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207Pb-excess in carbonatitic baddeleyite as the result of Pa scavenging from the meltстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 1 сентября 2021 г.
- Авторы: Ivanov A.V., Corfu F., Kamenetsky V.S., Marfin A.E., Vladykin N.V.
- Журнал: GEOCHEMICAL PERSPECTIVES LETTERS
- Том: 18
- Год издания: 2021
- Первая страница: 11
- Последняя страница: 15
- DOI: 10.7185/geochemlet.2117
- Аннотация: For the last two decades, the end of the voluminous phase of eruptions of the Siberian Traps large igneous province has been constrained by a U-Pb date of discordant baddeleyite collected from the Guli carbonatite intrusion with the assumption that the discordance resulted from unsupported 207Pb. In this study we have re-analysed baddeleyite from the same intrusion and found two types of discordance: (1) due to 207Pb-excess, and (2) radiogenic lead loss from high U mineral inclusions. The former implies that baddeleyite is an efficient scavenger of protactinium during crystallisation, leaving the magma depleted in this element. Together with a published high precision U-Pb date of 252.24 ± 0.08 Ma for the Arydzhansky Formation, our new date of 250.33 ± 0.38 Ma for the Guli carbonatite constrains the total duration of the voluminous eruptions of the Siberian Traps LIP at 1.91 ± 0.38 million years. The lower intercept of the (231Pa)/(235U) corrected discordance line yields a date of 129.2 ± 65.0 Ma, which points to the widespread Early Cretaceous rifting in East and Central Asia.
- Добавил в систему: Каменецкий Вадим Семенович