{"id":630,"date":"2018-06-27T12:49:43","date_gmt":"2018-06-27T16:49:43","guid":{"rendered":"https:\/\/www2.whoi.edu\/site\/groundwater\/?page_id=630"},"modified":"2021-08-17T13:25:43","modified_gmt":"2021-08-17T17:25:43","slug":"actinium-227-magma-transit-times","status":"publish","type":"page","link":"https:\/\/www2.whoi.edu\/site\/groundwater\/projects\/actinium-227-magma-transit-times\/","title":{"rendered":"Melt generation and transport during basalt petrogenesis"},"content":{"rendered":"\n\n<h1>Melt Generation and Transport During Basalt Petrogenesis:<\/h1>\n<h3>Constraints from Measurements of\u00a0<sup>227<\/sup>Ac<sup>-231<\/sup>Pa Activity Ratios<\/h3>\n<p>Uranium-series isotopes have provided unique insight into geochemical rates and processes during genesis of basaltic magma from the earth&#8217;s mantle. Specifically, recent measurements of the longer-lived isotopes of the U-decay series have placed important constraints on melting rates (related to solid mantle upwelling rates) and melt fractions. However, there have been relatively few measurements of the shorter-lived isotopes of the U decay series in basaltic samples. As a result, time-dependant parameters such as melt transport rates and magma storage times are not well known. To better constrain these parameters, under this SGER award, the PIs propose to measure short-lived\u00a0<sup>227<\/sup>Ac (t1\/2 =21.8 y) in young basaltic samples from mid-ocean spreading centers and intraplate volcanoes like Hawaii. This geochronologic system has the potential to be an important chronometer for dating of young mid-ocean ridge basalts in the time range of 10-100 years. Development of a new counting technique for\u00a0<sup>227<\/sup>Ac has simplified its analysis making this research possible for the first time.<\/p>\n<p>Dulaiova, H.D., K.W. Sims, and M.A. Charette. (2013) A new method for the determination of low-level actinium-227 in geological samples.\u00a0<em>Journal of Radioanalytical and Nuclear Chemistry<\/em>,\u00a0<strong>296<\/strong>, 279-283.<\/p>\n<p>Sims, K.W.W., S. Pichat, M. Reagan, P. Kyle, H. Dulaiova, N. Dunbar, J. Prytulak, G. Sawyer, G. Layne, J. Blichert-Toft, P. Gauthier, M. Charette, and T. Elliott. (2013) On the timescales of magma genesis, melt evolution, crystal growth rates, and magma degassing in the Erebus volcano magmatic system using the\u00a0<sup>238<\/sup>U,\u00a0<sup>235<\/sup>U, and\u00a0<sup>232<\/sup>Th decay series.\u00a0<em>Journal of Petrology<\/em>,\u00a0<strong>54<\/strong>, 235-271.<\/p>\n\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n\t\t\t\t<a href=\"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-content\/uploads\/sites\/49\/2018\/06\/ken_down_52384.jpg\" target=\"_self\" rel=\"noopener noreferrer\">\n\t\t\t\t<img loading=\"lazy\" src=\"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-content\/uploads\/sites\/49\/2018\/06\/ken_down_52384.jpg\" alt=\"Man climbing up ice using instruments\" height=\"165\" width=\"250\" title=\"ken_down_52384\" \/>\n\t\t\t\t<\/a>\n\t\tUniversity of Hamburg researchers designed &#8220;tube&#8221; moorings that make way for icebergs, then bounce back up, affording protection for instruments taking measurements near the surface\n\t<h3>Funding Agencies<\/h3>\n<a href=\"https:\/\/www.nsf.gov\"><img loading=\"lazy\" src=\"https:\/\/www2.whoi.edu\/site\/bb-templates\/wp-content\/uploads\/sites\/2\/2016\/09\/nsf.png\" alt=\"nsf logo\" width=\"80\" height=\"80\" \/><\/a> We would like to extend our thanks to The National Science Foundation for their generous support of this project.<br \/>\nK. Sims co-principal Investigator.\n\n","protected":false},"excerpt":{"rendered":"<p>Melt Generation and Transport During Basalt Petrogenesis: Constraints from Measurements of\u00a0227Ac-231Pa Activity Ratios Uranium-series isotopes have provided unique insight into geochemical rates and processes during genesis of basaltic magma from the earth&#8217;s mantle. Specifically, recent measurements of the longer-lived isotopes of the U-decay series have placed important constraints on melting rates (related to solid mantle&hellip;<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":21,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/pages\/630"}],"collection":[{"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/comments?post=630"}],"version-history":[{"count":3,"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/pages\/630\/revisions"}],"predecessor-version":[{"id":877,"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/pages\/630\/revisions\/877"}],"up":[{"embeddable":true,"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/pages\/21"}],"wp:attachment":[{"href":"https:\/\/www2.whoi.edu\/site\/groundwater\/wp-json\/wp\/v2\/media?parent=630"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}