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. Chiksulub is a crater formed after a meteorite fall 65 million years ago. Its appearance on Earth has led to serious consequences that have 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. The Chiksulub 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.
Discovery story
The discovery of the crater was random. Since it is of enormous size, we did not even know about its existence. Scientists discovered it quite by accident in 1978 during geophysical exploration of the Gulf of Mexico. The research expedition was organized by PEMEX (full name "Mexican Petroleum"). She faced a difficult task - to find oil fields at 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 water. Thanks to the gravitational map, scientists have found a continuation of this arc on the Yucatan Peninsula (Mexico) in the vicinity of the village of Chicxulub.
The name of the village is translated from the language of the Mayan Indians as "demon ticks." 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 many assumptions.
Scientific justification of the hypothesis
Closing together, the arcs found form a circle whose diameter is 180 kilometers. One of the researchers, named Penfield, immediately suggested that it was an impact crater that appeared as a result of a meteorite fall.
His theory turned out to be true, which was confirmed by some facts. A gravitational anomaly was found inside the crater . In addition, scientists discovered samples of “shock quartz” having a squeezed molecular structure, as well as glassy tektites. Such substances can be formed only at extreme values of pressure and temperature. The fact that Chikskulub 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.
The hypothesis was scientifically confirmed by a professor at the University of Calgary, Hildebrant, in 1980 thanks to a study of the chemical composition of the rocks of the area and detailed satellite imagery of the peninsula.
Consequences of a meteorite fall
It is believed that Chiksulub is a crater formed when a meteorite falls, whose diameter is at least ten kilometers. Scientists' calculations show that the meteorite was moving at a slight angle from the southeast. Its speed was 30 kilometers per second.
The fall of a huge cosmic body on Earth occurred approximately 65 million years ago. Scientists suggest that this event occurred just at the turn of the Paleogon and Cretaceous. The consequences of the impact were catastrophic and had a tremendous impact on the further development of life on Earth. As a result of a collision of a meteorite with the earth's surface, the largest crater on Earth formed.
According to scientists, the impact power exceeded several million times the power of an atomic bomb dropped on Hiroshima. As a result of the strike, 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, the tsunami started from a powerful blow. Presumably, the height of their waves was 50-100 meters. Waves went to the continents, destroying everything in its path.
Global cooling on the planet
The shock wave circled the entire Earth several times. With a high temperature, it caused severe forest fires. Volcanism and other tectonic processes have intensified in different regions of the planet. Numerous volcanic eruptions and the burning of large forests have led to the fact that a huge amount of gases, dust, ash and soot got into the atmosphere. It is difficult to imagine this, 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.
Such climate changes, along with other severe consequences of the impact, had a devastating effect on the living world of the planet. The 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 vegetation cover of the Earth led to the death of animals that lacked food. It was these events that led to the complete extinction of the dinosaurs.
Extinction at the boundary of the Cretaceous and Paleogene period
The fall of a meteorite is currently considered the most convincing cause of the mass death of all living things in the Cretaceous-Paleogene period. The version of the extinction of living creatures took place even before the Chiksulub (crater) was discovered. And one could only guess about the reasons that caused the cooling of the climate.
Scientists have discovered a high content of iridium (a very rare element) in sediments, whose age is approximately 65 million years. An interesting fact is that a high concentration of the element was found not only on the Yucatan, but also in other places of the planet. Therefore, experts say that, most likely, there was a meteor shower.
On the border of the Paleogene and Cretaceous, all dinosaurs, flying dinosaurs, marine reptiles that reigned for a long time in this period became extinct. Absolutely all ecosystems were destroyed. In the absence of large lizards, 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. Available calculations suggest that large cosmic bodies fall on Earth once every hundred million years. And this roughly corresponds to the lengths of time between mass extinctions.
What happened after the meteorite fell?
What happened on Earth after a meteorite? According to paleontologist Daniel Dourd (Colorado Research Institute), in a matter of minutes and hours, the lush and flourishing world of the planet has turned into a desolate land. Thousands of kilometers from the place where the meteorite fell, everything was completely destroyed. The blow 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 a crater. But after it was found, it became necessary to study it, since scientists have accumulated many hypotheses that need verification, questions and assumptions. If you look at the Yucatan Peninsula on a map, it is difficult to imagine the real dimensions of the crater on the ground. Its northern part is located far from the coast and is covered with 600 meters of oceanic deposits.
In 2016, scientists began drilling in the offshore area 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.
Post-disaster events
The fall of the asteroid has evaporated a huge part of the earth's crust. Debris soared into the sky above the crash site, fires and volcanic eruptions erupted on Earth. It was soot and dust that closed the sunshine and plunged the planet into a very long period of winter darkness.
Over 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 for paleontologists is evidence of a turning point in the history of the Earth.
In the region of North America, before the meteorite hit, lush forests flourished 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 on the Seymour Islands.
Scientists studied the consequences of a meteorite impact on the earth, analyzing the Cretaceous-Paleogene layer found in more than 300 places around the world. This gave reason to say that near the epicenter of events all living things died. The opposite part of the planet suffered from earthquakes, tsunamis, lack of light and other consequences of the disaster.
Those living things that did not die immediately died from a lack of water and food destroyed by acid rain. The death of the vegetation led to the death of herbivores, from which the carnivores suffered, left without food. All 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. It was they who had a chance to survive in those conditions. Since they eat less, they reproduce faster, and they adapt more easily.
Fossils say that in Europe and North America there was a more favorable situation after the disaster than in other places. Mass extinction is a dual process. If on the one hand something died, on the other hand something must arise. So scientists say.
Earth restoration took a very long time. Hundreds and even thousands of years passed before ecosystems were restored. Presumably, it took the oceans three million years to restore normal organisms.
After severe fires, ferns settled in the ground, quickly populating the burnt regions. Those ecosystems that escaped fire were inhabited by mosses and algae. The areas least affected by the destruction became places where some species of living things could survive. Later they settled all over the planet. So, for example, sharks, some fish, and crocodiles survived in the oceans.
The complete extinction of the dinosaurs has opened up new ecological niches that other creatures could occupy. Subsequently, the migration of mammalian animals to the vacated places 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 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 inside of the crater will allow specialists to understand what happened to the Earth after a strong blow 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 variety 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 disaster on the planet could be repeated many times in the entire history of the Earth. And every time all living things died, and later on, restoration processes took place. It is likely that the course of history and development would be different if 65 million years ago the asteroid did not fall on the planet. Experts also do not exclude the possibility that life on the planet originated 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 enable hypermatophiles and thermophiles (these are exotic unicellular organisms) to thrive in hot environments, settling inside the crater. This hypothesis of scientists, of course, needs to be verified. 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 Chiksulub (crater).