more-to-be-added

2025 ILSG Kilauea &c Field Trip Prep Notes

Kilauea: Dynamics of eruptions; Magma types

Kilauea erupted on 4 May 2018, from Haumaumau crater on its summit.
The rift eruption was driven by collapse of the central (shallow) magma chambers
The 2018 rift eruption had at least three different magmas:
- a highly evolved cool (1110°) viscous lava presumably from sources in the rift system [May 3-9]
- a less evolved hot (1130°) more fluid lava [May 17-18…]
- a very hot (1145°) magma lacking the cargo of low temperature crystals of the previous lavas, but with olvine with high levels of MgO indicating magma > 1250° somewhere in the feeder system

“The first two were the chemically evolved basalt of the initial fissures and the highly viscous andesite. Both are volumetrically minor sources that represent distinct pockets of old residual magma from Kīlauea’s east rift zone that evolved for more than 55 years, cooling and crystallizing at depth. The third and volumetrically more substantial source was less-evolved and hotter basalt of fissure 8. This source was similar in composition to the magma erupted at Kīlauea in the years before 2018 and was ultimately derived from the summit region. Draining and collapse of the summit by this voluminous eruption may have stirred up deeper, hotter parts of the summit magma system and sent mixed magma down the rift..”

Things I’ve learned re eruption dynamics and magmas

Not all lava from Hawaiian volcanoes is basaltic
Even that that is basaltic, changes in composition; each eruption features at least one, and often several, unique lava compositions.
Magma chambers are not homogeneous; this is presumably even more true of rift systems, where greater cooling can generate mushes of crystals
The 2018 Kilauea rift eruptions were driven by collapse of summit magma chambers.
The 2018 Kilauea rift eruption exhibited periodicity of 2-3 days (surges that began within minutes of caldera collapses 40 K upslope) and 5-10 minutes (pulses driven by local outgassing changes )
The dynamics of an eruption can be mapped into several stages
Lateral injection of magma into a rift zone (which forms, in Hawaii, due to volcano flanks sliding into ocean) leads to initial eruption
Pressure in the rift system leads to its elaboration – advancing dikes may capture pockets of highly evolved magma with mushes of low temperature crystals.
Magma injection into rifts, if large enough, can trigger slip on caldera ring faults
Ring fault slippage can add pressure to rift system and drive eruptive behavior at the rift
The central magma chamber appears to be vertically zoned. Initial eruptions of the rift zone (after flushing out pockets of magma that have evolved in the rifts) are composed of younger magmas from lower in the chamber; summit eruptions are fed by older, more evolved magma, higher up in the chamber.
The 2018 Kilauea eruption produced lava at volumes of 100 meters³/sec
Stages of Hawaiian volcanoes: pre-shield (alkalic basalt & basanite); shield (thoelitic basalt derived from both shallow plumbing system and deep plumbing system adjacent to mantle); post-shield (alkalic basalt from deep plumbing system adjacent to mantle (shallow plumbing has crystalized)); post erosional/rejuvenated (alkalic basalt, basanite & nephelinite from ???)

Order and nature of basaltic mineral & crystals

Common minerals that crystallize from basaltic magma, ordered by the temperatures at which they typically form:

*Olivine (Ca2(Mg,Fe)4O4): This is one of the first minerals to crystallize at the highest temperatures, typically around 1,200°C to 1,300°C. Olivine is rich in magnesium and iron and is often found in the earliest stages of crystallization in basaltic magmas.
*Olivine crystals are olive-green to yellow-green color. It often has a glassy or vitreous luster, and the crystals can be angular or rounded, with a granular texture when present in volcanic rocks. When olivine crystals are large enough, they often appear as transparent or translucent, sometimes with visible crystal faces, which are usually in a near-rectangular shape.
When olivine is exposed to oxidation, especially under conditions of high temperatures or in the presence of oxygen, it can alter to a yellowish or brownish hue, sometimes developing a reddish or rusty tint due to the formation of iron oxide minerals.
*Pyroxene (e.g., augite, diopside): Pyroxenes crystallize at slightly lower temperatures, generally around 1,100°C to 1,200°C. These minerals are composed of chains of tetrahedra and are rich in iron and magnesium.
     *Augite crystals are dark green to black, often with a shiny, almost metallic luster. It crystallizes in short prismatic crystals, which are often rectangular or blocky in shape. Augite crystals are typically larger than many other basaltic minerals and can be quite visible in coarse-grained basalts.
     Augite, being rich in iron, may undergo partial oxidation upon exposure to the atmosphere. The oxidation often causes a darkening of the color to a more brownish or reddish tint, though it rarely forms the rusty, reddish color seen in olivine. Augite may also exhibit a duller or more matte luster when oxidized.
     *Diopside is another pyroxene mineral, typically appearing as light green to pale green, although it can also be colorless or pale yellow. It forms prismatic crystals that are often transparent or translucent. Diopside crystals have a glassy or vitreous luster and typically display distinct striations or fine parallel lines on their crystal faces.
*Plagioclase feldspar (labradorite, anorthite): Plagioclase forms between 1,000°C and 1,100°C in basaltic magmas. This mineral can range from calcium-rich (anorthite) to sodium-rich (albite) compositions, with the more calcium-rich varieties crystallizing at higher temperatures.
* Plagioclase crystals vary from white to gray, and often have a glassy luster. They are typically tabular or blocky in shape and can show distinctive twin planes (known as albite twinning).
Magnetite (Fe3O4): Magnetite crystallizes at around 1,000°C to 1,100°C and often forms alongside other iron-rich minerals. It is a common accessory mineral in basaltic magmas.
* Crystals not typically visible in lavas
Ilmenite (FeTiO3): Ilmenite forms at slightly lower temperatures, typically around 900°C to 1,000°C. It is a titanium-iron oxide mineral and often occurs in basaltic lavas.
* Crystals not typically visible in lavas
Spinel (MgAl2O4): Spinel crystallizes at lower temperatures, usually around 900°C. It is a common accessory mineral in basaltic rocks, often forming in the lower temperature range of basaltic crystallization.
* Crystals not typically visible in lavas

These minerals crystallize according to Bowen’s reaction series, where early-formed minerals (like olivine and pyroxene) are typically more magnesium- and iron-rich, while later-formed minerals (like plagioclase and spinel) are more silica-rich due to depletion of Mg and Fe.

Other Notes

TBD

Snow Crystals, Kenneth Libbrecht

Snow Crystals: A Case Study of Spontaneous Structure Formation, Kenneth Libbrecht, 2022

This is Libbrecht’s magnum opus, at least on snow; this goes deep into the science. …and I love that he has ordered the references by date, so you can see the history of the science leading up to Libbrecht’s work.

C1: Snow Crystal Science

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The most basic shape of a snow crystal is a hexagonal prism — think a hex nut but without a hole in the middle. Made up of molecules, this prism shape tends to be ‘rougher’ at the angles of the hexagon, and the roughness offers more and more favorable opportunities for H₂O molecules to attach (this is in contrast to ‘flat’ or planar surfaces which do not offer such opportunities). Libbrecht refers to this as a growth instability, and it means that the prism tends to grow a projection from each angle leading to a six-pointed star and, as growth continues, a conventional snowflake shape.

The particular form of a snowflake is finely dependent on the humidity (degree of supersaturation) and temperature. The Nakaya diagram shows the general morphologies of snowflakes that form at particular temperatures/supersaturations. Snowflake shapes are diverse, and for practical purposes, unique, because the falling flake moves through regions of the cloud that differ in humidity and temperature. Nakaya liked to remark that snowflakes are “hieroglyphs from the sky,” because their forms describe the changing conditions through which they fell as they formed.

Generic diagram of how a snow crystal forms, and the Nakaya diagram that shows the morphology of snow crystals as a function of supersaturation and humidity. — Nakaya diagram of snow flake morphology

Mullins and Sekerka realized that growth instabilities are often associated with pattern forming systems, with solidification being a specific example (See 1964Mull). In particular, a dendritic branching process, now called the Mullins-Serka instability, occurs whenever diffusion limits the solidification of materials.
Studies of dendrite formation often involve succinonitril, because it is transparent and has a freezing point near room temperature. (See Glicksman 1976Gli.)
Eventually work on the Mullins-Serka instability grew into an area called solvability theory, which explains many of the defining characteristics of dendritic crystal growth.

A short tour of the book

C2: Ice Crystal Structure. Examines the properties of ice in equilibria, with special attention to “terrace step energies” in the basal and prism facets of ice crystals. Another factor called “surface premelting” is also discussed.
C3: Diffusion-Limited Growth. The formation of elaborately branched snow crystals results from the Mullins-Sekerka instability, which arises from the slow diffusion of water vapor molecules through air. Thus particle diffusion and surface attachment kinetics are the primary physical processes guiding snow crystal growth. This line of work also shows that heat diffusion and surface energies play relatively minor roles.
C4: Attachment Kinetics. This chapter describes the Suface Dependent Attachment Kinetics (SDAK), which along with Terrace Nucleation Theory and Terrace Step Energies can explain most of the morphological transitions seen in the Nakaya diagram.
C5: Computational Snow Crystals. This chapter discusses work on computational models of snow crystals — this is work in progress.
C6: Laboratory Snow Crystals. Examines various approaches to creating snow crystals in the lab.

I am going to pass on describing the other chapters… I believe that chapter 1-4 will cover most of what I’m interested in.

C2: Ice Crystal Structure

C3: Diffusion-Limited Growth

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C4: Attachment Kinetics

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C5: Computational Snow Crystals

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C6: Laboratory Snow Crystals

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C7: Simple Ice Prisms

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C8: Electric Ice Needles

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C9: Designer Snow Crystals

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C10: Natural Snowflakes

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C11: Snowflake Photography

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A Room of One’s Own, Virginia Woolf

Reading on my own, circa Fall 2024.

This book or extended essay is based on a lecture on Women and Literature that Woolf gave, or at least that is the framing of it in the book. She approaches the topic by explaining how she came to develop her thoughts about it:

“At any rate, when a subject is highly controversial–and any question about sex is that–one cannot hope to tell the truth. One can only show how one came to hold whatever opinion one does hold. One can only give one’s audience the chance of drawing their own conclusions as they observe the limitations, the prejudices, the idiosyncrasies of the speaker. Fiction here is likely to contain more truth than fact.”

She begins with an account of going to Oxbridge, and walking about the colleges. She notes that, being a woman, she is barred from walking on the grass, and is not welcome in the library. She has lovely descriptions of the landscape and colleges:

To the right and left, bushes of some sort, golden and crimson, glowed with the colour, even it seemed burnt with the heat, of fire. On the further bank the willows wept in perpetual lamentation, their hair about their shoulders. The river reflected whatever it chose of sky and bridge and burning tree, and when the undergraduate had oared his boat through the reflections they closed again, completely, as if he had never been.

And as we accompany her, she recounts her thought process. I love her metaphor (more extensive than the excerpt I quote) of thinking as fishing…

Thought — to call it by a prouder name than it deserved — had let its line down into the stream. It swayed, minute after minute, hither and thither among the reflections and the weeds, letting the water lift it and sink it, until–you know the little tug–the sudden conglomeration of an idea at the end of one’s line: and then the cautious hauling of it in, and the careful laying of it out?

Pausing in my account here, but passages that I like for various reasons follow:

“Lamb is one of the most congenial; one to whom one would have liked to say, ‘Tell me then how you wrote your essays?’ For his essays are superior even to Max Beerbohm’s, I thought, with all their perfection, because of that wild flash of imagination, that lightning crack of genius in the middle of them which leaves them flawed and imperfect, but starred with poetry.“

“Many were in cap and gown; some had tufts of fur on their shoulders; others were wheeled in bath-chairs; others, old though not past middle age, seemed creased and crushed into shapes so singular that one was reminded of those giant crabs and crayfish who heave with difficulty across the sand of an aquarium. “

“Fiction must stick to facts, and the truer the facts, the better the fiction — so we are told. “

“It was the time between the lights when colours undergo their intensification and purples and golds burn in window-panes like the beat of an excitable heart; when for some reason the beauty of the world revealed and yet soon to perish (here I pushed into the garden, for, unwisely, the door was left open and no beadles seemed about), the beauty of the world which is so soon to perish, has two edges, one of laughter, one of anguish, cutting the heart asunder. The gardens of Fernham lay before me.”

“I thought at last that it was time to roll up the crumpled skin of the day, with its arguments and its impressions and its anger and its laughter, and cast it into the hedge. A thousand stars were flashing across the blue wastes of the sky. One seemed alone with an inscrutable society.”

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EP#15: The Making of the American Essay*

*EP#15: The Making of the American Essay, John D. Agata (Graywolf Press, 2016)

Favorites are indicated by ** – there is only one: Blood Burning Moon.
* indicates those that I found something notable in, though I was not keen on them
(*) indicates something previouly read that I still like.
Frankly, I did not care for most of the essays (or, really, most were not essays, but presumably informed or influenced American essayists) in this volume.

This is the 15th volume CT and I have taken up in our essay reading project. Here we return to the type of book we began with — the broadly historical anthology. This differs from previous anthologies we’ve read in that it appears that the editor introduces each piece, something we’ve wished for in the past, especially when we’ve been mystified by why an essay was selected.

Later: Now that we’re farther into it, I’m a little less keen on it. A lot of the material in here are not actually essays: there are short stories, one sermon, a book chapter or two, and some very long pieces (Mark Twain’s A Letter from Earth), none of which strike me as essays. I had hoped for essays, or at least short essay-like pieces… and there are some, but quite a lot is other material. Although his initial introductions were pretty good at situating selections, as the book moves on the introductions are less about the selections, per se, and instead his sort of personal arc through American History. He is also quite fond of experimental work — work that, while it might have raised questions at the time, or contributed to discourse among the literati, is difficult to imagine anyone reading for pleasure or even enlightenment.

LS: Land Above the Trees: A Guide to American Alpine Tundra, Ann Zwinger & Beatrice E. Willard

February 2024…

This book was recommended in Kim Stanley Robinson’s The High Sierra: A Love Story, as a good guide to the ecology and botany of the Sierra Nevada (and the upper portions of other North American ranges). And, indeed, it is beautifully written with a narrative style in which the reader moves through landscapes with the authors, looking at this and that, in contrast to what I had expected would be more of a catalog or encyclopedic approach. The book is divided into two principle parts: part 1 examines elements of ‘above the trees’ ecosystems, like fellfields or krumholtz; part 2 looks at particular North American tundra ecosystems, with one chapter being on the Sierra Nevada.

LS*–The High Sierra: A Love Story, Kim Stanley Robinson

November 2023

The High Sierra: A Love Story, by Kim Stanely Robinson. 2022.

* I was reading this for other reasons, but nevertheless it fits well into my project to read essays that focus on landscape and natural history.

TL;DR: I love this book. But it is not for everyone. On the other hand, it is organized in such a way that readers interested in particular topics — geology, history, etc. – could skip through the book attending to one or a few themes that interest them. It has great pictures, too.

I’m a big fan of KSR, and think it likely that I’ve read everything he’s written, although it is possible that that omits a few early science fiction novels that were retroactively published after he became better known. I like the complex characters he develops, the intensely developed worlds he portrays, and especially his attention to geology, climate, economics, politics, and the role of large institutions – themes that are uncommon in much science fiction. Also unusual is that he sometimes ventures beyond the borders of SF, as with his novel Years of Rice and Salt, and especially with this book, which is multi-threaded work the interweaves memoir, geology, natural history and history.