Chronology of deglaciation based on 10 Be dates of glacial erosional features in the Grimsel Pass region, central Swiss Alps

• Published in: Boreas
• Main Authors: KELLY, MEREDITH A., IVY‐OCHS, SUSAN, KUBIK, PETER W., BLANCKENBURG, FRIEDHELM VON, SCHLÜCHTER, CHRISTIAN
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2006
• Subjects: Ice cap
• Online Access: http://dx.doi.org/10.1111/j.1502-3885.2006.tb01169.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1502-3885.2006.tb01169.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1502-3885.2006.tb01169.x

Surface exposure dating, using in situ produced cosmogenic 10 Be, is applied to determine the time since deglaciation of bedrock surfaces in the Grimsel Pass region. Nine 10 Be dates from bedrock surfaces corrected for cover by snow are minimum ages for deglaciation of the pass. Four 10 Be dates from surfaces below 2500 meters above sea level (m a.s.l.) on Nägelisgrätli, east of Grimsel Pass, yield ages that range from about 14 000 to 11 300 years. Three 10 Be dates from locations above 2600 m a.s.l. on Nägelisgrätli are between about 11 700 and 10 400 years. Two 10 Be dates from locations at 2560 m a.s.l. below Juchlistock are about 12 100 and 11 000 years. The geographical distribution of 10 Be dates on Nägelisgrätli either may show the timing of progressive deglaciation of Grimsel Pass or may reflect differences in subglacial erosion of bedrock in the pass region. All dates are discussed in the context of deglaciation of the late Würmian Alpine ice cap and deglaciation from Last Glacial Maximum (LGM) ice extents in other regions.