Mars Express Maps 1,300-km Shalbatana Vallis, Tracing 3.5-Billion-Year-Old Martian Floods
Updated
Updated · European Space Agency · May 13
Mars Express Maps 1,300-km Shalbatana Vallis, Tracing 3.5-Billion-Year-Old Martian Floods
4 articles · Updated · European Space Agency · May 13
ESA’s Mars Express released new views of Shalbatana Vallis, a 1,300-km channel near Mars’s equator whose main valley is about 10 km wide and 500 m deep.
The imagery and analysis indicate catastrophic groundwater floods carved the valley about 3.5 billion years ago, cutting through rock as water surged downhill from Xanthe Terra toward Chryse Planitia.
Blue-black deposits in the channel point to later wind-blown volcanic ash, while chaotic terrain nearby suggests melting subsurface ice collapsed the ground after the valley formed.
Smooth surrounding terrain, wrinkle ridges, mesas and impact craters show the area was later reshaped by lava, erosion and repeated impacts.
Chryse Planitia, where many major outflow channels end, is among Mars’s lowest regions and has long been cited as a possible site of an ancient ocean.
What geological evidence could still challenge the new theory of a vast Martian ocean?
As 'marsquakes' hint at active magma, could Mars’s giant volcanoes erupt again?
What signs of life will rovers now seek on Mars's newly discovered ancient ocean coastlines?
Mars Express Unveils a Dynamic Red Planet: Surface Changes, Volcanic Ash, and Water Ice Transform Exploration Plans
Overview
Recent observations from ESA's Mars Express mission are fundamentally reshaping our understanding of Mars. The data reveal that the Red Planet is far more dynamic than previously believed, challenging long-held assumptions about its geological activity. In particular, Utopia Planitia, once thought to have held a vast body of water, now contains substantial subsurface ice and shows many features of past water flow. Strikingly, a comparison of images from NASA's Viking mission in 1976 and Mars Express in 2024 reveals notable changes in the distribution of volcanic ash, highlighting that Mars's surface is actively changing and not as geologically inert as once assumed.