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The first eon in Earth's history, the Hadean, begins with the Earth's formation and is followed by the Archean eon at 3.8 Ga. [2]: 145 The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to about 4.4 Ga, [34] [35] [36] soon after the formation of the Earth's crust and the Earth
Earth is the only place in the universe known to harbor life, where it exists in multiple environments. [8] [9] The origin of life on Earth was at least 3.5 billion years ago, possibly as early as 3.8-4.1 billion years ago. [2] [3] [4] Since its emergence, life has persisted in several geological environments.
Khnum (right) is a creator god who forms humans and gods out of clay. Here Isis (left) gives life. The creation of life from clay can be seen as a miraculous birth theme that appears throughout world religions and mythologies. It can also be seen as one of gods who craft humans out of earthly materials. As such, this class of story falls within ...
A Quaternary clay deposit in Estonia, laid down about 400,000 years ago. Clay is a type of fine-grained natural soil material containing clay minerals [ 1] (hydrous aluminium phyllosilicates, e.g. kaolinite, Al 2 Si 2 O 5 ( OH) 4 ). Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities ...
Earth's crust is its thick outer shell of rock, referring to less than one percent of the planet's radius and volume. It is the top component of the lithosphere, a solidified division of Earth's layers that includes the crust and the upper part of the mantle. [ 1] The lithosphere is broken into tectonic plates whose motion allows heat to escape ...
Soil. Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from soil by restricting the former term specifically to displaced soil.
Other earth materials include soil blocks typically stabilized with a cement additive and produced with forms or compression. Rammed Earth consists of walls made from moist, sandy soil, or stabilized soil, which is tamped into form work. Walls are a minimum of 12″ thick. Soils should contain about 30% clay and 70% sand. [4]
Earthen hut with thatched roof in Toteil, near Kassala, Sudan. An earth structure is a building or other structure made largely from soil. Since soil is a widely available material, it has been used in construction since prehistory. It may be combined with other materials, compressed and/or baked to add strength.