as the article states, the petrographic compositional profile is changing
as unlike the mixed partial melting of the majority of other icelandic volcanoes, this one seem to be sourced from down at the mantle boundary, possibly as an old pathway that hadn't been used for 14,000 year was reopened by a recent earthquake. So when you have varying mg mafic minerals, as stated, you have varying viscosities, and hence varying sorts of eruptions. The one characteristic of these deep sourced volcanoes is that they tend to be long lasting and bring up lots of rock, some erupting for thousands of years, so in this context I think they were talking about shield volcanoes in terms of prominence, as they are some of the largest volcanoes on earth. shield is more of a morphological descriptor, some are quite pyroclastic, or have suffered cone collapse. And even volcanoes like mauna kea and loa are in what's called their post shield phase, they had substantial large pyroclastic eruptions in their earlier phases, with large ash deposits like the pahala ash layers showing they blew their tops as good as the next volcano
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cumquat may will not be commenting further on the allegations, Wed 9 Jun 2021, 0:09,
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