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How is Cave Coral Formed?

How is Cave Coral Formed?

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How is Cave Coral Formed?

Cave Coral? Isn’t coral something you normally find in the water? Well, cave formations are generally formed when an acid reacts to limestone, or the rocks contain over 80% calcium carbonate. The formations normally grow on the ceiling, walls, and floors of the cave and are sometimes influenced by humidity, airflow, and temperature.

How Is Cave Coral Formed?

The more scientific name for formations are speleothems and are formed from the Greek word “spelaion,” which means deposit. However, many elements have to be in place for speleothems forms in a select environment. To have the formations growing faster and more efficiently, the rocks generally have to be limestone, dolomite, or other rocks similar in nature.

How Is Cave Coral Formed?

Also, rainfall plays a critical role, an average of more than 500 mm annually. Vegetation is also critical in helping cave formation develop as they help produce more acid needed to enhance the process. 

When rain falls, the cave’s cracks and joints see a lot of water seeping through, which contributes to forming the formations. When the rainwater mixes with carbon dioxide, a weak acid is created known as carbonic acid. When this weak acid comes in contact with the limestone, it tends to dissolve in it.

Whenever this happens, the cracks and joints in the rocks tend to get larger. Even though the acid can remain consistent, the acid gets stronger, especially seeing the carbon dioxide absorbed from vegetation is gradually increased. Once all these processes combine and go over a few years, you will see some rather interesting formations. Different formations are commonly called cave pearls, rimstone pools, columns, bacon strips, stalagmites, and stalactites.

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What Is Cave Coral and How Is It Formed?

I’m sure you have been in at least one cave before or have done some research on this part of nature’s wonder. During some of those tours, you may have noticed some strange patches and wonder what they are. Well, you could very well be looking at some cave corals. So, what are these? They are tiny speleothems that come with short stalks with bulging ends.

They usually appear collectively, so you will generally see them in patches. These corals consist of calcite and also concentric rings, as you can see pictured here. From all indications, it is evident corals form in the same way as dripstones. However, among the interesting features of cave corals is that they ignore everything about gravity and grow in whatever direction they feel. 

Photo credit: Caver59 on DeviantArt

To date, not many legitimate details have been presented about how these cave corals are formed, but one thing is evident…the factors present in the cave are critical to their existence. Based on numerous research and investigations, many theories have concluded that these corals are formed based on water being present in the cave.

Bear in mind, water levels rise and fall in caves, and the temperature is adjusted as this happens. Whenever excess water floods through the cave, calcite flows and grows against the walls. Instead of these attachments growing bigger, they only get re-coated with more calcite each time there is a water rush through caves. 

Every time this happens, the crystals get layered and eventually become corals. It sounds a bit logical, but so much additional research is needed to further light on how they truly come about. Also, other theories note that they get bigger and bigger (even though not too big) as the temperatures get warmer each time.

But, amidst everything known and unknown about cave corals, we can safely say they are a habitat for many cave critters and crawlers. Who knows what other benefits they may have to provide us with? Let’s wait on the research to get rolling!

Cave Coral Fun Fact:

One of the best parts is that cave corals are formed in “land caves” and underwater caves. For instance, the scientific discovery of Mediterranean red corals in an underwater cave off the southern coast of France. Interestingly, only a few places in the entire Mediterranean have these red cave corals making them extra special. While more research is ongoing, you will love to see and learn more about these corals. 

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