Articles | Volume 4, issue 4
Research article 04 Nov 2016
Research article | 04 Nov 2016
Influence of topography and human activity on apparent in situ 10Be-derived erosion rates in Yunnan, SW China
Amanda H. Schmidt et al.
No articles found.
Greg Balco, Benjamin D. DeJong, John C. Ridge, Paul R. Bierman, and Dylan H. Rood
Geochronology, 3, 1–33,Short summary
The North American Varve Chronology (NAVC) is a sequence of 5659 annual sedimentary layers that were deposited in proglacial lakes adjacent to the retreating Laurentide Ice Sheet ca. 12 500–18 200 years ago. We attempt to synchronize this record with Greenland ice core and other climate records that cover the same time period by detecting variations in global fallout of atmospherically produced beryllium-10 in NAVC sediments.
Martin D. Hurst, Dylan H. Rood, and Michael A. Ellis
Earth Surf. Dynam., 5, 67–84,Short summary
Beryllium-10 is a rare isotope that only forms near to the Earth surface, allowing rock surfaces to be dated. In this paper we develop a numerical model for the evolution of shore platforms and associated 10Be concentrations to explore the potential for this method to reveal long-term rates of sea cliff retreat. Tides, sea level, cliffs and beaches all modify how rapidly 10Be accumulates on the shore platform, but there is great potential to measure rates of cliff retreat and platform erosion.
Related subject area
Cross-cutting themes: Geochronology applied to establish timing and rates of Earth surface processesModelling the effects of ice transport and sediment sources on the form of detrital thermochronological age probability distributions from glacial settingsHolocene sea-level change on the central coast of Bohai Bay, ChinaOSL rock surface exposure dating as a novel approach for reconstructing transport histories of coastal boulders over decadal to centennial timescalesThe role of frost cracking in local denudation of steep Alpine rockwalls over millennia (Eiger, Switzerland)Early-to-mid Miocene erosion rates inferred from pre-Dead Sea rift Hazeva River fluvial chert pebbles using cosmogenic 21NeDenudation systematics inferred from in situ cosmogenic 10Be concentrations in fine (50–100 µm) and medium (100–250 µm) sediments of the Var River basin, southern French AlpsMillennial-scale denudation rates in the Himalaya of Far Western NepalInferring the timing of abandonment of aggraded alluvial surfaces dated with cosmogenic nuclidesSeeking enlightenment of fluvial sediment pathways by optically stimulated luminescence signal bleaching of river sediments and deltaic depositsCosmogenic 10Be in river sediment: where grain size matters and whyDating and morpho-stratigraphy of uplifted marine terraces in the Makran subduction zone (Iran)How steady are steady-state mountain belts? A reexamination of the Olympic Mountains (Washington state, USA)Short communication: Increasing vertical attenuation length of cosmogenic nuclide production on steep slopes negates topographic shielding corrections for catchment erosion ratesGlacial dynamics in pre-Alpine narrow valleys during the Last Glacial Maximum inferred by lowland fluvial records (northeast Italy)Reconstructing lateral migration rates in meandering systems – a novel Bayesian approach combining optically stimulated luminescence (OSL) dating and historical mapsTectonic controls of Holocene erosion in a glaciated orogenExtracting information on the spatial variability in erosion rate stored in detrital cooling age distributions in river sandsU–Th and 10Be constraints on sediment recycling in proglacial settings, Lago Buenos Aires, PatagoniaThe CAIRN method: automated, reproducible calculation of catchment-averaged denudation rates from cosmogenic nuclide concentrationsDenudation rates across the Pamir based on 10Be concentrations in fluvial sediments: dominance of topographic over climatic factorsTectonic and climatic controls on the Chuquibamba landslide (western Andes, southern Peru)Re-evaluating luminescence burial doses and bleaching of fluvial deposits using Bayesian computational statisticsA linear inversion method to infer exhumation rates in space and time from thermochronometric data
Maxime Bernard, Philippe Steer, Kerry Gallagher, and David Lundbek Egholm
Earth Surf. Dynam., 8, 931–953,Short summary
Detrital thermochronometric age distributions of frontal moraines have the potential to retrieve ice erosion patterns. However, modelling erosion and sediment transport by the Tiedemann Glacier ice shows that ice velocity, the source of sediment, and ice flow patterns affect age distribution shape by delaying sediment transfer. Local sampling of frontal moraine can represent only a limited part of the catchment area and thus lead to a biased estimation of the spatial distribution of erosion.
Fu Wang, Yongqiang Zong, Barbara Mauz, Jianfen Li, Jing Fang, Lizhu Tian, Yongsheng Chen, Zhiwen Shang, Xingyu Jiang, Giorgio Spada, and Daniele Melini
Earth Surf. Dynam., 8, 679–693,Short summary
Our new Holocene sea level curve is not only different to previously published data but also different to global glacio-isostatic adjustment (GIA) models. We see that as soon as ice melting has ceased, local processes control shoreline migration and coast evolution. This indicates that more emphasis should be placed on regional coast and sea-level change modelling under a global future of rising sea level as local government needs more specific and effective advice to deal with coastal flooding.
Dominik Brill, Simon Matthias May, Nadia Mhammdi, Georgina King, Christoph Burow, Dennis Wolf, Anja Zander, Benjamin Lehmann, and Helmut Brückner
Earth Surf. Dynam. Discuss.,
Revised manuscript under review for ESurfShort summary
Wave-transported boulders are important records for storm and tsunami impact over geological timescales. Their use for hazard assessment requires chronological information. We investigated the potential of a new dating technique, luminescence rock surface exposure dating, for estimating transport ages of wave-emplaced boulders. Our results show that the new approach may provide chronological information over decadal to millennial timescales for boulders not datable by any other method so far.
David Mair, Alessandro Lechmann, Romain Delunel, Serdar Yeşilyurt, Dmitry Tikhomirov, Christof Vockenhuber, Marcus Christl, Naki Akçar, and Fritz Schlunegger
Earth Surf. Dynam., 8, 637–659,
Michal Ben-Israel, Ari Matmon, Alan J. Hidy, Yoav Avni, and Greg Balco
Earth Surf. Dynam., 8, 289–301,Short summary
Early-to-mid Miocene erosion rates were inferred using cosmogenic 21Ne measured in chert pebbles transported by the Miocene Hazeva River (~ 18 Ma). Miocene erosion rates are faster compared to Quaternary rates in the region. Faster Miocene erosion rates could be due to a response to topographic changes brought on by tectonic uplift, wetter climate in the region during the Miocene, or a combination of both.
Apolline Mariotti, Pierre-Henri Blard, Julien Charreau, Carole Petit, Stéphane Molliex, and the ASTER Team
Earth Surf. Dynam., 7, 1059–1074,Short summary
This work is the first assessment of the suitability of the in situ 10Be method to determine denudation rates from fine (50–100 μm) detrital quartz at the watershed scale. This method is used worldwide to determine denudation rates from sandy sediments (250 μm-1 mm). We show that in the Var catchment fine-grained sediments (50–100 μm) are suited to the 10Be method, which is vital for future applications of 10Be in sedimentary archives such as offshore sediments.
Lujendra Ojha, Ken L. Ferrier, and Tank Ojha
Earth Surf. Dynam., 7, 969–987,
Mitch K. D'Arcy, Taylor F. Schildgen, Jens M. Turowski, and Pedro DiNezio
Earth Surf. Dynam., 7, 755–771,Short summary
The age of formation of sedimentary deposits is often interpreted to record information about past environmental changes. Here, we show that the timing of abandonment of surfaces also provides valuable information. We derive a new set of equations that can be used to estimate when a sedimentary surface was abandoned based on what is known about its activity from surface dating. Estimates of abandonment age can benefit a variety of geomorphic analyses, which we illustrate with a case study.
Elizabeth L. Chamberlain and Jakob Wallinga
Earth Surf. Dynam., 7, 723–736,Short summary
Sand and mud may take many different pathways within a river as they travel from inland to the coast. During the trip, grains may be exposed to daylight, resetting a signal trapped within certain minerals. The signal can be measured in a laboratory to estimate the time since last light exposure. Here, we measure the trapped signal of sand and mud grains from the Mississippi River and its banks. We use this information to infer sediment pathways. Such knowledge is useful for delta management.
Renee van Dongen, Dirk Scherler, Hella Wittmann, and Friedhelm von Blanckenburg
Earth Surf. Dynam., 7, 393–410,Short summary
The concentration of cosmogenic 10Be is typically measured in the sand fraction of river sediment to estimate catchment-average erosion rates. Using the sand fraction in catchments where the 10Be concentrations differ per grain size could potentially result in biased erosion rates. In this study we investigated the occurrence and causes of grain size-dependent 10Be concentrations and identified the types of catchments which are sensitive to biased catchment-average erosion rates.
Raphaël Normand, Guy Simpson, Frédéric Herman, Rabiul Haque Biswas, Abbas Bahroudi, and Bastian Schneider
Earth Surf. Dynam., 7, 321–344,Short summary
We studied and mapped uplifted marine terraces in southern Iran that are part of the Makran subduction zone. Our results show that most exposed terraces were formed in the last 35 000–250 000 years. Based on their altitude and the paleo sea-level, we derive surface uplift rates of 0.05–5 mm yr−1. The marine terraces, tilted with a short wavelength of 20–30 km, indicate a heterogeneous accumulation of deformation in the overriding plate.
Lorenz Michel, Christoph Glotzbach, Sarah Falkowski, Byron A. Adams, and Todd A. Ehlers
Earth Surf. Dynam., 7, 275–299,Short summary
Mountain-building processes are often investigated by assuming a steady state, meaning the balance between opposing forces, like mass influx and mass outflux. This work shows that the Olympic Mountains are in flux steady state on long timescales (i.e., 14 Myr), but the flux steady state could be disturbed on shorter timescales, especially by the Plio–Pleistocene glaciation. The contribution highlights the temporally nonsteady evolution of mountain ranges.
Roman A. DiBiase
Earth Surf. Dynam., 6, 923–931,
Sandro Rossato, Anna Carraro, Giovanni Monegato, Paolo Mozzi, and Fabio Tateo
Earth Surf. Dynam., 6, 809–828,Short summary
Glaciations may induce significant changes in the catchments of major sedimentary systems over time, even during a single phase. The rugged morphology of Alpine valleys may slow, block or divert glacial tongues. This conclusion arises from reconstructions made regarding the dynamics of the Brenta glacial system (northeast Italy). These reconstructions included sediment analysis techniques on the related alluvial stratigraphic record and mapping of in-valley glacial/glaciofluvial remnants.
Cindy Quik and Jakob Wallinga
Earth Surf. Dynam., 6, 705–721,Short summary
Identifying contemporary river migration rates is often based on aerial photos or recent topographical maps. Here, we propose to use river sediments as an archive to look further back in time using optically stimulated luminescence (OSL) dating and develop a modelling procedure for the joint analysis of dating results and historical maps. The procedure is applied to the Overijsselse Vecht river in The Netherlands, and we show that the river migrated with 0.9–2.6 m yr−1 between 1400 and 1900 CE.
Byron A. Adams and Todd A. Ehlers
Earth Surf. Dynam., 6, 595–610,Short summary
Where alpine glaciers were active in the past, they have created scenic landscapes that are likely in the process of morphing back into a form that it more stable with today's climate regime and tectonic forces. By looking at older erosion rates from before the time of large alpine glaciers and erosion rates since deglaciation in the Olympic Mountains (USA), we find that the topography and erosion rates have not drastically changed despite the impressive glacial valleys that have been carved.
Jean Braun, Lorenzo Gemignani, and Peter van der Beek
Earth Surf. Dynam., 6, 257–270,Short summary
We present a new method to interpret a type of data that geologists obtained by dating minerals in river sand samples. We show that such data contain information about the spatial distribution of the erosion rate (wear of surface rocks by natural processes such as river incision, land sliding or weathering) in the regions neighboring the river. This is important to understand the nature and efficiency of the processes responsible for surface erosion in mountain belts.
Antoine Cogez, Frédéric Herman, Éric Pelt, Thierry Reuschlé, Gilles Morvan, Christopher M. Darvill, Kevin P. Norton, Marcus Christl, Lena Märki, and François Chabaux
Earth Surf. Dynam., 6, 121–140,Short summary
Sediments produced by glaciers are transported by rivers and wind toward the ocean. During their journey, these sediments are weathered, and we know that this has an impact on climate. One key factor is time, but the duration of this journey is largely unknown. We were able to measure the average time that sediment spends only in the glacial area. This time is 100–200 kyr, which is long and allows a lot of processes to act on sediments during their journey.
Simon Marius Mudd, Marie-Alice Harel, Martin D. Hurst, Stuart W. D. Grieve, and Shasta M. Marrero
Earth Surf. Dynam., 4, 655–674,Short summary
Cosmogenic nuclide concentrations are widely used to calculate catchment-averaged denudation rates. Despite their widespread use, there is currently no open source method for calculating such rates, and the methods used to calculate catchment-averaged denudation rates vary widely between studies. Here we present an automated, open-source method for calculating basin averaged denudation rates, which may be used as a stand-alone calculator or as a front end to popular online calculators.
M. C. Fuchs, R. Gloaguen, S. Merchel, E. Pohl, V. A. Sulaymonova, C. Andermann, and G. Rugel
Earth Surf. Dynam., 3, 423–439,
A. Margirier, L. Audin, J. Carcaillet, S. Schwartz, and C. Benavente
Earth Surf. Dynam., 3, 281–289,Short summary
This study deals with the control of crustal tectonic activity and Altiplano climatic fluctuations in the evolution of the arid western Andes. Based on geomorphic analysis coupled with terrestrial cosmogenic nuclide investigation, we point out the role of active faulting and wet events in the development of the Chuquibamba landslide (southern Peru). Our main outcome is that the last major debris flow coincides in time with the Ouki wet climatic event identified on the Altiplano.
A. C. Cunningham, J. Wallinga, N. Hobo, A. J. Versendaal, B. Makaske, and H. Middelkoop
Earth Surf. Dynam., 3, 55–65,Short summary
Rivers transport sediment from mountains to coast, but on the way sediment is trapped and re-eroded multiple times. We looked at Rhine river sediments to see if they preserve evidence of how geomorphic variables have changed over time. We found that measured signals potentially relate to water level and river management practices. These relationships can be treated as hypotheses to guide further research, and our statistical approach will increase the utility of research in this field.
M. Fox, F. Herman, S. D. Willett, and D. A. May
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In order to test the assumption that erosion rates derived from Be-10 are not affected by increases in erosion due to contemporary agricultural land use, we measured erosion rates in three tributaries of the Mekong River. We find that in the most heavily agricultural landscapes, the apparent long-term erosion rate correlates best with measures of modern land use, suggesting that agriculture has eroded below the mixed layer and is affecting apparent erosion rates derived from Be-10.
In order to test the assumption that erosion rates derived from Be-10 are not affected by...