloured pattern.

So what made the seven colours gather at a small area? Again, we have a bit of a lengthy explanation of chemistry and mineralogy, but this time with volcanic activity taking place underneath.

It is said that the Chamarel plain sand has formed from the decomposition of volcanic rock (basalt) which further transformed into ferralitic soil (the process of rock changing into soil consisting clay esquioxides) by hyderolysis; scientists further elaborate that these various colours of sand are the result of molten volcanic rock cooling down at different temperatures.

Interestingly, as these colours have developed due to different compositions, so if you take handfuls of different colours of the sand from the area and mix them together, they will eventually separate, and each grain of sand will rejoin its colour family. Scientists and researchers still can’t fathom the cause behind the consistent spontaneous separation of sand.

The liquid rainbow, Cano Cristales River, Colombia
The liquid rainbow, Cano Cristales River, Colombia

The liquid rainbow, Cano Cristales River, Colombia

This is also a unique, yet beautifully coloured place you would love to visit. The Caño Cristales is found in Meta’s Serrania de la Macarena province in a remote, isolated area not easily accessible by road; it is 100 km long and features vibrant colours of orange, yellow, red, green and blue.

It is locally called “the river of five colours”. The river’s colours are at their peak between the wet and dry season of the year, likely from July until November. The most vibrant of these colours is red, which is caused by the growth of the Macareniaclavigera, a plant that grows on the bottom of river bed. Macarenia can be of colours anywhere from magenta to bright red, or even bright purple.

What makes the river unique is the complete lack of aquatic animal in its waters. There are some amphibians and reptile species found around the area, but the river itself lacks any kind of fish and molluscs. Researchers claim that the bed of the river lacks necessary nutrients for fauna to survive.

Morning Glory Pool, Yellowstone National Park, Wyoming (US)
Morning Glory Pool, Yellowstone National Park, Wyoming (US)

Morning Glory Pool, Yellowstone National Park, Wyoming (US)

Morning Glory Pool was named in the 1880s for its remarkable colour and similarity to the flower of the same name. Back in the old days, when it was first discovered, the spring had its beautiful hue of blue for its namesake flower ‘morning glory’; this blue hue was the result of thermophilic bacteria, a heat-seeking bacterium found abundantly in the water.

However, the present colouration which has changed to yellow and orange at the edges while green in the centre is the result of people throwing trash in the water. With time, this trash has settled at the bottom and sides of the pool, which has blocked the spring’s vents from releasing the heat, preventing proper circulation. As a result, other microorganisms have infiltrated the pool, changing its delicate ecosystem and colouring.

Today, orange and yellow rings encroach on the blue waters.

Danakil Depression, Northern Ethiopia
Danakil Depression, Northern Ethiopia

Danakil Depression, Northern Ethiopia

This region, and particularly this place, is not only inhospitable, but a poorly studied area in the world. Found in a far off region of Ethiopia, the Danakil depression is situated on an active tectonic plate boundary which is splitting apart the plates at a rate of 7mm per year.

The Danakil is notable for its bright yellow and green deposits of sulphur, salt, potash and other minerals that saturate the Dallol hydrothermal field, a 3,800-square-mile area that is 400 feet below sea level. So when the plates pull apart, hot springs bubble up into acidic pools that form ethereal crystals and pillars as the briny waters evaporate.

Fly geyser, Washoe County, Nevada, US

Geysers are naturally occurring phenomena that takes place around the world. But in this case, this small and brightly coloured geyser is the result of humans’ accidental part in its creation.

It is said that while drilling a well on the land in search of geothermal energy back in 1964, engineers unintentionally gave a way to this geyser. Thus, over the years, the geyser’s mineral rich water consistently sprouts about five feet in the air and this has resulted in the formation of these colourful mounds around the well.

So where did the colours come from? The answer is in the presence of pigmented thermophilic bacteria.

A carpet of flowers in the Atacama Desert, Chile
A carpet of flowers in the Atacama Desert, Chile

Carpet of flowers in the Atacama Desert, Chile

Deserts are harsh places where hardly any living thing survives except for the few sturdy animals or reptiles that are prone to bear such harsh conditions, and this Atacama Desert is no exception as it spends most of its time dry and longing for the rain.

Unfortunately, this desert must wait for six or seven years to have rainfall but when it rains, the place turns into a land of colours. Every inch of the desert becomes covered with the blooms, resulting in a blanket of almost 200 types of flowers.

The rainbow tree
The rainbow tree

Rainbow trees

Eucalyptus is a tree found abundantly across our country and around the world, however, this rainbow eucalyptus (Eucalyptus deglupta) is not very common. It is found in Southeast Asia and Australasia; especially in Indonesia, Papua New Guinea and the Philippines.

So how these vibrant colours accumulate on the bark? According to researchers, the bark on this tree begins as green but as it matures, it turns dark green, purple, rust and orange. So annually, at different times, the inner bark exposes with its fresh and vibrant green colour that turns into blue, purple, orange and red as it matures, thus giving it a colourful look and the name.

Spotted or polka dot lake

The lake lies in the Okanagan region of British Columbia, Canada. It has long been considered a sacred lake by the indigenous people Okanagan, as they believed each and every circles (the spots) have different healing and medicinal properties. However, there is no scientific explanation of the beliefs of the people.

So how do these spots appear? These spots appear during the summer when water evaporates and the lake dons a leopard print made of minerals. The minerals and a collection of salts are present in the surrounding hills which leak into the lake throughout the year.

Thus, the colourful pools are the result of a high concentration of minerals, including calcium, sodium sulphates and magnesium sulphate that have collected in the water. The various colours depend on the concentration of minerals in each pool.

During World War I, minerals from the lake were used to manufacture ammunition. According to the British Columbia Visitor Centre, prior to this mineral mining, the ‘lake displayed an even greater variety of colours and an even greater artistic beauty’.

Published in Dawn, Young World, October 19th, 2019