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  1. Earth's history with time-spans of the eons to scale. The history of Earth concerns the development of planet Earth from its formation to the present day. Nearly all branches of natural science have contributed to understanding of the main events of Earth's past, characterized by constant geological change and biological evolution.

  2. 30 de abr. de 2024 · Learn about Earth, the planet we live on, its structure, features, and history. Explore maps, photos, and articles on Earth's interior, exterior, revolution, rotation, and more.

    • Origin of The Universe
    • Hadean Eon
    • Archean Eon
    • Proterozoic Eon
    • Phanerozoic EON: Paleozoic Era
    • Phanerozoic EON: Mesozoic Era
    • Phanerozoic EON: Cenozoic Era
    • Summary
    • GeneratedCaptionsTabForHeroSec

    The universe appears to have an infinite number of galaxies and solar systems and our solar system occupies a small section of this vast entirety. The origins of the universe and solar system set the context for conceptualizing the Earth’s origin and early history.

    Geoscientists use the geological time scale to assign relative age names to events and rocks, separating major events in Earth’s history based on significant changes as recorded in rocks and fossils. This section summarizes the most notable events of each major time interval. For a breakdown on how these time intervals are chosen and organized, see...

    Late Heavy Bombardment

    Objects were chaotically flying around at the start of the solar system, building the planets and moons. There is evidence that after the planets formed, about 4.1–3.8 billion years ago, a second large spike of asteroid and comet impacted the Earth and Moon in an event called late heavy bombardment. Meteorites and comets in stable or semi-stable orbits became unstable and started impacting objects throughout the solar system. In addition, this event is called the lunar cataclysm because most...

    Origin of the Continents

    The first solid evidence of modern plate tectonics is found at the end of the Archean, indicating at least some continental lithosphere must have been in place. This evidence does not necessarily mark the starting point of plate tectonics; remnants of earlier tectonic activity could have been erased by the rock cycle. The stable interiors of the current continents are called cratons and were mostly formed in the Archean Eon. A craton has two main parts: the shield, which is crystalline baseme...

    First Life on Earth

    Although the origin of life on Earth is unknown, hypotheses include a chemical origin in the early atmosphere and ocean, deep-sea hydrothermal vents, and delivery to Earth by comets or other objects. One hypothesis is that life arose from the chemical environment of the Earth’s early atmosphere and oceans, which was very different than today. The oxygen-free atmosphere produced a reducing environment with abundant methane, carbon dioxide, sulfur, and nitrogen compounds. This is what the atmos...

    An oxygenated world also changed the chemistry of the planet in significant ways. For example, iron remained in solution in the non-oxygenated environment of the earlier Archean Eon. In chemistry, this is known as a reducing environment. Once the environment was oxygenated, iron combined with free oxygen to form solid precipitates of iron oxide, su...

    Life in the early Paleozoic Era was dominated by marine organisms but by the middle of the era plants and animals evolved to live and reproduce on land. Fish evolved jaws and fins evolved into jointed limbs. The development of lungs allowed animals to emerge from the sea and become the first air-breathing tetrapods (four-legged animals) such as amp...

    8.7.1 Mesozoic Tectonics and Paleogeography

    This age pattern shows how the Atlantic Ocean opened as the young Mid-Atlantic Ridge began to create the seafloor. This means the Atlantic ocean started opening and was first formed here. The southern Atlantic opened next, with South America separating from central and southern Africa. Last (happening after the Mesozoic ended) was the northernmost Atlantic, with Greenland and Scandinavia parting ways. The breaking points of each rifted plate margin eventually turned into the passive plate bou...

    8.8.1 Cenozoic Tectonics and Paleogeography

    Animation of the last 38 million years of movement in western North America. Note, that after the ridge is subducted, convergent turns to transform (with divergent inland).

    The changes that have occurred since the inception of Earth are vast and significant. From the oxygenation of the atmosphere, the progression of life forms, the assembly and deconstruction of several supercontinents, to the extinction of more life forms than exist today, having a general understanding of these changes can put present change into a ...

    Learn about the origins of the universe, the solar system, and Earth in the context of big-bang theory and nebular theory. Explore the geological clock and the major tectonic and biologic events that shaped Earth's history.

  3. 19 de out. de 2023 · Learn how Earth was created from a cloud of dust and gas, and how it evolved into a habitable planet with oceans, atmosphere, and life. Explore the stages of Earth's development, the role of asteroids, and the evidence of early life.

  4. 5 de abr. de 2024 · geologic history of Earth, evolution of the continents, oceans, atmosphere, and biosphere. The layers of rock at Earths surface contain evidence of the evolutionary processes undergone by these components of the terrestrial environment during the times at which each layer was formed.

  5. Earth formed about 4.54 billion years ago by accretion from the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun, which also created the rest of the Solar System . Initially, Earth was molten due to extreme volcanism and frequent collisions with other bodies.

  6. 5 de abr. de 2024 · Learn about the geologic time scale, which subdivides Earth's history into eons, eras, periods, epochs, and ages based on rock strata and fossil records. Explore the timeline of Earth's history, the diversity of marine families, and the mass-extinction events.

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