E. N. Kozlov, E. N. Fomina, M. Yu. Sidorov, A. V. Gudkov, V. V. Kolobov
{"title":"He Isotopic Composition and 4He/20Ne Ratio of Pyrite and Magnetite of Explosive Carbonatite Breccia of the Sallanlatva Massif, Kola Region","authors":"E. N. Kozlov, E. N. Fomina, M. Yu. Sidorov, A. V. Gudkov, V. V. Kolobov","doi":"10.1134/s1028334x24603183","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The He isotopic composition and the He and Ne ratio of fluid inclusions in magnetite and pyrite from carbonatite breccias of the Sallanlatva alkali-ultramafic complex of the Kola alkaline province (Northwest Russia) are studied using the step-crushing method. The results indicate the highly likely involvement of fluids from several sources trapped in various proportions during the formation of the Sallanlatva explosive carbonatite breccias. The <i>R</i>/<i>Ra</i> ratio, where <i>R</i> is the measured <sup>3</sup>He/<sup>4</sup>He ratio and <i>Ra</i> of 1.382 × 10<sup>–6</sup> is the same ratio of atmospheric air, reaches 2.3, which is a reliable indicator of the presence of mantle gases. A low (1–44) <sup>4</sup>He/<sup>20</sup>Ne ratio allows us to suggest the involvement of atmospheric gases dissolved in paleometeoric waters. A combination of these two facts favors a hypothesis of the phreatomagmatic nature of the studied breccias, i.e., their formation at the expense of interaction between the intruding hot orthomagmatic fluids and meteoric waters with dissolved atmospheric gases.</p>","PeriodicalId":11352,"journal":{"name":"Doklady Earth Sciences","volume":null,"pages":null},"PeriodicalIF":0.7000,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Doklady Earth Sciences","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1134/s1028334x24603183","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
The He isotopic composition and the He and Ne ratio of fluid inclusions in magnetite and pyrite from carbonatite breccias of the Sallanlatva alkali-ultramafic complex of the Kola alkaline province (Northwest Russia) are studied using the step-crushing method. The results indicate the highly likely involvement of fluids from several sources trapped in various proportions during the formation of the Sallanlatva explosive carbonatite breccias. The R/Ra ratio, where R is the measured 3He/4He ratio and Ra of 1.382 × 10–6 is the same ratio of atmospheric air, reaches 2.3, which is a reliable indicator of the presence of mantle gases. A low (1–44) 4He/20Ne ratio allows us to suggest the involvement of atmospheric gases dissolved in paleometeoric waters. A combination of these two facts favors a hypothesis of the phreatomagmatic nature of the studied breccias, i.e., their formation at the expense of interaction between the intruding hot orthomagmatic fluids and meteoric waters with dissolved atmospheric gases.
摘要 利用阶梯破碎法研究了科拉碱性省（俄罗斯西北部）萨兰拉特瓦碱性-超基性复合体碳酸盐岩角砾岩中磁铁矿和黄铁矿中流体包裹体的 He 同位素组成以及 He 和 Ne 比率。研究结果表明，在萨兰拉特瓦爆炸碳酸盐岩角砾岩的形成过程中，极有可能有来自不同来源的流体以不同比例滞留其中。R/Ra 比率（其中 R 是测量到的 3He/4He 比率，Ra 为 1.382 × 10-6 是大气中空气的相同比率）达到 2.3，这是地幔气体存在的可靠指标。较低的（1-44）4He/20Ne 比值使我们可以推断出溶解在古史水域中的大气气体的存在。综合这两个事实，我们倾向于假设所研究的角砾岩具有岩浆性质，即它们的形成是以侵入的热原岩流体和陨石水与溶解的大气气体之间的相互作用为代价的。
期刊介绍：
Doklady Earth Sciences is a journal that publishes new research in Earth science of great significance. Initially the journal was a forum of the Russian Academy of Science and published only best contributions from Russia. Now the journal welcomes submissions from any country in the English or Russian language. Every manuscript must be recommended by Russian or foreign members of the Russian Academy of Sciences.
京公网安备 11010802042870号
京ICP备2023020795号-1
分享
求助内容：
应助结果提醒方式：
扫码关注我们
