Archaean: 3.8 billion to 2.6 billion years ago, that is, 65.438+0.2 billion years, was the initial period after the formation of the earth. Copper mountains and deserts have formed everywhere on the surface. From a biological point of view, this is the initial stage of the emergence of primitive life and biological evolution. There were few prokaryotes at that time, and only a few fossil records were left. From the abiotic point of view, Archean was a period of thin crust, steep geothermal gradient, intense and frequent volcanic-magmatic activities, widespread deformation and metamorphism of rock strata, lack of free oxygen in the atmosphere and hydrosphere, and formation of a series of special sediments. It is also a period of formation and growth of silicon-aluminum crusts and an important metallogenic period.
Proterozoic: from 2.6 billion years ago to 570 million years ago, during this geological historical period, prokaryotes evolved into eukaryotes, forming the era of bacteria and algae in geological period. Micro-ancient plant fossils, macro-algae fossils and stromatolites were found in the paleostrata of this period. In China alone, paleontologists have discovered more than 80 genera and nearly 200 species of microphyte fossils in different periods of Proterozoic. Proterozoic life has further flourished and the earth is no longer barren. Initially, some relatively stable large-scale and thick continental plates appeared on the surface. Therefore, in terms of lithospheric structure, Proterozoic is more stable than Archean. The atmosphere in the late Early Proterozoic already contained free oxygen. With the increasing prosperity of plants and the strengthening of photosynthesis, the oxygen content in the atmosphere increased continuously. Algae flourished in the middle and late Proterozoic.
Sinian: It can be divided into glacial stage, extensional stage, narrow-band stage, extensional stage, caprock stage, consolidation stage, orogenic stage, stratigraphic stage and iron-forming stage. About 850-570 million years ago, there was clear biological evidence in the Sinian. There were low and small hard-shelled species and a large number of naked advanced animals in the animal kingdom, the latter being the Ediacaran fauna found in Australia. In terms of plants, higher algae (such as red algae, brown algae, etc. ) further prosperity, macro algae also developed rapidly. At this time, the earth has completely changed its lifeless appearance, and the Ediacaran fauna is mainly composed of creatures like jellyfish, worms and sea gills.
CAMBRIAN: CAMBRIAN can be divided into early CAMBRIAN, middle CAMBRIAN and Furong period. Fauna is characterized by a large number of marine invertebrates with hard shells and various categories, which is a great development in the history of biology. Among them, trilobites are the most common, which is an important basis for dividing CAMBRIAN. Trilobites were the overlord at that time.
Ordovician: It started from 488 geological units (480 million years ago) to 444 geological units (440 million years ago) and lasted for 42 million years. It can be divided into three periods-early Ordovician (early Ordovician, 485-470 million years ago), middle Ordovician (middle Ordovician, 470-458 million years ago) and late Ordovician (late Ordovician, 458-443 million years ago). Ordovician is one of the most extensive periods of Shanghai invasion in history, and marine strata are widely distributed in many parts of the world. In the platform area inside the plate, seawater is widely distributed, showing the extensive development of carbonate rocks in coastal shallow sea. In the active geosyncline area on the plate edge, it is a deep-water environment, forming thick shallow and deep-sea clastic deposits and volcanic eruption deposits. There was a large-scale ice age at the end of Ordovician, which was distributed in Africa (especially in North Africa), Argentina and Bolivia in South America, Spain and southern France in Europe.
Silurian: During the graptolite period, terrestrial plants and jaws appeared, which was the last period of Early Paleozoic and the third period of Paleozoic. It started about 440 million years ago and ended 4. 1 100 million years ago. Silurian was once called Godland because it developed well on Godland Island in the Baltic Sea. Silurian can be divided into early, middle and late ages. The third division of Silurian is remarkable. Generally speaking, transgression generally formed in the Early Silurian, peaked in the Middle Silurian, and regressed and uplifted in different degrees in the Late Silurian, showing a huge transgression cycle. In the late Silurian, the strong crustal movement, the closure of the ancient Atlantic Ocean and the collision of some plates led to the rise of some geosynclines, the great changes in paleogeography, the remarkable expansion of the continental area and the great evolution of the biological world, all of which marked a turning point in the historical development of the crust.
Devonian: Devonian refers to the Middle Paleozoic. It can be divided into three periods-Devonian, Middle Devonian and Late Devonian. The geological age, the fourth stage of Paleozoic, began about 405 million years ago and ended about 350 million years ago, lasting about 50 million years. Devonian is divided into early, middle and late stages, and the strata are also divided into lower, middle and upper stages. Early gymnosperms flourished, and ferns and primitive gymnosperms appeared after the middle period. In addition to corals, brachiopods and laminaria (Gastropoda, Hydra), invertebrates, as well as primitive Shiju (Cephalopoda, a subclass of molluscs) and insects continue to flourish. Fish in vertebrates (including soft-shelled turtle, shield fish, total fin fish, etc.). ) With unprecedented development, Devonian is also called "Fish Age". In the late stage, crustaceans tended to be extinct, and primitive amphibians (Milton and Cephalotaxus) began to appear. Since Devonian, Hercynian movement has started on the earth. Therefore, during the Devonian period, many areas rose out of the sea and became land, and the paleogeographic features changed greatly in the early Paleozoic. In Devonian, ferns flourished and insects and amphibians increased. Between Devonian and Carboniferous, there was a great extinction-super mantle plume. In this mass extinction, 75% of the species became extinct. It is the second largest extinction species, second only to the first Permian extinction-Siberian dark rock event. The main extinct animals are shield fish and attenborough female fish. Vertebrates entered a period of rapid development, the number and species of fish-like animals increased, and the modern fish-bony fish began to develop. Devonian is usually called "the age of fish".
Carboniferous: About 286 million to 360 million years ago, it can be divided into two periods: Early Carboniferous (also called Mississippian, 320 million to 360 million years ago) and Post Carboniferous (also called Pennsylvanian, 286 million to 320 million years ago). Carboniferous is the fifth period of Paleozoic, which started from about 355 million years ago to 295 million years ago and lasted for 65 million years. In Carboniferous, the land area was increasing, and terrestrial organisms were unprecedentedly developed. At that time, the climate was warm and humid, and swamps were everywhere. A large area of forest has appeared on the mainland, which has created favorable conditions for the formation of coal. The large-scale glacial activity in Gondwana continent lasted for 50 million years from the end of Carboniferous to the beginning of Permian, and it belongs to the polar continental ice sheet type.
Permian: It is the last period of Paleozoic and an important coal-forming period. The Permian started about 299 million years ago and continued to 250 million years ago, and * * * experienced 45 million years. The Permian crustal movement was active, and the relative movement between ancient plates intensified. Many geosynclines around the world are closed, and wrinkled mountain systems are formed one after another, and ancient plates are gradually spliced to form a United ancient continent (Pangu land). The further expansion of land area, the narrowing of ocean scope and the change of natural geographical environment have promoted the important evolution of the biological world and heralded the arrival of a new period in the history of biological development. Early plants were mainly true ferns and seed ferns. There are great changes in the later period, such as LEPIDOPTERA, reed, seed fern, Kodak tree and so on. Tending to decline and extinction, it was replaced by drought-tolerant gymnosperms, conifers and cypresses, and Cycas began to develop. Brachiopods continue to flourish, and long-bodied shellfish are dominant; Molluscs are also an important part, and ammonites have obvious differentiation; Bryozoa gradually declined; Trilobites tend to be extinct; Insects began to develop rapidly. Reptiles proliferated for the first time, and Ceratosaurus, Panlong and theropoda existed. At the end of Permian, the Permian-Triassic extinction occurred, and 90% to 95% of marine life became extinct. The detailed reason is not clear.
Triassic: It is the geological age from 250 million BC to 200 million BC. It is located between Permian and Jurassic and is the first period of Mesozoic. The beginning and end of Triassic was marked by an extinction event. Although the rock marks in this period are very obvious and clear, the exact time of its beginning and end can not be determined as accurately as other ancient geological ages. The error is plus or minus millions of years. During the Triassic, most of the continents on the earth formed a huge continent: Pan-continent. Because the Triassic began with an extinction event, its creatures were very differentiated from the beginning. Six-release Corallinae appeared at this time, and the earliest angiosperms and the earliest flying vertebrates (pterosaurs) may also appear at this time. The earliest tortoise in the world, the protognathus, also appeared in the late Triassic. The first ichthyosaurs appeared. Dinosaurs appeared.
Jurassic: It is a geological age between Triassic and Cretaceous, about 654.38+099.6 million years BC (with an error of 600,000 years) to 654.38+045.5 million years BC (with an error of 4 million years). Jurassic is the second period of Mesozoic, which began with the Triassic-Jurassic extinction event. Although the rock marks in this period are very obvious and clear, the exact time of its beginning and end, like other ancient geological ages, cannot be determined very accurately. There have been some important events in the history of biological development, which have attracted people's attention, such as dinosaurs becoming the rulers of the land, pterosaurs and birds appearing, and mammals beginning to develop. The Jurassic gymnosperms reached their peak. The bivalves, gastropods, arachnids, ostracods and insects of freshwater invertebrates have developed rapidly. Marine ammonites, bivalves and arrow stones are still important members, and the six-coral has not changed much from Triassic to Jurassic. Echinoderm sea urchin has occupied an important position since Jurassic.
Cretaceous: The last period of Mesozoic in geological age, starting from 654.38+45 million years ago and ending at 66 million years ago, lasting 79 million years. This is the longest stage of Phanerozoic. During the Cretaceous period, the continent was separated by the ocean, and the earth became warm and dry. In the biggest dinosaur period, many new dinosaur species began to appear, dinosaurs still ruled the landing land, pterosaurs glided in the sky, and huge marine reptiles ruled the shallow sea. The earliest snakes, moths, bees and many new small mammals also appeared. Angiosperms also appeared in this period.
Cenozoic: It is the latest geological age in the history of the earth. With the extinction of dinosaurs, Mesozoic ended and Cenozoic began. The Cenozoic is divided into three periods: Paleogene, Neogene and Quaternary. The total includes seven eras: Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene and Holocene. The strata formed in this period are called Cenozoic. The Cenozoic era is characterized by the high prosperity of mammals and angiosperms. Because the biological world gradually presents a modern look, it is named the Cenozoic era, that is, the era of modern biology. The Paleogene climate was colder than before, and small ice sheets appeared in the Antarctic continent in the late Eocene and Oligocene. The ice sheet formed there in the middle Miocene is equivalent to 2/3 of that in modern times. Greenland ice sheet appeared in the northern hemisphere in the early Pleistocene, and there were many ice ages in the following 2 million years. Glaciers have been found on several continents.
Anthropocene: it is defined as the influence of human beings on the earth, that is, human beings have become geological forces affecting the global topography and the evolution of the earth.
Degeneration: the death of mankind and the death of the universe. In the early stage of degradation, the sun became a red giant and swallowed the earth. In the middle stage of degeneration, the stars are extinguished one after another, and no new stars are formed. The sun is just a white dwarf, becoming the only light in the universe. In the late stage of degradation, the universe died and the sun changed from a white dwarf to a black dwarf. The death of the universe is not explosion or collapse, but endless cold and darkness.