20 May 2019
I have a question for you. It’s about teaching geology.
Consider this photograph, by Tim Johnson, of an outcrop in the Buchan block of Scotland, near MacDuff:
Tim took the photo because he was impressed by the graded bedding and the “baby load casts.” And rightly so!
But there’s much more in that photo than just those features. It also shows percussion marks, and veins and joints (fractures), and it’s got a bit of colorful lichen on it too. And in addition to the coin (for scale), there’s modern sand in the lower right.
In short, there’s a lot to look at.
If a teacher were to be focused on teaching primary sedimentary structures such as graded bedding, and they wanted their students to see the “graded bedding” part of this image without risking getting distracted by the other details, would it be ethical to remove some of those other details using digital manipulation of the photo? (i.e., specifically by using Photoshop’s “cloning” tool)
Tim’s outcrop inspired me to try!
…For instance, what if we took away the percussion marks?
…What if we got rid of the veins?
…What if we got rid of the fractures?
…What if we did a “virtual pressure washing” and stripped away the lichens?
So the final result would be rather significantly less “real” than the original, but it may be more useful for teaching purposes, allowing students to focus on the graded bedding, and not be distracted by the other types of information/data/noise in the actual outcrop. Images modified in this way are not truly authentic, but they may make for easier learning, especially among novices who don’t know what to focus on. (I’m reminded of Werner Herzog’s “ecstatic truth“…)
Is it ethical to modify images in this way? In textbooks? In classes? (…on blog posts?)
I’d be curious to hear your thoughts about where the limits of this sort of digital manipulation lie.
Here are a few more examples I worked up, with the goal of stimulating discussion:
Relict cross-bedding in Weverton Formation quartzite, Thoroughfare Gap, Virginia:
Layered gabbro in the Stillwater Complex, Montana:
Fold in metagraywacke, Billy Goat Trail, Maryland:
Okay – let’s hear it: How do we most ethically utilize this powerful technique?
17 May 2019
This week, for Friday folds, I offer up some random folds that have passed my perceptual transom this week.
First up: In the new Netflix series Our Planet, in episode 7 (Fresh Water), an anticline/syncline pair makes a brief appearance as David Attenborough discusses glaciers as a reservoir for fresh water. Here is a screenshot:
I’m not sure where this is in the world: Greenland? Antarctica? Let me know in the comments for this blog post if you recognize this scene.
Cropped to zoom in on the fold, and minimize those glacial distractions:
Here, I’ve traced the bedding out, using red for the nearer of the two mountains, and yellow for the mountain that’s further away:
I made an animated GIF of the flyby, which imparts a better 3D sense of the outcrops:
The second fold I’d like to share comes from Highlights, a magazine for children that we subscribe to for the sake of my son: In this month’s issue’s science spread, they feature a fold from an Australian island under the title “How to Bend Rock,” though they don’t say which island.
Zooming in on the (annotated!!) fold:
I asked around on Twitter for other suggestions for “found folds,” and Jefferson Chang suggested the brake light pattern in the Chevy Bolt:
Sure, that works: It looks like an overturned asymmetric fold pair, perhaps a fault-bend fold.
Where have you found folds lately?
Have a terrific Friday and a rejuvenating weekend.
8 May 2019
I’ve just finishing reading Rising, by Elizabeth Rush. The book is about sea level rise (subtitle: Dispatches from the New American Shore) and it was a finalist for the 2019 Pulitzer Prize for general nonfiction. It’s an interesting book – lyrical and artful, with evocative phrases like “osprey’s creosote shadow.” Occasionally, these can go beyond clever/poetic turns of phrase, and can invoke other corners of literature, as when she describes a flood survivor “floating on a couch in her wine-dark living room,” – a shout out to Homer’s frequent use of the phrase “wine-dark sea” (whatever that means).
The book explores the biology and sociology of living in Pensacola, Miami, Jacobs Point, Rhode Island, Staten Island (New York), and Isle de Jean Charles, Louisiana, San Francisco Bay, as well as an interlude in an inland forest preserve in Oregon.
There are sections of the book that are essentially extended quotes from other people: testimonials that tell the person’s story without narrative filter. These feel kind of like “readings from the primary literature,” personal anecdotes told by those who were impacted by sea level rise. They are full of passion and fear, and very impactful emotionally. You feel the speaker’s pain, their sorrow. However, their parlance is at odds with Rush’s own lyricism, and alternating back and forth between them makes the reader compare the varied voices. It made me think of a scrapbook – a newspaper clipping here, and handwritten remembrance on the next page. The effect is to make Rising feel more like a collection than a cohesive through-going work of reportage.
The book features an extended discussion of sexual harassment from one of her sources, framed as part of a larger consideration of vulnerability. Rush is vulnerable as a woman reporter, conducting interviews in the field, and she draws parallels between that and the risk faced by people of limited means leaving in coastal wetlands. This is also invoked in a more extended analogy with the most vulnerable species leaving in increasingly flooded coastal wetlands. Our infrastructural footprint blocks them from migrating inland with the shore, so they feel the squeeze acutely and painfully. It’s not fair, but they have no good options.
Rising is a really personal book: In many places, Rush goes beyond mere reportage to describe her own emotional reaction to sea level rise. She reports on her own thoughts in the same way she reports on her interviews with coastal residents or scientists. She describes her dreams at length in several sections of the book. This is novel; the author’s midnight imaginings are outside the realm of typical nonfiction reporting. It’s simultaneously powerful and a bit uncomfortable in its intimacy. Is it legitimate to report on one’s own dreams in a book about sea level rise? I guess it is – not traditional source material, but powerful in the imagery it describes, the emotional state it draws the reader into. In sum, I’d say this is an interesting book from the perspective of considering the limits of traditional reporting and narration, and also a useful summary of where we are now with our submerging national coastlines.
3 May 2019
Darrel Cowan of the University of Washington steps up today with another contributed Friday fold:
I made this photo when I took my class deep into Monarch Canyon in Death Valley NP this March. From work by Stanford and others, the rock is probably medium-to high-grade metamorphosed Pahrump Group, now a well-foliated gneiss. If we consider the foliation, here vertical [I’m looking directly down], the XZ-plane of bulk strain, the little dikelet or leucosome is folded where normal to the foliation, and stretched where oblique–just as predicted.
Perfect structural fodder to start your Friday morning off right! Thanks, Darrel – as always!
1 May 2019
Peter Wohlleben is a forester, managing a forest in Germany. Over decades among the trees, he has had major insights into the “inner lives” of the trees, and uses this book to collate them and share them with a wider audience. The book opens with an anecdote: he walks by some moss-covered lumps in the forest, and peels up the moss to see what he expects will be “stones” underneath. He is surprised to find wood instead, and realizes that this ring of woody protuberances is actually a set of remnants of the outer diameter of an ancient tree, the middle having long since rotted away. On this observation, he estimates that the tree itself was felled centuries ago — but here’s the kicker: the living tissue of the tree survived, bearing the green signature of chlorophyll. Though this ancient giant had been felled generations ago, the stump had been kept alive ever since. It turns out that trees communicate and share food underground, via their root systems. This “dead” tree’s community of neighbors had sustained it for centuries. That’s amazing, and it’s just the start. Wohlleben leads his readers on a fascinating journey into the forest, viewing trees as thoughtful beings who live on an utterly different timescale from our own frenzied lives. The subtitle of the book is: “What they Feel, How they Communicate: Discoveries from a Secret World,” which gives you a sense of the content as well as the author’s attitude. What; they “feel?” Yes! Trees feel, and they can count, and they hurt, and they wait patiently. Never have I read something that successfully anthropomorphizes trees so well. I live in a forest, and I’m going to think about it more deeply and with more satisfaction and curiosity after assimilating Wohlleben’s ideas. Very interesting stuff; very well written. Recommended.
26 April 2019
This Friday, let’s hearken back seven weeks, when a similar Friday saw me and the ‘Streetcar to Subduction’ team in Marin Headlands, north of San Francisco. Black Sands Beach there is a great place for pillow basalts. You can see the knobby texture of the pillows on the far side of the beach, but today, let’s look at the big boulders in the foreground…
Let’s scoot over to the left a bit to that big boulder with the vertical stripes…
Close-up, these stripes reveal themselves to be upright and folded chert layers, with gazillions of tiny fractures perpendicular to the bedding planes:
The cherts here are gray, almost bluish-green, in stark contrast to the brick-red variety further to the east, near Kirby Cove and the Golden Gate Bridge.
On the underside of a cliff overhang at the west end of Black Sands Beach, there are more folded cherts of this gray color:
Happy Friday, all!
25 April 2019
I was very impressed with Steven Johnson’s The Invention of Air when I read it last summer. So recently, I decided to sample another of his books, this one a six-part microhistory about innovations that altered the course of human history. The six are: 1) cleanliness/hygiene (specifically in medicine and drinking water), 2) measurement of time, 3) glass (think lenses!), 4) understanding of light, 5) refrigeration, and 6) the recording and playback of sound.
The six part structure recalled for me another recent microhistory, A History of the World in Six Glasses, but Johnson’s book has an edge that makes it the better of the two. I think this is because he views these innovations in a deep context that leads enthusiastically in unexpected directions. He dubs these “hummingbird effects,” a shout-out to the well-established notion of a butterfly effect (wherein small perturbations cause large effects), with the distinction that with hummingbird effects, the chain of causality can be followed through logic and documentation. It’s knowable, in other words, unlike the chaos implied in the butterfly effect. The “hummingbird” moniker comes from the evolution of flowering plants during the Cretaceous, an innovation that is a classic example of co-evolution, between plants and insects. But once flowers were established as a thing on Earth (a nectar-rich thing), then it opened up a new niche for other organisms to tap into them as a resource. But to efficiently get nectar out of a flower, a bird needs to hover, and hummingbirds evolved to do this with a unique wing structure and flight pattern. That permutation of bird evolution wasn’t something that could have been foreseen from the perspective of the first primordial flowers of the late Mesozoic, but it did follow as an actual real-world consequence.
Similarly, Gutenberg’s invention of the printing press not only spread ideas and literacy, but it also showed a lot of people that they were farsighted, and would be able to read much more easily with curved pieces of glass perched just in front of their eyeballs. Gutenberg’s invention provided a shot in the arm to the lens-crafting industry, which itself precipitated numerous innovations as those lenses were manipulated to make distant things seem closer, or small things seem bigger. Johnson has a distinctive, polymathic way of viewing history that results in fascinating stories, well-organized and well-articulated. I found this a fascinating read (well, a fascinating listen, since I listened to the audiobook version on my commute – an act directly consequent to one of the six innovations explored in the book!).
These ideas were also the basis for a PBS series in 2014, which I had missed until writing this blog post. I’ll bet it would be comparably engaging.
24 April 2019
Here’s a fascinating book that combines biology and chemistry with human health and ecological consciousness. Venomous: How Earth’s Deadliest Creatures Mastered Biochemistry is Christie Wilcox’s masterful account of all things that inject toxins into other creatures. The book covers how those toxins are produced, how evolution has modified them, how they get injected and what happens then. Caterpillars and playpuses, jellyfish and ants and octopuses, sea urchins and shrews and tarsiers all inject venom, as well as spiders and snakes. Different organisms have different goals, and their venoms reflect that. Sometimes venoms appear similar because of descent from a common ancestor, and in some cases they have converged from quite disparate groups. Sometimes they are just one compound, but often (especially among organisms who use their venoms to get their dinners) they are a cocktail of different molecules. Wilcox does a great job writing up the most fascinating of stories, never tarrying too long on any one critter, and moves elegantly through adventure travel, scientific experimentation, pharmacological insights, and the pathological details of bites from these masters of biochemistry. Along the way, she debunks old ideas (like about Komodo dragons having foul spit rather than venom) and excites with tantalizing new notions (like bee venom as a potential cure for Lyme disease). A fascinating book, of just the right length. Thumbs up!
19 April 2019
Today we clamber down to Perles Beach. The rocks there are varied: serpentinite, blueschist, and meta-chert.
Here are some of the outcrops and boulders exposed there featuring folds:
The coolest thing about Perles Beach was these thoroughly recrystallized meta-cherts, with coarse reaction rims to be seen at the contact between the chert and shale protolith lithologies:
Unfortunately, I can’t speak to the identities of the various minerals involved, but if anyone is interested in querying these rocks more deeply, now you know where to find them!
17 April 2019
A whole book about aquarium fish? Yes, it’s possible, when the fish is the Asian arowana. The subtitle of Emily Voigt’s The Dragon Behind the Glass is “A True Story of Power, Obsession, and the World’s Most Coveted Fish.” The arowana is a fish that can be found in the Amazon (sometimes called the ‘water monkey’ there for its habit of jumping out of the water) but another species can be found in southeast Asia. This variety is green in most places, but golden varieties also exist, and it can be red in the heart of Borneo. These red arowana are seen as a status symbol in some Asian cultures, and an individual adult fish can sell for hundreds of thousands of dollars. The high price has precipitated several impacts. For one, it’s made dealing with the fish a high-stakes operation, with theft and even murder committed to access such a valuable commodity. It’s also depleted wild stocks of the fish, and nurtured a arowana-farming industry, resulting in a situation where the arowana is utterly endangered in the wild, but doing just fine in captivity (though unable to be traded internationally due to CITES regulations). The author, Emily Voigt, learns about the arowana on an endangered species bust in New York, but it leads her down a rabbit hole of learning, conversation, exploration, and obsession. As with The Feather Thief, which I reviewed Monday in this space, the subtitular ‘obsession’ could apply equally to the people Voigt describes, and to Voigt herself as the author. As she learns more, she becomes fixated on seeing an arowana in the wild, and makes multiple trips to Borneo to try and achieve that goal, stymied constantly by logistical matters. Along the way, she befriends a quirky fish-obsessed explorer, and learns of a new variety of arowana (with “batik” patterns on its scales) in an inaccessible jungle river in Myanmar. She tries to get to that one, too, carrying the mantle of scientific inquiry as her goal – seeking a type specimen for an ichthyologist to describe. Finally, she journeys to the Amazon basin, witnessing deforestation and dodging headhunters on her quest for a brief sighting of a wild arowana. I think the parts of the book I found most compelling were Voigt’s descriptions of the expeditions she made, trying tenaciously to access truly wild places, and how they are both simultaneously extraordinarily hard to visit and yet (once there) found to also already carry the heavy mark of humanity’s blighted touch. Combining economics, character studies, a history of the aquarist hobby culture, biology and ecology with a good dose of adventure travel, I found The Dragon Behind the Glass to be an enjoyable read.