New research points to erosional origin of linear dunes

Feb 24, 2012
Artificially excavated cross sections showing internal structures of linear dunes (Fig. 2 of Zhou et al.).

Linear dunes, widespread on Earth and Saturn's moon, Titan, are generally considered to have been formed by deposits of windblown sand. It has been speculated for some time that some linear dunes may have formed by "wind-rift" erosion, but this model has commonly been rejected due to lack of sufficient evidence. Now, new research supported by China's NSF and published this week in GSA BULLETIN indicates that erosional origin models should not be ruled out.

The linear dunes in China's Qaidam Basin have been proposed to have formed as self-extending lee dunes under a unidirectional wind regime owing to a high level of total silt, clay, and or cohesiveness of sediments, and they have undergone southward lateral migration at rates of up to 3 m/yr.

New GSA BULLETIN research examines the sediments, internal structures, and optically stimulated ages of the linear dunes in the central Qaidam Basin approximately 80 km north of the city Golmud. The study's findings suggest that the linear dunes are most likely of erosional origin similar to yardangs with orientations controlled by strikes of joints.

According to the study's lead author, Jianxun Zhou of the China University of Petroleum's State Key Laboratory of Petroleum Resource & Prospecting, "If the control of tectonic structures on the orientation of wind-eroded ridges is taken into account, morphodynamic interpretations for the wind-rift model may become much simpler. No one has considered the possibility of erosional origin for the linear dunes on Titan. Nearly all researchers consider the linear dunes on Titan to be of depositional origin, but their morphodynamic interpretations are complicated and their relationships to wind directions are in dispute. If an erosional origin is considered, the morphodynamic interpretations of the linear dunes on Titan can also be greatly simplified."

Explore further: Mysteries of space dust revealed

More information: Jianxun Zhou et al., State Key Laboratory of Petroleum Resource & Prospecting, China University of Petroleum, Beijing 102249, China; doi: 10.1130/B30550.1

Provided by Geological Society of America

3 /5 (1 vote)
add to favorites email to friend print save as pdf

Related Stories

Cassini Maps Global Pattern of Titan's Dunes

Feb 27, 2009

(PhysOrg.com) -- Titan's vast dune fields, which may act like weather vanes to determine general wind direction on Saturn's biggest moon, have been mapped by scientists who compiled four years of radar data ...

In deserts, which dunes are the most stable?

May 28, 2010

By modeling a desert where the wind blows in two directions, French researchers from CNRS and Universite Paris Dideror have succeeded in observing and highlighting, for the very first time, the formation process ...

Putting it all together on Titan

Aug 09, 2011

Three of Titan's major surface features -- dunes, craters and the enigmatic Xanadu -- appear in this radar image from NASA's Cassini spacecraft. The hazy, bright area at the left that extends to the lower ...

Cassini sees the two faces of Titan's Dunes

Jan 24, 2012

(PhysOrg.com) -- A new analysis of radar data from NASA's Cassini mission, in partnership with the European Space Agency and the Italian Space Agency, has revealed regional variations among sand dunes on Saturn's ...

Recommended for you

Mysteries of space dust revealed

17 hours ago

The first analysis of space dust collected by a special collector onboard NASA's Stardust mission and sent back to Earth for study in 2006 suggests the tiny specks open a door to studying the origins of the ...

A guide to the 2014 Neptune opposition season

22 hours ago

Never seen Neptune? Now is a good time to try, as the outermost ice giant world reaches opposition this weekend at 14:00 Universal Time (UT) or 10:00 AM EDT on Friday, August 29th. This means that the distant ...

Informing NASA's Asteroid Initiative: A citizen forum

Aug 28, 2014

In its history, the Earth has been repeatedly struck by asteroids, large chunks of rock from space that can cause considerable damage in a collision. Can we—or should we—try to protect Earth from potentially ...

Image: Rosetta's comet looms

Aug 28, 2014

Wow! Rosetta is getting ever-closer to its target comet by the day. This navigation camera shot from Aug. 23 shows that the spacecraft is so close to Comet 67P/Churyumov-Gerasimenko that it's difficult to ...

User comments : 0