Subduction. Todd Shimoda
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called the Shrine of Many Steps,” Mari said.
“Why is that?” I asked.
Mari gave me a little laugh.
On the first few steps, coins were scattered about. I guessed that most of the islanders couldn’t make it all the way up to the altar to the offering box, so they climbed as far as they could, and then tossed the coins after they’d prayed.
About halfway to the top was a small overgrown garden. The bonsai pines were no longer trained and had grown spindly. Moss had escaped its rock borders and spread like an unruly haircut.
I asked Mari if there was a priest at the shrine.
“No, the last one died several years ago. Sometimes one visits from another island, but there hasn’t been one since I’ve been here.”
We climbed the rest of the way and saw a few islanders working on a fallen post that supported the roof of one of the levels. Harada, as always, seemed to be in charge. They had tied a rope around the top of a pole and looped it though a hole in the other post. They started pulling in time with a rhythmic chant while Mari filmed.
The post tilted up slowly and I joined in, pushing it until it thudded into place. Harada tapped in a dowel to secure it. “There,” he announced, “that’ll hold it until the next shaker.”
I helped them shore up a few more of the posts. They didn’t shower me with appreciation, but they didn’t refuse my help either. When we finished, they even gave me a little bow of thanks.
The afternoon turned quickly to night. Mari walked toward a house—larger than the rest of those on the island—on the upside of the road. I followed her and we walked over the stone steps to the door. Inside, the old building smelled of earth and wood and charcoal, as all homes a hundred years ago must have smelled. Mari slipped off her shoes and stepped up to the straw mats that covered the floor. I did the same.
We walked slowly on the worn, yet comfortable mats. “Whose house is this?” I asked.
“It belonged to Furuta, the owner of one of the fishing fleets.”
Turning down a corridor, we came to an inner courtyard, open on the back side to the rocky slope of the island. The courtyard was small, barely room for three or four people to stand. A small spring bubbled invisibly, a gurgle of mineral-laced water flowing across the rock face and into a drain.
Mari stepped into the courtyard and lit a candle with a match. With the candle she lit several other candles placed around the courtyard. We sat on a raised floor that surrounded the courtyard on three sides. She watched the candlelight without talking. When I sat next to her, I felt calm for the first time in months.
we
will
Then the ground shook in an aftershock. The building creaked for two or three seconds, and I worried the candles would tip over and start the house on fire. But then just as quickly, all was quiet.
Mari moved slightly, a barely perceptible shift into me. We stayed in that position, without saying anything, only the sounds of the spring and a very distant sound of the ocean’s energy expending itself on the island’s rocks.
Then she leaned more, and slumped down, turning her face slightly so that her cheek was on my upper arm. She gave a little jerk, as if she was crying, and I shifted and pressed against her. She made a breathy whimper when I leaned toward her. She tilted her head to expose more of her face. Her head turned again, and as I was leaning in to kiss her, I heard a movement in the house.
I looked up and saw a person moving through the shadows. When the person disappeared around a dark corner, I got up slowly and went into the house. I didn’t see anyone, and went out front. Not too far away, toward the ocean, I heard a rock skitter down the slope. I followed the sound, and tried to see who it was.
But I didn’t see anyone.
6
In the clinic, I straightened up the mess and made a list of equipment, supplies, and medicine I needed to replace. The list was long, and I had no idea how to order the supplies or how long they would take to get to the island. I looked through the filing cabinet and found lengthy request forms, including completed ones yet to be filled. The government agencies responsible for public safety must be hoping the holdouts have quick natural deaths. They wouldn’t want them to be added to the earthquake death toll.
So that’s why they sent me to Marui-jima. To knock off a few old folks.
Aki came into the clinic and sat in one of the patient chairs. I asked him if he knew the magnitude of yesterday’s earthquake. As if I should know, he answered in an irritated voice, “A lower 5 on the Japanese Shindo, 6.2 on the Modified Mercalli.”
“You have a seismometer here?”
“A portable one that’s tied into the national network. Come on down to my workshop, and I’ll give you a tour. I think you’d find it interesting.”
I didn’t reply right away. Not that I didn’t think I would find it interesting, I simply wasn’t enthusiastic about the tour. Since I’d arrived, lethargy had swept over me, worsening each day. But boredom seemed a poor alternative, so I got up and followed Aki to his workshop.
The workshop was heavily reinforced on the outside diagonally with metal straps attached to the walls and roof. He explained the straps resisted an earthquake’s lateral sway. The door was padlocked in two places and a metal plate protected the lock and door handle.
“It’s the defunct fisherman’s cooperative,” Aki said, as he opened the locks and then the door. Inside the old building, Aki had also braced the interior walls with metal straps. A computer and monitor sat on a table against one wall. One of the several wires that trailed out of the back of the computer was connected to a squat black box with dials and switches. Much of the equipment looked similar to medical equipment: life support, vital sign monitors—equipment I didn’t have on the island.
As Aki explained the setup, I asked what he was researching. He handed me some sheets of paper stapled together. “It’s only the start of a rough draft.” I skimmed through it while he started his computer.
A Case Study of Subduction:
The Life and Death of Marui-Jima
Aki Ishikawa
Tokyo Metropolitan Division of Seismology and Earthquake Prediction
Introduction
Subduction is the flow of one of the earth’s tectonic plates under another. This process creates striking features on the earth, for instance, the Pacific deep-sea trenches, the deepest of which is the Mariana at a depth of nearly 11,000 meters. [check] … Subduction is also responsible for much [more precise?] of the earthquake and volcanic activity in the Pacific “Ring of Fire.”
The mechanism of subduction, however, is poorly understood. That the process occurs is undisputed scientific fact: evidence from the oldest areas of the seafloor shows the crust material to be a mere 170 million years old. This age compares with the earth estimated to be 4.2 billion years old, indicating that the plate material does not remain constant; rather, it is being recycled. [better term here?]
Approaching the mid-Pacific ridge, the material is much younger [find exact number], indicating the direction of the spread. When a plate descends below another, its material disintegrates and becomes molten. The molten material then spends millions of years [more precise?] mixing and flowing in the mantle’s convection loops, where it once again is pushed to the surface of the plates in the form of magma.
[add more on process here]
What remains to be proven is the driving force that causes subduction.