Valles Marineris

Croydon Caving Club Proposed Expedition To 'Valles Marineris'

Satellite photos and other remote sensing information have indicated the possibility of cave systems in this exotic location and following previous successful expeditions it is intended to tackle something a little further afield. Club members interested in what would be a world first should contact the expedition secretary. Below is a summary of the evidence for karst on Mars and an outline of the expedition programme. It should however be noted that the commencement date of the expedition is uncertain as certain technological elements are still under development.

Description of Expedition Area

The Valles Marineris is a global scale feature that is similar to the African Rift System. It is however 4 times deeper, 6 times wider and 10 times longer than the Grand Canyon. At the west end of the canyon in the Noctis Labyrinthus and from Tithonium Chasm to Western Coprates Chasma there are indications of collapse depressions indicating underground solution. Indeed it is thought possible that the whole of this enormous valley could be a limestone solutional feature a bit like Cheddar Gorge. It may seem incredible that there could be carbonates on Mars; there is however irrefutable evidence from trace element isotope data that at least 10 bar (1 bar = 1 atmosphere on earth) of CO2 has been outgassed from volcanoes which would have reacted with rocks (i.e. weathering) to form carbonate minerals which would then have been leached out by the early wet climate to form deposits and lakes. Indeed the plateau which the Valles truncates shows a layered lithology and in some areas lighter bands visible in Viking photographs could be limestone. The depth potential is at least 7km. There may also be extensive lava tubes.

Expedition Outline

Duration:- At least 3 years (travel 1 year each way)

Accommodation:- Accommodation during travel will be provided. Local travel and accommodation has yet to be devised.

Equipment:- Definitely nothing heavy although once there, weight is not a problem. Warm underwear and crampons as ice is expected. SRT gear needed for the 'sinks' although due to the low gravity only 4mm ropes needed.

Wetsuit:- Don't bother. Free water hasn't been seen for the last 2.5 billion years.

Spacesuit:- Required, as air pressure is only 1/100th. of ours. Good elbow and knee pads required as a rip would be fatal.

Cost:- Potentially the most expensive expedition ever planned. We intend however to apply to The Sports Council for a grant.

References:- Spencer et al. (1989) Karst on Mars? Origin of Closed Depressions on Mars by Solution of Carbonate 4th. International Conference on Mars, University of Tucson, Arizona. Catermole - Mars, The Story of The Red Planet.