Read the Beforeitsnews.com story here. Advertise at Before It's News here.
Profile image
By Alton Parrish (Reporter)
Contributor profile | More stories
Story Views
Now:
Last hour:
Last 24 hours:
Total:

Study Suggests Debris Flows On Arctic Sand Dunes Are Similar To Dark Dune Spot-Seepage Flows On Mars

% of readers think this story is Fact. Add your two cents.



 

A team of scientists from Southwest Research Institute (SwRI) has 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 that cascade down steep slopes.

 
Mars dunes
Credit: NASA

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.

 
 Great Kobuk Sand Dunes

Credit: Wikipedia

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. Such features were described in detail by a number of other researchers, and in particular by a team from Collegium Budapest, Institute for Advanced Study in Hungary.

Dark dune spot seepage flow features gave rise to the popularly known “trees on Mars” optical illusion that was associated with Mars Reconnaissance Orbiter HiRISE images of the flows. Such imagery was published “upside-down” online in an inverted orientation relative to the downward direction of gravity flows on dune slip faces, thus creating the tree-like dendritic pattern.

Dark dune spots are non-uniformly distributed on all frost-covered dune surfaces on Mars, but only those occurring near dune crests or on steep slip faces result in downslope flows. A thin brine layer may form and flow downslope on Martian sand dunes after the seasonally deposited carbon dioxide frost layer has begun to locally sublimate. Because of preferential energy adsorption by these dark, ice-free surfaces, localized heating and thawing at scales too small for orbital sensors to identify may yield briny Martian debris flows under current climate conditions.

The SwRI- and NASA-funded study was published today online under the title, “Debris Flows on the Great Kobuk Sand Dunes, Alaska: Implications for Analogous Processes on Mars,” by Drs. Don Hooper and Cynthia Dinwiddie in the journal Icarus.

Contacts and sources:
Joe Fohn
Southwest Research Institute



Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world. Anyone can join. Anyone can contribute. Anyone can become informed about their world. "United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.


LION'S MANE PRODUCT


Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules


Mushrooms are having a moment. One fabulous fungus in particular, lion’s mane, may help improve memory, depression and anxiety symptoms. They are also an excellent source of nutrients that show promise as a therapy for dementia, and other neurodegenerative diseases. If you’re living with anxiety or depression, you may be curious about all the therapy options out there — including the natural ones.Our Lion’s Mane WHOLE MIND Nootropic Blend has been formulated to utilize the potency of Lion’s mane but also include the benefits of four other Highly Beneficial Mushrooms. Synergistically, they work together to Build your health through improving cognitive function and immunity regardless of your age. Our Nootropic not only improves your Cognitive Function and Activates your Immune System, but it benefits growth of Essential Gut Flora, further enhancing your Vitality.



Our Formula includes: Lion’s Mane Mushrooms which Increase Brain Power through nerve growth, lessen anxiety, reduce depression, and improve concentration. Its an excellent adaptogen, promotes sleep and improves immunity. Shiitake Mushrooms which Fight cancer cells and infectious disease, boost the immune system, promotes brain function, and serves as a source of B vitamins. Maitake Mushrooms which regulate blood sugar levels of diabetics, reduce hypertension and boosts the immune system. Reishi Mushrooms which Fight inflammation, liver disease, fatigue, tumor growth and cancer. They Improve skin disorders and soothes digestive problems, stomach ulcers and leaky gut syndrome. Chaga Mushrooms which have anti-aging effects, boost immune function, improve stamina and athletic performance, even act as a natural aphrodisiac, fighting diabetes and improving liver function. Try Our Lion’s Mane WHOLE MIND Nootropic Blend 60 Capsules Today. Be 100% Satisfied or Receive a Full Money Back Guarantee. Order Yours Today by Following This Link.


Report abuse

    Comments

    Your Comments
    Question   Razz  Sad   Evil  Exclaim  Smile  Redface  Biggrin  Surprised  Eek   Confused   Cool  LOL   Mad   Twisted  Rolleyes   Wink  Idea  Arrow  Neutral  Cry   Mr. Green

    MOST RECENT
    Load more ...

    SignUp

    Login

    Newsletter

    Email this story
    Email this story

    If you really want to ban this commenter, please write down the reason:

    If you really want to disable all recommended stories, click on OK button. After that, you will be redirect to your options page.