Chicxulub - a crater on the Yucatan Peninsula: size, origin, history of discovery

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Chicxulub - a crater on the Yucatan Peninsula: size, origin, history of discovery
Chicxulub - a crater on the Yucatan Peninsula: size, origin, history of discovery

Video: Chicxulub - a crater on the Yucatan Peninsula: size, origin, history of discovery

Video: Chicxulub - a crater on the Yucatan Peninsula: size, origin, history of discovery
Video: Meteor Impact Site | National Geographic 2024, May
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Many of us have heard of the Tunguska meteorite. At the same time, few people know about his brother, who fell to Earth in time immemorial. Chicxulub is a crater formed after a meteorite fell 65 million years ago. His appearance on Earth led to serious consequences that affected the entire planet as a whole.

Where is the Chicxulub crater?

It is located in the northwestern region of the Yucatan Peninsula, as well as at the bottom of the Gulf of Mexico. With a diameter of 180 km, the Chicxulub crater claims to be the largest meteorite crater on Earth. Part of it is on land, and the second part is under the waters of the bay.

Discovery history

The opening of the crater was random. Since it has a huge size, they did not even know about its existence. Scientists discovered it quite by accident in 1978 during geophysical surveys of the Gulf of Mexico. The research expedition was organized by Pemex (full name Petroleum Mexican). She faced a difficult task - to find oil fieldsat the bottom of the bay. Geophysicists Glen Penfield and Antonio Camargo, during their research, first discovered a stunningly symmetrical seventy-kilometer arc under water. Thanks to the gravity map, scientists have found a continuation of this arc on the Yucatan Peninsula (Mexico) near the village of Chicxulub.

chicxulub crater
chicxulub crater

The name of the village is translated from the Mayan language as "tick demon". This name is associated with an unprecedented number of insects in this region since ancient times. It was the consideration of the Yucatan Peninsula on the map (gravitational) that made it possible to make many assumptions.

Scientific substantiation of the hypothesis

Close together, the found arcs form a circle with a diameter of 180 kilometers. One of the researchers named Penfield immediately suggested that this was an impact crater that appeared as a result of a meteorite fall.

His theory turned out to be correct, which was confirmed by some facts. A gravitational anomaly was found inside the crater. In addition, scientists have discovered samples of "shock quartz" with a compressed molecular structure, as well as glassy tektites. Such substances can be formed only at extreme pressure and temperature values. The fact that Chicksculub is a crater, which has no equal on Earth, was no longer in doubt, but irrefutable evidence was needed to confirm the assumptions. And they were found.

yucatan on the map
yucatan on the map

Scientifically confirm the hypothesis managed by the professor of the department of the University of Calgary Hildebrant in 1980 thanks tostudy of the chemical composition of the rocks of the area and detailed satellite imagery of the peninsula.

The consequences of a meteorite fall

Chicxulub is believed to be a meteorite impact crater with a diameter of at least ten kilometers. Scientists' calculations show that the meteorite was moving at a slight angle from the southeast. His speed was 30 kilometers per second.

The fall of a huge cosmic body to Earth happened about 65 million years ago. Scientists suggest that this event happened just at the turn of the Paleogonian and the Cretaceous period. The consequences of the impact were catastrophic and had a huge impact on the further development of life on Earth. As a result of a meteorite impact with the earth's surface, the largest crater on Earth was formed.

largest crater on earth
largest crater on earth

According to scientists, the power of the impact exceeded several million times the power of the atomic bomb dropped on Hiroshima. As a result of the impact, the largest crater on Earth was formed, surrounded by a ridge, the height of which was several thousand meters. But soon the ridge collapsed due to earthquakes and other geological transformations provoked by a meteorite impact. According to scientists, a tsunami began from a powerful blow. Presumably the height of their waves was 50-100 meters. The waves went to the continents, destroying everything in their path.

Global cooling on the planet

The shock wave went around the entire Earth several times. With its high temperature, it caused the strongest forest fires. in differentregions of the planet activated volcanism and other tectonic processes. Numerous volcanic eruptions and the burning of large forest areas have led to the fact that a huge amount of gases, dust, ash and soot have entered the atmosphere. It's hard to imagine, but the raised particles caused the process of volcanic winter. It lies in the fact that most of the solar energy is reflected by the atmosphere, resulting in global cooling.

impact crater
impact crater

Such climatic changes, along with other severe consequences of the impact, had a detrimental effect on the living world of the planet. Plants did not have enough light for photosynthesis, which led to a decrease in oxygen in the atmosphere. The disappearance of a huge part of the Earth's vegetation led to the death of animals that lacked food. It was these events that led to the complete extinction of dinosaurs.

Cretaceous-Paleogene extinction

The fall of a meteorite is currently considered the most convincing reason for the mass death of all life in the Cretaceous-Paleogene period. The version about the extinction of living beings took place even before the Chicxulub (crater) was discovered. And one could only guess about the reasons that caused the cooling of the climate.

Scientists have found a high content of iridium (a very rare element) in sediments that are approximately 65 million years old. An interesting fact is that a high concentration of the element was found not only in the Yucatan, but also in other places on the planet. Therefore, experts say that, most likely, there was ameteor shower.

On the border of the Paleogene and Cretaceous, all dinosaurs, flying lizards, marine reptiles, which reigned for a long time in this period, died out. All ecosystems were completely destroyed. In the absence of large pangolins, the evolution of birds and mammals accelerated, the species diversity of which increased significantly.

yucatan mexico
yucatan mexico

According to scientists, it can be assumed that other mass extinctions were triggered by the fall of large meteorites. Available calculations allow us to say that large cosmic bodies fall to the Earth once every hundred million years. And this roughly corresponds to the length of time between mass extinctions.

What happened after the meteorite fell?

What happened on Earth after the meteorite fell? According to paleontologist Daniel Durd (Colorado Research Institute), in minutes and hours, the lush and flourishing world of the planet turned into a devastated land. Thousands of kilometers from the place where the meteorite fell, everything was completely destroyed. The impact claimed the lives of more than three-quarters of all living things and plants on Earth. It was the dinosaurs that suffered the most, they all became extinct.

For a long time, people did not even know about the existence of the crater. But after it was found, it became necessary to study it, since scientists have accumulated many hypotheses that need to be verified, questions and assumptions. If you look at the Yucatan Peninsula on a map, it is difficult to imagine the actual size of the crater on the ground. The northern part is far fromshores and covered by 600 meters of ocean sediments.

consequences of a meteorite fall
consequences of a meteorite fall

In 2016, scientists began drilling in the area of the marine part of the crater in order to extract core samples. Analysis of the extracted samples will shed light on events that happened a long time ago.

Events since the disaster

The fall of an asteroid vaporized a huge part of the earth's crust. Over the crash site, debris soared into the sky, fires and volcanic eruptions broke out on Earth. It was the soot and dust that blocked the sunlight and plunged the planet into a very long period of winter darkness.

During the following months, dust and debris fell to the earth's surface, covering the planet in a thick layer of asteroid dust. It is this layer that is, for paleontologists, evidence of a turning point in the history of the Earth.

The area of North America before the meteorite impact flourished lush forests with a dense undergrowth of ferns and flowers. The climate in those days was much warmer than today. There was no snow at the poles, and dinosaurs roamed not only in Alaska, but also in the Seymour Islands.

The consequences of a meteorite impact on the ground, scientists studied by analyzing the Cretaceous-Paleogene layer, found in more than 300 places around the world. This gave reason to say that all living things died near the epicenter of events. The opposite part of the planet suffered from earthquakes, tsunamis, lack of light and other consequences of the disaster.

Those living creatures that did not die immediately, died from lack of water and food, destroyed by acid rain. Doomvegetation led to the death of herbivores, from which carnivores also suffered, left without food. All links in the chain have been broken.

New assumptions of scientists

According to scientists who studied fossils, only the smallest creatures (like raccoons, for example) could survive on Earth. It was they who had a chance to survive in those conditions. Because they eat less, they reproduce faster and adapt more easily.

crater opening
crater opening

Fossils suggest that Europe and North America had a more favorable situation after the disaster than elsewhere. Mass extinction is a dual process. If something has died on one side, something has to arise on the other side. Scientists think so.

Restoring the Earth has taken a very long time. Hundreds, if not thousands of years passed before ecosystems were restored. It is estimated that it took the oceans three million years to restore normal life to organisms.

After strong fires, ferns settled in the ground, quickly populating the burnt regions. Those ecosystems that escaped the fire were inhabited by mosses and algae. The areas least affected by the destruction became places where some species of living creatures could survive. Later they spread all over the planet. So, for example, sharks, some fish, crocodiles survived in the oceans.

The complete extinction of the dinosaurs opened up new ecological niches for other creatures to occupy. Subsequently, the migration of mammals to vacated areas led to their modernabundance on the planet.

New information about the past of the planet

Drilling the world's largest crater, located in the Yucatan Peninsula, and taking more and more samples will allow scientists to get more data on how the crater was formed and the consequences of the fall on the formation of new climatic conditions. Samples taken from the inside of the crater will allow experts to understand what happened to the Earth after the strongest impact and how life was restored in the future. Scientists are interested in understanding how the restoration took place and who returned first, how quickly the evolutionary diversity of forms appeared.

chicxulub crater with a diameter of 180 km
chicxulub crater with a diameter of 180 km

Despite the fact that certain species and organisms died, other forms of life began to flourish doubly. According to scientists, such a picture of a disaster on the planet could be repeated many times over the entire history of the Earth. And each time, all living things perished, and in the future, recovery processes took place. It is likely that the course of history and development would have been different if the asteroid had not fallen on the planet 65 million years ago. Experts also do not exclude the possibility that life on the planet was born due to the fall of large asteroids.

Instead of afterword

The impact of the asteroid caused the strongest hydrothermal activity of the Chicxulub crater, which most likely lasted 100,000 years. She could enable hypermatophiles and thermophiles (these are exotic single-celled organisms) to thrive in hot environments by settling inside the crater. This hypothesis of scientists, of course,needs verification. It is rock drilling that can help shed light on many events. Therefore, scientists still have many questions that need to be answered by studying Chicxulub (crater).

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