My first trip out of Cusco starts at 5:15 with a quick breakfast of eggs and coffee. Before we get on the road, we stop at the container—a rented shipping crate in a vacant field that Lara uses to store all the supplies for each site. Since the seismometers haven’t arrived yet, we’re getting the ground ready for them by digging holes for the plastic barrels that keep the machines waterproof.
We’ve hired three drivers, two for the half of the group that includes me, Lara, Professor Victor Aguilar from the Universidad National de San Agustin, and Christine Worthington, one of Lara’s graduate students from UNC. The other group—Jenny Hanna, a student of Maureen’s, Mike, and Astrid Martinez, a friend of Lara’s who is here to translate and help out—has a van to themselves.
We load four types of shovels, two types of cement, and five barrels into our trucks. After clearing the edges of Cusco, we start to climb over a high pass. I can see snow covered mountains in the distance, and alpaca and sheep farms line the highway. A woman and two children come out of a stone house to beg, lowering cupped hands towards the road.
This particular road used to be known as the worst in Peru, but it is currently under construction, and large parts of it are now paved. We arrive at a possible site much sooner than expected, and a family agrees to let us put a station in their chicken yard.
There are boulders everywhere, and the man who owns the property tells us that an avalanche deposited them all over his part of the valley. The rocks are not only on the ground, but they are also underneath it, and digging the hole for the barrel proves somewhat challenging. Lara, Christine, and I are all ready to work, but the drivers, Victor, and the owner are reluctant to let us women dig. Victor smiles and points at the men. “Hombres machos,” he says.
Lara ignores them and grabs a rock breaker, earning herself the title of “trabajera.” Some of the rocks are probably 200 lbs, so Lara strikes a compromise. “Les hombres les rockas, les mujeres la terra.” This seems to satisfy everyone, and in between rocks, Christine and I start digging.
When we’re done, we mix concrete and pour it into the hole. Then we put the barrel in, level it, and add more self-leveling grout on the inside. The concrete on the outside keeps the barrel stable, and the grout keeps the inside level as well. The leveling is to insure that when the seismometer is placed inside the barrel, it will be able to correctly read which seismic waves are coming vertically through the mantle, and which are coming horizontally through the crust.
After we get the site prepared, I climb in the car with Victor and he hands me a Spanish-English dictionary. As the landscape outside the car changes, I learn enough to ask him what kinds of trees are in the jungle on either side of us. He tells me there are plantain trees and coconut palms.
The road also winds along a river, and the construction has created a lot of loose soil which miners downstream pan for gold. That night, we stay in a mining town that could have come straight out of the American west circa 1860. The only grown women in evidence run hotels, laundries, and restaurants. The main drag is studded with pay telephones and gold buyers for those who strike it rich.
At dinner, Lara pulls out her computer to look at sites for the next day, and three children from the town gaze over her shoulder. She turns on photo booth, and lets them take pictures of themselves with silly faces.
On day two, we drive deeper into the jungle to Puerto Maldonado on the Madre de Dios River–one of the tributaries of the Amazon. The road here was supposed to be closed, but for a few soles, the policeman on duty lets us through. Even though it’s under construction, the road is good, and Lara jokes that we’re lacking in adventure.
Though she initially wanted to put a station near Puerto Maldonado, she decides to go a little bit north of where we are in order to line up the station with others in the array. She explains that there are two ways to create data from imaging—either with a grid of sites which makes two dimensional images, or with a scatter plot which creates three dimensional ones with slightly less accuracy. Her arrays are a hybrid between the two, with some grid lines and some intermediate points.
The images themselves come from the seismic waves which move through the earth at different speeds and angles. From these differences in speed, Lara can figure out how thick the earth’s crust is and whether the parts of the mantle she’s looking at are hot and melted or cold and solid. The hardness of the rock is reflected in the speed of the waves, so this can also give her clues about the properties and types of rock within the mantle.
At the end of the day, we find a site at a farm, but it’s too late to start digging. We drive back to a town called Santa Rosa, passing what Lara calls a “boomtown.” The buildings are made from beams and tarps, and the town is populated by mostly men on motorbikes. Women advertise bike washing, food, and before the town is over, a tarpaulin strip club.
Santa Rosa itself has run dry, meaning that there is no running water anywhere in town. Most of the people seem to be out on the sidewalk, buying fried rings of dough and fresh fish from a traveling vendor with a speaker on the hood of his car. We continue to the next town, which has no power, and find ourselves a shower and some food.