At lower temperatures, where atoms vibrate more slowly, the heavy isotope 13 C- 18 O bonds would be more difficult to break, resulting in a higher concentration of 13 C- 18 O bonds in calcite, compared to what is found at warmer temperatures.
By measuring the abundance of heavy isotope bonds in both low elevation warm sites and high elevation cooler sites over time, Garzione used the temperature difference between the sites to estimate the elevation of various layers of ancient soils at specific points in time. She found that the southern Altiplano region rose by about 2. Garzione speculates that the pulsing action relates to a dense root that grows at the boundary of the lower crust and upper mantle.
As the oceanic plate slips under the continental plate, the continental plate shortens and thickens, increasing the pressure on the lower crust. The basaltic composition of the lower crust converts to a very high-density rock called eclogite , which serves as an anchor to the low-density upper crust.
As this root is forced deeper into the hotter part of the mantle, it heats to a temperature where it can be rapidly removed over several million years , resulting in the rapid rise of the mountain range. The nearby town of Cajamarca has grown from 30, when the mine started to , people in The deep valley and rivers of the Andes give it huge potential as a region to produce hydroelectric power. The narrow valleys are ideal to dam as it cuts costs, and the steep relief increases water velocities allowing electricity generation.
Snow melt fuels most of the water provision, but this means that HEP production can be reduced to small amounts in winter. The Yuncan dam project dams the Puacartambo and Huachon rivers in northeast Peru, while the el Platinal project will begin construction in Tourism is a massive industry for Peru and the country has a lot to offer.
Peru has some fantastic coastline as well, but the highlight of Peru is undoubtedly the Inca Trail. You can take a virtual field trip of the Inca Trail here. The trail basically covers 43km of old pathways linking together old Inca settlements in the inhospitable mountains of the Andes. The trail is covered in 4 days and covers around 43km, and finishes with sunrise at the "Lost City of the Incas" at Machu Picchu. The trail is strictly controlled, and only trekkers are allowed to start out on the trail every day.
How the Andes Mountains are used. Farming The mountain slopes of the Andes are used for a variety of farming practises. Mining The Andes mountains contains a rich mix of minable materials that are both very valuable and very useful to man.
Hydroelectric power The deep valley and rivers of the Andes give it huge potential as a region to produce hydroelectric power. Tourism Tourism is a massive industry for Peru and the country has a lot to offer. Some images of the Andes mountains. A short video inside the Yanacocha gold mine. In the Altiplano, researchers expected to see cold rocks near the bottom of the lithosphere, at about 45 to 70 kilometers beneath the Andes. But the seismic waves showed that there were hot rocks there.
Garzione thinks that relatively cold, high-density rocks called eclogite detached as a blob and sank into the Earth. Once that eclogite blob dropped off, the overlying lithosphere bobbed higher, raising the plateau. They cross-check this story through geology. As sediment washed off the high Andes into the Altiplano, it built up into rock layers, producing an unprecedented environmental archive of the past.
The Altiplano rocks contain clues to the heights of different parts of the plateau at various points in its past. Some of the clues rely on the fact that temperatures generally get cooler the higher you go — think of driving up a mountain to escape the summer heat.
Those temperature differences are reflected in the differing amounts of heavy and light forms of elements such as oxygen and carbon in the Altiplano rocks. By measuring the chemical ratios in rocks of a certain age, scientists can figure out how high the Altiplano was at that time. In some places they found it was moving upward in bursts as rapid as half a kilometer or more every million years.
The Altiplano could have rocketed up so quickly only if something heavy, like an eclogite anchor, dropped off its bottom, she says. The process might even happen in cycles; after a cold blob drops off, another forms in its place and eventually detaches as well.
In at least one place beneath the eastern Andes, a combination of evidence suggests, one blob probably detached between 22 million and 17 million years ago, and a second one between 10 million and 5 million years ago. Still, there could be a second mechanism at work. Beneath the mountain ranges that border the Altiplano, to the west and the east of the plateau, the lithosphere is relatively thick. Heat rising from the asthenosphere can warm the lithosphere above, heating rocks so they flow like molasses from beneath the neighboring mountain ranges to beneath the Altiplano.
This process, known as crustal flow, could have helped the Altiplano thrust so rapidly upward during some periods. Some combination of the two may have ultimately pushed the Altiplano skyward, Garzione says.
When the eclogite anchor drops off, that detachment may cause hot rocks from the asthenosphere to well upward in the region, allowing the crustal flow to get going and the molasses to begin flowing. What scientists learn in the Andes can illuminate other parts of the world as well.
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