Erebus soul crystal1/27/2024 ![]() Volcanoes also provide a diary of earth’s past, offering many types of evidence about both the position of the continents and the time frames during which activity occurred. But they also result in destruction of existing areas, as red-hot lava and ash combine with the force of gravity to cover and disturb ecosystems. They deliver and distribute rock material from the earth’s mantle upward, creating new crust and developing new rocks and landforms on the continents. ![]() Volcanoes are both a productive and destructive force on earth. This evidence was fundamental to the acceptance of the theory of plate tectonics, which explains the changes in the position of ocean basins and continents driven by movements of the fluid materials in the earth’s interior. Those observations resulted in the graphic below that illustrates normal and reversed polarity in the rock layers. The most compelling evidence for the earth’s polar reversals was found in measurements of the magnetic field taken from ships traveling over the mid-ocean ridge system. As a result, the magnetic field of that day is recorded when the lava hardens. The minerals in the lava align themselves toward the earth’s magnetic field as the lava freezes. All magmas have enough iron-bearing minerals to detect the earth’s magnetic field. Lava is the perfect recorder of the earth’s magnetic field. Erebus enabled them to gather data from “recent” volcanic sites nearer to the South Pole. They were seeking evidence that the earth’s magnetic pole literally migrates from north to south when the reversals happen. They had also visited Costa Rica, where modern volcanoes erupt because of the subduction of an oceanic plate under continental crust. She and Hubert had been to Spitsbergen (Norway) and to the Azores and Canary Islands in previous years. The lava lake is red-hot molten rock, as can be seen in the close-up photo above and the NASA image below.Ĭathy, a geophysicist, was refining a model to explain how the earth’s magnetic field reverses from its “normal” position (today’s north and south) to the “reverse” (south becomes north). The volcano has been continuously active since 1972. Erebus has an outer crater about 650 meters (2,132 feet) wide that forms a distinct ring at approximately 3,200 meters of elevation, and an inner crater about 250 meters wide and 100 meters deep (820 by 328 feet) within which is an active lava lake. The volcano is a little over a million years old, but the upper portion is less than 100,000 years old. Erebus is a stratovolcano (made of many layers of igneous rock from eruptions) on top of a lower shield structure. Sidley, whose summit reaches 13,717 feet above sea level, is the only Antarctic volcano taller than Mt. Erebus is tall enough to be classified as an “ultra,” meaning that its summit reaches more than 10,000 feet above sea level. It is the highest point on Ross Island, home to both the U.S.-operated McMurdo Station and New Zealand’s main research station, Scott Base. Erebus is the largest active volcano and the second tallest volcano on Antarctica, with a summit elevation of 3,795 meters (12,451 feet). He named it and a nearby volcano after his two ships, Erebus and Terror. Erebus during an eruption on January 27, 1841. Sir James Clark Ross, a British naval officer and explorer, discovered Mt. Ross Island has three extinct volcanoes, and others are nearby on the mainland - in the Royal Society Range and the McMurdo Dry Valleys. It has sequential layers of rock on its flanks, but the area is also surrounded by many other lavas Hubert and Cathy could sample. Erebus is a fantastic lab for volcanologists. You cannot work when it’s really windy and cold. ![]() “The rim of the volcano can be really inhospitable. It’s the most important member of our party,” Hubert said. “We’ll have to see how the weather works with us. If it went well, they hoped to be finished in ten days…ten really good days. They planned to collect about 70 rock samples. They used this time to study photographs taken from a helicopter trip the day before to identify suitable sampling sites in the region. The day that I interviewed them, they had completed the necessary survival and skills training but were waiting for better weather to begin their research. In 2003, Hubert and his colleague, Cathy Constable, were at McMurdo Station for their first study of the volcanic history of Mt.
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