Rock Bottom (Em Hansen Mysteries)

by Sarah Andrews

  “That’s really cool.”

  “Yeah, it’s so complicated hearing one thing in school and another thing in church,” said Brendan.

  “I know what you mean. That’s why my mom is home-schooling me. Or rather, why she let my stepdad home-school me. Only he’s passed away now, so his brother is teaching me.” Out of the corner of my eye I saw her make a face.

  “Wow. My mom home-schooled me for a while, so I missed the part about how the earth has layers and stuff. So Em’s teaching me that stuff now. I’m supposed to write an independent study report about this river trip, because Dad pulled me out of school to come here.”

  “That’s pretty cool. So your mom was okay with you coming on this trip and being out of school and all?”

  “Well, not really, but we made a deal that I’d do church camp this summer and join her church if she let Dad have me for this. I usually spend the whole summer with Dad, but because of this I’ll have to do that.”

  This was the first I had heard of the deal Fritz had made to get custody of his son for the duration of this trip. My heart sank. I had hoped that Brendan’s presence indicated a stage of conciliation between the divorced partners in parenting, but I had been wrong.

  Fritz called to his son. “About ready to launch?” he asked. “Come on, Brendan! We’ve got to make some miles!”

  We loaded up and pushed off from the beach and hustled on down the river. Glenda Fittle had settled right in on the forward seat in Wink’s dory, her hair tucked up in a bun underneath a broad sun hat, holding herself with a prim upright posture and bearing. She reminded me of Katharine Hepburn in The African Queen.

  Mungo rowed close by us to get a beer from the drop bag. “Looks like he got himself a new training mare,” he mumbled.

  Fritz pantomimed covering Brendan’s tender ears, but the lad swatted his father’s hands away, saying, “I know what that means, Dad!”

  Mungo chuckled. “Well, let’s hope this one runs him harder, so he stays out of mischief.”

  The day began to unfold with the rhythm of the oars. The narrowed chasm of the inner gorge framed a cobalt blue sky, and at the foot of Hermit Trail I saw another pair of California condors rising into its updrafts.

  Brendan said, “I talked to the rangers about condors, and you know what they said? Everything we thought about how those birds mate for life isn’t necessarily so. They don’t even always raise their broods as a pair. They’ve got a trio of condors raising chicks here, a girl condor and two boys! And there’s another place where they’ve seen two girls and a guy!”

  “Ménage à trois,” I said.

  “What?”

  “It’s a French term, meaning—”

  Fritz swung an oar sharply across the surface of the water, splashing me. I shut up. I still had so much to learn about parenthood.

  It was a fine, sunny day, and though it was early enough in the year that the sun angle was still low and thus did not reach every corner of the Inner Gorge, bounced light caressed the fluted surfaces of the Vishnu Schist, which now rose like a strange, silvery temple above the riverbank. In places, the water had carved this ancient rock into fabulous arabesques, and here and there it was shot through with wide bands of pink granite. As our oars and the current carried us past, we pointed out our favorites, took photographs, and finally just stared quietly in awe.

  “This is very different rock from that stuff upriver,” Brendan said sagely.

  “Yes, it is,” I affirmed. “Schist is metamorphic rock. Remember when I was telling you about how the continents move around? And how they can rift apart or crash into each other? Well, all those tilted layers below the Great Unconformity got that way when the continents pulled apart, and here we see evidence of a collision.”

  Brendan opened his waterproof day bag and got out his notebook and pencil. “Draw me a picture of how it works, Em. Please?”

  I took his notebook and drew the classic diagram that showed the engine of the earth, with its three major layers—the superhot core, the soft-solid mantle, and the cooled crust—all sliced open like an apple so I could draw in arrows showing how heat flowed from the center out to space. “There are convection cells in the mantle, just like in boiling oatmeal. As heat rises here, the cooled bits descend. But here’s the key thing: This stuff that’s rising from the mantle is mostly dense minerals, heavy in iron and magnesium, so it’s just as happy to sink again as it cools, but there are also less dense minerals that tend to accumulate up at the surface, stuff that’s rich in aluminum and silicon. So as the dense stuff rises, it makes basalts, which are rich in iron and magnesium, and that flows out underwater and becomes ocean floor. You’re aware that the earth is about three-quarters ocean; well, under all that ocean are crustal plates made of basalt. Got that?”

  Brendan nodded, staring at my drawing.

  “Okay,” I said. “So what do you think happens to the less dense stuff?”

  “It stays at the surface?”

  “That’s what we see, yes. If you look at the continents, you’ll see that they, too, are big crustal plates, but they’re less dense, so they float like marshmallows in your cocoa.”

  Brendan smiled. “I like cocoa.”

  “So do I. And I like continental crust a whole lot.” I pointed toward the rocks of the Inner Gorge. “Here we have schists and granites. The granites are made of feldspars, quartz, and mica which are mostly silicon and aluminum. In fact, quartz is nothing but silicon.”

  “So why did it come up as granite instead of basalt?”

  “Brendan, you ask all the right questions. The deal is that it did not come all the way up from the mantle as granite. Instead, the lighter minerals slowly gather at the surface and accumulate on the ocean floors—silt and sand and dead critter bodies and what have you. Then, because those convection cells are sort of dragging the crustal plates around, the plates crash into each other. They slide apart where there’s a big boil of new basalt coming up—we call those mid-ocean ridges, and every once in a while they open up on land, like in the African Rift Valley—but then there are places like this.” I drew two convection cells rolling toward each other, pushing two crustal plates together. “What do you think happens there?”

  “They crash!”

  “Yes, they do, and if one of them is an ocean bottom plate it dives back down, because it’s heavier, or colder, and the continent slides up on top.” I added that to my drawing. “Then what happens?”

  “I … don’t know.”

  “Well, the ocean plate melts, see, because it’s going back downstairs where it’s so hot that it turns from rock back to soup.”

  “Really, Em: soup, marshmallows, cocoa? You’re ruining food for me.”

  “It’s just a handy metaphor. But the plate that goes downstairs is carrying a lot of crud that accumulated on it, right? All that silt and water and dead critters and so forth get squashed under unimaginable pressures.” I pointed at the schist that formed the canyon walls. “So that’s where this comes from. Think of a nice siltstone that’s been baked in the oven.”

  “There you go again, thinking of food.”

  Fritz chimed in. “It’s kind of amazing that she doesn’t weigh three hundred pounds, eh?”

  “Go ahead and mock me,” I said cheerily. “Okay now, the descending plate continues to go down, and all of that crud that’s riding on it has a cooler melting point than the basalt, so it melts first, and because it’s less dense, it wants to rise up through fractures that have formed from all that smashing and crunching. A great big blob of rock pudding comes up and up and up until it finds its point of neutral buoyancy, and it begins to cool. All of this takes a long time, and it cools slowly because it’s still down there several miles, and the rock above it is a good insulator. So it keeps finding its way into cracks in the crust above, and eventually some of it shoots up to the surface. Now, because the two plates are jammed together, they’ve made a thick spot in the crust, many miles thicker than it usually is, and it has
that hot juice squirting out of it. We call those volcanoes.”

  “Like Hawaii?”

  “No … Hawaii is sort of a special case. It’s made of basalt that comes straight up through the ocean floor from the mantle. Think instead of Japan, with Mount Fuji. This type of volcano spews lavas that are rich in silicon and aluminum. The name for that kind of lava is andesite, like the Andes Mountains, but don’t worry your head about the names, just know that this kind is full of quartz and it is connected down below to a big tub of hot stuff that’s cooling into a granite, which is the same thing as andesite only it cools slowly. Are we good?”

  Brendan gave me a thumbs-up.

  “So here’s the thing,” I said. “As the oatmeal continues to boil and these rafts of less dense crust form, they start to bang into each other and fuse together into bigger and bigger platforms.”

  “Like lint,” said Brendan. “Sorry, I couldn’t come up with a food metaphor.”

  I nodded. “Lint will do. Like lint accumulating in a lint trap, building up and building up. These microcontinents, that’s what we call them, get crunched together and bump up high, and the volcano parts on top are sticking up, so they erode down, dumping more silt and sand into the oceans that gets swept up into schists and melted again into blobs that become granites, continuing the cycle. Eventually we just get a bunch of granite that has rings of younger and younger microcontinents accreted around it.”

  “Like an onion.” Brendan gave me a cheesy grin.

  “Like an onion. And these older center parts are pretty stable, like marshmallows floating around—”

  “On the oatmeal.”

  “On the oatmeal. Yeah, and eventually these marshmallows get big enough that they start to slam together, too. So now you’ve got ocean floor crust banging against ocean floor crust and arguing over who’s going to go down, and continent banging continent and arguing over who’s going on top. Can you name a place where two continents are slamming together right now?”

  “No.”

  “Try Asia. India started out way south near Antarctica and has slammed into Asia, forming a big wrinkle in the crust that we call the Himalayan Range. If we had Google Earth on this raft I could show you how India is pushing so hard against Asia that it’s kind of extruding a bunch of it down through China, or at least that’s how it looks. But then there’s a third kind of collision, and that’s between an ocean floor plate and a continent.”

  “What happens then?”

  “The ocean floor goes down, no argument, and you get the schist and the andesitic volcanoes and the granite. An example is the Andes in South America. Or the Sierra Nevada in California, only that’s mostly done making volcanoes. The floor of the ocean was busy sliding underneath California, and it dragged a spreading center down under with it. For some reason the spreading center held together and it created a bulge that’s now underneath Nevada and western Utah. So remember when you mimed that accordion? You were right, that bulge of heat is stretching everything apart from Reno clear east to Salt Lake City, and as that happens there are blocks of land that stay high and form mountain ranges and others that drop down and form valleys.”

  Suddenly Brendan’s smile vanished. He mumbled something below our hearing.

  “What’s that?”

  “It’s something Mom’s pastor says when he’s talking about where the waters of Noah’s Flood went. Something about the valleys going down and the waters receding.”

  I was quiet for a moment, then said gently, “I’d like to just round out my dissertation on plate tectonics if I could. There’s one more kind of motion between crustal plates, and that’s when they just slide past each other. So that place where the ocean floor was sliding under California? Well, the plates are actually sliding over a curved surface, and the turbulence of the heat convection can make them turn, so what was a collision zone turned and became a very long fault line, called the San Andreas Fault.” I set down Brendan’s notebook. “I think that’s a lot for now, okay?”

  “Sure,” he said and put his book away.

  *

  Life goes on, whatever mental cares it throws us, and on a river trip, the water just keeps on flowing down the canyon, kicking up into big, splashy rooster-tail waves whenever it flows over something that creates drag. Crystal Rapid was the next big one. It was another choppy run of waves, but the sun was shining, Brendan’s ankle was improving, Fritz had him stay on shore while we scouted and tied the line to our raft in a way it could not possibly be tampered with, and all was good. Large as this water was, it seemed almost tame after hurrying through Sockdolager in search of a missing person, and I got my mantra back together and was actually beginning to enjoy myself again after the frights of that cold, windy day.

  We made camp and had a dinner of boiled potatoes and sausages and cleaned up afterward, and by and by I noticed that I hadn’t seen my husband or stepson for a little while. Figuring that they must have turned in early, I headed toward our tent, and sure enough as I walked up that path I could hear them talking. I was walking on soft sand, so they didn’t hear me coming. I was just bending to open the tent flap when I realized that they were having a pretty important talk, the kind that I really shouldn’t interrupt.

  “But you and Mom got divorced,” Brendan was saying. “Why, Dad? Why didn’t you stay together if you love her?”

  I froze, afraid to be caught overhearing these words, and because of that I was right there listening to his answer.

  “Of course I love your mother, son. I wouldn’t have married her if I didn’t love her. We couldn’t have made you if we didn’t love each other. It’s just … Well, there are many kinds of love, and sometimes you start out with one kind and it becomes another. Sometimes things don’t go the way you need them to go to keep it together.” He was quiet for a while, then added, “Even when folks get really mad at each other they can love each other just the same, but if that anger is covering up a great hurt, and you’d rather feel anger than pain…” He let it trail off, leaving a few things to his son’s imagination.

  I stared up at the stars, wishing I was most anywhere else, wishing simultaneously that Fritz would say something more.

  Brendan spoke. “Was it Mom’s church stuff? I mean, I know you don’t go to church, and … well…”

  “I don’t think it’s my place to talk about her religion. That’s a personal choice, guaranteed by the First Amendment of the U.S. Constitution and has to be respected, just so long as no one is getting hurt?”

  I winced, noting that his statement had ended as a question. Was Brendan getting hurt? Had his mother’s beliefs—or perhaps her use of them in postdivorce politics—edged into a place where psychic injury might occur? Where exactly along the line of parenting did imposition of doctrine become, at minimum, abuse of power?

  Brendan sighed. “She says that because I’m thirteen now I should join her church.”

  Should. The big conscience word. But should a mother’s conscience, however well intended, dictate her son’s beliefs?

  Fritz murmured, “You’ve got to follow your heart’s dictates there, son.”

  They were both quiet for a moment, and I was about to make a noise and head into the tent when Fritz suddenly spoke a flood of words very rapidly: “I don’t know what I would do in your shoes. At your age I couldn’t have made a decision like that to stand up in front of a whole congregation and say I believed X or Y. I’ve gone along with a lot of things, I suppose, but I’ve always tried to keep my mind open, because sometimes—oftentimes—I’m wrong about things, and it’s important to have room to catch a mistake and change it. People differ; that’s what politics are all about, and when they’re done well, politics are civil. Your mom and I try to stay civil, because most of all we both love you in a way that will never change, and it’s just not fair to let our differences mess up your life.”

  “Thanks, Dad.”

  I began to ease backward a few steps so I could make a noise a little farther away and
thus, literally, cover my tracks. But they were not yet done with this conversation.

  Brendan said, “You know that other group that’s been camping near us? The one with the girl with the guitar?”

  “Mm?”

  “Well, she says her stepdad, who was this famous TV preacher, said everyone who didn’t believe exactly as they did was going to burn in hell.” He laughed briefly, the nervous kind that’s supposed to say something’s funny when it really isn’t.

  “Wow.”

  “Do you think God is really some guy that burns people for things like that? I mean, what about all the kids who don’t have TVs, so they’ve never heard this rule? Do they get burned?”

  Fritz chuckled. “Now you’re talking about the difference between God and what a preacher thinks he’s heard.”

  “What do you mean?”

  “Well, maybe God’s will is like a radio. The transmitter might be just great, but if your receiver’s kind of weak you get a lot of static. When I’m flying an airplane I have to ask the air traffic controllers to repeat stuff all the time because I can’t always understand what they’ve saying.”

  Now Brendan laughed. “Is that why there are so many religions that are all different but all think they’ve got the straight poop?”

  “Could be.”

  “Well then, why do people follow preachers like that TV guy?”

  “I don’t know. I heard him once when I was flipping channels one morning, and he sounded kind of angry, but remember what I said about anger covering up hurt? The thing is, anger sounds more powerful than hurt, and it feels a whole lot more powerful than fear. It’s this energy that gets you moving, while pain and fear can freeze you to the spot. So maybe people like to follow anger because they think it makes them strong, or they perceive an angry preacher as being strong. Or they see that anger as powerful. Or they feel like they’ve screwed up somehow and that guy is like a big mean dad who says, ‘If you do this I’ll forgive you and make it all better.’ Or … I don’t know, maybe the people who like to listen to that don’t know how to make decisions and that angry preacher guy is willing to make them for them.”