Edward W. Marshall

Carbon Isotope and Abundance Systematics Reveal an Insignificant Crustal Sink of Mantle‐Derived CO2 in On‐Land Rift Zone Geothermal Systems CO2 in carbonates of the Iceland crust predominantly originates from the mantle Only 1%–10% of mantle-derived CO2 that degasses along the Iceland rift zone is permanently fixed into carbonates C...

New article just published 🤗 Find out why the Iceland rift may provide such a significant source for mantle-derived CO2! agupubs.onlinelibrary.wiley.com/doi/10.1029/...

#geochemistry

Modeling seawater-basalt interaction at 10–100 °C: Controlling parameters and effects on the composition of the oceanic crust and seawater Chemical reactions and element mobilization during seawater-basalt interaction play a central role in regulating global element fluxes between seawate…

New publication out on the interaction of seawater with oceanic crust! 🌊 🪨 We show how temperature, reaction progress, time and crystallinity of the crust affect elemental fluxes! www.sciencedirect.com/science/arti...

Interlaboratory reproducibility of ID-TIMS U–Pb geochronology evaluated with a pre-spiked natural zircon solution Abstract. The highest precision and accuracy in U–Pb geochronology is achieved using isotope dilution thermal ionisation mass spectrometry (ID-TIMS), a technique which owes its reliability to precise ...

Happy to share the long-awaited results of our community experiment comparing high-precision ID-TIMS U-Pb lab performance🧪⚒️
We do pretty well but as ever there is room for improvement 🤓 Stay tuned!

doi.org/10.5194/gchr...

Oh I see! Yeah you are right-- it does make it seem like those types don't exist. I actually remember being confused about this when I was a student.

It is? I thought it was called tachylite. I thought true obsidian was always silicic. In my head the Venn diagram would have a big circle for volcanic glass with tachylite and obsidian as non-overlapping circles within the volcanic glass circle.

I guess they are writing to integrate the text better with rocks that students likely have in their classroom or might be familiar with prior to the class. They are putting in the ladder at the shallow end of the pool.

I should say-- the one cartoon figure, not figures. Anyway, definitely not as depicted-- the core-mantle boundary being stretched to the surface.

The title of the artcle and the figures of the article are misleading. The core isn't leaking out at the surface. Tiny fractions of core material are entrained into the mantle, and this core-contaminated mantle material eventually is melted beneath some hot spots.

They are really cool!

What are these? Are they glomercrysts weathering out of a lava?

@vaccinium-sultan.bsky.social is always posting awesome xenoliths. They aren't folds or thin sections, but they are rocks!

Whoa this is really cool!

Mush Disaggregation and Dike Propagation Timescales at Active Volcanoes: Evidence from the 2022–2023 Fagradalsfjall Eruptions Abstract. The architectures of magma plumbing systems and timescales of magmatic processes are fundamental to understanding volcanic eruption dynamics. Thi

The typeset version of the 2022-2023 Fagradalsfjall paper is out, so let’s go over the main points of the paper 🌋

Crystal mush processes and crustal magmatism Nature Reviews Earth & Environment - Crystal mush processes are key to magmatic differentiation, volcanic system behaviour and some mineral resources. This Review discusses the processes...

Interested in crystal mushes? New review paper just out: rdcu.be/eo9pC
Great to be part of the team!

Amazing work by @albertocaracciolo.bsky.social . It's the coolest diffusion timescale work I've ever seen. You can see each eruption priming and how they are related to one another. Just super cool science.

Mush disaggregation and dike propagation timescales at active volcanoes – Evidence from the 2022-2023 Fagradalsfjall eruptions Abstract. The architectures of magma plumbing systems and timescales of magmatic processes are fundamental to understanding volcanic eruption dynamics. Thi

🚨🌋New paper on the geochemistry and petrology of the 2022–23 Fagradalsfjall eruptions on the Reykjanes Peninsula, Iceland. We study temporal variations in the magmatic plumbing system and link diffusion timescales to monitoring signals, tracing the timing of mush disaggregation and dike propagation

Hmm tricky! I tried to think of relatively recent and/or short papers.

A process-oriented approach to mantle geochemistry The numerous chemical and isotopic studies of oceanic basalts have shaped our perception of mantle geochemistry over the last six decades. As partial …

Oh oops www.sciencedirect.com/science/arti...

This proposed budget is a policy statement, not an appropriation.
There are still a lot of steps and potential changes ahead before it becomes one. This is not a time to sit quietly, team. Let's go.

Magmatic filtering of mantle compositions at mid-ocean-ridge volcanoes - Nature Geoscience The Earth's mantle constitutes over 80% of the planet's volume and is a key reservoir in global geochemical cycling. An overview of the progress in understanding the generation of mid-ocean-ridge basa...

I'm not really sure what you're looking for, or even if such a paper exists, but here are some contenders that popped into my head.

www.nature.com/articles/nge...

www.nature.com/articles/nge...

www.nature.com/articles/s41...

This was written about media content, but the same can be said for scientific content. When the incentive structure is based around numbers of papers and numbers of citations, it's a system that assumes quantity means quality. It's ripe for abuse by AI, which can do quantity really well...

Thanks Emily!!

Thanks! It was by far the most exciting science I've ever done! It's true that the earliest lavas are buried- maybe we should be drilling and collecting core from more lava shields! The cores from the HSDP borehole were super cool and revealing, for example.

The Petrology and Geochemistry of the 2021 Fagradalsfjall Eruption, Iceland: An Eruption Sourced From Multiple, Compositionally Diverse, Near‐Moho Sills We use high frequency sampling to observe rapid changes in lava composition during the 183 day 2021 Fagradalsfjall eruption The eruption was sourced from 12 to 15 km depth, corresponding to the l...

Cpx-melt and melt inclusion volatile saturation pressures say they come from the lower crust or near Moho! Probably syn-eruptive decompacted crystal mushes! agupubs.onlinelibrary.wiley.com/doi/full/10....

Yes definitely!

I don't think it's your fault. I think the article has quite a bit of spin. I just hope the court cases go through and money gets eventually spent.

I think the data is the amount of funding allocated by the NSF from Jan-May from 2025 compared to previous years. The article is written like there are actual budget cuts, but the reality is that NSF is at a standstill due to chaos and illegal impoundment. The budget could still spent eventually?

Pacific hotspots reveal a Louisville–Ontong Java Nui tectonic link - Nature Geochemistry and geochronology show that Samoa and Rurutu–Arago are the longest-lived Pacific hotspots, providing better constraints on plate rotation and support for a link between the Louisville vol...

New paper out by my team, led originally by the late Jasper Konter, an amazing human being and scientist, and with important contributions from the late Paul Wessel, both of whom we lost during review.

The whole team stepped up to get this paper to the finish line.

www.nature.com/articles/s41...

Opinion | Universities Gave Us the iPhone, the Jet Engine and Gatorade. We’re Tossing That Away. The postwar compact on research that powered America’s economic and military dominance is under threat.

Former Columbia provost Jonathan Cole-"Columbia’s leaders have weakened...our leadership among the greatest educational institutions in the world...If we don’t resist collectively by all legal means...we are apt to see the destruction of our most revered institutions” www.nytimes.com/2025/03/24/o...