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

Many of us have heard of the Tunguska meteorite. At the same time, few know about his brother who fell to Earth in time immemorial. Chicxulub is a crater formed after the fall of a meteorite 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 north-western region of the Yucatan Peninsula, as well as on the bottom of the Gulf of Mexico. The Chicxulub crater with a diameter of 180 km 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.

History of the discovery

The opening of the crater was of an accidental nature. Since it has the largest dimensions, it was not even known about its existence. It was discovered by scientists quite accidentally in 1978 during the geophysical research of the Gulf of Mexico. The research expedition was organized by Pemex (full name Petrolium Mexican). Before it there was an uneasy task - to find oil deposits on the bottom of the bay. Geophysicists Glen Penfield and Antonio Camargo in the course of research first discovered a stunningly symmetrical seventy-kilometer arc under the water. Thanks to the gravitational map, scientists found a continuation of this arc on the Yucatan Peninsula (Mexico) near the village of Chicxulub.

The name of the village is translated from the Maya language as "demon mites". This name is associated with an unprecedented number of insects in this region since ancient times. It is the consideration of the Yucatan peninsula on the map (gravitational) that made many assumptions.

Scientific substantiation of the hypothesis

Having closed, the found arcs form a circle, the diameter of which is 180 kilometers. One of the researchers named Penfield immediately suggested that this is a shock crater, which appeared due to the fall of the meteorite.

His theory proved to be true, which was confirmed by certain facts. Inside the crater, a gravitational anomaly was found . In addition, scientists have discovered samples of "shock quartz", having a compressed molecular structure, as well as vitreous tektites. Such substances can be formed only at extreme values of pressure and temperature. The fact that Chiksculub is a crater, which has no equal on the Earth, did not cause doubts, but irrefutable evidence was needed to confirm the assumptions. And they were found.

The hypothesis was scientifically confirmed by the professor at the University of Calgary Hildebrant in 1980, thanks to the study of the chemical composition of the rocks and detailed space imagery of the peninsula.

Consequences of falling meteorite

It is believed that Chicxulub is a crater formed when a meteorite falls, whose diameter is not less than ten kilometers. Calculations of scientists show that the meteorite moved at a slight angle from the southeast. Its speed was 30 kilometers per second.

The fall of the largest cosmic body to Earth occurred approximately 65 million years ago. Scientists suggest that this event occurred just at the turn of the Paleogon and Cretaceous period. The consequences of the blow were catastrophic and had a tremendous impact on the further development of life on Earth. As a result of collision of a meteorite with an earth's surface the largest crater on the Earth was formed.

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 whose height was several thousand meters. But in a short time the ridge collapsed because of earthquakes and other geological transformations, provoked by a meteorite impact. According to scientists, the tsunami started 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 whole Earth several times. Having a high temperature, it caused severe forest fires. In different regions of the planet, volcanism and other tectonic processes intensified. Numerous volcanic eruptions and the burning of large forest areas have resulted in a huge amount of gases, dust, ash and soot entering the atmosphere. It is difficult to imagine this, but the particles raised caused a process of volcanic winter. It consists in the fact that most of the solar energy is reflected by the atmosphere, resulting in a global cooling.

Such climatic changes along with other severe consequences of the impact had a disastrous 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 did not have enough food. It was these events that led to the complete extinction of dinosaurs.

Extinction at the boundary of the Cretaceous and Paleogene period

The fall of the meteorite is now considered the most convincing cause of the mass death of all living things in the Cretaceous-Paleogene period. The version of extinction of living creatures took place even before Chiclubul (crater) was discovered. And the reasons that caused the cold climate, you could only guess.

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

At the border of the Paleogene and Chalk, all dinosaurs, flying lizards, sea reptiles, who reigned for a long time in this period, died out. Absolutely all ecosystems were destroyed. In the absence of large pangolins, the evolution of birds and mammals accelerated, the species diversity of which increased significantly.

According to scientists, it can be assumed that other mass extinctions were triggered by the fall of large meteorites. The available calculations make it possible to say that large cosmic bodies fall to Earth once per hundred million years. And this roughly corresponds to the time intervals between mass extinctions.

What happened after the fall of the meteorite?

What happened on Earth after the fall of the meteorite? According to paleontologist Daniel Durd (Colorado Research Institute), in minutes and hours the magnificent and blooming world of the planet turned into a devastated land. In thousands of kilometers from the place where the meteorite fell, everything was completely destroyed. The blow has claimed the lives of more than three-quarters of all living beings and plants on Earth. The most affected were the dinosaurs, they all died out.

For a long time people did not even know about the existence of the crater. But after he was found, there was a need for his research, because scientists have accumulated many hypotheses that need verification, questions and assumptions. If you look at the Yucatan peninsula on the map, it is difficult to imagine the actual size of the crater on the terrain. Its northern part is far from the coast and is covered by 600 meters of oceanic sediments.

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

Events that took place after the disaster

The fall of the asteroid has evaporated a huge part of the earth's crust. Over the place of the fall, debris soared into the sky, fires and volcanic eruptions flared up on Earth. It was soot and dust that closed 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 with a dense layer of asteroid dust. It is this layer that is for paleontologists the evidence of a turning point in the history of the Earth.

In the region of North America before the impact of the meteorite flourished lush forests with a dense undergrowth of ferns and flowers. The climate in those distant times was much warmer than this. At the poles there were no snows, and dinosaurs wandered not only along Alaska, but also on the Seymour Islands.

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

Those living beings that did not die immediately, were dying from the lack of water and food, destroyed by acid rain. The death of vegetation has led to the death of herbivores, from which the carnivores also suffered, without food. All the links in the chain were broken.

New assumptions of scientists

According to scientists who studied fossils, only the smallest creatures (like raccoons, for example) could survive on Earth. They had a chance to survive in those conditions. Since they eat less, they reproduce faster, and they are easier to adapt.

Fossils indicate that in Europe and North America there was a more favorable situation after the disaster, rather than in other places. Mass extinction is a dual process. If, on the one hand, something is lost, there must be something on the other side. So scientists consider.

The restoration of the Earth took a very long time. Hundreds, or even thousands of years, passed before ecosystems were restored. Presumably, the oceans took three million years to restore the normal life of organisms.

After strong fires, ferns settled in the ground, quickly populating the burned regions. Those ecosystems that escaped fire were inhabited by mosses and algae. The regions that were least affected by the devastation became places in which some species of living beings could survive. Later they settled all over the planet. So, for example, in the oceans there were sharks, some fish, crocodiles.

The complete disappearance of dinosaurs opened up new ecological niches that other creatures could occupy. Subsequently, the migration of mammalian animals to vacated sites led to their modern abundance on the planet.

New information about the past of the planet

Drilling the world's largest crater located in the area of the Yucatan peninsula and taking more and more samples will allow scientists to get more information about how the crater was formed and the consequences of the fall on the formation of new climatic conditions. Samples taken from the interior of the crater will allow specialists to understand what happened to the Earth after the strongest blow and how life was subsequently restored. It is interesting for scientists to understand how the restoration took place and who returned first, how quickly the evolutionary diversity of forms appeared.

Despite the fact that certain species and organisms died, other forms of life began to flourish doubly. According to scientists, such a picture of the disaster on the planet could be repeated throughout the history of the Earth many times. And every time everything died, and later the processes of recovery took place. It is likely that the course of history and development would be different if 65 million years ago an asteroid did not fall to the planet. Experts also do not exclude the possibility that life on the planet was born due to the fall of large asteroids.

Instead of an afterword

The fall of the asteroid caused the strongest hydrothermal activity of the Chicxulub Crater, which, most likely, lasted 100,000 years. It could allow hypermatophiles and thermophiles (these exotic unicellular organisms) to thrive in hot environments, settling inside the crater. This hypothesis of scientists, of course, needs verification. It is the drilling of rocks that can help shed light on many events. Therefore, before scientists there are still many questions on which it is necessary to receive answers, studying Chiclubul (crater).

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