The “oldest” of the Earth’s “effect crater” is much younger than previously thought to be found during a new study

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Have you ever been late because you read the clock wrong? Occasionally, “watch” geologists use events so far, and can also be mistakenly read. Earthing for 4.5 billion years with rock is a complex business.

Example: Recently, an ancient meteorite impact crater has been reported in the remote Western Australian Pilbara region. The original investigation, conducted by another group, filed headlines with a lawsuit that the crater made 3.5 billion years ago. If true, it would be the oldest land.

As it turns out, we also researched the same site. Our results are published today by Science Advances. Although we agree that this is an ancient meteorite effect, we have made different conclusions about its age, size and significance.

Let’s consider the statements about this charming crater.

One -effect crater, two versions of events

Planetary researchers are looking for ancient effects to learn about early land formation. So far, no one has found the structure of Yarrabbba over 2.23 billion years as well as Australia. (Some of the authors of the Pilbara research of 2025 were co -authors of Yarrabubba in 2020.)

The new rival is located in the district called the North Pole Dome. Despite the name, it is not where Santa lives. It is a dry, hot, ocher painted landscape.

The first report of the new crater states that it was 3.5 billion years and was more than 100 kilometers in diameter. It was suggested that such a major effect may have influenced the formation of the continental crust in Pilbara. I also speculated, investigators also said it could have influenced early life.

Our study concludes that the effect actually occurred much later, 2.7 billion years ago. This is at least 800 million years younger than the previous rating (and we think it’s probably even younger; more about it instantly).

We also found that the crater was much smaller – about 16 km in diameter. In our opinion, this effect was too young and too small to affect the formation of the continent or early life.

So how could two studies make such different conclusions?

Subtle impact clues

Initially, a circular crater is deeply eradicated, leaving only subtle clues in the landscape. However, among the rust color basalt are unique meteorite stroke signal signs: cones crashed.

Shatter cones are the exceptional fossilistic shock waves passed through the rocks. Their unique conical forms are formed under short but tremendous pressure when a meteorite strikes the Earth.

Both studies have shown broken cones and agree that the site is ancient effect.

This new crater also needed a name. We consulted Nyamal, the local Aboriginal people who shared the traditional name of this place and its people: Miralga. The name “Miralga Impact Structure” recognizes this heritage.

Determination of exposure time

The age of the impact was evaluated by observing the field because no study found in a study that can cause age -related radiometric dating – a method that uses radioactive isotope measurements.

Both studies applied a geological principle called the Superposition Act. It says that the rocks settle on top of each other over time, so the rocks at the top are younger than below.

The first group found broken cones and under the sediment layer, which was known to be deposited 3.47 billion years ago, but there were no trembling cones in younger rocks above this layer. This meant that the effect occurred with a deposited layer of sediment.

Their observation seemed to be a “smoking gun” 3.47 billion years ago.

As it turns out, there were more in history.

Our study found that Shatter cones were the same 3.47 billion years of rocks, but also in younger upper rocks, including lava, known that it had erupted 2.77 billion years ago.

The effect was to occur after the youngest rock that had broken cones were formed, which means ever after 2.77 billion years of lava.

At the moment we do not know exactly how young the crater is. We can only limit the impact that had between 2.7 billion and 400 million years. We try to see the methods of isotope, but these results are not yet.

Smaller than thought to be initially

We created the first map that shows where the cones were found. There are many hundred in 6 km. From this map and their orientations, we estimate that the original crater was about 16 km in diameter.

The 16 km crater is far from the initial than 100 km. It is too small to affect the formation of continents or life. Pilbara was already quite old before the impact.

A new connection with Mars

Science is a self -service sport. At that time, the available data are based on discovery statements, but they often require modification based on new data or observations.

Although not the oldest in the world, the effect of Miralga is scientifically unique, as the basalte craters are rare. Many of the Basalt there were 3.47 billion years, making them the oldest shocked rocks.

Until the impact, these ancient basaltes were chemically replaced by sea water. Nearby sediment rocks are also the earliest well -known fossils on Earth. Such rocks probably covered most of the early land and Mars.

This does the Miralga impact structure at the playground for planets researchers investigating the surface of Mars (and maybe early life). It is an easily accessible place for proof of Mars exploration instruments and images, here on Earth.

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