Permanent Impermanence: or, How the Fuck Did That Fossilize?

It’s Weird Geology month here for the Accretionary Wedge.  Geology might not be quite as weird as quantum physics, but it’s got its moments.

There’s a great many weird things to choose from, but I’ll tell you what warps my mind: seeing things we normally think of as temporary preserved forever in stone.

Ripples in the Moenkopi Formation

Two hundred and forty million years ago, waves left ripples in soft sands and silts.  Currents worked and reworked these sediments, and you’d think that something so ephemeral would be wiped away long before the ancient mud flats and river beds turned to stone.  But this time, other sediments swept in and buried the ripples whole.  They lay there under their blanket for hundreds of millions of years, as ages passed, an orogeny lifted the plateau, time turned ancient muds to rock, and erosion wore the blanket away.  Now here we are, in the middle of a desert, looking at the echo of wetter days.

I’m sorry, but that’s just bloody weird.

Walk around Wupatki, and you’ll see ancient ripples exposed.

Ripples, Moenkopi Formation, Wupatki National Monument

They tell geologists all sorts of things about where they formed: whether by wind or water, what direction the wind blew or the water flowed, what an environment long vanished was like.  Just little ripples, most ordinary things in the world, suddenly extraordinary. 

And it gets weirder.

Mudcracks, unidentified sedimentary rocks, Richmond Beach, WA

Where I grew up, in northern Arizona, we got to see plenty of mud cracks.  And the thing about them was, they never lasted.  We’d have a torrential rain (in Arizona, when it rains, it usually pours).  Then it would get dry again (in Arizona, when it gets dry, it gets dry).  And then, a few days later, the hardened mud went back to being ordinary dirt again, worked over by wind, maybe a bit more water, and probably quite a variety of biological beings, all nice and soft and not a crack in sight.  They didn’t last.

So imagine my surprise when I learned that sometimes, if the mud cracks get covered by a nice layer of sand or silt, they can sometimes last forever.

Mud cracks, unidentified sedimentary rocks, Richmond Beach, WA

And if the sediment that covers the mud cracks is a bit different from the sediment the mud cracks formed in, you get some really wild contrasts.

Mud cracks are a dead giveaway that the place these sedimentary rocks formed in suffered from wet and dry cycles.  (I wish these told us more, but they’re in boulders ripped out of their context, so I haven’t got the slightest bloody clue what formation they’re from.  But if you ever make it down to Richmond Beach in Seattle, wander a bit down the beach toward the spot where the train tracks bend, and have yourself a look at the severely out-of-place mauve rocks shoring up the railway bed.)

And it gets weirder.  And wormier.

Burrow casts, Moenkopi Formation, Meteor Crater

These little delights are burrow casts.  Some enterprising animals wormed their way down into the sediments way back when the Moenkopi Formation didn’t realize what it was destined for.  Then something, maybe a flood, washed a bunch of mud and sand down into the poor dears’ homes, making a cast.  These had a slightly more exciting life than some in the formation.  Not only did they get elevated by thousands of feet over millions of years and turned to stone, but then, about fifty thousand years ago, a maclargehuge lump of iron and nickel fell out of space and tossed them around like a salad.  Exciting times.

But that’s not the mind-warping, worldview-changing, weirdest bloody thing I’ve ever seen.  This is:

Raindrops preserved in sediments, Almeria, Spain

Okay, so I haven’t seen that personally.  Chris Rowan has.  I’ve seen structures like these in various formations around Arizona without realizing what I was looking at.  Figured it was just a bit of weird weathering.  Well, in a way, it is.  But the weather happened millions of years ago, when rain fell on the smooth surface of a mud flat.

Raindrops.  Fossil fucking raindrops.  Can you think of anything more unlikely to survive millions of years and who knows what vagaries of erosion than a raindrop?  Such a delicate thing, such a tiny thing, a memory of a brief shower, so long ago, living to tell the tale.

Geology, my friends, is weird, and wonderful.

Living With Geology

John Van Hoesen of Geologic Musings in the Taconic Mountains asks a good question for this month’s Accretionary Wedge: “How much or what kind of ‘geology, have you incorporated into you home / living space?”

If I had my druthers, this house o’ mine would be slathered in stone.  Floors, counters, patio, all stone, of all sorts of varieties.  Sometimes, I stand in the aisles of Home Depot and just dream.  Travertine?  Slate?  Granite?  Gabbro?  Something more exotic?  I love it all.

However.  This is an apartment, and the complex might not take too kindly to me ripping various and sundry bits up and replacing them with a riot of rock.  So I’ve had to make do with hand samples.  They’re everywhere!

Mah not-so-grand entrance

If it’s flat, it’ll fit a rock.  That’s my philosophy.

Richmond Beach rocks

Here’s some lovely bits I collected from Richmond Beach, a sandstone sort of thing in a gorgeous mauve color.  You can see the old mudcracks.  I loves them!  There’s just something about an ordinary moment in time captured forever in stone that way.

Mah table

This is my constant companion, the table I sit by whilst writing.  On it, you’ll find some of my most-treasured treasures.  My spessartine garnet, my garnet schist, my carbonundum.  There’s some petrified wood, and odd unidentified bits I’ve picked up on walks along the area, including a chunk of what I’m nearly certain is marble.  Pretty pebbles, some beautiful pieces of local schist, all gathered from beaches.  A few polished stones from Arizona.  The hematite bracelet my mother got me for Christmas, which showed me she really had been listening to all my geobabble.  And a bit of limestone from Lord Hill.  Limestone’s rare around here, so I treasure it.

Zen garden.  Yes, I made the whole thing, including the building.  Look upon my works, ye mighty, and weep!

I love Zen gardens.  If I could have a yard, I’d have a Zen garden in it.  Have to content myself with Zen in miniature for the moment.  The dark rocks in it are bits of basalt picked up around my home in Flagstaff.  They’re from my childhood stomping grounds, so I treasure them.

Arizona Collection and extras

Here’s my rock collection from my Arizona trip.  You can read about the making of it in Arts and Cats I, II, and III, and a treatise on the finished product here.  Beside it, you’ll see some lovely bits of granite picked up in a Grand Coulee road cut.  Granite’s rare round there, so I treasure it.

You begin to see a theme, I’m sure.

On the other side, various bits and pieces picked up around beaches in the Olympics.  Just cuz.

Breakfast Bar

When I moved in here, I was a little overwhelmed by the white.  Decided early on I’d have to do something about that.  I began with some brown marble tiles from the Home Depot across the road, and rounded out with leftover bits of gabbro countertop that Lockwood kindly saved for me.  And atop those, some beauties gathered on adventures near Mount Rainier.

Richmond Beach collection

Okay, so I went a little nuts on the rock collecting at Richmond Beach.  Look, all sorts of awesome stuff had washed up on the beaches.  And there were endless delights in the railway embankment.  And when it comes to rocks, I haven’t got any willpower at all.

Oregon box

This is stuff I collected when out traveling with Lockwood last September.  I just haven’t got round to deciding where to put it yet.  But the dining table’s nearly empty….

Nightstand fountain

This is where it all began, this little fountain.  Nearly every rock on it is something special I bought: a bit of amethyst from Mount St. Helens, various baubles found in rock shops and gift shops around Seattle, Arizona, and other places.  Believe it or not, that tiny little fountain used to represent most of the rocks I owned.

Olympics collection
Closeup of the best sample

These were all collected during our trip to the Olympics.  Eventually, I’ll have them displayed properly.  They’ve got stories of subduction zones and orogenies to tell.  They’re the last thing I see before I go to sleep.  Well, other than my Lord of the Rings posters, anyway.  One of which has some really interesting fantasy geology in it…

Come back after this summer’s adventuring season, and I’m sure you’ll see plenty more.  Now you know why I’m afraid to ever move.  Between the books and the rocks, it’ll probably cost me a gajillion dollars.  But they’re worth it.

Desert Karst Oasis

Throw me your favorite geologic picture,” she says.  Like it’s that easy!  I can’t play favorites – every time I choose one, another one gets tears in its pixels and starts wailing, “Wait, what about me?”  And some of them chose to bow out of the Mardi Gras parade, claiming they weren’t colorful enough for such an event.  Whatever.

So we’ll do this.  We’ll cut to the chase and play a favorite – a favorite place, one of my favorite places in the world.  We’ll take a trek through the desert and come upon an oasis.

Montezuma Well, ambush shot by Cujo

Down around Camp Verde in Arizona, you’ll come across a picture-perfect karst terrain.  The old beds of lake-deposited limestone lay flat, dry and hot under the sun, carved into gullies and hills by wetter times.  In some places, sinkholes pit the scenery.  They’re lovely examples of the power of water and gravity together to sculpt the scenery.

Camp Verde got its name because a river runs through it, causing a line of green to conga through the hot, scrubby hills.  It was enough of a shock that explorers named it the Verde River, because it was very nearly the only green thing they’d seen for absolute miles.

Water’s rare and precious here.  You don’t expect deep, placid pools of it just lying about.  But drive through the dirt and dust, past lizards and rattlesnakes and blocks of ancient lake floor, and eventually, you’ll find yourself gazing down into a blue-green pond.  Long ago, water dissolved a large pocket in the limestone, and gravity collapsed the roof, leaving a hole deep enough to reach a perched groundwater table lying atop old mudstones.  Even in these drier times, springs still feed it to the tune of over a million gallons per day.

It’s here that the Spanish name for the ancient Pueblo peoples who lived in this area, Sinagua, becomes something of a misnomer.  They most certainly weren’t “without water” in this place. They had an abundance.  And they took full advantage, tucking houses and a granary into the cliffs along the sinkhole’s rim, more houses down by the swallet where the waters flow out into Beaver Creek, and building a canal along the base of the cliffs outside the sinkhole.

The old Sinagua canal

Walk down the cliffside here, and you’ll find yourself in an unexpected paradise.  Water cascades down a desert waterfall, flows along the old canal, and feeds tall sycamores and other trees and plants.  It’s shady, cool, and possibly the most peaceful place in Arizona.  And just look at all of that gorgeously-exposed geology!

I’ll have far more to say about it, plus a plethora of pictures, when we get to our Arizona geology series.  How’s that for a teaser, eh?

Now that you’ve had a nice rest at the water’s edge, on with the parade!

Oh, Schist! And Other Stories

Yes, it’s taken me this long to settle on an appropriate deskcrop for this month’s Accretionary Wedge.  In point of fact, I haven’t got any deskcrops.  I haven’t got a desk.  If I did have a desk, I wouldn’t be able to use it, as it would be covered in rocks, books, and the occasional knickknack. 

I have, however, got bookshelves, the bits of which that aren’t filled with books and knickknacks are covered in rocks.  I have also got tables, which are mostly covered in rocks.  Breakfast bar?  I hope you like stone-cold stones for meals, because that’s what’s on the bar.  Little half-wall in the entry way?  Home to more rocks.  And every single rock in this house has some sort of meaning.  Each and every one tells stories.  And they were all hollering “Me! ME! MEEE!” when I attempted to choose just one.  Worse than puppies, they are.

Ultimately, it came down to rocks from home.  And I couldn’t choose only one. 

Some of you may not know this about me, but I have an abiding fondness for schist.  I’m not sure why.  There’s just something about its foliation that I adore.  It may have a lot to do with the fact that it’s a) not volcanic, b) is metamorphic, and c) something I can identify with greater than 89% confidence despite all that.

It wasn’t always like that.  In fact, the first piece of schist I collected, I figured was just an unusual bit of volcanic rock.  It’s the dark one here in this photo:

It’s been with me since the early 2000s, when I grabbed it from the formerly-vacant lot behind my old apartment.  Needed nice, dark, interesting rocks for a mini-Zen garden I was building, didn’t I?  And there it stayed for years, nestled in white sand, and after I moved to Washington it lived in a Ziplock bag, awaiting a day when I had more space for Zen rock gardens.  Then I visited Arizona, picked up that lovely golden piece of mica schist that’s sitting beside it, removed it from its bag to add to the Arizona collection, and went, “Wait a damned minute… Oh, schist!” 

I believe it may even be a bit of Brahma schist.  Not sure.  I mean, it was sitting about 3,000 feet above where it should’ve been, so I know it’s a souvenir rock someone picked up and later discarded.  An anthro-erratic, if you will.  Could’ve come from anywhere.  But I love it anyway.

The mica schist beside it comes from the Mingus Mountains (no, people from Arizona don’t usually refer to them as the Black Hills, at least, not where I came from).  And that other bit there is a very nice little grossular garnet I picked up at the same rock shop.

But I promised you more than schist, and here’s a nice little bit you may enjoy from the same display:

That, my darlings, is a fragment of the nickel-iron meteorite that slammed into Northern Arizona about 50,000 years ago and left us with the enormous hole in the ground known as Barringer Meteor Crater.  They sell bits of it in the gift shop.  I was rather skeptical, so I grabbed a magnet with a bottle opener and a resin-encased scorpion and did a little field test.  Tink!  Yep, it’s magnetic, all right.  So I bought the bits, and a tube of rock flour.  That white powder is pulverized Kaibab limestone.  The meteor hit so hard that it turned major bits of strata right over and turned some into dust so fine that the frontier ladies used it as talcum powder.

So many rocks in that case.  So many stories.  But I shall conclude with this one:

That, my darlings, is a lovely bit of bornite, which I first knew as peacock rock.  Fascinated me as a kid.  I couldn’t care less if it was a copper ore back then – all I knew was, it’s pretty.  And I’d lost my piece.  So one of my major objectives when I went home for a visit was finding a nice specimen.  Where else to go but Gold King Mine, where I’d got my first?  If you ever get a chance, go to Jerome and visit Gold King Mine.  It’s a hoot, and they have lovely rocks and fossils in their shop.

Aside from the fond childhood memories, aside from teaching me more about the copper industry to fueled so much northern Arizona commerce, and aside from the fact it’s pretty, this deskcrop also broke the barriers between me and my newest brother.  You see, my parents had acquired a lavender-point Siamese, whom I hadn’t seen since he was a tiny kitten.  He didn’t remember me.  He wanted nothing to do with me.  I was a Very Scary Intrusion into his settled universe.  He ran from me whenever I came in – until the day I returned from Gold King Mine with a nice set of rocks and fossils.  I’d laid them out on the carpet while I sorted, labeled, and stowed for the journey home.

He inspected the fossils, creeping ever closer, and found the bornite as tasty as I do:

We have been friends ever since.  So, my darlings, remember this: geology not only provides us with knowledge, awe, wonder, and amusement, it can also facilitate better relationships with the important felids in your life.  Trust me, bonding happens.  Especially when you’re doing something fascinating, like trying to build a home for all those lovely samples:

Cats love deskcrops.  Spread the word!