After a day of scampering up and down 40 degree hill slopes, knocking chunks of rock off outcrop into baggies our reward was a drive downhill. Silvia, our host and geologist/mining engineer from PUCP, Lima once took a colleague on this drive and he asked her "are you taking me to the center of the earth?". From Eastern Cordilleran mountains, down a two lane road with switch-backs innumerable, cutting our way down a gorge towards the Amazon jungle.
Roadside adobe/brick homes double as shops for fruits and snacks, children chasing dogs chasing dogs, water falls thin and pencil-straight, a major river channel filled with rounded boulders car-sized, and every free wall painted with political advertising. The mountain vegetation gave way to sub tropical growth with every imaginable shade of green in an unimaginable density, covering steep mountain slopes. We get to the turn-off for the Mine, down a dirt road, now darkness masks the lush surroundings and all the headlights see are the streams we ford as we bump along for 15 km, through a jungle town, then more dirt road to the entrance to the Mine site. A hot meal awaits us, served by mining staff in the mining food hall, we settle into guest housing and crash. Our morning meal of eggs on rice is followed by medical checkups, we all pass, and we suit up in mining gear, head to toe.
Entering a mix between a VW mini-bus and a jeep, we and 3 mining geologists/safety officers head into the 'hole'. It's a trick, we are into the earth, surrounded by rock, the claustrophobic gene gets activated, then we see light and we're out of the earth. A tunnel, perhaps to test how squeamish we'd be in the real hole. In we go, surrounded by rock, like a Disney ride, turning at the last second before smashing into rock wall, no light, but water is seen and heard. Driving through a maze for 15 minutes, headed 1000 m underground, it is beyond comprehension. No tunnel support, all rock around us. We are geologists, we now have our life in the hands of the rock we study. But such thoughts are quickly stifled, we leave the vehicle, stepping out into a large pool of water, ankle deep. the air is odd but not sour. Some have placed their respirators over their nose and mouth (like they teach you on airplanes), others taste the odd mine air directly. One tunnel entrance has been walled off by steel plating and we open a door in this plate to enter this passageway. A torrent of wind, near hurricane strength, blows into this new passageway as we walk, holding our hard-hats on, feeling the whipping wind and blowing water with every step. But 10 m into the passageway, the wind ceases, we're into the zone of rock of interest, black shale, and all eyes now scan the wall, ceiling, wall in this 6m x 6m tunnel. I love black shales, perhaps the oceanographer in me, Santa Monica Basin muds appear as rocks through this passageway. We struggle to tell where we are relative to where Kathleen sampled last year. Marking on the wet walls appear in our headlights (attached to our head), Josh coordinates sampling, Dave serves as a walking meter stick as we easily whack chunks of shale off the wall and into plastic bags. The rock is wet, the black comes off the rock leaving your hands black. Eight paces, another sample, eight paces another sample, headlights get taken off our helmets and into our hand to help us see up close, respirators come on and off as the air gets musty, cloudy, then clear. Communication with a respirator, possible but not easy, usually we remove the respirator to talk. The rocks are pretty stressed, but we are exhilarated, I mention to Josh that I'd like to overnight in the mine, some time later he said he would too. It's just that 'cool'. Bedding planes change, the shales are rocks that get stressed easily and these shales have been smushed, the ore deposits lie above and below, sometimes veins of mineralized fluid have shot through these mud rocks.
We finish our sampling, re-measure Dave the meter stick's pace, which is perfectly reproducible (!!) and we drive up and out of the wet dark hole. Into bright jungle light, we shed some gear but still in mining overalls, with shale dirt under fingernails, we enjoy lunch on a thatched-roof porch dining area overlooking immense greenery climbing up steep mountain slopes. Jungle birds speak to us, we listen to this amazing adventure from voices both within and out.
Very poetic! In my experience, black shale hands last for weeks, even with rigorous scrubbing!
ReplyDelete