How many billion years ago did the earth form in the oceans

How many years ago did the earth form?

According to geological research, the earth was formed about 4.6 billion years ago. At that time, the temperature of the earth was very high, and the environment on the ground was completely different from that of today: the sky was scorching with sunshine, lightning and thunder, volcanoes erupted on the ground, and lava flowed across the ground. Gases emitted from volcanoes, such as water vapor, hydrogen, ammonia, methane, carbon dioxide, hydrogen sulfide, etc., form the original atmosphere (there is no oxygen in the original atmosphere). About one billion years after the formation of the earth, primitive life gradually formed.

How many billion years ago did the earth form in the oceans

Scientists speculate that many simple organic substances were formed in the primitive atmosphere under the long-term effect of natural conditions such as high temperature, ultraviolet light and lightning. Later, the temperature of the earth gradually dropped, and the water vapor in the original atmosphere condensed into rain and fell to the ground. These organics entered lakes and rivers with the rain, and finally gathered in the original ocean.

The surface temperature of the original earth was higher than the boiling point of water; So water existed in the primitive atmosphere in the form of water vapor at that time. The surface is constantly radiating heat, and water vapor is cooled and condensed into water. Later, the temperature of the earth's interior gradually decreased, and the ground temperature finally dropped below the boiling point, so the heavy rain fell from the sky and fell to the lower part of the earth's surface, forming rivers, lakes and oceans.

When did the earth form

The Earth is an Earth like planet with the largest diameter, mass and density in the solar system, 150 million kilometers away from the sun. When did the Earth form? Here I have sorted out the formation time of the earth for your reference. I hope you can get something from your reading!

The formation time of the earth

The earth was born 4.6 billion years ago.

The birth of the universe 15 billion years ago laid the material foundation for the generation of the earth. Earth as a planet originated from the primitive solar nebula 4.6 billion years ago.

Since then, the earth system has changed from simple to complex, and the various components are both interrelated and mutually affected. The movement of the earth system and the changes in appearance, life phenomena and life activities brought about by the movement constitute the history of the earth.

Systematic scientific research on the origin and evolution of the earth began in the middle of the 18th century, and many theories have been put forward so far. It is generally believed that the Earth, as a planet, originated from the primitive solar nebula 4.6 billion years ago. Like other planets, the Earth has experienced some common physical evolution processes such as accretion and collision.

The material that formed the original Earth is mainly the original material of the nebula disk, which is mainly composed of hydrogen and helium, accounting for about 98% of the total mass. In addition, there are solid dust and materials thrown out during the early stage of solar contraction and evolution. During the formation of the Earth, due to the differentiation of materials, light materials are constantly separated from volatile materials such as hydrogen and helium, and brought to the outside of the solar system by the solar light pressure and the materials thrown out by the sun. Therefore, only heavy materials or soil materials are condensed to gradually form the original Earth and evolve into today's Earth. Like the Earth, Mercury, Venus and Mars may have similar formation patterns due to their close proximity to the sun, and they retain more heavy matter; However, Jupiter, Saturn and other exoplanets still retain more light matter because they are far away from the sun. Although there is still a lot of speculation about the way of forming the primitive earth, most researchers' views are consistent with Mr. Davidson's conclusion, that is, after the formation of the above nebula disk, due to the role of gravity and gravitational instability, the matter in the nebula disk, including dust layer, forms many protoasteroids or called planetesimals due to collision and accretion, and then gradually evolves, Gathered into planets, the earth was born in them. According to estimates, the time required for the formation of the Earth is about 10 million to 100 million years. Planets closer to the sun (Earth like planets) have a shorter formation time. Planets farther away from the sun have a longer formation time, even hundreds of millions of years.

The origin of the earth's land formation

With regard to the origin of continents, geological and geophysical physicist A. L. Du Toit put forward the model that there were two primitive continents on the earth in his book "Our Drifting Continent" in 1937. If this model holds, these two primitive continents are called Lanrasia and Gondwanaland respectively; In fact, this is just like what Weigner and others had advocated before, that is, the global continent is only combined into an ancient continent. Du Toit believed that the two original continents were originally formed near the poles of the earth, where the Laoya Ancient Land was in the north and the Gondwana Ancient Land was in the south. After their formation, they gradually broke and drifted to the position of today's continental block.

As early as the end of the 19th century, geologist E. Suess had recognized that the geological structures of the continents in the southern hemisphere of the earth were very similar, and merged them into a paleocontinent for research, and called it Gondwana, which originated from a standard stratigraphic area name (Gondwana) in eastern and central India. Gondwana includes South America, Africa, Madagascar, Arabian Peninsula, Indian Peninsula, Sri Lanka, Antarctica, Australia and New Zealand. They were all formed in the same geological age, and there are the same kind of plant fossils in the rock strata, which are called Gondwana rocks. The main evidence used by Du Toit to prove the existence and drift of Laoya and Gondwana is from geology, paleontology and paleoclimatology. According to the data accumulated over 30 years, the theory of Gondwana Ancient Land is basically correct.

Laoya Ancient Land is a combination of Europe, Asia and North America. Even now, these landmasses are not far apart. The Laoya Ancient Land has a very complex history of formation and evolution. It is mainly composed of several ancient landmasses, including the ancient North America landmass, the ancient Europe landmass, the ancient Siberian landmass and the ancient China landmass. In the Late Paleozoic (about 300 million years ago), these ancient landmasses gradually disturbed and collided, and gradually closed from the early and middle Carboniferous to the Permian (that is, 200 million to 270 million years ago). The data of paleogeology, paleoclimate and paleontology show that the Laoya Ancient Land was located in the middle and low latitudes during the Carboniferous Permian period. After the Mesozoic era (that is, in the recent 1-2 billion years), the Lauria continent gradually broke up, leading to the formation of the North Atlantic expansion. The research shows that the formation and distribution of new orogenic belts in the world are the result of the rupture and drift of the Laoya and Gondwana ancient continents. In this process, the laws of uneven westward movement and apolar movement of continental blocks are very obvious. On the whole, Laoya Ancient Land was once located in the middle and high latitudes of the Northern Hemisphere, and Gondwana Ancient Land was once located near the South Pole of the Southern Hemisphere; The two continents are separated by an area called the ancient Mediterranean (also known as the Tethys geosyncline).

Before Duttot (1937) put forward the theory of Laoya and Gondwana, A.L. Wegener put forward the theory that there was only one original continent on the earth as early as 1912, which was called United Ancient Land. Wegener believes that it was formed during the Carboniferous period (about 220 million to 270 million years ago). Wegener took Lianhe Ancient Land as his starting point to describe continental drift. However, according to people's current understanding, the United Ancient Land proposed by Wegener is by no means a primitive continent. Although a large number of people still agree with the idea of united ancient land, the restoration map of ancient land made by them is quite different from the restoration map proposed by Wegener, on the contrary, it is somewhat close to the distribution theory of two ancient lands proposed by Du Toit.

The continental drift and plate movement in the last 200 million years have been proved and widely recognized. However, some people speculate that the plate movement may have started as early as 3 billion years ago, and the speed of plate movement is different in different geological periods. The continents have repeatedly collided and merged, as well as repeatedly broken and separated. Multiple collisions of continental blocks formed fold mountains and connected them to form a new continent, while the expansion of the ocean floor formed a new ocean basin. Therefore, it is very difficult to accurately recover the so-called "pre drift" of the continent more than 200 million years ago. The earth has a history of 4.6 billion years, and the oldest rock on the earth is known to be 4.374 billion years old [4], and its distribution area is quite small. In this way, from 4.6 billion years to 3.7 billion years, about 900 million years interval completely missing geological data. In addition, the geological records on the earth 2.5 billion years ago are also very limited, which brings many difficulties to the study of the early history of the earth.

How many billion years ago did the earth form

The earth was formed 4.6 billion years ago. The formation of the original earth. Before the formation of the earth, many asteroids in the universe revolved around the sun. These planets collided with each other, forming the original earth. As the collision gradually decreased, the earth began to cool from outside to inside, producing a thin crust - the crust.

About 1.6 billion years ago, the Earth only had 9 hours every day and night, which was much faster than the current rotation, and about 800 days a year; By 600 million years ago, every day and night had been extended to 20 hours, and the year had been shortened to 440 days. The earth was gradually slowing down its rotation speed, probably due to the tidal gravity of the moon.

Internal structure of the earth:

Like other terrestrial planets, the earth's interior can be divided into several layers according to its chemical or physical (rheological) properties. However, the core and outer core of the Earth are obviously different, which is a feature that other terrestrial planets do not have. The outer layer of the earth is the crust composed of silicate minerals, and below it is the mantle composed of viscous solids.

The boundary between mantle and crust is Moho discontinuity. The thickness of the crust varies with the location, from 6 km under the sea to 30 to 50 km on the land. The cold and hard upper layer of the crust and mantle is called the lithosphere, and the plates are also formed in this area. Below the lithosphere is the asthenosphere with low viscosity, and the lithosphere slides just above the asthenosphere.

Significant changes in the crystalline structure of the mantle occur between 410 and 660 kilometers below the surface, which is a transitional zone separating the upper mantle and the lower mantle. Below the mantle, there is the core mantle boundary (Gutenberg discontinuity) separating the mantle and core, and below it is the liquid outer core with very low viscosity, and the innermost is the solid inner core.

The angular velocity of the inland core rotation may be faster than that of other parts of the earth, about 0.1 – 0.5 ° ahead each year. The inland core has a radius of 1220km, about 1/5 of the earth's radius.

The earth was born hundreds of millions of years ago

According to the decay rate of radioactive materials on the earth, we know that our earth has existed for 4.6 billion years, that is, our earth was born 4.6 billion years ago.

In 1896, the natural radioactive element uranium was discovered in Becquerel, France. In 1905, it was found that the rocks had radioactive characteristics. Later, through further research, it was found that the specific age of rocks can be determined according to the transformation rate of radioactive elements in rocks. For example, the actual age of rock formation can be calculated by using the uranium lead method. Because one gram of uranium (U235) in a year, there will always be 1/7.4 billion grams of fission into lead and helium. As long as we conduct rock sampling according to certain requirements, and use special instruments to measure the ratio of radioactive element uranium (U235) and lead (Pb237) in rocks, we can calculate the age of rocks. This method is called isotopic dating. Isotopic age is also called absolute age. In addition, Rb Sr method, K Ar method and C14 method can also be used to measure rock age. In comparison, the uranium lead method is more ideal for measuring extremely ancient rocks. According to the calculation of ancient rocks in the original crust by the above method, the ancient rocks on the earth are generally not less than 3.6 billion to 3.7 billion years old. Up to 4 billion years.

In addition, because the age of the Earth at the time of its formation is similar to that of the solar system, scientists can calculate the age of the Earth at the time of its formation, which is about 4.6 billion years, by measuring some meteorites falling on the Earth and lunar rocks (soil) collected from the moon and combining the ages of the oldest rocks on the Earth. For example, the age of Jilin meteorite measured by Rb Sr method is 4.7 billion years. The materials that make up the Jilin meteorite were separated from the primitive nebula of the sun 4.7 billion years ago, so they are a little earlier than the age when the earth was formed. At present, it is generally limited to 4.6 billion years. The period since the formation of the ancient crust in 4.6 billion years is the geological time of the earth, also known as the period of the paleogeographic circle; The period before 4.6 billion is called the "astronomical period", also known as the "pre geological period".

How many billion years ago was the earth born

The earth was born 4.6 billion years ago. The birth of the universe 15 billion years ago laid the material foundation for the generation of the earth. Earth as a planet originated from the primitive solar nebula 4.6 billion years ago. Since then, the Earth system has changed from simple to complex, and the evolution of each component is both interrelated and interactive. The movement of the earth system and the geomorphic changes, life phenomena and life activities it brings together constitute the history of the earth.

The material that formed the original Earth is mainly the original material of the nebula disk, which is mainly composed of hydrogen and helium, accounting for about 98% of the total mass. In addition, there are solid dust and materials thrown out during the early stage of solar contraction and evolution. During the formation of the Earth, due to the differentiation of substances, light substances were continuously separated with volatile substances such as hydrogen and helium.

Chemical changes in the early stage of earth formation.

As for whether the original earth was hot or cold, scientists have different opinions. Based on the ancient theory of the origin of the earth, most people believed that the earth was originally a molten body. After several billion years of geological evolution, the earth still retains its heat. The results of modern research tend to the theory of the origin of the earth's low temperature.

Whether the early state of the earth was high temperature or low temperature is still controversial. However, whether it is the origin of high temperature or low temperature, the earth has generally experienced a stage from heat to cold. Because there are heat sources inside the earth, the cooling process is extremely slow, and the earth is still in the process of cooling.

The earth was formed hundreds of millions of years ago

4.6 billion years ago

Two research teams from Germany and the United States have studied the latest discovery that when the Earth and Mars were born

20 million years earlier than people thought

Scientists generally believe that the solar system was born in a huge supernova explosion 4.6 billion years ago

The explosive shock wave condenses the residual gas into clumps, forming the sun, planets

Satellites, asteroids and comets. But the time and speed of their birth are difficult to estimate

Count

In this study, the computer simulation of the evolution of the solar system shows that the earth's gold

The core of the genus may be formed between 20 million and 30 million years after the supernova explosion, and

Previous geological evidence suggests that it was formed 50 million years after the eruption

Scientists point out that 20 million years is just

A short time; But in the early years of the earth, the difference of 20 million years means that

Many things will be different

Two groups of researchers from Munster University in Germany and Harvard University in the United States are working in the newly published

The Chinese journal Nature reported that they had studied from Mars and the free sky

And compared with the earth rocks

Tungsten 128 is the content ratio of the two elements

The core of Venus and Mercury, the earth like planets, was less than 30 million after the explosion

The formation of the core of Mars may have taken only 130 million years in

We can better understand the early stage of the Earth's birth, which may also help explain the moon's

Origin

Hafnium 128 is a radioactive element with a half-life of 9 million years, and the decay product is tungsten

128. Because it is easy to combine with metals, all tungsten entered it in the early stage of the earth's formation

Therefore, the existing tungsten 128 in the mantle rock must come from the decay of hafnium 128

The ratio of these two elements can be used as a radioactive "clock" to determine the

According to the latest scientists' estimate, the formation of the earth is about 4.57 billion

Ten thousand years ago