An "ophiolite" is a section of the Earth's oceanic crust and the underlying upper mantle that has been uplifted and exposed above sea level and often emplaced onto continental crustal rocks. "Ophio" is Greek for "snake" , and "lite" means "stone" from the Greek "lithos" , after the often-green-color rocks that make up many ophiolites. The term ophiolite was originally used by Alexandre Brongniart for an assemblage of green rocks in the Alps; Gustav Steinmann later modified its use to include serpentine, pillow lava, and chert , again based on occurrences in the Alps. The term was little-used in other areas until the late 1950s to early 1960s, with the recognition that this assemblage provided an analog for oceanic crust and the process of seafloor spreading. This recognition was tied to two events: the observation of magnetic anomaly stripes on the seafloor, parallel to oceanic ridge systems, interpreted by Frederick Vine and Drummond Matthews to represent the formation of new crust at the oceanic ridge and its subsequent symmetric spreading away from that ridge, and the observation of a sheeted dike complex within the Troodos ophiolite by Ian Graham Gass and co-workers, which must have formed by repetitive extension of crust and intrusion of magma, resulting in a formation consisting of 100% dikes with no older wall rocks preserved within the complex. Moores and Vine concluded that the sheeted dike complex at Troodos could form only by a process similar to the seafloor spreading proposed by Vine and Matthews. Thus, it became widely accepted that ophiolites represent oceanic crust that had been emplaced on land. Wiz Science™ is "the" learning channel for children and all ages. SUBSCRIBE TODAY Disclaimer: This video is for your information only. The author or publisher does not guarantee the accuracy of the content presented in this video. USE AT YOUR OWN RISK. Background Music: "The Place Inside" by Silent Partner (royalty-free) from YouTube Audio Library. This video uses material/images from https://en.wikipedia.org/wiki/Ophiolite, which is released under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . This video is licensed under Creative Commons Attribution-Share-Alike License 3.0 http://creativecommons.org/licenses/by-sa/3.0/ . To reuse/adapt the content in your own work, you must comply with the license terms.

• published: 02 Sep 2015
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