If humans suddenly disappear, how long will it take for the earth to completely erase the traces of human civilization?

It is generally believed that the earth was born 4.6 billion years ago, life on earth originated 3.5 billion years ago, and humans appeared two or three million years ago.

Human beings created civilization, which started with the invention of writing. The earliest time is only seven or eight thousand years. These few thousand years only account for a few percent of human history. If the time is extended to the beginning of the birth of the earth, then the history of human civilization is not worth mentioning at all in the face of 4.6 billion years.

However, in this short period of seven or eight thousand years, mankind has created a splendid material civilization and spiritual civilization. Humans built the Great Wall, Qin Terracotta Warriors, Pyramids and Hanging Gardens of Babylon. Humans have established the "four ancient civilizations" of ancient China, ancient India, ancient Egypt and ancient Babylon. Humans have created modern science and diverse arts, leaving countless traces of human civilization on the earth.

Have we ever thought about how long it will take for the earth to completely erase the traces left by human civilization if human beings all over the world suddenly disappear from the earth one day?

Many people may first think of the Chernobyl nuclear accident in 1986. After the accident that year, in just a few dozen hours, all the local residents were evacuated urgently, and the whole city fell into a dead silence, as if it had become a ghost town overnight. Decades later, Chernobyl is overgrown with grass and wild animals of all kinds have taken over the city, as if human civilization had never set foot here.

Is this really true? Can human civilization really be wiped out in a few decades?

In the first few hours before human beings disappeared, the whole world basically did not change. The traffic lights on the road would still be on, but there were no pedestrians and vehicles. The elevator in the office building was still running normally, but no one pressed the button. button; shows and commercials are still on TV, but there are no viewers. Even animals don't sense the disappearance of humans.

In a few hours, all the thermal generators around the world will stop working because they run out of fuel.

After 48 hours, all the hydro, wind and solar generators around the world will stop working due to lack of human scheduling, management and maintenance. When night falls, the whole earth will be plunged into darkness. However, when the weather is good, the starry sky will become especially beautiful.

A week later, pets such as kittens and puppies raised at home, chickens, ducks, cows, sheep and other livestock raised on farms will all starve and die of thirst, and only a few can escape to the wild to survive. Various pipe network systems carefully designed and constructed by humans, including urban drainage systems and groundwater systems, will gradually flood the underground space.

A month later, due to the lack of manual maintenance, the cooling water will evaporate completely, and all nuclear power plants built by humans will explode due to excessive temperature, which will inevitably lead to nuclear leakage accidents. Nuclear radiation will cause the death or disease of animals and plants within a radius of tens of kilometers. However, without humans, such a nuclear accident would not cause much harm to nature. Perhaps in just a few years, the nuclear leaked area will be back to life again.

Due to the paralysis of electricity, human embryonic cells, sperm cells, egg cells and hundreds of thousands of plant seeds will be thawed and decayed, and the possibility of rebirth will be completely lost.

In three months, without the calibration and maintenance of the ground crew, the International Space Station and thousands of artificial satellites will fall into the atmosphere, as if a tragic meteor shower bid farewell to mankind.

A year later, all the cities are overgrown with weeds, and some kittens and puppies who survived are wandering the streets in groups of three or five, looking for food left by humans.

Ten years later, all kinds of buildings and roads built by humans have become dilapidated, all kinds of weeds and trees have grown wildly, and the urban green area has inadvertently soared.

A hundred years later, most of the wooden buildings built by humans will collapse and decay, and the high-rise buildings with steel structures in cities will also begin to become precarious. The optical discs and film films that humans use to store civilization information have come to an end under the influence of environmental changes such as temperature and humidity. All kinds of paper books in the library will be destroyed by the erosion of fungi.

Two hundred years from now, human-built skyscrapers will collapse, even the Eiffel Tower.

Three hundred years later, all kinds of dams and bridges built by human beings will collapse, the waves will sweep in, there will be unbridled floods everywhere, and marine life will usher in a revival.

A thousand years later, the whole world will return to dust and earth to earth, all kinds of reinforced concrete buildings built by human beings will no longer exist, and the naked eye can no longer distinguish between cities and natural areas. The earth is full of plants and animals are running everywhere. Most of the marine debris left by humans is degraded into fine particles by nature.

Ten thousand years from now, if you still want to see traces of human civilization, you can only hope for the Great Wall and the Pyramids. These stone buildings may not have been weathered.

After 50,000 years, the glass and special plastics made by humans will also disappear without a trace, and there will be no traces.

After 100,000 years, traces of human activity will only be found by digging underground like archaeologists.

Ten million years later, if you want to explore the traces left by human civilization, you can only find clues in gold products, diamond products and graphite products.

After 100 million years, the earth will no longer be what it is now. Plate movement will crush all the imprints of civilization left by humans in caves and underground.

In other words, it will take about 100 million years for the earth to completely erase the traces left by human civilization.

However, the earth was only 4.7 billion years old by then, and it took only one forty-seventh of its lifespan to annihilate the only civilization in the entire solar system and even the entire universe. Just imagine, if a new civilization is born on the earth every 100 million years, then in the past billions of years and hundreds of millions of years in the future, N different civilizations that do not know each other may be born on the earth. Is this also true? Can it be understood as a special form of reincarnation?