Did you think that the area occupied by Olympus Mons (300,000 square kilometres) was unimaginably big? Wait till you hear how much of Martian land the shield volcano Alba Mons covers. At least 5.7 million square kilometres! That’s more than half the size of Europe!
With respect to area, Alba Mons may be the largest volcano on Mars. But it stands only 6.8 kilometres tall; that is hardly one-third the height of Olympus Mons! You can guess looking at its dimensions that this volcano has a very gentle slope. With an average slope of just 0.5 degrees even at its steepest northern side, this “mountain” looks nothing like the ones we have here on the Earth!
In reality, until 2007 Alba Mons (Latin for “white mountain”) used to be called Alba Patera (Latin for “white saucer”) because of the white clouds found around the volcanic craters of the mountain. Today, Alba Patera refers only to the two calderas (hollowed out regions found on top of volcanoes after an eruption), the larger of which is more than 100 kilometres wide. They are relatively shallow though – only about one kilometre deep! Curved fault lines, called Tantalus Fossae and Alba Fossae, run on the eastern and western sides of the volcano. We can also find evidence of lava flows and surface water run-off around it.
Picture Credit : Google
