Sistine Delta

Today’s imagery put me in mind of two hands reaching for one another:

What do you think? Shocking coincidence? Or a bit of a stretch?

Mineral phantasms?

Ice… serpentine… halite… What do they all have in common?

I’ve discussed mineral “ghosts” here before — really, those are only pseudomorphs, where one mineral’s chemistry becomes unstable due to a change in conditions, and then a new mineral forms in the same space. I’ve also brought up the issue of clasts of minerals which are unstable over the long term (ice).

Last night, at the final meeting of the Geological Society of Washington for the spring season, Bob Hazen of the Carnegie Institution of Washington gave the Bradley Lecture. Bob discussed his ideas about mineral evolution, and gave a compelling talk.

One of the key implications about thinking about minerals evolving over time is that new mineral species can evolve when conditions change and permit their growth, but so too can old mineral species go ‘extinct’ when conditions change and no longer promote their growth.

This got me thinking about that ice-clast breccia again (link above),  and how that would be interpreted by future geologists, assuming the ice itself has melted away. Consider the geologic record of a superwarm planet, where temperatures never dip low enough to form ice. Would we be imaginative enough to invoke ice as the cause of glacial landforms, of striations and deposits of till? How would we explain dropstones and ice wedges if ice were an “extinct” mineral on Earth?

And so after the talk was over, I went up to Bob and introduced myself and asked him if he could think of (or imagine) other minerals which could profoundly affect the geologic record, yet disappear after they have done their work. As we were talking, it occurred to me that halite in the form of salt domes could perturb the local stratigraphy, then the salt diapirs could rise up to the surface and be eroded (or re-dissolve into the ocean), leaving a piercing trail of destruction in their wake.

Bob came up with another one: serpentine at a subduction zone: hydrothermal alteration of oceanic crust produces serpentine, but then the serpentine is unstable when it gets subducted. It dehydrates (gives off water), and (poof!) there’s no more serpentine minerals. However, this dehydration is super duper important geologically: the addition of that water to the hot rocks of the subduction zone lowers the melting temperature of the rocks, and helps generate magma: the magma that rises to feed volcanic arcs. If we didn’t have oceanic crust to look at, would we have imagined serpentine beneath our convergent boundaries, a humble transformer of the world above?

Readers, I put the same question to you: Which minerals cause big effects, but then disappear? Who are the prime movers who flee the scene of the crime? These are minerals that aren’t just ghostly; they’re downright phantasmic!  I’ll be eager to read your suggestions, or hear your thoughts on the three I’ve noted here.

Flames and pillows, Route 55

I took a look at some interesting blobby structures in the Swift Run Formation last week, and walked readers through my logic in tentatively concluding that they were ball & pillow structures (soft sediment deformation), though overprinted by a pervasive (Alleghanian) cleavage. As we move west in the Appalachian mountain belt, the rocks are less cleaved: the strain is instead taken up in large anticlines and synclines with a few thrust faults thrown in. Though arched and fractured, the rocks’ fabrics remain pretty close to what they were at the time of deposition.

Fortunately, in the Valley & Ridge province along New Route 55 in West Virginia, you can see some sweet examples of (undeformed) ball & pillow in the Hampshire Formation (Devonian; part of the Acadian clastic wedge). Here’s a view looking up at the bottoms of some of these sandy sags (quarter for scale):

I like that partial weathering-out of the features into the third dimension…

To refresh your memory, ball & pillow forms when a heavy load of sand gets dumped (underwater) on top of a soft, squishy deposit of mud. The sand sags downward in broad “balls” (if you have a point locus of sinking) or “pillows” (if the sags have a linear axis to them). In between, the low-viscosity mud squirts up in cuspate “flame” structures. Check out this fine example (quarter for scale), found by GMU structure students Joe M. and Justin O. on the northern side of the road:

…And here we have the same photo, with the sand, mud, flames, and ball & pillow all labeled for you. The white arrows represent the downward sagging of the sand; the red arrows represent the upward squirting of the mud.

In some places, the pillows have weathered out. Here’s one (quarter for scale) that is now upside down on the grassy knoll beneath its source outcrop:

Note the thin laminae of mud clinging to its exterior, like a coat of paint!

Here’s a second sandstone pillow that has weathered out of the cliff and popped down onto the grassy slopes below. Obviously, the surface being photographed is a cross-section through the saggy pillow:

The “upper left” of this sample would have been the lowpoint of the sag if it were in situ on the outcrop. You can see the smooth margin on the left side, and the rougher zone on the right where it detached from the overlying part of the sandy layer. Let’s now zoom in on this box to see something really cool:

If we go deep here, we can see that the laminations of sand within the pillow show small Z-folds (and S-folds on the other side, though they’re not as obvious in the photograph) that are “parasitic” on the main fold. Here they are, highlighted (white arrows) and traced out (black lines):

The axes of these small-scale structures verge on the axis of the main fold, meaning that their axial planes (blue traces) “tip over” with increasing deformation towards parallelism with the main fold’s axial plane. We’ve seen similar things before. The axial planes play the same game as the cleavage plane. This is the first time I have ever observed such a structure associated with soft-sediment deformation, however.

Has anyone else ever seen S- or Z-folds associated with soft sediment deformation? It makes total sense to me that they would be there based on simple physics, but this was the first time I had ever seen it myself. I’d be curious to get a sense of how common or rare this might be.

A small gift

I have a student this semester, Diane, who is a flight attendant. Every weekend, she’s off to some cool European city with her husband, a pilot. Up until now, she’s been bringing me little gifts of beer from each trip. She drops 60 cents in Germany, and then that week I get to taste a new variety of ale or lager. Very, very cool!

This weekend, it was off to Rome, and she brought me back a piece of paper. This piece of paper had something written on it, though, something she thought I would appreciate because of my environmental concerns:

Pretty cool, eh? Despite his being a politician, I have a lot of respect for Gore for bringing the issue of climate change into the national consciousness. Unfortunately, because he’s a Democrat and a climate activist, the Republican response has been anti-Gore, and thus anti-climate science and anti-climate action. Hopefully Gore’s consciousness-raising outweighs the politicization of the issue he has wrought by advocating on its behalf.

Either way, the autograph is a great gift. Thanks, Diane!

(Did I mention she brought me a bottle of beer, too?)

Macrobeetle

A macro shot of a beetle (length ~11 mm) I saw on the wildlife-rich George Mason University structure trip two weekends ago…

Neat iridescence, eh? I love macro photography, especially of bugs.

3,2,1, Contact!

On my structure field trip just over a week ago, we found the contact between the Mesoproterozoic-aged Blue Ridge basement complex and the overlying Neoproterozoic Catoctin flood basalts (now metamorphosed to greenstone). This nonconformity can be found just west of the Appalachian Trail at the Little Stony Man parking area in Shenandoah National Park. Here’s four photos, with my left index finger for scale, in raw and annotated versions:

It’s not as glaringly obvious as some other unconformities profiled here, but it’s an important horizon in understanding the geologic history of the mid-Atlantic region.

In places, small inclusions of the basement complex may be found inside the base of the Catoctin Formation, a nice example of the principle of relative dating by inclusions. The basement rock must be older than the Catoctin if pieces of the basement have been broken off and enveloped in the Catoctin:

You’ll notice that the Swift Run Formation isn’t present at this location, though stratigraphically, it belongs between the basement and the Catoctin. The Swift Run is patchy and discontinuous, probably reflecting low-lying areas on the paleo-landscape, which paleo-hills poked up above the sediment-laden paleo-valleys, and were last to be smothered beneath the advancing flood basalts.

It’s a great pleasure to be able to find and “put your finger on” such a significant surface, such a gap in the geologic record. Given that the basement complex formed during the Grenvillian Orogeny (1.1-1.0 Ga), and the Catoctin erupted sometime before 565 Ma, there’s probably more than 400 million years of time that passed between the formation of the rock below my finger and the rock above it. Unconformity surfaces like this are geologic contacts which are emblematic of time passing, but going unrecorded in the geologic record. They are high-contrast reminders of how incomplete the geologic record is at any single location on the planet. They remind us to be humble in our interpretations. They remind us to strive for a multi-referenced correlation between different locations’ outcrops in order to get closer to the full story of our planet’s checkered past.

Heroes

For the twenty-fourth edition of the Accretionary Wedge, I selected “heroes” as the theme. For those of you new to the geoblogosphere, the Accretionary Wedge is a ~monthly geoblog “carnival,” wherein various and sundry geobloggers write posts on a common theme.

Broadly speaking, submissions to this edition fell into three categories: (1) professional heroes, (2) personal heroes, and (3) individuals who were both professional and personal heroes.

The ‘pros’:

Neil of Microecos was the first one to submit a tribute to three women paleontologists: Mary Anning, Annie Alexander, and Tilly Edinger. The three profiles he offers show conclusively that not all fossilists are old white men.

Ian Stimson of Hypo-theses also chose a woman as his hero: the woman who discovered in the inner core, Inge Lehmann. She made on of the most fundamental interpretations of the structure of our planet, using Ian’s favorite medium, seismic waveforms.

Above the core is the mantle, and plate tectonic theory suggested in the 1960s that the mantle might move around, dragging around lithospheric plates above. Chris Rowan of Highly Allochthonous reminds us that Arthur Holmes suggested something very similar in 1928. Chris explores Holmes’ ideas, style, and influence on geologic thinking at a critical time.

When the mantle partially melts, it makes basaltic magma. One spot where that liquid rock makes it to the surface is Hawaii, where Thomas Jaggar worked. Jess (a.k.a. ‘Tuff Cookie’) of the blog Magma Cum Laude says that the reason she finds Jaggar heroic is that he studied volcanoes in service to mankind. Jaggar valued the practical application of his ideas towards protecting people’s lives.

Chris M of Pools and Riffles wrote a post about one of his professional heroes, the pioneering fluvial geomorphologist Luna Leopold. Chris’s post dovetails nicely with a piece by Anne of Highly Allochthonous about Leopold’s collaborator Reds Wolman (see the “both” category below).

John Van Hoesen came out of the blogging deep-freeze with his thoughtful post about Louis Agassiz over at his rejuvenated blog Geological Musings in the Taconic Mountains. Agassiz, of course, is the reason that today we all think that the Pleistocene was a time of massive continental glaciation in the northern hemisphere. John’s understanding of his hometown is an Agassiz legacy.

Another John, this one the author of Karmasotra, opted for yet another John, John Wesley Powell, as his hero. Blogger John profiles Explorer John with a short biography and a sense of profound respect at how willingly Powell immersed himself in the unknown.

Finally, David Bressan of Cryology and Co. wrote an essay that discusses an important group of professionals: those who make us laugh. He discusses caricaturists and cartoonists, especially those who critiqued Victorian geologic thought.

The personal heroes:

Mel of Ripples In Sand came out of blogging semi-retirement to heap accolades on the geologically-aware individuals who forecast avalanche risk for skiers in the Rocky Mountain West.

I was the last person to submit an entry to this Wedge, and that was my tribute earlier today to Larry Wiseman, developmental biologist, artist, scholar, mentor, and connoisseur of life. His influence was instrumental in giving me my interests, enthusiasms, and priorities.

Larry was the one to put me onto the works of the author and philosopher (he hated being called a “nature writer”) Edward Abbey, and Abbey also happens to be the hero of Garry Hayes, a.k.a. Geotripper. Garry explores Abbey’s influential thinking and gorgeous prose, and relates it to issues like overpopulation and the climate crisis.

The “both” heroes:

Thinking along the same lines of Chris M (above), Anne Jefferson of Highly Allochthonous led the pack with a tribute to the fluvial geomorphologist Reds Wolman, who recently passed away. Reds taught Anne at Johns Hopkins when she was an undergraduate, and then she took up her doctoral study under an earlier Wolman PhD student, Gordon Grant, which meant that Reds became her “academic grandfather.” Anne’s tribute was penned before the Wedge was announced, but she followed up later with a supplementary tribute, including video of her hero.

‘Pascal,’ the author of Research at a Snail’s Pace, couldn’t choose a single hero, but some were clearly professional (Robert Bakker and Stephen Jay Gould) and others were clearly personal (parents and wife). See his many positive influences here.

Likewise, ‘Silver Fox’ of Looking for Detachment couldn’t pick just one, so she shared a collection of vignettes about why she finds Tanya Atwater and Tom Dibblee heroic, as well as her many advisors and mentors through life and geologic training.

Though the Sandglass‘s Michael Welland has both a professional and personal connection to his hero, thesis advisor Alan Smith. Michael relates the story of a day in the field, and how a thoughtful question from Alan revolutionized his thinking about field work.

Bill Normark was a marine geologist who produced work that was influential on the thinking of Brian Romans, author of Clastic Detritus. Brian describes how Bill’s work came off the printed page and into his life when Bill served on Brian’s PhD committee, and stimulated his interest in integrating modern sedimentation with the ancient sedimentological record. Apparently, he also made some tasty wine!

Some wine seems to be called for here: reviewing this stellar list of extraordinary individuals, I feel compelled to (virtually) pour each of you glass. Let’s raise this virtual wine aloft with a toast to these men and women who influenced our lives, our thinking, our science, and our goals.

May our heroes’ memories inspire us; may their legacies inspire others!
Long live the heroes; Cheers, everyone!

* < much clinking of glasses, shouts and huzzahs > *

Larry Wiseman is my hero

I have many heroes, but the one I would like to pay tribute to today is Larry Wiseman, my mentor through my undergraduate years at William & Mary and beyond. Now, Larry is a biologist, not a geologist — but he probably did more to frame my life’s work than any other individual.

At William & Mary, Larry was chair of the biology department, and taught the first semester intro course for bio majors: focused on cells, development, and genetics. (A second semester course, taught by Bruce Grant, would focus on organisms, ecology, and evolution.) Larry’s teaching style really resonated with me: it was very visual, full of analogies and clever turns of phrase. His test questions seemed perfectly attuned to my brain’s style of thinking: they tested not just content, but common sense. I liked this professor: he thought like me!

That first semester, I got involved with the Biology Club, ready to go off and help with campus litter pickups, and monitoring of beaches where piping plovers and least terns (two endangered species of birds) were nesting. I also started writing and cartooning for the Niche, the biology department newsletter. Larry supervised that operation too, and encouraged my wacky re-imagining of the Niche‘s mascots, two lab mice [one example here].

In my second semester as a freshman, Larry waived some pre-requisites and allowed me to take his senior-level Developmental Biology course. This too was an amazing educational experience. It was a wild course: we spent time thinking about the weird stuff that results when salamander limbs are rotated 180° and regrafted to their arms (3 arms sprout from the former elbow), about gastrulation (a fist pushing through a beach ball; the most important event in your life), and about apoptosis (pre-programmed cell death; the reason you have fingers instead of a big paddle). Larry wasn’t afraid to tackle the deeper meaning of developmental biology, either: he asked us at what point the soul emerged in a developing embryo. Was it at conception? Well, experiments show that a young embryo can be physically divided in two, and each half will go on to mature into a fully-formed individual. Do those two individuals have half a soul apiece, or do they share one soul? The reverse can also be seen: two embryos’ cells can merge, and they grow into one individual. Does that individual have two souls? I loved this stuff: I ate it up.

Eventually, my path led me to geology as a major, but Larry and I continued our mentor/mentee relationship. We would meet for coffee at Prince George Espresso about once a month, and talk life, academics, literature, and art. I credit Larry for my interest in the Belgian surrealist René Magritte, for instance. Another time, when I was mentioning my budding interest in geology, he recommended I try reading this guy named John McPhee. [Yes, a biologist pointed me to McPhee, not a geologist!] Perhaps most importantly, one day he took a sip of coffee and told me, “You have to read Desert Solitaire by Edward Abbey.” I checked it out of the Williamsburg Library and devoured it. It was the best book I had ever read, and it probably still is.

These coffeeshop conversations, as well as occasional walks we took in Colonial Williamsburg, were as important as any formal academic learning experience I had in college. Larry’s willingness to discuss big issues with me really helped sculpt my intellect. I am who I am in no small part due to those dialogues.

When it came time to graduate and move on, I wasn’t sure what I was going to do next. While some were pushing me towards graduate school, and others suggested job experience in geology, Larry said “I think you should get a used Subaru and buy an easel and some paints and move out to the southwest for three or four months and just make art!” I was astonished that a professor would suggest something so … nonacademic, so non-career-oriented. It made me trust him. This guy’s got a proper perspective, I thought.

A couple years after I had graduated (and yes, roamed around out west), I went back to visit Williamsburg, and happened to find Larry taking a gaggle of students out to lunch, facilitating similar discussions with them, nurturing the next generation of young minds. It made me happy to see.

Larry retired a few years back, to much fanfare. At that time, he had probably taught more William & Mary students than any other professor in the history of the College, and the students thought quite highly of him. They voted him faculty marshal, and threw a great party for him on the occasion of his last lecture. In his retirement, Larry and his wife Nancy bought a place in Fort Collins, Colorado, where they are pursuing a new project melding their interests in birds, native Americans, and art: Bird Rock Art. They are documenting the appearance of bird images in Indian petroglyphs and pictographs, and enjoying life on the Rocky Mountain Front. The summer before last, I stopped in and stayed a couple nights there on my way to and from Montana.

This man is responsible for guiding me through the most formative period in my intellectual life, and I’m eternally grateful for his time, attention, and wisdom. Because he helped me develop into who I am, Larry Wiseman is my hero.

Ball & pillow in cleaved Swift Run Formation?

On my structural geology field trip this past weekend, I made one major modification compared to last year’s iteration. I added a fifth detailed “field study area” at an outcrop of the Swift Run Formation, a Neoproterozoic sedimentary unit that is discontinuous in extent between the underlying Blue Ridge basement complex and overlying Catoctin Formation meta-basalts. A month ago, I didn’t know about this location, but I was introduced to it by Chuck Bailey on the Transect Trip last month. It’s a perfect complement to my structure students’ detailed examinations of the units above and below it, and the outcrop offers an embarrassment of rich structures to measure, both primary and secondary.

Here’s something I spent some time pondering: are there ball-&-pillow structures preserved in the Swift Run? We definitely see the ‘coarse-sand-dumped-on-mud’ set up that will lead to soft sediment deformation (sagging of heavy sand downward into squishy mud) under the right circumstances.

Okay, so with that in mind, take a look at this:

You’ll notice a clear contact here between dark, fine-grained mud (below) and lighter-colored arkose sand (above). The contact is irregular, so a sedimentologist unschooled in structure might start thinking about soft sediment deformation. But it’s not so simple as that: this rock is cleaved! The photo above is looking down parallel to the cleavage plane. Annotations:

The boundary between the two strata tends to get a bit scrambled at this interface, with an increasingly zig-zaggy trace as deformation proceeds. Now, let’s rotate the same sample by 90°, and check out the trace of the bedding on the cleavage plane itself:

Pretty smooth line, eh? Not nearly so “EKG-ish” as what we observed in the first photo. This suggests that the wigglyness we saw in the first photo is a structural overprint, and not a primary sedimentary feature. We can then breath a sigh of relief, and just use this cleavage plane outcrop to point out what a nice graded bedding contact looks like:

Here’s a second sample, as viewed on the edge where cleavage and bedding intersect. The little white dot is some kind of arthropod egg case; ignore it.

Whoa! significantly more up and down wiggles here to the contact between the two beds. Again, this could be a primary feature (soft sediment deformation), or it could be a structural overprint caused by the development of crenulation cleavage. I note how the bottom of the tan bed shows the large-amplitude wiggles, but the top does not. Now let’s turn this one 90° so we’re facing the cleavage face, and see what we see there:

Some annotations:

I would not expect a structural re-organization of the bedding trace as viewed on the plane of foliation, only 90° to it. So the fact that the second sample shows the wiggles continuing around all exposed faces suggests to me that it is indeed a primary feature, but the alignment of the most-vertical parts of the sags was accentuated by the development of cleavage, as seen on the first face. This interpretation is backed up by the observation that the basal part of the sandy unit (the coarsest part) varies not only in position, but also in thickness as you trace it out around all sides of the sample.

I’m not entirely satisfied with this interpretation though, because of the asymmetry and small-scale “parasitic” wiggles on each of the potential sand “pillows.” Furthermore, when I’ve seen true ball-&-pillow soft-sediment deformation structures in the field, the mud that squishes up is typically in a cuspate form, in stark contrast to the lobate blobs of sand that sink down. Here in this Swift Run sample’s foliation plane, the shape character of the ups appears to match the shape character of the downs. On the first view (looking parallel to the bedding/cleavage intersection), however, I suppose one could argue that the mud approximates a flame structure (cuspate) while the sand pillows look more lobate… but with the cleavage overprint, it sure isn’t super obvious.

Anyone else want to chime in on these two samples? Observations? Interpretations?

Earth Day

… So, today is:

… and not only that, it’s the 40^th anniversary of the first “Earth Day.” Shall we reflect? Yes, let’s shall.

My career as a geoscientist was largely inspired by desire to spend time outside, and that in turn was inspired by a lot of positive outdoor experiences as a child and young man. I feel at peace and satisfied when I am spending time in natural landscapes, most particularly mountainous landscapes.

The more time I spend thinking about the Earth system, its dynamics and  history, the more chagrined I become at my own species’ destructive habits. On the whole, I think it’s fair to say that we trash the planet wherever we go. We clear out naturally-occurring biota, and replace it with shelters and infrastructure for ourselves. We hike trails in the woods for recreation, and Hansel-like, mark our way with candy wrappers, tissues, and cigarette butts. The more I have learned what a non-human-influenced Earth system looks like, the more disgusted I get at the human fingerprint. My environmentalism is strongly influenced by my geologic awareness.

Of course, there are the bigger issues than litter and housing developments, like our agriculture-facilitated denudation of the landscape, our chemically-facilitated erosion of the ultraviolet-screening layer of our atmosphere, and the CO₂-facilitated warming of the planet’s average temperature. All of which have profound consequences not only for our neighbor species, but for ourselves. Without soil, ozone, or our coastal settlements, we’re increasingly screwed. We humans excel at shooting ourselves in the feet.

That point is the one that’s mostly likely to touch home with people: knowing our own selfishness, we environmentalists often ask our neighbors to adopt our views because it is in their own self-interest. We couch our activism in the language of harm to people, but I’ll admit that’s besides the point for me. I rank other species as inherently of value, in and of themselves, regardless of their benefit to humanity. I’ll admit that I have no scientific evidence to support this claim — it’s one of the few genuine “beliefs” that I hold. I believe other species deserve to exist, unmolested by us.

The elephant in the savanna is threatened by the elephant in the room: overpopulation of Homo sapiens. This morning, the world has 6.8 billion people on it, and tomorrow there will be even more. The rate of population growth is increasing at the same time that the resource consumption per individual is also increasing. The impact on the planet is astonishing. Life finds a way to adapt to our presence only in a general sense. The specifics, the particulars are being rubbed out. For ever individual pigeon or rat we gain, we lose a golden toad or an ivory-billed woodpecker. If the current rate of species extinction is perpetuated, then we are living through the start of the sixth great mass extinction of the Phanerozoic.

This broad view I take, where humans are not the pinnacle of anything, but something more akin to a cancer on the planet, is a grim one. When new medical treatments are announced, to the fanfare that they will extend human life, and prevent more people from dying, I wince a little. Longer lives are (probably) good for the ones living them, but a longer legacy of consumption makes things rougher for everyone and everything else. It’s the tragedy of the commons, written in lives.

The planet Earth would be a better place if there were fewer people on it. In no way do I advocate action to remove people from the planet — my sense of environmental duty does not trump my sense of ethics — but I can’t deny that I would prefer to live on a planet with only 1 billion people than the current crowd. This is a conundrum: I value the coherent functioning of the Earth system, but I also value individual human lives. I suppose the best thing you could do for the planet would be to kill yourself. Yet I find the experience of being alive so sweet: I couldn’t possibly give up that experience just for the sake of making the planet’s problems 1/6800000000^th better. Where does this leave me? Confused, perhaps. Hypocritical, maybe. It’s a tough spot to be in.

One thing that I’ve decided is that I don’t want to bring any more humans into the system. I have made an ethical decision that I can prevent a small piece of that overpopulation by refusing to procreate myself. I’m surrounded by people spawning huge numbers of kids, and I find it distasteful. My brother, for instance, has four children. Though I love each and every one of them, I can’t deny that I’m taken aback by my brother’s profligacy every time my nieces and nephews swarm around me.

Another thing I’ve decided is to try and make my time here a net positive, rather than a net negative. Yes, I consume, but then I try to use that consumption as fuel for the education of my planetary peers. I teach, I blog, I discuss. I’m not sure that this is a success, but I don’t know what else to do.

The modern Earth Day encourages us to “be green,” one of the shallowest and least thoughtful phrases ever to be willingly adopted by the environmental movement. Along with this single ill-defined word (“green,” the color of envy and seasickness), comes a marketing campaign which is focused more on consumption than on sustainability. “Green” is a buzzword, a fad. It’s time in the spotlight is fading, as far as I can tell. A deeper sense of ecology is needed, something that can’t be summed up by a single phrase or a single color. We live on a finite object, a lone oasis in an incomprehensibly enormous inhospitable void. It astonishes me that we slap a coat of “green” on our unsustainable existence and think that makes a damn bit of difference. Because the Earth is larger than individual humans, we have a rough time conceding that it is finite. But “big” and “infinite” are not synonyms; we cannot long act as if they are.

I find my outlook for the Earth’s biosphere to be a grim one. A robust biosphere is incompatible with human society’s resource-consuming, habitat-altering, Earth-system-perturbing ways. I wish I could say I was hopeful that we would get it figured out, but I’m not. We are neck-deep in evidence that our lifestyles are unsustainable, but we persist regardless. Our selfishness takes priority over our moral duty, and that seems to be human nature. As long as humans are part of the system, I can’t see how the average human impulse for comfort, security, and reproduction won’t continue to put our neighbor species at a profound disadvantage.

So here’s what I plan to do this Earth Day: I’m going to learn a bit more about the Earth, and I’m going to teach a bit more about the Earth, and I’ll appreciate the day as one among an almost infinite number of rotations of this fine orb as it orbits our fine star. I’m not going to be “green,” I’m going to encourage a fuller understanding of our role in the terrestrial flow of matter and energy.

I’ll feel lucky to be here today, and hope that I still feel that way 40 years from now.

How will you spend your day? How will you spend your time on this planet?