A reminder of turbulent times: the emergence of the Devil's Tower on Earth—when and how it happened (with photos).

The history of the Earth spans over 4.5 billion years, during which an astonishing number of extraordinary reminders of past events have emerged on the planet. One such place is the Devil's Postpile, located in the southwestern part of California — scientists have explained how it came to be, as reported by IFLScience.

Situated within a national monument named in its honor, the Devil's Postpile consists of a columnar basalt rock formation, a type of rock created by the rapid cooling of lava. Some of these columns appear to be lying on their sides, while others reach heights of up to 18.3 meters and are closely packed together. Nonetheless, they all serve as reminders of the region's turbulent history.

Researchers note that what is now known as the Devil's Postpile began its journey as a lava lake approximately 80,000 to 100,000 years ago. It is known that at some point during this time, an opening formed in the Earth's crust north of where the monument currently stands, releasing scalding basaltic lava — a particularly fluid form of hot material that covered the surrounding landscape.

Eventually, the lava encountered a natural slab, resulting in the formation of an unusually deep lava lake. For instance, in some areas, its depth reaches about 122 meters, which is greater than the average depth of all the Great Lakes.

According to scientists, when lava cools rapidly and solidifies, it contracts, which can lead to the formation of unloading cracks known as joints. These joints are most effective at relieving stress when there are three of them intersecting at angles of 120° — this is what often causes columnar basalt to have a hexagonal shape.

It is known that the "columnar" aspect arises from the fact that the joints begin at a cooler surface and then extend downward to the base. Scientists believe this process allows the warmer rock to cool down more quickly.

Tens of thousands of years ago, when the towers first emerged, the formation was likely significantly larger than it is today. Scientists believe that glaciers, which carved the land numerous times throughout history, are responsible for the current appearance of the Devil's Postpile.

Why the formation is called the Devil's Postpile

According to American researcher Theola Solomon, the name was likely coined by shepherds who lived in the area and thought the columns resembled wooden fence posts.

However, by the time it was designated as part of a national monument in 1911, "woodpile" had transformed into "postpile," and "Devil’s" became simply "Devil" — although later the "s" was restored, but without the apostrophe.