Remnants of lithalsas on the Hautes Fagnes plateau (Belgium) are on weathered quartzitic rocks

• Published in: Zeitschrift für Geomorphologie
• Main Author: Pissart, Albert
• Format: Article in Journal/Newspaper
• Language: English
• Published: Gebruder Borntraeger Verlagsbuchhandlung 2010
• Subjects: permafrost; Younger Dryas age; Hautes Fagnes Plateau; Physical; chemical; mathematical & earth Sciences; Earth sciences & physical geography; Physique; chimie; mathématiques & sciences de la terre; Sciences de la terre & géographie physique; Ice; palsas
• Online Access: https://orbi.uliege.be/handle/2268/250825; https://orbi.uliege.be/bitstream/2268/250825/1/Remnants_lithalsas_Hautes_Fagnes_Plateau.pdf; https://doi.org/10.1127/0372-8854/2010/0054-0001

peer reviewed The ramparted depressions that exist on the Hautes Fagnes Plateau in Belgium, first interpreted in 1956 as the remnants of pingos are best explained as remnants of lithalsas (i.e., mineral palsas), formed from ice segregation within frozen ground (permafrost) of Younger Dryas age. These features have only been described previously from Belgium, Wales and Ireland. Their location, above 500 m a.s.l. in Belgium, reflects the cold Younger-Dryas climate that have existed at that altitude but it was unclear why similar features did not form on the adjacent Eifel Plateau at the same altitude. We demonstrate here that lithalsas were formed only on weathered quartzitic rocks of the Cambro-Ordovician massif of Stavelot, and probably are associated with local hydrological conditions.