{"id":8157,"date":"2021-12-01T01:50:24","date_gmt":"2021-12-01T06:50:24","guid":{"rendered":"https:\/\/spaceandplanetarynewswire.com\/?p=8157"},"modified":"2021-12-01T01:50:24","modified_gmt":"2021-12-01T06:50:24","slug":"recycling-of-tectonic-plates-a-key-driver-of-earths-oxygen-budget","status":"publish","type":"post","link":"https:\/\/spaceandplanetarynewswire.com\/?p=8157","title":{"rendered":"Recycling of Tectonic Plates a Key Driver of Earth\u2019s Oxygen Budget"},"content":{"rendered":"
Parinacota Volcano, in the Atacama Desert of Chile.<\/figcaption><\/figure>\n

A new study co-led by a Cornell researcher has identified serpentinite \u2013 a green rock that looks a bit like snakeskin and holds fluids in its mineral structures \u2013 as a key driver of the oxygen recycling process, which helped create and maintain the sustaining atmosphere for life on Earth.<\/p>\n

\u201cThis cycle is a really a big deal,\u201d said Esteban Gazel<\/a>, associate professor of earth and atmospheric sciences in Cornell\u2019s College of Engineering, and co-lead author on the study. \u201cIn the end, we\u2019re talking about the budget of oxygen on the planet and how that gets balanced through processes like subduction.\u201d<\/p>\n

Earth is constantly recycling its life-giving supply of water and oxygen as tectonic plates sink, or subduct, deep into the planet. Elements are carried down as one piece of the planet\u2019s crust slips below another, and resurface through the resulting volcanoes.<\/p>\n

It\u2019s a critical process, but how, exactly, subduction recycles oxygen and allows it to interact with other elements has always been a topic of debate among geoscientists.<\/p>\n

The new finding was published Nov. 26 in Science Advances<\/a> <\/em>and changes how geoscientists understand the underlying process of Earth\u2019s geochemical cycle. The reason geoscientists had, until now, failed to make this discovery was because of something the COVID-19 pandemic had provided Gazel \u2013 time to look at massive amounts of data.<\/p>\n

Using volcanoes to probe the deep Earth, past studies have examined oxygen levels in the Earth\u2019s mantle \u2013 the magma-filled layer directly under the crust \u2013 for clues. Some geoscientists have pointed to increased oxidation below volcanic arcs, where the hydrated oceanic lithosphere sinks into the mantle. A leading theory had been that ocean water delivering hydrogen into the mantle was influencing its oxidation state, but the new study found that oxygen is entering the mantle in fluids derived from \u201cheated and pressurized\u201d serpentinite rocks.<\/p>\n

Below the sea floor, the process of serpentinization creates rocks that trap highly oxidizing fluids inside, and these serpentinites eventually get subducted back into the mantle.<\/p>\n

\u201cEventually, those serpentinite juices are going to be squeezed from the slab,\u201d said Gazel, who is also a faculty fellow at the Cornell Atkinson Center for Sustainability.<\/a> \u201cDepending on the angle and the thermal conditions of the subducting slab, those fluids are released and they oxidize the mantle below volcanoes.\u201d<\/p>\n

With travel restrictions and his laboratory under construction, Gazel and his colleague Yuxiang Zhang from the Institute of Oceanology, Chinese Academy of Sciences spent time in 2020 carefully analyzing every existing dataset for single arcs and their lava compositions. Adding to the analysis were serpentinization expert Frieder Klein and chemical thermodynamics expert Glenn Gaetani, both scientists from the Woods Hole Oceanographic Institution.<\/p>\n

\u201cWe were looking at the correlation with different processes,\u201d Gazel said. \u201cFor instance, there were some regional datasets that correlated the thickness of the crust with oxidation, but it just didn\u2019t make sense once we made our study global.\u201d<\/p>\n

Once enough datasets had been combined, certain correlations were eliminated while the correlation between serpentinization related fluids and oxidization became evident. Specifically, the subduction system\u2019s thermodynamic conditions and geometry proved to control the dehydration of serpentine and the oxidation state of the mantle, with steeper, colder subduction zones providing more oxidization.<\/p>\n","protected":false},"excerpt":{"rendered":"

A new study co-led by a Cornell researcher has identified serpentinite \u2013 a green rock that looks a bit like snakeskin and holds fluids in its mineral structures \u2013 as a key driver of the oxygen recycling process, which helped create and maintain the sustaining atmosphere for life on Earth. \u201cThis cycle is a really…<\/p>\n","protected":false},"author":71,"featured_media":8159,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"fifu_image_url":"https:\/\/news.cornell.edu\/sites\/default\/files\/styles\/story_thumbnail_xlarge\/public\/1129_mantle_0.jpg?itok=VLi43hQJ","fifu_image_alt":"Auto Draft","footnotes":""},"categories":[216],"tags":[],"class_list":["post-8157","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-discovery"],"_links":{"self":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/8157","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/users\/71"}],"replies":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=8157"}],"version-history":[{"count":1,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/8157\/revisions"}],"predecessor-version":[{"id":8158,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/8157\/revisions\/8158"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/media\/8159"}],"wp:attachment":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=8157"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=8157"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=8157"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}