technology-news

Debris flowing on frozen Arctic sand similar to dark dunes spot-seepage flows on Mars

Washington, Sept. 5 : A team of researchers have demonstrated that frozen water in the form of snow or frost can melt to form debris flows on sunward-facing slopes of sand dunes in the Alaskan arctic at air temperatures significantly below the melting point of water.


The debris flows consist of sand mixed with liquid water, which cascade down steep slopes.

Southwest Research Institute (SwRI) scientists made their observations at the Great Kobuk Sand Dunes, in Kobuk Valley National Park, Alaska.

This site serves as an Earth-based cold-climate "analog" to dunes on Mars. Debris flows formed on days when air temperatures measured continuously by the team remained below the melting point of water.

Very few minutes of above-freezing ground surface temperatures are needed to locally melt frozen water and mobilize sand down steep slopes.

The scientists hypothesize that fresh patches of wind-deposited dark sand on bright white snow caused local hot spots to form where solar radiation was absorbed by the sand and conducted into the underlying snow.

This enabled meltwater to briefly form and sand to be mobilized despite subfreezing local air temperatures. A similar mechanism may be responsible for triggering debris flows on frozen Martian sand dunes.

The Alaskan debris flows formed at ground temperatures that may correspond to those occurring locally and seasonally on the surface of Mars, said hydrogeologist Dr. Cynthia Dinwiddie, a principal engineer in SwRI's Geosciences and Engineering Division.

The Alaskan debris flows are morphologically similar to small, defrosting-related "dark dune spot" seepage flows that seasonally form in late winter on frost-covered Martian sand dunes.

--ANI (Posted on 07-09-2013)

technology-news headlines

New groundbreaking technique may help cure diseases by 'editing' DNA

Ancient Antarctica was as warm as today's California coast

Domesticated chili pepper originated in Central-east Mexico

Neanderthals carried more copies of potentially detrimental mutations

'Upside-down planet' reveals new method for studying binary star systems

Learn why homo sapiens survived when others could not

New material prevents plastic from ageing

Know if you are an app addict

Animals with bigger brain size more intelligent

Now, a detector to distinguish 'sour' oil from 'sweet'

UV lamp of the future is here

Shrimp-inspired material to make airplanes stronger

Quick Links: Goa | Munnar | Pondicherry | Free Yearly Horoscope '2014

Comments

Your e-mail:


Your Full Name:


Type verification image:
verification image, type it in the box

Message:

Back to Top