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Serpentinite thermal vents are a candidate for the environment in which life on Earth originated. [15] Most of the chemical reactions necessary to synthesize acetyl-CoA , essential to basic biochemical pathways of life, take place during serpentinization. [ 18 ]
The Lizard comprises three main units; the serpentinites, the 'oceanic complex' and the metamorphic basement. Since the pioneering work of Bromley [1] [2] and Kirby [3] these suites have been understood to represent a slice through a section of ocean crust, including the upper level of the mantle, thrust onto continental crust.
Because serpentinization lowers the density of the original rock, serpentinization may lead to uplift or exhumation of serpentinites to the surface, as has taken place with the serpentinite exposed at the Presidio of San Francisco following cessation of subduction. [43] Serpentinized ultramafic rock is found in many ophiolites.
An ophiolite is a section of Earth's oceanic crust and the underlying upper mantle that has been uplifted and exposed, and often emplaced onto continental crustal rocks. The Greek word ὄφις, ophis (snake) is found in the name of ophiolites, because of the superficial texture of some of them. Serpentinite especially evokes
Serpentinite most often forms in oceanic crust near the surface of the earth, particularly where water circulates in cooling rock near mid-ocean ridges: masses of the resulting ultramafic rock are found in ophiolites incorporated in continental crust near present and past tectonic plate boundaries. Serpentine soils are derived from ultramafic ...
Lateritic nickel ores formed by intensive tropical weathering of olivine-rich ultramafic rocks such as dunite, peridotite and komatiite and their serpentinized derivatives, serpentinite which consist largely of the magnesium silicate serpentine and contains approx. 0.3% nickel.
Ancient giant stromatolites used to be widespread in Earth’s Precambrian era, which encompasses the early time span of around 4.6 billion to 541 million years ago, but now they are sparsely ...
Microscopic view of skarn under crossed polarizers Hand sample of skarn containing serpentinite from the edge of the Alta Stock, Little Cottonwood Canyon, Utah. Skarns or tactites are coarse-grained metamorphic rocks that form by replacement of carbonate-bearing rocks during regional or contact metamorphism and metasomatism.