The first order information on palaeogeography, which contributes to other scientific fields, can be obtained from the reconstruction of the previous arrangement of continents. The study of palaeogeography therefore relies on precise dating of short-lived mantle-generated magmatic events, which have high preservation potential and provides information on their orientation. This study presents high-resolution U-Pb baddeleyite age for a new dyke sample from Cote d'Ivoire in West Africa using Thermal Ionisation Mass Spectrometry (TIMS) for precise and accurate result. No date was generated from the N-S trending sample Mon-1 due to the lack of baddeleyites and zircon crystals, however, the NW-SE trending sample SP-22 yields an age of 182.29 ± 0.12 Ma. This is a contrast to the Central Atlantic Magmatic Province (CAMP) ages of around -200 Ma commonly associated with the West African Craton. The age better correlates to the nearby Karoo-Ferrar Large Igneous Province (LIP) which had the bulk of its magmatism between 173-167 Ma. This study also used an integrated approach, comparing the Cote d'Ivoire samples with compilation of geochemical datasets for CAMP and Karoo, as well as and georeferenced magmatism datasets for nearby contemporary dates with sample SP-22. The geochemical analyses were able to discriminate between the two different LIP population but were not able to confirm the origin of the Cote d'Ivoire samples. The magmatism dataset supports the connection with the Karoo-Ferrar LIP, with the reconstruction of the synchronous magmatism showing a -14,400 km linear trend across Gondwana.
|15 Nov 2018
|Unpublished - 2018
- Embargoed from 11/03/2019 to 11/03/2020. Made publicly available on 11/03/2020.