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Full-Text Articles in Geology
Cosmogenic 10be And 36cl Ages From Late Pleistocene Terminal Moraine Complexes In The Taylor River Drainage Basin, Central Colorado, U.S.A., Keith A. Brugger
Cosmogenic 10be And 36cl Ages From Late Pleistocene Terminal Moraine Complexes In The Taylor River Drainage Basin, Central Colorado, U.S.A., Keith A. Brugger
Geology Publications
Cosmogenic surface-exposure ages from boulders on a terminal moraine complex establish the timing of the local last glacial maximum (LGM) in the Taylor River drainage basin, central Colorado. Five zero-erosion 10Be ages have a mean of 19.5±1.8 ka while that for three 36Cl ages is 20.7±2.3 ka. Corrections for modest rates (∼1 mm ka−1) of boulder surface erosion result in individual and mean ages that are generally within 2% of their zero-erosion values. Both the means and the range in ages of individual boulders are consistent with those reported for late Pleistocene moraines elsewhere in the …
The Non-Synchronous Response To Rabots Glaciar And Storglaciaren, Northern Sweden, To Recent Climate Change: A Comparative Study, Keith A. Brugger
The Non-Synchronous Response To Rabots Glaciar And Storglaciaren, Northern Sweden, To Recent Climate Change: A Comparative Study, Keith A. Brugger
Geology Publications
Rabots Glaciar and Storglaciaren, two small valley glaciers in the Swedish Arctic, have not behaved synchronously in response to recent climate change. Both glaciers advanced late in the 19th century and then began to retreat in response to an approximately 1 degree C warming that occurred around 1910. By the mid-1980s the terminus and volume of Storglaciaren had essentially stabilized, so it may have completed its response to the earlier warming. In contrast, ongoing thinning and retreat of Rabots Glaciar are substantial and suggest its response time is considerably longer. A time-dependent numerical model was used to investigate each glacier’s …
Rock Glaciers In Central Colorado, U.S.A., As Indicators Of Holocene Climate Change, Kurt A. Refsnider, Keith A. Brugger
Rock Glaciers In Central Colorado, U.S.A., As Indicators Of Holocene Climate Change, Kurt A. Refsnider, Keith A. Brugger
Geology Publications
We measured thalli diameters of the lichen Rhizocarpon subgenus Rhizocarpon on 48 individual lobes of 18 rock glaciers and rock glacier complexes in the Elk Mountains and Sawatch Range of central Colorado. Cumulative probability distribution and K-means clustering analyses were used to separate lichen thalli measurements into statistically-distinct groups, each interpreted as representing a discrete episode of rock glacier activity driven by an interval of cooler climate. Lichen ages for these episodes were assigned using a growth curve developed for Rhizocarpon geographicum in the nearby Front Range. An early Neoglacial episode, ca. 3080 yr BP, is correlative to other glacial …