Search results
Results From The WOW.Com Content Network
A central-peak crater is the most basic form of complex crater. A central-peak crater can have a tightly spaced, ring-like arrangement of peaks, thus be a peak ring crater, though the peak is often single. [3] Central-peak craters can occur in impact craters via meteorites. An Earthly example is Mistastin crater, in Canada. [1]
As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that often is symmetrical; with slopes between 30 and 40°; and a nearly circular ground plan. [4] Most cinder cones have a bowl-shaped crater at the summit. [2]
Compared to the thousands of volcanic eruptions that occur over the course of a century, the formation of a caldera is a rare event, occurring only a few times within a given window of 100 years. [3] Only eight caldera-forming collapses are known to have occurred between 1911 and 2018, [3] with a caldera collapse at Kīlauea, Hawaii in 2018. [4]
The EID lists fewer than ten such craters, and the largest in the last 100,000 years (100 ka) is the 4.5 km (2.8 mi) Rio Cuarto crater in Argentina. [2] However, there is some uncertainty regarding its origins [3] and age, with some sources giving it as < 10 ka [2] [4] while the EID gives a broader < 100 ka. [3]
The name maar comes from a Moselle Franconian dialect word used for the circular lakes of the Daun area of Germany. The word evolved from its first use in German in the modern geological sense in 1819 and is now used in English and in the geological sciences as the term for the explosion crater, even if water from rainfall might always have drained from the crater after the formation event.
Surface map of oceanic crust showing the generation of younger (red) crust and eventual destruction of older (blue) crust. This demonstrates the crustal spatial evolution at the Earth's surface dictated by plate tectonics. Earth's crustal evolution involves the formation, destruction and renewal of the rocky outer shell at that planet's surface.
In planetary geology, a pedestal crater is a crater with its ejecta sitting above the surrounding terrain and thereby forming a raised platform (like a pedestal).They form when an impact crater ejects material which forms an erosion-resistant layer, thus causing the immediate area to erode more slowly than the rest of the region.
The maar crater has been used for agriculture. There are two types of vent landforms from the explosive interaction of magma and ground or surface water; tuff cones and tuff rings. [ 1 ] Both of the landforms are associated with monogenetic volcanoes and polygenetic volcanoes .