Volcanic and thermogenic emissions from the North Atlantic Igneous Province: Insights from melt and fluid inclusions

Abstract

Throughout the Phanerozoic, temporal coincidence between Large Igneous Provinces (LIPs) and climate perturbations points to a potential causality via volcanic and thermogenic emissions. The best documented example of this association consists in the North Atlantic Igneous Province (NAIP) and the Paleocene–Eocene Thermal Maximum (PETM), which represents the most recent natural analogue for anthropogenic greenhouse gas emissions flux [1]. The NAIP extends from Greenland to the Scandinavian Peninsula and the British Isles, but the East Greenland margin preserves one of the most studied magmatic systems: the Skaergaard intrusion and its overlying 6-8 km thick lava pile, close to the centre of the province [2]. Melt and fluid inclusions within intrusive and effusive rock samples from East Greenland were screened and selected to investigate their volatile content by confocal Raman microspectroscopy. In the effusive rock samples, phenocrysts of olivine, clinopyroxene and sometimes plagioclase host primary melt inclusions containing gas bubbles. On the contrary, in the intrusive rock samples, most of primary melt inclusions within olivine crystals do not contain any gas bubble. However, in these rock samples, quartz often occurs as interstitial subhedral crystals or forms graphic textures with alkali feldspar, and hosts abundant multiphase (i.e., gaseous ± liquid ± solid phases) fluid inclusions. In general, the investigation of volatile species preserved by melt and fluid inclusions within magmatic minerals allows the reconstruction of volcanic and thermogenic emissions from LIPs [3; 4]. Here, we present preliminary data of this ongoing project that aims to constrain the role of volatiles from the NAIP in driving the synchronous PETM.   [1] Jones et al. (2019), Nat. Commun. 10, 5547. [2] Larsen & Tegner (2006), Lithos 92, 181–197. [3] Capriolo et al. (2020), Nat. Commun. 11, 1670. [4] Capriolo et al. (2021), Nat. Commun. 12, 5534.