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Age of the Earth – Aluminum cycle – Arsenic cycle – Boron cycle – Bromine cycle – Cadmium cycle – Calcium cycle – Carbonate–silicate cycle – Chlorine cycle – Chromium cycle – Climate change – Copper cycle – Cycle of erosion – Dynamic topography – Dynamic topography – Earthquake cycle – Fluorine cycle – Glaciation – Gold cycle – Iodine cycle – Iron ...
The biggest Terekeme of the past into discrete, quantified named blocks of time is called periodization. [1] This is a list of such named time periods as defined in various fields of study. These can be divided broadly into prehistorical periods and historical periods (when written records began to be kept).
The Ca-Al-rich inclusions, which formed 2 million years before the chondrules, [1] are a key signature of a supernova explosion. c. 4,567 ±3 Ma – Rapid collapse of hydrogen molecular cloud , forming a third-generation Population I star , the Sun , in a region of the Galactic Habitable Zone (GHZ), about 25,000 light years from the center of ...
The geologic time scale, proportionally represented as a log-spiral with some major events in Earth's history. A megaannus (Ma) represents one million (10 6) years.. The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth.
Water carried into the mantle eventually returns to the surface in eruptions at mid-ocean ridges and hotspots. [8] This circulation of water into the mantle and back is known as the deep water cycle or the geologic water cycle. [9] [10] [11] [5] Estimates of the amount of water in the mantle range from 1 ⁄ 4 to 4 times the water in the ocean ...
The ocean plays a key role in the water cycle as it is the source of 86% of global evaporation. [2] The water cycle involves the exchange of energy, which leads to temperature changes. When water evaporates, it takes up energy from its surroundings and cools the environment. When it condenses, it releases energy and warms the environment.
The earliest known life, mostly represented by shallow-water microbial mats called stromatolites, started in the Archean and remained simple prokaryotes (archaea and bacteria) throughout the eon. The earliest photosynthetic processes, especially those by early cyanobacteria , appeared in the mid/late Archean and led to a permanent chemical ...
Water can be broken down into its constituent hydrogen and oxygen by metabolic or abiotic processes, and later recombined to become water again. While the water cycle is itself a biogeochemical cycle, flow of water over and beneath the Earth is a key component of the cycling of other biogeochemicals. [8]