{"id":21663,"date":"2024-03-19T05:01:14","date_gmt":"2024-03-18T23:31:14","guid":{"rendered":"https:\/\/vajiramandravi.com\/current-affairs\/?p=21663"},"modified":"2025-04-06T13:45:47","modified_gmt":"2025-04-06T08:15:47","slug":"barberton-greenstone-belt","status":"publish","type":"post","link":"https:\/\/vajiramandravi.com\/current-affairs\/barberton-greenstone-belt\/","title":{"rendered":"What is the Barberton Greenstone Belt?"},"content":{"rendered":"<h2>About Barberton Greenstone Belt<\/h2>\n<ul>\n<li>It is situated on the\u00a0eastern edge of the Kaapvaal Craton in South Africa.<\/li>\n<li>It is\u00a0known for its gold mineralisation\u00a0and for its\u00a0komatiites, an unusual type of\u00a0ultramafic volcanic rock named after the Komati River that flows through the belt.\u00a0<\/li>\n<li>Some of the oldest exposed rocks on Earth (greater than 3.6 Ga) are located in the Barberton Greenstone Belt of the Eswatini\u2013Barberton areas, and these\u00a0contain some of the oldest traces of life on Earth, second only to the Isua Greenstone Belt of Western Greenland.<\/li>\n<li>The\u00a0Makhonjwa Mountains make up 40% of the Baberton belt.<\/li>\n<li>Geological sampling indicates that\u00a0some rock formations\u00a0in these mountains\u00a0are 3.2 to 3.6 billion years old.<\/li>\n<\/ul>\n<h2>What are ultramafic rocks?<\/h2>\n<ul>\n<li>Ultramafic (or ultrabasic) rocks are\u00a0dark-colored igneous and meta-igneous rocks that are\u00a0rich in minerals containing magnesium and iron (&#8220;mafic&#8221; minerals) and have a relatively\u00a0low content of silica.<\/li>\n<li>They are generally composed of more than 90 percent mafic minerals\u2014that is, they have a high content of magnesium oxide (more than 18 percent MgO) and iron oxide (FeO). Their silica content is less than 45 percent, and their potassium content is low.<\/li>\n<li>The\u00a0Earth&#8217;s mantle is thought to be composed of ultramafic rocks.<\/li>\n<li>Most of the exposed ultramafic rocks have been\u00a0found in orogenic (mountain-forming) belts.\u00a0<\/li>\n<\/ul>\n<hr \/>\n<h3>Q1) What are Igneous Rocks?<\/h3>\n<p>Igneous rocks are one of three main types of rocks (along with sedimentary and metamorphic), and they include both intrusive and extrusive rocks.Igneous rocks form when magma (molten rock) cools and crystallizes, either at volcanoes on the surface of the Earth or while the melted rock is still inside the crust. All magma develops underground, in the lower crust or upper mantle, because of the intense heat there. Igneous rocks can have many different compositions, depending on the magma they cool from.<\/p>\n<p><strong>Source: <\/strong><a href=\"https:\/\/www.livescience.com\/planet-earth\/oldest-evidence-of-earthquakes-found-in-strange-jumble-of-33-billion-year-old-rocks-from-africa\" target=\"_blank\" rel=\"nofollow noopener\"><u>Oldest evidence of earthquakes found in strange jumble of 3.3-billion-year-old rocks from Africa<\/u><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Barberton Greenstone Belt is situated on the eastern edge of the Kaapvaal Craton in South Africa.<\/p>\n","protected":false},"author":5,"featured_media":21664,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":{"0":"post-21663","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-upsc-prelims-current-affairs","8":"no-featured-image-padding"},"acf":[],"_links":{"self":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/21663","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/comments?post=21663"}],"version-history":[{"count":0,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/21663\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media\/21664"}],"wp:attachment":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media?parent=21663"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/categories?post=21663"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/tags?post=21663"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}