Mount Rittmann facts for kids
Quick facts for kids Mount Rittmann |
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|---|---|
 Location in Antarctica
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| Highest point | |
| Elevation | 2,600 m (8,500 ft) |
| Naming | |
| Etymology | Volcanologist Alfred Rittmann |
| Geography | |
| Parent range | Mountaineer Range |
| Geology | |
| Age of rock | Pliocene |
| Mountain type | Volcano |
| Volcanic belt | McMurdo Volcanic Group |
| Last eruption | >1254 CE |
Mount Rittmann is a cool volcano found in Antarctica. It was first seen by an Italian team in 1988–1989. The volcano is named after a famous scientist who studied volcanoes, Alfred Rittmann (1893–1980).
Mount Rittmann has a huge bowl-shaped area called a caldera. This caldera is about 2 kilometers (or 8 by 5 kilometers) wide. It peeks out from under the Aviator Glacier. This volcano was very active a long, long time ago, even having big explosive eruptions. One huge eruption happened in 1254 CE. It spread ash and tiny rock pieces all over Antarctica! Today, Mount Rittmann is considered a dormant volcano. This means it's sleeping but could wake up again.
What's really special about Mount Rittmann is that it has fumaroles. These are like natural steam vents. The heat from these vents keeps some parts of the caldera free of ice. Because of this warmth, tiny mosses and different kinds of microorganisms can actually grow there! Finding mosses on active volcanoes in Antarctica is super rare. It only happens at Mount Rittmann, Mount Melbourne, and Mount Erebus. Because of this unique life, people are working to make Mount Rittmann a protected area.
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Discovering Mount Rittmann
Mount Rittmann is located in Victoria Land, which is part of the Ross Sea area in Antarctica. It's about 100 kilometers from Terranova Bay. It's also about 150 kilometers from the Italian Mario Zucchelli Station.
As mentioned, an Italian expedition first found this volcano in 1988–1989. They decided to name it after the volcanologist Alfred Rittmann. This was a way to honor his important work in studying volcanoes.
What Mount Rittmann Looks Like
Mount Rittmann stands tall at about 2600 meters high. It's part of the Mountaineer Range. The large caldera (the big bowl-shaped crater) is mostly hidden under the Aviator Glacier. You can see its edges because a ring of volcanic hills and rocks sticks out from the flat, icy land around it.
Sometimes, the name Mount Rittmann refers to a specific warm, rocky peak on the caldera's edge. This peak is called a nunatak. The base of the volcano also shows through the Pilot Glacier. These rocky areas are some of the only parts of the volcano not covered by snow and ice. The rocks you can see are made of things like hyaloclastites, lava flows, and pillow lavas.
Warm Vents and Special Life
In 1990–1991, another Italian team found warm ground and fumaroles at the caldera. This means there's still molten magma deep inside the volcano, keeping it warm. The fumaroles are found on a sandy-gravelly slope. There's also another warm spot on the lower parts of the volcano.
The vents where the steam comes out are small, only a few centimeters wide. They are surrounded by white crusts. These crusts form from rocks changed by the hot water and steam. The gases coming out of the fumaroles are mostly carbon dioxide. You can't smell any sulfur there.
These fumaroles keep an area of the caldera, high up at 2250 meters, completely free of ice. Even though the average temperature at 2100 meters is around -20 degrees Celsius, the fumaroles heat the nearby rocks up to 60 degrees Celsius! The surface of the ground can get as warm as 43.4 degrees Celsius.
Small patches of moss grow in these warm, sandy areas. They grow in a round, rosette shape. The constant water supply from the steam, the warmth, and the shelter allow these plants to live. You can also find this kind of volcanic plant life at Mount Erebus and Mount Melbourne. Scientists think the mosses might have been carried there by the wind. The type of moss found, Pohlia nutans, grows all over the world. It's also found in other parts of Victoria Land. Genetic studies show that all the mosses at Mount Rittmann likely came from one single event.
Scientists have also studied the tiny living things, called microbes, that live near the fumaroles. They've found different kinds of bacteria, including cyanobacteria, and fungi like yeast. There are also mats of cyanobacteria, algae, and protozoa. Some special bacteria were even discovered here, like Anoxybacillus amylolyticus and Alicyclobacillus acidocaldarius subsp. rittmannii. Another bacterium, Bacillus fumarioli, was found at both Mount Rittmann and Mount Melbourne. Alicyclobacillus acidocaldarius subsp. rittmannii is even used in studies of special enzymes that work well in hot temperatures. Another heat-loving bacterium found here is Aneurinibacillus terranovensis.
Mount Rittmann is one of only four volcanoes in Antarctica known to have these special warm habitats. The others are Deception Island, Mount Erebus, and Mount Melbourne. Mount Rittmann is the least studied of these.
Organizations like Antarctica New Zealand are working to make Mount Rittmann an Antarctic Specially Protected Area (ASPA). This would help protect its unique environment. In 2014, Mount Rittmann was reportedly part of ASPA 175.
How Mount Rittmann Formed
Mount Rittmann is part of the McMurdo Volcanic Group. This is one of the biggest areas in the world with a certain type of volcanic rock. The volcanic activity here is linked to how the Ross Sea floor spread apart. Volcanoes in this region started forming millions of years ago and continued into recent times.
The rocks around the caldera rim are made of breccia. This rock contains pieces of young pumice and other rocks called xenoliths. The volcanic rocks here are a mix of different types, including basanitic, hawaiitic, mugearitic, phonolithic, and trachytic rocks. They often contain crystals of olivine and plagioclase. The xenoliths can be pieces of granite and other metamorphic rocks from deep underground. Near the fumaroles, the rocks have been changed by the hot water and steam.
Mount Rittmann's Eruption History
Mount Rittmann is an old volcano, dating back to the Pliocene period. It was active between 4 million and 70,000 years ago. Scientists have used special dating methods to find the ages of its rocks. For example, some rocks at the base are 3.97 million years old. Other lava flows are much younger, around 240,000, 170,000, and 70,000 years old.
The caldera itself seems to be younger than some of the older rocks. It might have formed from a very powerful eruption called a Plinian eruption. Scientists think that ash layers found in different parts of Antarctica might have come from Mount Rittmann. This includes ash found in ice cores and at places like Talos Dome. At least four big eruptions happened in the last 74,000 years. It's hard to know the full eruption history because not many of its rocks are exposed.
Around 11,000 years ago, Mount Rittmann had a huge explosive eruption. This eruption left behind a layer of ash called the "Aviator Tephra" in the Aviator Basin of the Ross Sea. Scientists believe this eruption started as a hydromagmatic event. This means water from ice mixed with the hot magma. Then, it turned into a powerful Plinian eruption that shot out small rocks called lapilli and volcanic ash. The volcano was probably covered in ice when this eruption began. The melting ice likely caused the explosive interaction with the magma. After the eruption, the caldera might have collapsed, and the volcano produced ignimbrites.
Scientists have also found evidence that Mount Rittmann erupted in 1254 CE. This eruption left a layer of ash, known as the Rittmann tephra or "1254 C.E. tephra," all across Antarctica. This ash has been found in ice cores in both East and West Antarctica. Its discovery at Edisto Inlet shows that it spread over a huge area, more than 950,000 square kilometers. This means it traveled over 2000 kilometers from the volcano! The eruption was very efficient at breaking up the magma into tiny pieces. It was likely one of the biggest eruptions in Antarctica in the last 10,000 years. Before its source was found, people thought it came from The Pleiades volcanoes.
It's possible that more eruptions have happened since 1254. Right now, the volcano is considered quiet. It's not actively monitored, but a station that detects ground movements was set up nearby. Satellites have also seen small warm spots. These might be signs of the fumaroles. If an eruption like the 1254 one happened again, it could create a long-lasting ash cloud. This ash could fall on nearby research stations. It could also cause problems for air traffic going to and from McMurdo Station.
