Basalt floods on Mars and Iceland
Basalt floods on Mars and Iceland
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One of the defining characteristics of the surface of Mars is the rigid gap between Heavily craterized highlands in the two thirds of the south of the planet and the plains lower plains, younger That make up the northern third. Just north of the division is the Central Elysium Planitia- One of the two great volcanic regions on Mars and the location of the youngest volcanic rocks (approximately two million years) on the planet.
The region has dozens of gentle increase. shield volcanoes, some of which have torn long, narrow fissure vents on the surface Geologists believe that at some time between 500 and 2 million years ago, huge amounts of lava, and sometimes water, poured from these fissures, spilling over the surface and smoothing many craters. These lava buds are called "Flood basalts" or "traps"; On Earth, you can find famous examples in the state of Washington, India and Iceland.
However, Central Elysium Planitia has more impact craters than Earth, where they tend to erode quickly due to all the liquid water and the surface recycling that comes with active plate tectonics. According to an analysis, Central Elysium Planitia has approximately 15,000 impact craters despite its young age.
The image above, captured in 2012 by the Context camera about him Mars Reconnaissance Orbiter, shows a crater of this type with a distinctive hole of fissure and lava flow. The exact volume or age of the eruption that caused the lava flow in this Elysium Planitia crater is unclear. However, this seems to be a relatively young and small flow for this part of Mars.
The location of the ventilation inside the crater is probably a coincidence, although the force of the collision may have weakened the rock below the impact site in a way that made the magma more likely to arise. The crater is centered at 1 ° S, 160 ° W, which places it near the Martian equator. It is about 600 kilometers (400 miles) south of a much larger network of large fractures on the Martian surface known as Cerebus Fossae, the probable source of most of the lava that flooded Central Elysium Planitia in the last 200 million years.
Planetary geologists observe certain volcanoes on Earth to understand how volcanic processes develop on Mars. While there are some key differences, the basaltic lava flows on both planets have similarities. For example, there are parallels in the way that the flood basalt has poured from a vent in the Holuhraun lava field in Iceland in recent years and the way in which the flood basalt spread in the Elysium Planitia crater.
For this reason, a group of planetary scientists from NASA's Goddard Space Flight Center and researchers from the University of Arizona, the NASA Johnson Space Center and the University of St. Andrews traveled to Holuhraun in the summer of 2018 to study the young lava flow. . They there tested several sensors that could eventually be used in future satellite missions or by astronauts exploring Mars.
the Operational Earth Imager (OLI) in Landsat 8 captured an image of lava that flows from Holuhraun on January 2, 2015. false color image combines infrared short wave, near infrared and red light (Bands OLI 6-5-4). The vapor plume and sulfur dioxide appear white. The newly formed basaltic rock is black. The fresh lava is bright orange. The photographs on this page show members of the research team exploring the young basalt rock found at the Holuhraun vent in August 2018. The eruption in Holuhraun began in August 2015 and continued until February 2016, becoming the largest eruption of Iceland since 1783.
"In both cases, the fissures formed when the levees filled with basalt reached the surface and exploded," he explained. Patrick Whelley, a planetary scientist and part of the Goddard instrument field equipment. "Basalt does what basalt does"On both planets, although on Mars, the same lava pack tends to flow about six times farther than on Earth due to differences in surface pressure, temperature and gravity.
The conditions that affect the two lava flows are also quite different. With so much liquid water in Iceland, the flow of Holuhruan will erode rather quickly. In contrast, the Elysium Planitia Plant is so dry and cold that lava flows can remain virtually unchanged for long periods.
That does not mean that this part of the Central Elyesium Planitia has always been or always is dry. The surface of the plain contains evidence that huge episodic floods of water I've poured from those vents sometimes. The water flows were probably caused by the heat of the volcanic eruptions that melt the underground ice. Water may even have eroded the gap in the southeastern part of the crater rim before the lava spilled through it during a subsequent eruption, as observed Jacob richardson, a NASA planetary geologist and member of the GIFT team.
"Understanding where the lava is in the Elysium region built the landscape and where the water eroded and eroded is one of our main goals," Richardson said. "In many areas, like this one, it was probably a combination of both fluids."
You can learn more about the GIFT team by following your blog or looking #NASAFieldWork Y #NASAFireAndIce On twitter.
Images from the NASA Earth Observatory by Jesse Allen and Lauren Dauphin, using Landsat data from the United States Geological Survey and data from Context camera about him Mars Reconnaissance Orbiter. Photographs by Jacob Richardson for NASA. History of Adam Voiland, with information and verification of facts by Jacob Bleacher, Patrick Whelley, Jacob Richardson, Dan Berman and Gareth Morgan.
SOURCE LINK ERESVIRAL.COM https://www.beviral.online
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