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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 ]
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.
Polished slab of bowenite serpentine, a variety of antigorite.. Bowenite is a hard, compact variety of the serpentinite species antigorite (Mg 3 (OH)O 4 Si 2 O 5). [1] Classed as a semi-precious gemstone, [2] it has been used for tools, weapons and jewellery by the Māori in New Zealand, [3] [4] and for jewellery by Fabergé. [5]
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
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 ...
Serpentine soil is an uncommon soil type produced by weathered ultramafic rock such as peridotite and its metamorphic derivatives such as serpentinite. More precisely, serpentine soil contains minerals of the serpentine subgroup, especially antigorite, lizardite, and chrysotile or white asbestos, all of which are commonly found in ultramafic ...
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.
Antigorite is found in low-temperature, high-pressure (or high-deformation) environments, including both extensional and compressional tectonic regimes. [6] Serpentines are commonly found in the ultramafic greenschist facies of subduction zones, and are visible on the Earth's surface through secondary exhumation.