Trip 37. 28.08.21. "This is the most primitive lava that we have seen since the last Ice Age" some 10,000 years ago, said Edward Marshall of the Institute of Earth Sciences.
"The lava produced by the eruption shows a composition differing from historical Reykjanes lavas. This could be caused by a new batch of magma arriving from a large magma reservoir at a depth of about 17–20 km (11–12 mi) at the Moho under Reykjanes..."
"From the composition of the magma sampled, it is believed that there is a discrete vent feeding the main lava flow from a depth of 17–20 kilometres (11–12 mi) from the Earth's mantle, and may be of a more primitive kind than those previously observed. The eruption may create a new shield volcano if it continues for long enough..."
"Scientists at the University of Iceland are analysing the lava. To date, they have reported that the lava is a primitive one (i.e. little magma evolution in the crust), indicative of a mantle source at a depth of 17 km to 20 km."
"New trace element and isotope analyses of the Geldingadalir lava provide further evidence that the magma feeding the Geldingadalir eruption has a different composition to the historical Reykjanes lavas. This shift in geochemistry potentially reflects a new and distinct batch of magma arriving from the mantle beneath Reykjanes.
The Geldingadalir lava is marked by lower concentrations of incompatible trace elements, lower LREE/HREE ratios, and less radiogenic Pb-isotope ratios. These data suggest a greater contribution from higher degree partial mantle melts, sampling more depleted/refractory mantle components..."
http://earthice.hi.is/1_april_2021_new_trace_element_and_isotope_analyses_geldingadalir_lava
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