Using olivine as a probe into early igneous and mantle melting processes: combining in situ oxygen isotopes with minor and trace-element compositions of olivine from Circum-Mediterranean Cenozoic magmatic provinces

使用橄榄石作为早期火成岩和地幔熔融过程的探针：将原位氧同位素与来自环地中海新生代岩浆省的橄榄石的微量和微量元素成分相结合

• 批准号: 283406641
• 负责人: Dr. Dejan Prelevic, Ph.D., since 10/2016
• 金额: --
• 依托单位: Institut für Geowissenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/283406641?language=en
• 关键词: Using; olivine; probe; into; early

The identity and origin of mantle components tapped by Circum-Mediterranean Cenozoic orogenic and anorogenic magmatism will be evaluated on the basis of comprehensive in situ oxygen isotope combined with in situ major, minor and trace element measurements on genetically different olivine populations (mantle xenocrysts, phenocrysts, cumulitic olivine etc). The in situ isotopic and elemental compositions of the olivines will be determined on identical spots circumventing low-temperature falsification of the genuine composition of the bulk rock by alteration. Moreover, olivine represents an archive of early magmatic processes offering less homogenized account of the melting process compared to lavas. Oxygen isotopes will indicate if a source rock experienced metasomatism and it will signalize derivation from continental (18O enrichment) or altered oceanic crust (variable, but often 18O depletion). In combination with elemental compositions, this approach represents a powerful tool to discriminate and quantify different geochemical components in particular to track recycled crustal components in the source of the Circum-Mediterranean Cenozoic magmatic province. It is expected that the suggested in situ analytical approach applied for the first time on olivine is a breakthrough in olivine research and substantiates the application of olivine as a relevant petrogenetic indicator for early magmatic processes.

环地中海新生代造山和非造山岩浆活动所挖掘的地幔成分的身份和起源，将在综合原位氧同位素结合原位主要，次要和微量元素测量的基础上，对不同的橄榄石种群（地幔捕虏晶，斑晶，堆晶橄榄石等）进行评价。橄榄石的原位同位素和元素组成将在相同的地点进行测定，以避免通过蚀变对大块岩石的真实组成进行低温伪造。此外，橄榄石代表了早期岩浆过程的档案，与熔岩相比，提供了较少的熔融过程的均匀性。氧同位素将指示源岩是否经历了交代作用，它将标志着来自大陆（18O富集）或蚀变洋壳（变量，但通常是18O亏损）。结合元素组成，这种方法代表了一个强大的工具来区分和量化不同的地球化学成分，特别是跟踪循环地壳成分的源环地中海新生代岩浆省。首次提出的橄榄石原位分析方法是橄榄石研究领域的一个突破，为橄榄石作为早期岩浆作用的成岩指示剂的应用提供了依据。