GSA home

Log In | GSA Community | GSA Store | Join GSA | Donate | Contact Us

GSA home

| GSA Community | GSA Store | Donate | Contact Us

About GSA

Connected Community

Divisions &
Associated Societies

Education & Outreach

GSA Foundation

Meetings

Membership

Newsroom

Public Policy

Publications

Resources & Jobs

Sections

Find Your Science at GSA
24 Feb. 2012
GSA Release No. 12-11
Contact:
Christa Stratton
Director - GSA Communications & Marketing
+1-303-357-1093
Zhou Figure 2
Artificially excavated cross sections showing internal structures of linear dunes (Fig. 2 of Zhou et al.). Click on picture for larger image.

Bookmark and Share

GSA BULLETIN: New Research Points to Erosional Origin of Linear Dunes


Boulder, CO, USA – 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 salt content 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 luminescence 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.”

Dr. Zhou would like to acknowledge Dr. Jani Radebaugh for her careful and constructive reviews of the study.

GSA BULLETIN articles published ahead of print can be accessed online at http://gsabulletin.gsapubs.org/content/early/recent. When articles are assigned to a print issue they will be removed from the pre-issue publication folder, but doi numbers will remain constant.

Abstracts for issues of GSA BULLETIN are available at http://gsabulletin.gsapubs.org/. Sign up for pre-issue publication e-alerts for at http://www.gsapubs.org/cgi/alerts for first access to new journal content as it is posted. Subscribe to RSS feeds at http://gsabulletin.gsapubs.org/rss/.

Representatives of the media may obtain complimentary articles by contacting Christa Stratton. Please discuss articles of interest with the authors before publishing stories on their work, and please make reference to GSA BULLETIN in your articles or blog posts. Contact Christa Stratton for additional information or assistance.

Non-media requests for articles may be directed to GSA Sales and Service, .

***************
Origin and lateral migration of linear dunes in the Qaidam Basin of NW China revealed by dune sediments, internal structures and optically stimulated luminescence ages, with implications for linear dunes on Titan
Jianxun Zhou et al., State Key Laboratory of Petroleum Resource & Prospecting, China University of Petroleum, Beijing 102249, China; doi: 10.1130/B30550.1.

###

The Geological Society of America, founded in 1888, is a scientific society with more than 25,000 members from academia, government, and industry in 103 countries. Through its meetings, publications, and programs, GSA enhances the professional growth of its members and promotes the geosciences in the service of humankind. Headquartered in Boulder, Colorado, GSA encourages cooperative research among earth, life, planetary, and social scientists, fosters public dialogue on geoscience issues, and supports all levels of earth science education.

www.geosociety.org