Four Craters Lava Field facts for kids
Quick facts for kids Four Craters Lava Field |
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Craters of the aptly named Four Craters Lava Field are seen here from the NW on Green Mountain.
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| Highest point | |
| Elevation | 4,924 ft (1,501 m) |
| Geography | |
| Location | Lake County, Oregon, U.S. |
| Geology | |
| Age of rock | Pleistocene |
| Mountain type | volcanic field |
| Last eruption | < 50,000 years ago |
The Four Craters Lava Field is a special area in Oregon, USA. It is filled with cooled lava from old volcanoes. This field is found southeast of the Newberry Caldera. It covers a large area, about 30 square kilometers (that's like 30 squares, each 1 kilometer by 1 kilometer!).
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What is the Four Craters Lava Field?
This lava field gets its name from four main cinder cones. Cinder cones are small, cone-shaped volcanoes. They are made of volcanic ash and rock pieces. These four cones are the source of all the lava that flowed here. They are lined up in a row, pointing slightly northwest.
How Big Are the Cinder Cones?
The cones stand tall, rising between 75 and 120 meters above the lava flows. Imagine a 25-story building; that's how high some of them are! The distance from the northernmost cone to the southernmost one is about 3.5 kilometers. That's like walking for half an hour!
When Did the Volcanoes Erupt?
The volcanoes in this field erupted a very long time ago, during a period called the Pleistocene epoch. This was a time when giant ice sheets covered much of the Earth. The last eruption here happened less than 50,000 years ago. That might sound recent, but it was still a very long time before humans built cities!
Discovering Crack-in-the-Ground
Close to the Four Craters Lava Field, you can find a unique natural feature called Crack-in-the-Ground. It's located at the southwest edge of the lava field.
How Did the Crack Form?
When the volcanoes erupted, the ground underneath the older rocks slowly sank a little. This created a shallow, sunken area. This sunken area is about 3 kilometers wide. It stretches south into an old lake bed. Crack-in-the-Ground marks the western edge of this sunken area.
The crack itself is quite impressive. It is almost 9 meters deep and more than a meter wide in some places. It formed because the ground was pulled apart. This happened as lava flows from nearby Green Mountain draped over the edge of a hidden fault line. A fault line is a crack in the Earth's crust where rocks have moved.
