Christian Schlüchter

Universität Bern | UniBe · Institute of Geological Sciences

Les variations des glaciers lors du Petit Âge Glaciaire (PAG) sont bien connues dans les Alpes, en partie grâce à un ensemble inégalé de sources historiques. Lorsque ces dernières sont absentes, la dendrochronologie peut être utilisée pour obtenir des informations chronologiques précises sur les maxima des glaciers. Pour ce faire, il faut cibler le...

Little Ice Age (LIA) glacier variations are well constrained in the Alps, partly thanks to an unparalleled body of historical sources. When absent, tree-ring dating can be used to obtain accurate chronological information on glacier maxima. To do so, it is necessary to focus on the trees that immediately bordered the former maximum extent reached b...

The importance of the stable isotopes in tree rings for the study of the climate variations caused by volcanic eruptions is still unclear. We studied δ18O, δD, δ13C stable isotopes of larch and cembran pine cellulose around four major eruptions with annual resolution, along with a superposed epoch analysis of 34 eruptions with 5-year resolution. In...

Barhal Valley belongs to the Çoruh Valley System in the Kaçkar Mountains of northeastern Anatolia. This 13 km long valley is located to the south of the main weather divide and to the east of Mt. Kaçkar, with the highest peak of the mountain range being 3932 m. Today, source of an average yearly precipitation of 2000 mm of moisture is the Black Sea...

Since the early twentieth century, a prominent end moraine at the village of Trins in the Gschnitz Valley in the Tyrolean Alps serves as type locality for an alpine-wide lateglacial phase of glacier advances. Dating of the moraine with the terrestrial cosmogenic radionuclide 10Be gives a stabilization age for the moraine in the range of 16.6 ± 1.4...

The term ‘Little Ice Age’ (LIA) is classically used to define a period of repeated and extensive glacier advances during the last millennium. In the meanwhile, this term is also used to address the period of relatively low temperatures between the Medieval Climate Anomaly (MCA), or Medieval Warm Period, and present-day warming. The end of the LIA i...

The Sun sporadically produces eruptive events leading to intense fluxes of solar energetic particles (SEPs) that dramatically disrupt the near-Earth radiation environment. Such events have been directly studied for the last decades but little is known about the occurrence and magnitude of rare, extreme SEP events. Presently, a few events that produ...

Mid-latitude mountain glaciers are sensitive to local summer temperature changes. Chronologies of past glacier fluctuations based on the investigation of glacial landforms therefore allow for a better understanding of natural climate variability at local scale, which is relevant for the assessment of the ongoing anthropogenic climate warming. In th...

Citation: Arosio, T.; Ziehmer-Wenz, M.M.; Nicolussi, K.; Schlüchter, C.; Leuenberger, M.C. Investigating Masking Effects of Age Trends on the Correlations among Tree Ring Proxies. Forests 2021, 12, 1523. https:// Abstract: Age-related trends are present in tree-ring widths (TRW), but their presence in tree rings isotope is debated. It is unclear ho...

This study reports on the cosmogenic 36Cl dating of two normal fault scarps in western Turkey, that of the Manastır and Mugırtepe faults, beyond existing historical records. These faults are elements of the western Manisa Fault Zone (MFZ) in the seismically active Gediz Graben. Our modeling revealed that the Manastır fault underwent at least two su...

Mid-latitude mountain glaciers sensitively respond to local summer temperature changes. Chronologies of past glacier fluctuations based on the investigation of glacial landforms therefore allows for a better understanding of warm-season climate variability at local scale. In this study, we focus on the Holocene, the current interglacial of the last...

The Sun sporadically produces eruptive events leading to intense fluxes of solar energetic particles (SEPs) that dramatically disrupt the near-Earth radiation environment. Such events are directly studied for the last decades but little is known about the occurrence and magnitude of rare, extreme SEP events. Presently, a few events that produced me...

The evolution of the Swiss landscape during the Quaternary Period over the past 2.6 million years is controlled by multiple glaciations and deglaciations with at least 15 drastic environmental changes between glacier advances (with yearly average temperatures of –16° compared with today) and warm phases (with yearly average temperatures of +2° comp...

The glacial landforms at Wangen an der Aare provide a footprint of the extent of the Valais (Rhone) glacier during the Last Glacial Maximum. The early studies of the region played a key role in development of the glacial theory during the early nineteenth century. The Valais glacier advanced into the region several times leaving evidence of its pre...

The landscape of the Swiss National Park (SNP) is an area of unique beauty within the morphological systems of the Swiss Alps. This is due to bedrock lithology and its deformation history: the Austroalpine facies and structures are restricted to the southeasternmost corner of the country. The morphologically dominant and most visible rock type in t...

The analysis of the stable isotope of the tree-ring cellulose is an important tool for paleo climatic investigations. Long tree-ring chronologies consist predominantly of oaks and conifers in Europe, including larch trees (Larix decidua) and cembran pines (Pinus cembra) that form very long tree ring chronologies in the Alps and grow at the treeline...

A recent analysis of stable isotopes of the Alpine Holocene Tree-Ring Dataset, consisting of samples from 192 larch and cembran pine trees, revealed that δD and δ18O exhibit no trends in adult trees, but evidence trends in the juvenile period of the first 100 years of cambial age. In this work we applied the Spearman statistical analysis on differe...

Stable isotopes in tree-ring cellulose are important tools for climatic reconstructions even though their interpretation could be challenging due to nonclimate signals, primarily those related to tree aging. Previous studies on the presence of tree-age-related trends during juvenile as well as adult growth phases in δD, δ18O, and δ13C time series y...

Stable isotopes in tree-ring cellulose are important tools for climatic reconstructions even though their interpretation could be challenging due to nonclimate signals, primarily those related to tree aging. Previous studies on the presence of tree-age-related trends during juvenile as well as adult growth phases in δD, δ18O, and δ13C time series y...

Abstract. Stable isotopes in tree-ring cellulose are important tools for climatic reconstructions even though their interpretation could be challenging due to non-climate signals, primarily those related to tree ageing. Previous studies on the presence of tree-age related trends during juvenile as well as adult growth phases in δD, δ¹⁸O...

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The northern Swiss Alpine Foreland exemplifies a highly transient landscape characterized by multiple knickzones along the trunk valleys and distinct bedrock straths at their junction with tributary valleys. This landscape has evolved as a result of fast base level changes in response to repeated glaciations during the Quaternary. As the archives r...

Our new dataset from the Rivoli‐Avigliana end‐moraine system, the westernmost amphitheatre of the Italian Alps, provides an important step towards understanding foreland‐reaching glaciations before and during the Last Glacial Maximum (LGM) in the Western Alps. 10Be data from six boulders in pre‐LGM deposits gave ages between 26.8 ± 2.1 and 41.2 ± 1...

Cellulose content (CC (%)) in tree rings is usually utilised as a tool to control the quality of the α-cellulose extraction from tree rings in the preparation of stable-isotope analysis in wooden tissues. Reported amounts of CC (%) are often limited to mean values per tree. For the first time, CC (%) series from two high-Alpine species, Larix decid...

To develop a more precise understanding of Alpine glacier fluctuations during the Holocene, the glacier forefields of the Triftjegletscher and the Oberseegletscher east of Zermatt in the Valais Alps, Switzerland, were investigated. A multidisciplinary approach of detailed geological and geomorphological field mapping combined with ¹⁰Be exposure and...

We report results from a comprehensive surface exposure dating campaign in eastern Finnmark, located in the northernmost part of Norway and close to the Norwegian-Russian border. This is a palaeo-glaciologically important region as it sits near the proposed border-zone between the former Scandinavian and Barents Sea Ice Sheets. However, until now t...

During the cold periods in Quaternary, equilibrium-line altitude (ELA) decreased which caused valley glaciers to advance. To the contrary, the tongues of glaciers retreated during the warm periods. Quaternary glacier fluctuations were also recorded from Turkish mountains. Recently, the chronology of Late Quaternary advances in the northern and west...

The Quaternary stratigraphy of the Alpine Foreland consists of distinct terrace levels, which have been assigned to four morphostratigraphic units: Höhere (Higher) Deckenschotter, Tiefere (Lower) Deckenschotter, Hochterrasse (High Terrace) and Niederterrasse (Lower Terrace). Here, we focus on the terrace gravels at Hohle Gasse, SSE of Pratteln near...

In this study, we use isochron-burial dating to date the Swiss Deckenschotter, the oldest Quaternary deposits of the northern Alpine Foreland. Concentrations of cosmogenic 10Be and 26Al in individual clasts from a single stratigraphic horizon can be used to calculate an isochron-burial age based on an assumed initial ratio and the measured 26Al/10B...

Cellulose content (CC [%]) in tree rings is usually utilized as a tool to control the quality of the α-cellulose extraction from tree-rings in the preparation of stable isotope analysis in wooden tissues. Reported amounts of CC [%] are often limited to mean values per tree. For the first time, CC [%] series from two high Alpine species, Larix decid...

The Koefels rockslide, with a volume of 2-3 km3, involved sliding of predominantly orthogneiss (granitic and augen gneiss) from the Schartle ridge on the west side of Ötztal eastward into the mouth of Horlachtal. The dating of compressed wood fragments found in a tunnel built for a later abandoned waterworks project in the 1960s indicated an early...

Glacier oscillations, especially during the Late Quaternary, have been widely studied and their timing, amplitude and frequency are reconstructed by detailed field mapping and dating techniques such as surface exposure dating. Recently, the chronology of Late Quaternary advances in the northern and western Turkish mountains was reconstructed by cos...

Surface exposure dating with a single cosmogenic nuclide relies on the assumption of simple constant exposure. In contrast, the combination of nuclides with different half-lives or production rate depth profiles allows constraining complex exposure histories. Here we present the systematics of how the combination of ¹⁰Be, in situ ¹⁴C and ³⁶Cl can b...

During the cold periods in Quaternary, equilibrium line altitude decreased and as a result valley glaciers advanced. The vice versa occurred during the warm periods. Quaternary glacier fluctuations had also been recorded in the Turkish mountains. Recently, the chronology of Late Quaternary advances in the northern and western Turkish mountains was...

The landscape evolution of the Swiss Alpine Foreland since the early Pleistocene is of utmost importance for modelling the long-term safety of deep geological repositories for nuclear waste disposal in the northern Alpine Foreland. The oldest Quaternary sediments in the northern foreland are proximal glaciofluvial sediments lying unconformably on T...

10Be depth-profile dating is based on the fact that nuclide production is decreasing as an exponential function of depth. This method requires collecting at least four sediment samples in a vertical profile. The obtained nuclide concentrations are plotted against depth and fitted depth-profiles to the measured dataset. The age is then calculated ba...

The landscape evolution of the Swiss Alpine Foreland since the early Pleistocene is of utmost importance for modelling the long-term safety of deep geological repositories for nuclear waste disposal in the northern Alpine Foreland. The oldest Quaternary sediments in the northern foreland are proximal glaciofluvial sediments lying unconformably on T...

The recently introduced method of isochron-burial dating, employs the fact that the samples from a well-defined single bed in a deposit would have the same post-burial but different pre-burial histories. The analysis of cosmo-genic 10Be and 26Al in such samples enables the modeling of the post-burial component and the determination of the 26Al/10Be...

We combine 10Be surface exposure ages from boulders and bedrock, field observations and measurement of bedrock ice-flow direction indicators with numerical ice surface models to develop a model of the evolution of the Oberhasli area in the central Swiss Alps from the Last Glacial Maximum (LGM) to the early Holocene. Surface exposure ages from bedro...

To reconstruct the timing of Alpine glacier advances onto the Jura Mountains, we sampled 17 Alpine erratic boulders within and beyond the LGM (Last Glacial Maximum) extent of the Valais Glacier along three transect for the analysis of cosmogenic 10Be. Our results indicate at least two advances into the study area in Northwestern Switzerland; one du...

Cosmogenic 10Be and 26Al can be employed to reconstruct the chronology of sediment layers. Accumulation of these can be used to exposure date the sediment layer as the variation of cosmogenic nuclide concentration with depth can be modeled. Decay of 10Be and 26Al in the samples from a well-defined single bed in a deposit enables the modeling of the...

Toros ve Pontid Dağ Kuşakları arasında yeralan Orta Anadolu Platosu (OAP) Dünya'da gözlenen diğer platolara oranla daha küçük (300 x 400 km) ve nispeten daha alçak (∼1 km) olmasına rağmen tektonik, volkanik ve yüzey süreçlerinin karşılıklı etkileşimi bakımından benzerlikler göstermektedir. Türkiye sınırları içinde denize dökülen en uzun nehir (1355...

Glacial maxima and their terminations provide key insights into inter-hemispheric climate dynamics and the coupling of atmosphere, surface and deep ocean, hydrology, and cryosphere, which is fundamental for evaluating the robustness of earth's climate in view of ongoing climate change. The Last Glacial Maximum (LGM, ∼26–19 ka ago) is widely seen as...

We used cosmogenic 10Be and 36Cl to establish the timing of the onset of deglaciation after the Last Glacial Maximum of the Reuss Glacier, one of the piedmont lobes of the Alpine ice cap that reached the northern Alpine foreland in Switzerland. In this study, we sampled erratic boulders both at the frontal position in the foreland (Lenzburg and Woh...

The Swiss Deckenschotter (“cover gravels”) is the oldest Quaternary units in the northern Swiss Alpine Foreland. They are a succession of glaciofluvial gravel layers intercalated with glacial and/or overbank deposits. This lithostratigraphic sequence is called Deckenschotter because it “covers” Molasse or Mesozoic bedrock and forms mesa-type hill-t...

During cold periods in the Quaternary, the global ice volume increased and thus ice sheets expanded and valley glaciers advanced. Glacier oscillations, especially during the Late Quaternary, have been widely studied and their timing, amplitude and frequency are reconstructed by detailed field mapping and dating techniques such as surface exposure d...

The evidence of paleoglaciers provides important information of past climate changes. Especially, mountain glaciers are very sensitive indicators of changes of temperature and precipitation. Our aim is to reconstruct a local chronology of paleoglacier oscillations and to produce interrelationship with different terrestrial datasets of paleoenvironm...

Glacier oscillations, especially during the Late Quaternary, have been widely studied and their timing, amplitude and frequency are reconstructed by detailed field mapping and dating techniques such as surface exposure dating. Late Quaternary advances of Turkish glaciers have been exposure-dated in only ten sites in the northern and western Anatoli...

Our study in the Başyayla Valley in northeastern Anatolia showed evidence of four glacier advances that built terminal and lateral moraines. Surface exposure dating of boulders on these moraines showed that the Maximum Ice Extent (MIE) was asynchronous with the global Last Glacial Maximum (LGM; 22.1 ± 4.3 thousand years; ka). The local MIE took pla...

Mit dem Aufkommen der Glaziologie im 19. Jh. begannen auch die Forschungen zur Rekonstruktion der vergangenen Gletscherschwankungen. Zunächst mussten sich solche Ansätze stark auf die Analyse historischer Dokumente beschränken. Mit den Fortschritten der Naturwissenschaften und vor allem der Datierungsmöglichkeiten im 20. Jh. waren schließlich für d...

The abundant production of in situ cosmogenic 36Cl from potassium renders 36Cl measurements in K-rich rocks or minerals, such as K-feldspars, potentially useful for precisely dating rock surfaces, either in single-nuclide or in multi-nuclide studies, for example combined with 10Be measurements in quartz. However, significant discrepancies in experi...

The amplitude and timing of past glacier culminations are sensitive recorders of key climate events on a regional scale. Precisely dating young moraines using cosmogenic nuclides to investigate Holocene glacier chronologies has proven challenging, but progress in the high-sensitivity 10Be technique has recently been shown to enable the precise dati...

To calibrate the in situ 10Be production rate, we collected surface samples from nine large granitic boulders within the deposits of a rock avalanche that occurred in AD 1717 in the upper Ferret Valley, Mont Blanc Massif, Italy. The 10Be concentrations were extremely low and successfully measured within 10% analytical uncertainty or less. The conce...

Deckenschotter (cover gravels) are Quaternary sediments of the Northern Alpine Foreland, occurring beyond the limit of the Last Glacial Maximum. These sediments are a succession of proximal glaciofluvial gravels, covering Tertiary Molasse or Mesozoic bedrock. Furthermore, the Deckenschotter are topographically distinct and discontinuous archives, ha...

We present the improved performance of the modified in situ cosmogenic 14C extraction system at ETH Zürich. Samples are now processed faster (2 days in total) and are measured with a high analytical precision of usually <2% using the gas ion source of the MICADAS AMS facility. Measurements of the PP-4 standard sample show a good reproducibility and...

We reconstruct the timing of ice flow reconfiguration and deglaciation of the Central Alpine Gotthard Pass, Switzerland, using cosmogenic Be-10 and in situ C-14 surface exposure dating. Combined with mapping of glacial erosional markers, exposure ages of bedrock surfaces reveal progressive glacier downwasting from the maximum LGM ice volume and a g...

In this study, we document glacial deposits and reconstruct the glacial history in the Karagöl valley system in the eastern Uludağ in northwestern Turkey based on 42 cosmogenic 10Be exposure ages from boulders and bedrock. Our results suggest the Last Glacial Maximum (LGM) advance prior to 20.4 ± 1.2 ka and at least three re-advances until 18.6 ± 1...

On 12 September AD 1717, a rock volume larger than 10 million m 3 collapsed onto the Triolet Glacier, mobilized a mass composed of ice and sediment and travelled more than 7 km downvalley in the upper Ferret Valley, Mont Blanc Massif (Italy). This rock avalanche destroyed two small settlements, causing seven casualties and loss of livestock. No det...

The timing and amplitude of changes in the Antarctic ice level are relevant to understanding past climate fluctuations and ongoing changes in the global climate and sea levels. In this study, we present surface exposure ages based on in situ produced cosmogenic 10 Be and 21 Ne in the bedrock samples of glacially eroded relict surfaces from the Deep...

The natural variability of Holocene climate defines the baseline to assess ongoing climate change. Greenland ice-core records indicate warming superimposed by abrupt climate oscil- lations in the early Holocene, followed by a general cooling trend throughout the middle and late Holocene that culminated during the Little Ice Age (LIA). Tropical prec...

a b s t r a c t We present the improved performance of the modified in situ cosmogenic 14 C extraction system at ETH Zürich. Samples are now processed faster (2 days in total) and are measured with a high analytical pre-cision of usually <2% using the gas ion source of the MICADAS AMS facility. Measurements of the PP-4 Ástandard sample show a good...

Lateral moraines are prominent features of glaciated landscapes in high-mountain environments and key landforms in glacier and palaeoclimatic reconstructions, yet, compared to smaller moraines, they have been little studied and several aspects are not well understood. We here present detailed sedimentological results from the lateral moraines of Fi...

Over the course of the next years, we are aiming to combine signals of cosmogenic Be-10, C-14, Al-26 and Cl-36 to constrain depth and rate of glacial erosion at several study sites in the Alps and to determine the timing of local deglaciation. Within this suite of nuclides, the system of Be is the best understood. It is routinely used and often com...

Today's climate of the northern part of the eastern Black Sea Mountains is humid with a mean annual precipitation over 2000 mm. The moisture is directly transported from the Black Sea. Field evidence indicate that this area was glaciated during past. Ice build-up can be therefore explained by a moisture transport system similar to today. Analogous...

Recent re-evaluations of production rates for cosmogenic 10Be now necessitate recalculation of 10Be exposure ages from sites in the Alps that we have studied over the past 20 years. In the Alps we have the unique opportunity to exposure date in well constrained field situations, supported by more than a century and a half of detailed field mapping....