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Magmatic gas delivered by intraplate, hot-spot related volcanism offers important insight into the abundance and distribution of volatiles in the Earth's upper mantle (Aiuppa et al., 2021) and hence into the rates and mechanisms of volatile exchange in and out our planet (Dasgupta & Hirschmann, 2010). Hot-spot magmatic gases have long been recognized (Gerlach, 1982;Symonds et al., 1994) to exbibit CO 2 -richer (and H 2 O-poorer) compositions relative to arc magmatic gases (Fischer, 2008;Fischer & Chiodini, 2015;Oppenheimer et al., 2014;Taran & Zelenski, 2015), attesting for the presence of a carbon-rich mantle reservoir (Aiuppa et al., 2021, and references therein) at depths higher than the shallow (<50 km) Depleted Mantle (DM) sampled by MORBs (Mid-Ocean Ridge Basalts;Hauri et al., 2019). Combined with the specific trace element and radiogenic isotope signatures of hot-spot volcanic rocks (Hoffman, 2003;Zindler & Hart, 1986), the composition of intraplate magmatic gases may thus provide unique information on volatiles' heterogeneities in mantle plumes. Unfortunately, however, the existing data set for hot-spot magmatic gases is still limited (Aiuppa et al., 2021), detailed information being available for only the

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&lt;p&gt;Understanding the pre-eruptive volatile contents in magmas is critical to charactering the magmatic plumbying systems that feed acative volcanoes, and is key to volcano monitoring and volcanic hazard assessment. Silicate melt inclusions (MIs) hosted in primitive minerals are a powerful tool to definite parental melt volatile contents, and to track the volatile degassing path upon magma ascent and decompression.&lt;/p&gt; &lt;p&gt;Here, we apply different analyses (Raman Spectroscopy, Nano SIMS, Electron microprobe, Laser Ablation ICPMS) for the characterisation of major and trace elements and volatiles in silicate melt inclusions entrapped in minerals from recently erupted tephra by Fogo Volcano in Cape Verde archipelago, one of the most active intraplate volcanic systems on Earth.Our aims are to (i) characterise the pressure-dependent magma compositional changes taking place during magma storage and ascent, (ii) model magmatic degassing and (iii) constrain the magmatic source, and the rates/modes of magma ascent prior and during eruption.&lt;/p&gt; &lt;p&gt;Seventeen MIs hosted in twelve olivine phenocrysts (Fo&lt;sub&gt;79-85&lt;/sub&gt;) were examined from tephra samples of two distinct periods of the last 10 ky of activity of the volcano. In detail, we studied basanitic (SiO&lt;sub&gt;2&lt;/sub&gt; ~42 wt.%, MgO ~4.8 wt. %) and alkali-rich (Na&lt;sub&gt;2&lt;/sub&gt;O + K&lt;sub&gt;2&lt;/sub&gt;O = 6.9 wt.%) tephra samples of S&amp;#227;o Jorge (early Holocene activity, ~10 ka) and of the most recent eruptions (1951 and 2014/15).&lt;/p&gt; &lt;p&gt;Results reveal high concentrations of incompatible trace elements (e.g.,&amp;#732;70 ppm Nb) and dissolved volatiles ( &amp;#732;2.1 wt.% H&lt;sub&gt;2&lt;/sub&gt;O and &amp;#8805;1 wt.% CO&lt;sub&gt;2&lt;/sub&gt;) in the parental (un-degassed) magma. We use different H&lt;sub&gt;2&lt;/sub&gt;O-CO&lt;sub&gt;2&lt;/sub&gt; solubility models to estimate MI entrapment pressures along the magma plumbing system. The deepest entrapment pressures of &amp;#160;&amp;#732;1000-1400 MPa (corresponding to &amp;#160;&amp;#732; 30-46 km) are recorded in Holocene products, while the inclusions from the recent eruptions indicate shallower entrapment pressures of &amp;#160;&amp;#732; 350-1100 MPa (&amp;#732; 11-35km). These entrapment pressure data, combined with previous independent barometric results, demonstrate a relatively deep (30-40 km) magma source for Fogo eruptions. Our results are the first to unambiguously demonstrate the CO&lt;sub&gt;2&lt;/sub&gt;-rich nature of alkali-rich mafic melts feeding intraplate volcanism at Cape Verde.&lt;/p&gt;