Washington, December 17 (ANI): In a new research, a tam of scientists has reported new evidence for multiple, water-related geologic processes on Mars, thus indicating that the Red Planet had a complex hydrological past.
Catherine Weitz, a senior scientist at the Tucson-based Planetary Science Institute, and her colleagues studied light-toned deposits (LTDs) within troughs of the Noctis Labyrinthus region in western Valles Marineris using data gathered by three Mars Reconnaissance Orbiter (MRO) instruments.
"We analyzed ten troughs containing well-exposed LTDs, and we found a lot of variability that we didn't expect to see," she said.
"We found that each of the troughs with LTDs has a unique mineralogy, and, therefore, the processes occurring in each trough were very localized," she added.
Weitz and her team identified various types of clays, hydrated silicas, and sulfates in these small basins, which are typically 30 to 100 kilometers across.
One LTD included dozens of beds of varying thickness, brightness, color and erosional structure, suggesting that significant amounts of water once existed there.
In addition, sulfates were mixed with clays within the deposits, indicating that ph levels may have fluctuated between acidic and alkaline conditions.
Another LTD is buried several meters beneath wind-deposited material and is only exposed in the trough's upper walls, indicating it is older than the trough.
In still another area, clays are buried beneath younger plains along the trough floor, while in the same trough, but a few kilometers away, there are exposures of hydrated silica and calcium sulfate.
The wide variability in deposits and mineralogy in these and the other basins suggests a complex hydrologic history, including multiple events in some troughs, according to Weitz.
"Clearly, these areas were affected by water," she said. "In some cases, there had to be multiple events. But we don't know how much water was involved or whether it was always a flowing liquid," she added.
"It might have been groundwater coming from Tharsis, the large volcanic complex to the west," she said.
According to Weitz, "There could have been active volcanism that produced water by melting snow, ice, or underground, hydrothermal processes. These little basins could then have filled or partially filled with some of that water."
"Another possibility is that material was already in several of the troughs, perhaps as volcanic ash or lava flows, and some kind of hydrothermal activity may have altered these pre-existing deposits," she said. (ANI)
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