structural periglacial grounds; Chambeyron; field experience; High Mountains; sols structuraux périglaciaires; sol structural périglaciaire; expériences de terrain; Haute montagne
Abstract :
[en] ln the Chambeyron massif, between 2800 and 3000 m above sea level, reference marks have thrown light on geomorphological processes which operate in the formation and evolution of periglacial patterned ground.
I. Polygones of several decimeters diameter
The observed processes are:
1. The formation of a polygonal net of contraction cracks which persisted for years but opened and closed (fig.1et3);
2. the appearance on the surface of pebbles uplifted by frost (fig. 2);
3. the movement of the pebbles on the surface to the stony borders (fig.1, 2 et 3);
4. the presence of mass movement in the center of the polygones (fig. 4 et 5).
II. Polygones of almost a meter diameter
Painted stones buried in these polygones appeared rapidly on the surface.
Painted stones placed on the surface move quickly to the borders of small secundary polygones where some have moved clown to a depth of several centimeters in 5 years.
III. Stripes of several decimeters width
Painted stones buried in the fine bands appeared rapidly on the surface and then moved to the stony band. lt is not clear if the rate of movement downslope is greater in the stony bands
than in the fine bands.
IV. Stripes of almost one meter width .
Ten years obserbations of painted lines have shown that the fine bands move downslope more quickly than the stony bands (fig. 7). Vertical bands of coloured fine matérial showed that this movement was rapid only very close to the surface (fig. 8).
This website uses cookies to improve user experience. Read more
Save & Close
Accept all
Decline all
Show detailsHide details
Cookie declaration
About cookies
Strictly necessary
Performance
Strictly necessary cookies allow core website functionality such as user login and account management. The website cannot be used properly without strictly necessary cookies.
This cookie is used by Cookie-Script.com service to remember visitor cookie consent preferences. It is necessary for Cookie-Script.com cookie banner to work properly.
Performance cookies are used to see how visitors use the website, eg. analytics cookies. Those cookies cannot be used to directly identify a certain visitor.
Used to store the attribution information, the referrer initially used to visit the website
Cookies are small text files that are placed on your computer by websites that you visit. Websites use cookies to help users navigate efficiently and perform certain functions. Cookies that are required for the website to operate properly are allowed to be set without your permission. All other cookies need to be approved before they can be set in the browser.
You can change your consent to cookie usage at any time on our Privacy Policy page.