Cosmogenic Nuclides; Paleo Erosion Rates; Climate and Erosion; Andes
Litty Camille, Schlunegger Fritz, Akçar Naki, Lanari Pierre, Christl Marcus, Vockenhuber Christof (2018), Possible climatic controls on the accumulation of Peru's most prominent alluvial fan: The Lima Conglomerate, in
Earth Surface Processes and Landforms, 44(5), 991-1003.
Madella Andrea, Delunel Romain, Akçar Naki, Schlunegger Fritz, Christl Marcus (2018), 10Be-inferred paleo-denudation rates imply that the mid-Miocene western central Andes eroded as slowly as today, in
Scientific Reports, 8(1), 2299-2299.
Litty Camille, Schlunegger Fritz, Akçar Naki, Delunel Romain, Christl Marcus, Vockenhuber Christof (2018), Chronology of alluvial terrace sediment accumulation and incision in the Pativilca Valley, western Peruvian Andes, in
Geomorphology, 315, 45-56.
Litty Camille, Schlunegger Fritz, Viveen Willem (2017), Possible threshold controls on sediment grain properties of Peruvian coastal river basins, in
Earth Surface Dynamics, 5(3), 571-583.
Norton Kevin P., Schlunegger Fritz (2017), Lack of a weathering signal with increased Cenozoic erosion?, in
Terra Nova.
Reber Regina, Delunel Romain, Schlunegger Fritz, Litty Camille, Madella Andrea, Akçar Naki, Christl Marcus (2017), Environmental controls on 10 Be-based catchment-averaged denudation rates along the western margin of the Peruvian Andes, in
Terra Nova.
Schlunegger Fritz, Norton Kevin P., Delunel Romain, Ehlers Todd A., Madella Andrea (2017), Late Miocene increase in precipitation in the Western Cordillera of the Andes between 18–19°S latitudes inferred from shifts in sedimentation patterns, in
Earth and Planetary Science Letters, 462, 157-168.
Litty Camille, Schlunegger Fritz (2017), Controls on Pebbles’ Size and Shape in Streams of the Swiss Alps, in
The Journal of Geology, 125(1), 101-112.
Litty Camille, Lanari Pierre, Burn Marco, Schlunegger Fritz (2016), Climate-controlled shifts in sediment provenance inferred from detrital zircon ages, western Peruvian Andes, in
Geology, 45(1), 59-62.
Madella Andrea, Delunel Romain, Audin Laurence, Schlunegger Fritz (2016), Why is there no Coastal Cordillera at the Arica Bend (Western Central Andes)?, in
Basin Research.
Litty Camille, Duller Robert, Schlunegger Fritz (2016), Paleohydraulic reconstruction of a 40 ka-old terrace sequence implies that water discharge was larger than todayPaleohydraulic Reconstruction in the Pisco Valley, Peru, in
Earth Surface Processes and Landforms, 41(7), 884-898.
Norton K. P., Schlunegger F., Litty C. (2016), On the potential for regolith control of fluvial terrace formation in semi-arid escarpments, in
Earth Surface Dynamics, 4(1), 147-157.
Andrea Madella Romain Delunel Onno Oncken Sönke Szidat Fritz Schlunegger, Transient uplift of a long-term quiescent coast inferred from raised fan delta sediments, in
Lithosphere.
We focus on the western Andean margin between northern Peru and northern Chile where we aim to explore the response of erosion to climate change at orbital to Myr time scales. The climate in the central Andes is characterized by strong north-south and east-west precipitation gradients, has experienced orbital changes in precipitation regimes as documented by variations in lake level highstands on the Altiplano, and has likewise been affected by shifts in the Andean jet in response to the rise of Altiplano. This proposal focuses on the several tens of meters-thick Quaternary cut-and-fill terrace sequences that bear information about orbital-driven changes in erosional regimes, as our previous studies have shown. The applicant has identified five sites between 10S° and 20°S where these terraces will be investigated upon climate-driven changes in modern and paleo erosional patterns and rates. The plan is to: (i) date these archives, (ii) measure (paleo) erosion rates recorded by these deposits, (iii) determine the provence of these deposits, and (iv) improve the age models.The dating of the Quaternary archives will be achieved with in-situ terrestrial cosmogenic nuclides (TCNs). Here, 10Be and 26Al depth-profile and burial-isochron dating techniques yield a chronology where other techniques (optically stimulated luminescence techniques, 14C) have failed to date these archives. To this extent, we have already collected TCN samples at c. 15 sites that we plan to process within the framework of this project. Also at these sites, concentrations of cosmogenic 10Be, 26Al, 21Ne and possibly 3He will be measured to determine the (paleo) erosion rates recorded by the modern stream and Quaternary terrace sediments. A first set of samples was already collected in the framework of the precursory project. They need to be processed in the laboratory and measured for the concentrations of the TCNs in quartz and pyroxene minerals. We have additionally sampled an 13-11 Ma-old section in northern Chile to measure paleo erosion rates with cosmogenic 21Ne and 3He. This sequence chronicles a sedimentological change from debris flow processes before 10 Ma to fluvial processes thereafter. This implies that the availability of water and the related rainfall patterns have changed possibly in response to the rise of the Altiplano plateau. The application of cosmogenic 21Ne and 3He to these deposits will allow us to ascertain whether this environmental shift had a measurable impact on the paleo erosion rates. Our previous studies have shown that the provenance of the sediments most likely changed as orbital climate variations were associated by shifts in the location where fast erosion has occurred. Because the headwaters and the trunk valley reaches of the Andean expose different lithologies, any shifts in erosional sites will release material with a different petrographic composition, which we plan to quantify with provenance tracing methods.