14 January 2022

Book report

A collection of book reviews that may be of interest to readers of this blog:

Set in Stone: the Geology and Landscapes of Scotland, by Alan McKirdy

A well-illustrated introduction to the deep time history of Scotland’s landscape, controlled by the chain of myriad ancient happenings that produced and deformed rock of many kinds. Themes repeat, and there are one-off events that punctuate nature’s rhythms. The author has written for an audience of British non-specialists, but it would be a great place for an American professional geoscientist to start, to get an overview of Scotland’s geo-heritage. Having spent a month in Scotland several years ago, paying close attention to its geology, much of the book was review for me, but it did touch on several sites I missed – the Rhynie Chert, for instance. It would have been great for me to read before I went, but it was also a pleasant recap of the journey, complete with photographs of rock outcrops I recognize and think I know well. Scotland has such a deep, varied, and meaningful accumulation of rock types; If you’re not already a fan, this book will make you into one.

Passage, by Connie Willis

This novel, set in the 1990s, in a hospital in Colorado, examines what happens to the dying human brain when it experiences a “near death experience.” It’s an interesting premise, pursued in an interesting way, with multiple strands of plot coming together later in the story. However, it’s way too long. It’s at least 200 pages longer than I felt like it needed to be – 200 pages full of frenetic details which I suppose were offered to obscure and distract from key plot points – a school of red herrings, you might say – but I found it all quite tiresome to wade through. Honestly, I’m surprised I finished. That said, the early-’90s vibe is strong, with Blockbuster (the video store) and pagers (i.e. pre-cell phone remote communication devices) playing key roles: That part was an enjoyable foray into the world of my teenage years, but would doubtless limit the accessibility of the story for the younger generations. Willis paints a picture of the near death experience as a phenomenon that takes place entirely through biophysical means within the human brain, but gives treatment to both the sense that it’s more than that (that it transcends the physical world) is also explored both in terms of the internal qualitative experience but also its external promotion as proof of souls persisting independent of bodies after death.

The Anatomy of Fascism, by Robert O. Paxton

Well, here’s a book that I read not because I wanted to understand the past so much, but because I wanted to get a better grip on the present. A friend recommended it as the most methodical examination of the political/social phenomenon we call fascism; it’s written by a scholar at Columbia. As you might expect, Paxton explores Nazi Germany and the namesake movement in Italy headed by Mussolini, but there’s also a good amount of illumination gained by examining movements that didn’t quite make it to capturing any nation’s political system. Rather than a clear, punchy ideology-based definition of fascism, Paxton talks about aspects of fascist movements: characteristics and arcs of actions that tend to characterize them. Differences and exceptions prove these rules, and gradually a picture emerges of what it means to be fascist. It’s a process, triggered by trauma and stagnation, motivated by perceived emergencies, and aided and abetted by establishment conservative political actors. It nurtures a power structure which partially mimics official government responsibilities, and emphasizes violent punishment of “others.” Some countries go partway down the fascist path, but Germany and Italy are the only two examples that went all the way. A summary of the book’s way of recognizing fascism is (lifted from Wikipedia): “Fascism may be defined as a form of political behavior marked by obsessive preoccupation with community decline, humiliation, or victim-hood and by compensatory cults of unity, energy, and purity, in which a mass-based party of committed nationalist militants, working in uneasy but effective collaboration with traditional elites, abandons democratic liberties and pursues with redemptive violence and without ethical or legal restraints goals of internal cleansing and external expansion.” When I finished it, the question burning in my mind the whole time remained unanswered, so I googled it and yes, sure enough, with January 6th‘s attempted coup being the decisive event, Paxton is indeed convinced that Trump meets the criteria to be declared a fascist.

Below the Edge of Darkness: A Memoir of Exploring Light and Life in the Deep Sea, by Edith Widder

I remember Edie Widder’s talk to the Geological Society of Washington quite clearly: In discussing marine bioluminescence, she motivated interest by having all the lights in the auditorium extinguished, and then she brought out a bottle of seawater. When she gently shook it, dinoflagellates within pulsed boldly with blue-green light. It was magical. Widder has been pursuing various aspects of marine bioluminescence for her entire career, and this book is a very readable summary of her work. It begins with a moment of crisis in a submersible vessel, flashes back to an extreme health crisis in her youth, and then progresses through a career of adventure, scientific inquiry, and and the wonders of the deep dark sea. Widder’s main area of interest is the “midwater,” the largest portion of the ocean by volume, below the photic zone but above the bottom. It’s a place where most of the biology wants to feed at the surface (where phytoplankton capture energy each day), but find it too dangerous to actually be up there during the day, since predators can see them. So they feed at night, which necessitates a daily vertical migration between the nutrient-rich surface and the safe, inky midwater. It turns out that almost all of the critters use light as a defense, as headlights, as camouflage, or as a lure. She explores each of these uses with clever experiments, pushing the edge of what’s known about Earth’s largest biome. Really good: top notch, recommended.

Project Hail Mary, by Andy Weir

The author of breakout tour-de-force The Martian returns with his third novel. (The second was pretty weak: the moon thriller Artemis.) This one has a semi-silly initial premise, but after that, I think it’s quite good, pulling out the spirit of problem-solving from The Martian, and infusing the narrator with a similar sense of sarcasm and wry humor, but also mixing in a bit of the truly wondrous and weird. (“Weir(d),” see what I did there?) So, if you don’t want it spoiled, stop reading now. I’m going to reveal a key plot point that is unveiled in the first couple of chapters. [SPOILER ALERT] An astronomer discovers a strange line of light emanating from the sun, rising in an arc through space, and turning down again toward Venus. The sun begins to dim, and so a mission goes out to sample this strange line, discovering it is being emanated by a lifeform, a microbe. If you can suspend disbelief at this microbe going back and forth between the Sun and Venus, the rest of the novel is lots of fun. The protagonist of the novel, a high school science teacher, joins the effort to stop this microbe from eating our Sun and killing Earth. How? A survey of local stars reveals that they are all dimming too – all “infected” by what they soon call “astrophage.” Except one, Tau Ceti. If we can figure out what’s happening at that one, perhaps we can save Earth. So a mission is organized to go to Tau Ceti to suss it out and report back. This is the titular Project Hail Mary. But when the ship arrives, they find an alien race there doing exactly the same thing – trying to save their civilization, orbiting another of the dimming stars, 40 Eridani. First contact happens when two different planets are trying to figure out how to ward off extinction. Rather than a ‘war of the worlds,’ this leads to a fruitful collaboration, pairing scientific acumen from Earth with technological prowess from the aliens. [END SPOILERS] I really enjoyed it; and during some of the darkest days last semester, this book provided a digestible, delightful distraction. Lots of fun!

Disasterology: Dispatches from the Frontlines of the Climate Crisis, by Samantha Montano

This is a book everyone should read. Samantha Montano has written a terrific, readable summary of how and why we study disasters, and what it means for human society. It applies geology, oceanography, and in particular climate science to the practical questions of how best to live our lives in a changing world. Significant attention is given to New Orleans and Houston and coastal Maine, but many other locations are detailed too: places that have seen powerful natural events cause destruction that costs lives and dollars. Montano’s own biography helps link these case studies together as she describes her personal growth and key insights via lessons learned in to the disasters of the first two decades of the 21st century. COVID-19 hit right as she was going to press, but I found it particularly depressing to see how the lessons emergency managers (“disasterologists”) have learned from events like Hurricane Katrina once again failed to be applied to the nascent global pandemic. Montano’s perspective is fresh, vital, and clear-minded. Reading it, I found myself wishing she were the head of the Federal Emergency Management Agency (FEMA). Recommended.

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12 January 2022

Worlds in Shadow, by Patrick Nunn

Subtitled “Submerged Lands in Science, Memory, and Myth,” this well-conceived study examines the location of various lost lands on our planet, and the geological mechanisms of their drowning. Sea level rise, isostatic and sediment compaction induced subsidence, volcanism, tectonic slip, and good old fashioned erosion all have roles to play in taking places that were dry land and dunking them forever beneath the waves. In some of these places, humans lived prior to submergence. What did the people who lived there think of the situation? In some cases, durable oral histories preserved evidence of the submerged lands. Nunn presents a particularly compelling example from place names along the coast of Spencer Gulf, Australia, where the Aboriginal language has retained place names for certain stretches of what is today the coast, based on ancient namesakes that now lie six fathoms under. This is an example of “memory.” The particular strength of this volume lies in what Nunn does with other examples that are not quite so clear – with the keen eye of an anthropologist, he examines the mythology of different cultures, and what their cherished stories have to say about flooding and why it happened. There are no shortage of compelling examples to explore here, as you may be aware. In some cases, whole cities have been lost – though not Atlantis (I know you were wondering), which was conjured by Plato to elucidate a political point. All told, it was an enjoyable read. I was really impressed at the breadth of examples that Nunn describes – more than a hundred, I would guess, from the Philippines to the Arctic to the Mississippi Delta and the Amazon. You really feel like you’ve gotten a proper tour of the relevant sites when you close the back cover for the final time. The one stylistic quibble I would offer is that many paragraphs feature “sentences” that are not really full sentences in their grammatical structure. In other words, it’s written the way people often talk. I can take a bit of that when reading — indeed it often makes the writing powerful and punchy — but too much feels a little sloppy. There were a couple scientific factual errors I noticed: for instance at one point (p. 118), Nunn claims the Mediterranean has a low (rather than high) salinity. Elsewhere (p. 121), he repeats the widespread misunderstanding that continental crust sits atop a layer of oceanic crust, but these are not fatal flaws to the overall structure of the book. I enjoyed reading it, and found real power in its tripartite routes of inquiry into a fascinating subject.

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1 January 2022

Yard list 2021

It hasn’t been a good year for much, but I did get a lot of birding in. Traditionally, on new year’s day, I post my “yard list” from the previous year: a list of all the bird species I’ve personally observed from my yard.

At my new house, I now have a full calendar year of observations. You’ll recall I moved to Albemarle from Shenandoah halfway through the previous year, meaning I only had a half-year’s worth of Albemarle observations to report. Notably absent was the species that passed through during spring migration. Here, that issue is rectified, and I am pleased to present a bumper crop and a new “personal best” number.

In chronological order of species’ first appearance, this year I saw:

  1. Blue jay
  2. American crow
  3. Pileated woodpecker
  4. Northern mockingbird
  5. White-throated sparrow
  6. Carolina wren
  7. Mourning dove
  8. Golden-crowned kinglet
  9. Dark-eyed junco
  10. Carolina chickadee
  11. Pine siskin
  12. Northern cardinal
  13. Yellow-bellied sapsucker
  14. Eastern bluebird
  15. Northern flicker
  16. White-breasted nuthatch
  17. Turkey vulture
  18. Belted kingfisher
  19. Raven
  20. Canada geese
  21. Tufted titmouse
  22. American goldfinch
  23. Red-shouldered hawk
  24. Great blue heron
  25. American robin
  26. Black vulture
  27. Downy woodpecker
  28. Song sparrow
  29. Eastern phoebe
  30. Cedar waxwing
  31. Hermit thrush
  32. Common grackle
  33. Eastern screech owl
  34. Red-tailed hawk
  35. Barred owl
  36. Pine warbler
  37. Fish crow
  38. Red-winged blackbird
  39. Yellow-rumped warbler
  40. Wood duck
  41. Brown thrasher
  42. Brown-headed cowbird
  43. Chipping sparrow
  44. Eastern towhee
  45. Red-breasted nuthatch
  46. Green heron
  47. Field sparrow
  48. Northern harrier
  49. Tree swallow
  50. Ruby-crowned kinglet
  51. Purple finch
  52. Ruby-throated hummingbird
  53. Merlin
  54. Osprey
  55. European starling
  56. Wild turkey
  57. Broad-winged hawk
  58. Barn swallow
  59. Gray catbird
  60. Great crested flycatcher
  61. Blue-headed vireo
  62. Blue-gray gnatcatcher
  63. Worm-eating warbler
  64. Baltimore oriole
  65. Chimney swift
  66. Scarlet tanager
  67. Chestnut-sided warbler
  68. Blackpoll warbler
  69. Louisiana waterthrush
  70. Orchard oriole
  71. Red-eyed vireo
  72. Northern parula
  73. Indigo bunting
  74. Black-throated green warbler
  75. Bald eagle
  76. Eastern wood-pewee
  77. Spotted sandpiper
  78. Common yellowthroat
  79. American redstart
  80. Rose-breasted grosbeak
  81. Blue grosbeak
  82. Wood thrush
  83. Yellow-billed cuckoo
  84. Eastern kingbird
  85. Black-billed cuckoo
  86. Common nighthawk
  87. Golden eagle

A few thoughts about this list:

  1. It’s larger by ~20 species than even my best year at the Fort Valley house.
  2. I benefit here with more diverse habitat: more open country for grassland-preferring species (though I’m shocked I didn’t get a meadowlark or a kestrel) and a lake that draws in some waterfowl like the sandpiper, ducks, and herons. I’m also at lower elevation and on the seaward side of the Blue Ridge, which both facilitate a milder climate.
  3. Hummingbirds are NUTS here; it’s so delightful to watch their sipping and sparring each evening in the summer.
  4. I would not have thought I would ever see a golden eagle here, but I got clued in by watching the daily reports of the Rockfish Gap Hawk Watch during fall migration, where they document a healthy number of them. I only had one, and it flew over for only about 20 seconds, but I had my binoculars and got a solid look at it.
  5. The black-billed cuckoo (my first) was, sadly, a window-kill. This surprised me – we don’t get window-smacking birds nearly as much here as we did with the big plate glass windows at our Fort Valley house.
  6. I’ve been using the eBird app on my phone to keep regular lists; I find it motivates me to take walks: I’m not only getting exercise, I’m also birding and documenting what I see.
  7. I still have so much to learn about birding, and just took the step of joining a local birding club for the first time. Hopefully the skills I learn there will help me identify more species this coming year.

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30 December 2021

Footprints: In search of future fossils, by David Farrier

David Farrier is an English professor at the University of Edinburgh. He can write! He is interested in how humanity’s existence will be recorded in the geologic record – what will be our species’ most enduring traces? Footprints is a record of his explorations of that theme – in Scotland, China, Finland, and Australia, he explores key sites and meets with key people. From the to the nuclear waste repository at Onkalo to the Great Barrier Reef to the strata exposed at low tide near Dunbar, Farrier keenly pokes about and muses about our place in the grand sweep of geologic time. Informed by a systems-fluent environmental ethos, Farrier writes in a tone that is calm and contemplative, but with a bit of whimsey thrown in. We’ve long known that our lives our ephemeral phenomena; Farrier extends this to our species and imagines the post-human world: the aspects of its condition that we have wrought, and those that have occurred despite our efforts. It’s a fascinating mix, adequately explored and well described.

One of the neatest chapters was a thought exercise about the future of a plastic bottle. It reminded me favorably of the chapter in Michael Welland’s Sand wherein he describes the deep-time journey of a grain of sand. It would make a great stand-alone reading assignment for an undergraduate class in environmental geology or oceanography.

There were two small factual errors in the edition I read, but nothing that critically undermines the book’s mission. I’ve emailed the author about them, so hopefully they will be fixed in future editions.

Geologic time is lucky to have enticed Farrier’s attention. He writes well about it, and I hope it’s not too much to hope for more geo-focused volumes from his pen in the years to come.

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12 November 2021

Friday fold: Raven’s Ridge

Happy Friday, all! Two shots today from my friend Joe up in Vermont. He sends these from the Champlain Valley, at a place called Raven’s Ridge.

It looks like an alternating series of sandstones and shales, arched into an anticline, perhaps during the Acadian Orogeny (??). According to the Nature Conservancy’s website, porcupines live in this anticline, which is called “The Oven.” Looks like most of the strata around there are Cambrian in age. If anyone knows more, please clue me in!

A lovely outcrop – thanks for sharing, Joe!

If you have a fold to share for next Friday, beam me a note at [email protected]

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6 November 2021

Revisiting Tinker Creek

While my son takes banjo lessons downtown, I stroll Charlottesville’s walking mall and browse the bookstores. Last week, I dropped $40 at one of the used-book stores, walking away with an armful of volumes. Most were intended for my son (a voracious reader in addition to being banjo-philic), but on the shelf I also saw a trade paperback copy of Pilgrim at Tinker Creek, by Annie Dillard (1974), a book without which I think no naturalist’s library in Virginia is complete. I’ve read it before, but I love it dearly — so I bought it.

Winner of the Pulitzer Prize for general nonfiction in 1975, Pilgrim is a work of wonder at nature and the fact of our existence. Like no other book I’m aware of, it captures the giddiness of the transcendent experience. Dillard has a talent for putting herself in natural settings and being receptive to whatever is offered up.  “I cannot cause light,” she writes. “The most I can do is try to put myself in the path of its beam.” Where that beam shines, it illuminates, and by forming shadows it its absence, the light causes her myriad subjects to pop into relief. Once lit, a landscape or organism is seen in a new way. It means something different by virtue of Dillard’s eye catching those reflections and refractions, by virtue of the way those photons stimulate her mind.

Her language is equally adept at describing the natural world in her Roanoke Valley home and describing her own personal reactions to being out there, receptive to nature’s clockwork and chaos. I think that, at least in this one book, she achieves the most resonant articulation of what it is to be astonished by one’s experiences perceiving natural phenomena. “I had been my whole life a bell, and never knew it until at that moment I was lifted and struck.” It’s a beautiful book that drifts in and out of what you might call ‘nature writing’ and what you might call poetry. There is a substantial infusion of Biblical analogy and mythology, which isn’t my cup of tea, but does frame Dillard’s perspective as distinctive. Her evocations of God serve to emphasize the intense profundity of her experience, and I can relate to that, even if my own experiences lack the spice of belief.

This is my fourth time reading Pilgrim at Tinker Creek, and it still gives me a frisson of astonishment when I read it. It is such a good book.

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25 June 2021

Friday fold: The Blue Ridge Tunnel

On Wednesday of this week, I went for the first time to the newly-opened-to-the-public Blue Ridge Tunnel, a county park in Nelson and Augusta counties, Virginia.

Built in the 1850s to serve as a railway tunnel, it provides a unique perspective on the geology of the Blue Ridge.  The western side is largely bricked-over, but in the middle, about at the Nelson/Augusta County Line, there are a series of extraordinary exposures that Chuck Bailey has dubbed “The Hall of Boudins:

The rocks here are all Catoctin Formation, a Neoproterozoic series of rift-related lava flows and intercalated sedimentary rocks that were metamorphosed during late Paleozoic mountain-building. In the photo above, you can see buff-colored Catoctin greenstone (metamorphosed basalt) with a pronounced east-dipping foliation. Within it are lozenges of green-colored metasandstone. Those pod-shaped blobs are green because they host a lot of epidote in them (a metamorphic mineral that is frequently found in areas of low-grade metamorphism under wet conditions). They are not in their original depositional orientation or shape, however; they have been boudinaged (stretched into asymmetric taffylike segments) as a result of tectonic stresses that shoved Blue Ridge rocks up from the east toward the west.

The kinematics of those same Alleghanian forces can be inferred from not only the asymmetric boudinage, but also asymmetric folds within the same rocks. These folds can be mapped out with careful measurements of bedding and foliation orientations, but sometimes they are more plain, as with this hinge:

There’s also a more subtle Z-fold on the left, above my fingers. The photo also shows well the difference in color between fresh Catoctin (dark) and weathered Catoctin (buff tan).

This is a really cool location to have as a local geologic resource; I look forward to my next visit.

If you visit, first download a geologic guide to the Blue Ridge Tunnel (PDF) by Katie Lang and Chuck Bailey. It calls attention to several subtle things that I missed on my visit this week.

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16 June 2021

Book report

A few more books I’ve read recently….

Why Fish Don’t Exist, by Lulu Miller

An interesting volume by NPR’s Lulu Miller – a philosophical biography of the first president of Stanford University, the fish biologist David Starr Jordan, mainly, but also an autobiography of key moments in Miller’s own life. At first, she looks to Jordan for inspiration – how does this man keep going after a series of awful setbacks to his work? Deaths in his family, the 1906 San Francisco earthquake shattering his jars of preserved holotype fish specimens, etc. Somehow, he takes a lickin’ but keeps on tickin’… What’s the man’s secret to his success? But then it gets darker – Miller lays out the case that Jordan may have engaged in the murder of a key person who might have otherwise undermined his meteoric success. She also shows him to be a virulent proponent of eugenics, promoting the “improvement” of the human gene pool by forced sterilization of individuals he deemed “unfit,” presaging the Nazi’s genocidal campaign by decades. Miller’s journey of exploring Jordan’s legacy takes her from DC to Chicago, and Charlottesville and Lynchburg here in Virginia. Her personal story takes twists and turns but ultimately she finds peace, joining the two narratives with an assessment of what is real in life.

Owls of the Eastern Ice, by Jonathan C. Slaght

An account of a multiyear field research project to document the biology of Blakiston’s fish owl, the world’s largest owl, which lives in eastern Siberia and eats fish from radon-warmed rivers all winter long. There are plenty of mishaps, adventures, and weirdos in the story, which blends a classic travelogue with detailed ecology that will be of interest to birders and biophiles. One of the themes that emerged is the essential value of international collaborations between that very, very small subset of the population who cares passionately about preserving rare and obscure species. Slaght has a collaborator in Siberia who helps make great things happen and smooths over logistical snafus. Another theme that emerges is how incredibly difficult it is to gain basic biological information about species living in such tangled, buggy, wild terrain. This volume documents years and years of difficult work, with precious insights lost when bold ventures fail. A look at the bleeding edge of conservation ornithology, in other words. Very interesting and fun.

Metazoa, by Peter Godfrey-Smith

Where did consciousness come from? In this follow-up to his awesome volume Other Minds, Godfrey-Smith explores key innovations within the animal branch of the great Tree of Life. The author is a philosopher who is an avid scuba diver, and many of the explorations of experimental work are prefaced by anecdotes about creatures he has encountered in the waters around Australia. It’s an exceptionally well-written volume, where complicated and nebulous ideas are presented firmly and tangibly. In fact, if you’re looking for an almost-perfect exemplar of science nonfiction, I’d offer this volume up as “Exhibit A.” Godfrey-Smith makes a strong case that consciousness is widespread though gradational throughout the animal kingdom, and that mind is inherently a function of body. A fascinating pair of tangents toward the end of the book explore the implications of this perspective for artificial intelligence and for the question of what is ethical when it comes to our treatment of other species. Top notch: fascinating & highly recommended.

American Manifesto, by Bob Garfield

Written during the third and final years of the Trump administration (before COVID), this is On The Media’s co-host’s perspective on the American political situation – the degradation of discourse, the polarization of media, the growing lack of willingness to accept experts’ expertise. It’s a dismaying read – the previous four years were a sincerely rough time for my country, and we’re not out of the woods yet. In fact, recent events in Congress suggest the worst may be yet to come, with Trump merely a harbinger of a fatal erosion of our foundational democratic institutions. Bob Garfield is a clever person, and his wit is mostly a joy to behold, striking incisively at a horrible situation with humor and intellect. Occasionally he goes too far, and his analogies make me cringe, but 95% of the time, the writing in American Manifesto made me feel he is a kindred spirit, deeply distressed at the way we’ve come to run our society. Thought-provoking, and perhaps a bit more depressing than Garfield intended it to be.

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14 June 2021

What the Eyes Don’t See, by Mona Hanna-Attisha

I just finished an excellent insider account of the Flint water crisis, written by the pediatrician who brought it to the attention of the wider world.  Mona Hanna-Attisha practices medicine in Flint, has a background in environmental activism, and happened to be good friends with a specialist in the management of municipal water systems. An evening’s conversation between Dr. Mona (her preferred name) and her friend ends up launching her on a path to stop the poisoning of an entire city’s worth of children. She’s the right person in the right place at such a very, very wrong time. The story she tells has many levels – it’s medical and about public health, but it’s a guide to effective strategizing when faced with official government recalcitrance and obfuscation and children’s lives are on the line. Dr. Mona walks us through her decision-making and coalition-building, and the power of key individuals to solve problems or make them worse. It’s also a deeply personal story, where the background saga of the Hanna family’s emigration from Iraq to Michigan is central and relevant. This isn’t just a story of environmental chemistry; it’s a story of unions and past public health crusaders; a story of societal trends and tensions; a story of the power of a key individual to make the world a better place despite harrowing attacks by penny-pinching, racist agents of the status quo. Though written and published prior to the coronavirus pandemic, the book is timely and critical for considering our current spate of public-health challenges, and actions that will tamp down future suffering or exacerbate it. What The Eyes Don’t See is very well written, and the audiobook is perfectly read aloud by the author. Top-notch, worthy of widespread acclaim, and worth your time and attention.

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11 June 2021

Friday fold: inadvertent kink fold analogue model

It’s Friday!

Adam Forte, a geology professor at LSU, posted this image yesterday on Twitter:

It’s a box of sheets of newsprint, stored vertically and ignored for a while, now rotated 90° so we’re looking at a cross-sectional view. To me, this is an excellent example of a physical analogue modelling experiment (albeit inadvertent) that demonstrates the process by which kink folds form. The key parameters to get this distinctive style of folding is (1) a highly mechanically layered material, (2) a substantial confining pressure, and (3) a dominant stress direction is parallel to the orientation of that layering, or close to it. In the case of Adam’s box of paper, the layering comes from the discontinuities between the sheets, the confining pressure comes from the box, and gravity’s pull was the principal stress direction (σ1). In geological examples that I have celebrated on this blog, the layering is usually sedimentary bedding or metamorphic foliation, and compressive tectonic stress is the cause of the kinking, while being buried deep in the crust provides the requisite confining pressure. Compare what you see above to these examples:

Other kink folds, from previous posts:

Dalradian schists, Walls Boundary Fault, Shetland

Harpers Formation phyllite, Harpers Ferry, West Virginia

Dalradian schists, Arran, Scotland

Somewhere else in Arran (not my photo)

Metagraywacke, Billy Goat Trail, Maryland

Playa limestones, Basin & Range

Catoctin Formation greenschist, Thoroughfare Gap, Virginia

Unknown source – kinked phyllite from the GMU teaching collection

Sample on display at Tennessee Tech

St. Ninian’s Isle, Shetland

And one more from Shetland, again of the Dalradian schists adjacent to the Walls Boundary Fault, since they provide the closest visual match to the paper in Adam’s box, but this time as a stone in a rock wall:

Peace be upon you. Enjoy the weekend. Stretch those kinks out, and get some rest.

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