December 5, 2012
Ancient Mars Caverns May Have Captured Flood Water
Lee Rannals for redOrbit.com — Your Universe Online
Researchers have found evidence that ancient caverns on Mars may have captured enormous flood waters some 2 billion years ago.Planetary Science Institute researchers studied the terminal regions of the Hebrus Valles, which is an outflow channel that extends about 155 miles downstream from two zones of surface collapse.
The Martian outflow channels are made up of some of the largest known channels in the solar system. Although scientists have theorized that their discharge history may have once led to the formation of oceans, the ultimate fate and nature of the fluid discharges has remained a mystery for more than 40 years.
The scientists of the new research document the geomorphology of Hebrus Valles, which is a Martian terrain unique in that it preserves pristine landforms located at the terminal reaches of a Martian outflow channel.
The team proposed in an article published in Geophysical Research Letters that large volumes of catastrophic flood waters may have encountered their ultimate fate in vast cavernous systems.
PSI scientists believe that evacuated subsurface space during mud volcanism was an important process in cavern development. Mud volcanism can expel vast volumes of subsurface volatiles and sediments to the surface.
Because evacuation of subsurface materials generally occur within unconsolidated sediments resulting caverns are transient and mechanically highly unstable.
The Martian caverns appear to have developed within permafrost, which at negative 85 degrees Fahrenheit has a mechanical strength similar to that of limestone.
PSI research scientist J. Alexis Palmero Rodriguez said in a statement that the discovery of vast caverns that existed in ancient periods on Mars shows that these habitats may have existed during billions of years of the planet's history.