scholarly journals Late Pleistocene glaciation history of the southern Black Forest, Germany: 10 Be cosmic‐ray exposure dating and equilibrium line altitude reconstructions in Sankt Wilhelmer Tal

2022 ◽  
Author(s):  
Felix Martin Hofmann ◽  
Frank Preusser ◽  
Irene Schimmelpfennig ◽  
Laëtitia Léanni ◽  
Aster team (Georges Aumaître, Karim Keddadouche & Fawzi Zaid
Keyword(s):  
Late Pleistocene ◽  
Cosmic Ray ◽  
Equilibrium Line ◽  
Pleistocene Glaciation ◽  
Black Forest ◽  
Equilibrium Line Altitude ◽  
Exposure Dating ◽  
History Of

Late Pleistocene glaciers in Darhad Basin, northern Mongolia

2008 ◽  
Vol 69 (2) ◽  
pp. 169-187 ◽  
Author(s):  
Alan R. Gillespie ◽  
Raymond M. Burke ◽  
Goro Komatsu ◽  
Amgalan Bayasgalan
Keyword(s):  
Central Asia ◽  
Lake Sediments ◽  
Late Pleistocene ◽  
Cosmic Ray ◽  
Luminescence Dating ◽  
Equilibrium Line ◽  
Equilibrium Line Altitude ◽  
Exposure Dating ◽  
Northern Mongolia ◽  
Dammed Lake

Late Pleistocene glaciers around Darhad Basin advanced to near their maximum positions at least three times, twice during the Zyrianka glaciation (at ∼ 17–19 ka and ∼ 35–53 ka), and at least once earlier. The Zyrianka glaciers were smaller than their predecessors, but the equilibrium-line altitude (ELA) difference was < 75 m. End moraines of the Zyrianka glaciers were ∼ 1600 m asl; ELAs were 2100–2400 m asl.14C and luminescence dating of lake sediments confirm the existence of paleolake highstands in Darhad Basin before ∼ 35 ka. Geologic evidence and10Be cosmic-ray exposure dating of drift suggests that at ∼ 17–19 ka the basin was filled at least briefly by a glacier-dammed lake ∼ 140 m deep. However, lake sediments from that time have not yet been recognized in the region. A shallower paleolake briefly occupied the basin at ∼ 11 ka, but between ∼ 11 and 17 ka and after ∼ 10 ka the basin was probably largely dry. The timing of maximum glacier advances in Darhad appears to be approximately synchronous across northern Mongolia, but different from Siberia and western Central Asia, supporting the inference that paleoclimate in Central Asia differed among regions.

Late Pleistocene Glaciation of the Southwestern Ahklun Mountains, Alaska

2000 ◽  
Vol 53 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Jason P. Briner ◽  
Darrell S. Kaufman
Keyword(s):  
Late Pleistocene ◽  
Equilibrium Line ◽  
Equilibrium Line Altitude ◽  
Sea Ice Extent ◽  
Ice Volume ◽  
Ice Cap ◽  
Global Ice Volume ◽  
Alpine Glaciers ◽  
Isotopic Signal ◽  
The Bering Sea

AbstractGlacial deposits in the southwestern Ahklun Mountains, southwestern Alaska, record two major glacier advances during the late Pleistocene. The Arolik Lake and Klak Creek glaciations took place during the early and late Wisconsin, respectively. During the Arolik Lake glaciation, outlet glaciers emanated from an ice cap centered over the central portion of the Ahklun Mountains and expanded beyond the present coast. During the Klak Creek glaciation, ice-cap outlet glaciers terminated ∼60 km upvalley from Arolik Lake moraines. The area also supported numerous alpine glaciers that expanded from small massifs. During both episodes of glaciation, these alpine glaciers apparently reached their maximum positions sometime after the retreat of the ice-cap outlet glaciers. Equilibrium-line altitudes for reconstructed alpine glaciers of the Klak Creek glaciation average ∼390 ± 100 m elevation in the western Ahklun Mountains, which is at most 500 m, and possibly only 200 m, below the estimated modern equilibrium-line altitude. The maximum late Pleistocene advance in the southwestern Ahklun Mountains occurred during the early Wisconsin, similar to advances elsewhere in western Alaska, but in contrast to the isotopic signal in the deep-sea record of global ice volume. The restricted extent of Klak Creek glaciers might reflect the increased distance to the Bering Sea resulting from eustatic sea-level regression and decreased evaporation resulting from lower sea-surface temperatures and increased sea-ice extent.

scholarly journals Implications of till-provenance studies for glaciological reconstructions of the paleoglaciers of Wildhorse Canyon, Idaho, U.S.A.

1996 ◽  
Vol 22 ◽  
pp. 93-101 ◽  
Author(s):  
Keith A. Brugger
Keyword(s):  
Late Pleistocene ◽  
Equilibrium Line ◽  
Equilibrium Line Altitude ◽  
Flow Paths ◽  
Orographic Effects ◽  
Provenance Studies ◽  
Provenance Data ◽  
Mineral Assemblages

Detailed till-provenance studies of moraine complexes in the Wildhorse Canyon area, Idaho, U.S.A., allow inferences to be made regarding the flow paths and dynamics of Wildhorse and Fall Creek Glaciers, the two principal tributaries constituting a late-Pleistocene compound glacier. In particular, the distribution of statistically defined pebble and mineral assemblages within moraine complexes suggests that Wildhorse Glacier contributed a substantially greater volume of ice to the trunk glacier than did Fall Creek Glacier.An initial group of glaciological reconstructions yields estimates for the equilibrium-line altitude (ELA) of the compound glacier that are consistent with those independently arrived at using other methods of ELA determination. Ice-flux calculations imply, however, that for each reconstruction the relative contributions of ice from Wildhorse and Fall Creek Glaciers were about equal, which is inconsistent with the inferences drawn from the till-provenance data. An alternative reconstruction incorporated possible orographic effects on accumulation and ablation by using different ELAs for the two tributary glaciers. Calculations for this reconstruction suggest that the ice flux of Wildhorse Glacier was about twice that of Fall Creek Glacier. This reconstruction is more consistent with the till-provenance data, and furthermore suggests that such data might be invaluable in choosing between seemingly equally viable glaciological reconstructions of paleoglaciers.

Late Pleistocene ice field on Jakupica Mt. (North Macedonia): extent and timing glaciation

2021 ◽  
Author(s):  
Zsófia Ruszkiczay-Rüdiger ◽  
Zoltán Kern ◽  
Marjan Temovski ◽  
Balázs Madarász ◽  
Ivica Milevski ◽  
...  
Keyword(s):  
Late Pleistocene ◽  
Cosmic Ray ◽  
Balkan Peninsula ◽  
Large Scatter ◽  
Last Deglaciation ◽  
Equilibrium Line Altitude ◽  
Extended Phase ◽  
Glacial Landforms ◽  
Exposure Ages ◽  
Southern Carpathians

&lt;p&gt;Since the 19&lt;sup&gt;th&lt;/sup&gt; century, geomorphological studies in the currently mainly unglaciated central Balkan Peninsula described extended glacial landforms and repeated glaciations. With the growing number of numerical ages an ambiguous picture has formed concerning the timing of the most extended glaciation and also on the glacier response to the cooling phases (e.g. Younger Dryas) during the last deglaciation of these mountain ranges.&lt;/p&gt;&lt;p&gt;This study provides &lt;sup&gt;10&lt;/sup&gt;Be cosmic ray exposure ages of a succession of glacial landforms in the Jakupica Mt. (North Macedonia), aiming to improve the understanding of Late Pleistocene glacier development in the area [1].&lt;/p&gt;&lt;p&gt;In the Jakupica Mt. (~41.7&amp;#176; N, ~21.4 E; Solunska Glava, 2540 m asl) a large plateau glacier was reconstructed (max. area ~45 km&lt;sup&gt;2&lt;/sup&gt;, max thickness: ~300 m), where three main ice accumulation areas could be delineated [2]. The study area comprises six northeastward facing, formerly glaciated valleys. Two of these valleys emerge from the plateau, one stands separate, and the remaining three are topographically separated by a relatively flat NNW-SSE oriented ridge. During the most extensive glacial stages, these three valleys were fed by ice overflowing above this ridge from the plateau. The lowest mapped moraines are descending down to 1550-1700 m asl suggesting the former existence of glacier tongues of ~3 km length. The large plateau ice and the complicated system of confluences makes glacier reconstructions and equilibrium line altitude (ELA) calculations challenging. Thus, the ELAs were preliminary estimated based on the maximum elevation of the lowermost lateral moraines, leading to ELA values of 1800&amp;#177;50 m a.s.l. for the most extended phase.&lt;/p&gt;&lt;p&gt;The maximum ice extent outlined by the lowest mapped moraines descending down to 1550-1500 m asl. occurred around ~24-19 ka (n=5), in agreement with the timing of the Last Glacial Maximum. During the Lateglacial, the exposure ages are getting younger by the glacier recession up to the moraines at ~1820 m asl (~19-14 ka, n=15). However, the highest sampled landforms (~2200 m asl) provided ages with a large scatter between ~25 and ~5 ka (n=6). This large scatter and the observed bias towards old ages are most probably the result of inherited cosmogenic nuclide concentrations within the rock. Consequently, &lt;sup&gt;10&lt;/sup&gt;Be exposure ages alone are apparently not suitable to determine the age of final deglaciation of this mountain. Similar conditions have been observed in the Retezat Mts (Southern Carpathians, Romania) [3].&lt;/p&gt;&lt;p&gt;This research was supported by the NKFIH FK124807 and GINOP-2.3.2-15-2016-00009 projects and by the Radiate Transnational Access 19001688-ST.&lt;/p&gt;&lt;p&gt;[1] Ruszkiczay-R&amp;#252;diger et al., 2020. Last deglaciation in the central Balkan Peninsula: Geochronological evidence from Jablanica Mt. (North Macedonia). Geomorphology 351: 106985&lt;/p&gt;&lt;p&gt;[2] Temovski et al., 2019. Glacial geomorphology of the northeastern part of the Jakupica Mountain, Macedonia, Central Balkan Peninsula. GRA 21, EGU2019-7822&lt;/p&gt;&lt;p&gt;[3] Ruszkiczay-R&amp;#252;diger et al., 2018. Glacier reconstruction, deglaciation chronology and paleo-environment reconstruction, Retezat Mountains, Southern Carpathians, Romania. Geologica Balcanica; Abstracts of the XXI. CBGA Congress, Salzburg, 10-13 September; p. 240-241.&lt;/p&gt;

Late Pleistocene glacial history of Jameson Land, central East Greenland, derived from cosmogenic10Be and26Al exposure dating

Boreas ◽  
2009 ◽  
Vol 38 (2) ◽  
pp. 244-260 ◽  
Author(s):  
LENA HÅKANSSON ◽  
HELENA ALEXANDERSON ◽  
CHRISTIAN HJORT ◽  
PER MÖLLER ◽  
JASON P. BRINER ◽  
...  
Keyword(s):  
Late Pleistocene ◽  
Glacial History ◽  
East Greenland ◽  
Exposure Dating ◽  
History Of

scholarly journals Implications of till-provenance studies for glaciological reconstructions of the paleoglaciers of Wildhorse Canyon, Idaho, U.S.A.

1996 ◽  
Vol 22 ◽  
pp. 93-101 ◽  
Author(s):  
Keith A. Brugger
Keyword(s):  
Late Pleistocene ◽  
Equilibrium Line ◽  
Equilibrium Line Altitude ◽  
Flow Paths ◽  
Orographic Effects ◽  
Provenance Studies ◽  
Provenance Data ◽  
Mineral Assemblages

Detailed till-provenance studies of moraine complexes in the Wildhorse Canyon area, Idaho, U.S.A., allow inferences to be made regarding the flow paths and dynamics of Wildhorse and Fall Creek Glaciers, the two principal tributaries constituting a late-Pleistocene compound glacier. In particular, the distribution of statistically defined pebble and mineral assemblages within moraine complexes suggests that Wildhorse Glacier contributed a substantially greater volume of ice to the trunk glacier than did Fall Creek Glacier.An initial group of glaciological reconstructions yields estimates for the equilibrium-line altitude (ELA) of the compound glacier that are consistent with those independently arrived at using other methods of ELA determination. Ice-flux calculations imply, however, that for each reconstruction the relative contributions of ice from Wildhorse and Fall Creek Glaciers were about equal, which is inconsistent with the inferences drawn from the till-provenance data. An alternative reconstruction incorporated possible orographic effects on accumulation and ablation by using different ELAs for the two tributary glaciers. Calculations for this reconstruction suggest that the ice flux of Wildhorse Glacier was about twice that of Fall Creek Glacier. This reconstruction is more consistent with the till-provenance data, and furthermore suggests that such data might be invaluable in choosing between seemingly equally viable glaciological reconstructions of paleoglaciers.

First cosmic ray exposure dating (in situ produced10Be) of the late pleistocene and holocene glaciation in the Nanhutashan Mountains (Taiwan)

Terra Nova ◽  
2007 ◽  
Vol 19 (5) ◽  
pp. 331-336 ◽  
Author(s):  
J. Carcaillet ◽  
L. L. Siame ◽  
H.-T. Chu ◽  
D. L. Bourlès ◽  
W.-C. Lu ◽  
...  
Keyword(s):  
Late Pleistocene ◽  
Cosmic Ray ◽  
Exposure Dating
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