Paleo-erosion rates in Central Asia since 9Ma: A transient increase at the onset of Quaternary glaciations?

Charreau, Julien; Blard, Pierre‐Henri; Puchol, Nicolas; Avouac, Jean Philippe; Lallier-Vergès, Élisabeth; Bourlès, Didier; Braucher, Régis; Gallaud, Audrey; Finkel, Robert C.; Jolivet, Marc; Chen, Yan; Roy, Pascal Le

doi:10.1016/j.epsl.2011.01.018

Cited by 102 publications

(160 citation statements)

References 60 publications

Supporting

Mentioning

141

Contrasting

Unclassified

Order By: Relevance

“…Samples for measurement of cosmogenic 10 Be were collected from sandstones and conglomerates exposed at the base of 3.5-to 6-m-high road cuts to minimize modern cosmogenic nuclide production that could skew paleo-erosion rate estimates. Our approach to estimating paleo-erosion rates in foreland sediments is similar to that originally described by Charreau et al (37) and also applied in more recent studies (38,39). Measured 10 Be represents the sum of at least three components:…”

Section: Study Area and Methodsmentioning

confidence: 70%

“…Because erosion rate in semiarid watersheds of the central Andes is primarily correlated with precipitation (36), transient excursions in erosion rate over <400,000-y timescales should be a robust proxy for paleoprecipitation. Erosion rates are estimated by measuring cosmogenic 10 Be in ancient fluvial sediments deposited in foreland basin sequences, which record the erosion rate in their source watersheds (37)(38)(39). This approach yields a powerful proxy because it integrates landscape processes over a large region (10 4 -10 5 km 2 ) and provides a continuous record that can be precisely dated using magnetostratigraphy and tephrachronology.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Mio-Pliocene aridity in the south-central Andes associated with Southern Hemisphere cold periods

Amidon

Fisher

Burbank

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Although Earth’s climate history is best known through marine records, the corresponding continental climatic conditions drive the evolution of terrestrial life. Continental conditions during the latest Miocene are of particular interest because global faunal turnover is roughly synchronous with a period of global glaciation from ∼6.2–5.5 Ma and with the Messinian Salinity Crisis from ∼6.0–5.3 Ma. Despite the climatic and ecological significance of this period, the continental climatic conditions associated with it remain unclear. We address this question using erosion rates of ancient watersheds to constrain Mio-Pliocene climatic conditions in the south-central Andes near 30° S. Our results show two slowdowns in erosion rate, one from ∼6.1–5.2 Ma and another from 3.6 to 3.3 Ma, which we attribute to periods of continental aridity. This view is supported by synchrony with other regional proxies for aridity and with the timing of glacial ‟cold” periods as recorded by marine proxies, such as the M2 isotope excursion. We thus conclude that aridity in the south-central Andes is associated with cold periods at high southern latitudes, perhaps due to a northward migration of the Southern Hemisphere westerlies, which disrupted the South American Low Level Jet that delivers moisture to southeastern South America. Colder glacial periods, and possibly associated reductions in atmospheric CO2, thus seem to be an important driver of Mio-Pliocene ecological transitions in the central Andes. Finally, this study demonstrates that paleo-erosion rates can be a powerful proxy for ancient continental climates that lie beyond the reach of most lacustrine and glacial archives.

show abstract

Section: Study Area and Methodsmentioning

confidence: 70%

mentioning

confidence: 99%

Mio-Pliocene aridity in the south-central Andes associated with Southern Hemisphere cold periods

Amidon

Fisher

Burbank

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…This is likely to be reinforced in regions where overdeepened basins prevent the efficient removal of subglacial debris (Cook and Swift, 2012). In this instance, the intensity of erosion (and sediment production) is likely to peak during the initial transition from a largely fluvial to glacial landscape (Charreau et al, 2011) and diminish with time thereafter. (vi) Where the magnitude of climatic deterioration increases from one glacial maximum to the next (i.e., lowering of ELA), erosional feedback is likely to be of limited importance.…”

Section: Confounding Factorsmentioning

confidence: 99%

“…(iv) Basin uplift between phases of glaciation can act to counter glacial erosional feedback. (v) As a landscape becomes tuned to glacial occupation, the extent to which glaciers deepen/erode their basins is likely to diminish (e.g., Charreau et al, 2011;Herman et al, 2011). This is likely to be reinforced in regions where overdeepened basins prevent the efficient removal of subglacial debris (Cook and Swift, 2012).…”

Section: Confounding Factorsmentioning

confidence: 99%

A review of topographic controls on moraine distribution

2014

View full text Add to dashboard Cite

Ice-marginal moraines are often used to reconstruct the dimensions of former ice masses, which are then used as proxies for palaeoclimate. This approach relies on the assumption that the distribution of moraines in the modern landscape is an accurate reflection of former ice margin positions during climatically controlled periods of ice margin stability. However, the validity of this assumption is open to question, as a number of additional, nonclimatic factors are known to influence moraine distribution. This review considers the role played by topography in this process, with specific focus on moraine formation, preservation, and ease of identification (topoclimatic controls are not considered). Published literature indicates that the importance of topography in regulating moraine distribution varies spatially, temporally, and as a function of the ice mass type responsible for moraine deposition. In particular, in the case of ice sheets and ice caps ( > 1000 km 2 ), one potentially important topographic control on where in a landscape moraines are deposited is erosional feedback, whereby subglacial erosion causes ice masses to become less extensive over successive glacial cycles. For the marine-terminating outlets of such ice masses, fjord geometry also exerts a strong control on where moraines are deposited, promoting their deposition in proximity to valley narrowings, bends, bifurcations, where basins are shallow, and/or in the vicinity of topographic bumps. Moraines formed at the margins of ice sheets and ice caps are likely to be large and readily identifiable in the modern landscape. In the case of icefields and valley glaciers (10-1000 km 2 ), erosional feedback may well play some role in regulating where moraines are deposited, but other factors, including variations in accumulation area topography and the propensity for moraines to form at topographic pinning points, are also likely to be important. This is particularly relevant where land-terminating glaciers extend into piedmont zones (unconfined plains, adjacent to mountain ranges) where large and readily identifiable moraines can be deposited. In the case of cirque glaciers (< 10 km 2 ), erosional feedback is less important, but factors such as topographic controls on the accumulation of redistributed snow and ice and the availability of surface debris, regulate glacier dimensions and thereby determine where moraines are deposited. In such cases, moraines are likely to be small and particularly susceptible to post-depositional modification, sometimes making them difficult to identify in the modern landscape. Based on this review, we suggest that, despite often being difficult to identify, quantify, and mitigate, topographic controls on moraine distribution should be explicitly considered when reconstructing the dimensions of palaeoglaciers and that moraines should be judiciously chosen before being used as indirect proxies for palaeoclimate (i.e., palaeoclimatic inferences should only be drawn from moraines when topographic controls on mora...

show abstract

“…Stratigraphic correlation of such sparse data is essential to characterize the history and the properties of sedimentary basins, to determine unit geometries and the volumes of sediment deposited through time, for example. It has, therefore, strong implications for understanding the complex interactions between climate, erosion, sedimentation and tectonics in siliciclastic environments (see for instance Molnar and England (1990); Burbank et al (1996); Métivier et al (1999); Rouby et al (2009);Charreau et al (2011);Guillocheau et al (2012); Bhattacharya et al (2016); Herman and Champagnac (2016);Nicholson et al (2016)). Stratigraphic correlations are also paramount to characterize stratigraphic architectures, their relation to facies distribution and their impact on fluid flow in the subsurface (Jackson et al, 2009;Lallier et al, 2012;Cavero et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

Uncertainty management in stratigraphic well correlation and stratigraphic architectures: A training-based method

Edwards

Lallier

Caumon

et al. 2018

Computers & Geosciences

View full text Add to dashboard Cite

We discuss the sampling and the volumetric impact of stratigraphic correlation uncertainties in basins and reservoirs. From an input set of wells, we evaluate the probability for two stratigraphic units to be associated using an analog stratigraphic model. In the presence of multiple wells, this method sequentially updates a stratigraphic column defining the stratigraphic layering for each possible set of realizations. The resulting correlations are then used to create stratigraphic grids in three dimensions. We apply this method on a set of synthetic wells sampling a forward stratigraphic model built with Dionisos. To perform cross-validation of the method, we introduce a distance comparing the relative geological time of two models for each geographic position, and we compare the models in terms of volumes. Results show the ability of the method to automatically generate stratigraphic correlation scenarios, and also highlight some challenges when sampling stratigraphic uncertainties from multiple wells.

show abstract

Paleo-erosion rates in Central Asia since 9Ma: A transient increase at the onset of Quaternary glaciations?

Cited by 102 publications

References 60 publications

Mio-Pliocene aridity in the south-central Andes associated with Southern Hemisphere cold periods

Mio-Pliocene aridity in the south-central Andes associated with Southern Hemisphere cold periods

A review of topographic controls on moraine distribution

Uncertainty management in stratigraphic well correlation and stratigraphic architectures: A training-based method

Contact Info

Product

Resources

About