Impact crater provides insights into Martian craters
doi:10.1038/nindia.2014.79 Published online 5 June 2014
Researchers have investigated the morphology and degradation of the Lonar Crater in India, which was formed by a meteor impact, to provide vital insights into the morphology and evolution of similar craters on Mars1.
Since scientists are yet to set foot on Mars, they probe Martian-like landforms and environments on Earth to understand the geological and weathering processes on Mars. In the distant past, Mars and Earth were both bombarded by interplanetary debris, such as asteroids, comets and meteors. These bombardments created bowl-shaped depressions or impact craters.
The researchers investigated the Lonar Crater, a 1.8-km-wide impact crater in India. They studied some of the drainage systems of the crater, which harbours a shallow lake. The researchers found that surface runoff boosts the lake’s water level during the monsoon season, whereas groundwater flowed into the lake during both the rainy and dry seasons.
The crater does not have a continual input of water due to surface flow from the surrounding plains. The inner rim walls of the crater are steep. The drainage inside the crater rim collects rainfall or spring water and transports water and eroded sediments down to the crater floor in the lake. The walls of the inner rim have gullies and mass-wasting features, such as debris flows.
Like gullies in other impact craters, those in Lonar Crater were formed by rain runoff, which enhances the downward movement of mass. The Lonar Crater and the hydrological processes of Lonar Lake could provide insights into the degradation of other impact craters on Earth and ancient Mars.
1. Komatsu, G. et al. Drainage systems of Lonar Crater, India: contributions to Lonar Lake hydrology and crater degradation. Planet. Space. Sci. 95, 45–55 (2014) doi: 10.1016/j.pss.2013.05.011