Erosion patterns in the Changjiang (Yangtze River) catchment revealed by bulk-sample versus single-mineral provenance budgets

Vezzoli, Giovanni; Garzanti, Eduardo; Limonta, Mara; Andó, Sergio; Yang, Shouye

doi:10.1016/j.geomorph.2016.02.031

Cited by 67 publications

(61 citation statements)

References 84 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This implies that the choice of used provenance tools should depend on the geological composition of the hinterland. (2) To assess if mineral abundance in the Major tributaries of the Yangtze River causes the dominance of the Dadu River muscovites in the lower Yangtze, we compiled mineral fertility data (mica and zircon) from Vezzoli et al [45]. Figure 5 shows that the concentration of mica in modern sediment of the Dadu River is much lower than that of the Han River and higher than the Jialing and Jinsha rivers.…”

Section: Factors Related To the Difference In Zircon And Muscovite Simentioning

confidence: 99%

Comparison of Detrital Zircon U-Pb and Muscovite 40Ar/39Ar Ages in the Yangtze Sediment: Implications for Provenance Studies

et al. 2020

View full text Add to dashboard Cite

Detrital zircon U-Pb and muscovite 40Ar/39Ar dating are useful tools for investigating sediment provenance and regional tectonic histories. However, the two types of data from same sample do not necessarily give consistent results. Here, we compare published detrital muscovite 40Ar/39Ar and zircon U-Pb ages of modern sands from the Yangtze River to reveal potential factors controlling differences in their provenance age signals. Detrital muscovite 40Ar/39Ar ages of the major tributaries and main trunk suggest that the Dadu River is a dominant sediment contributor to the lower Yangtze. However, detrital zircon data suggest that the Yalong, Dadu, and Min rivers are the most important sediment suppliers. This difference could be caused by combined effects of lower reaches dilution, laser spot location on zircons and difference in closure temperature and durability between muscovite and zircon. The bias caused by sediment laser spot targeting a core or rim of zircon and zircon reworking should be considered in provenance studies.

show abstract

Section: Factors Related To the Difference In Zircon And Muscovite Simentioning

confidence: 99%

Comparison of Detrital Zircon U-Pb and Muscovite 40Ar/39Ar Ages in the Yangtze Sediment: Implications for Provenance Studies

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Bedrock data, however, are seldom distributed evenly throughout an entire orogen or continental block. Detrital geochronology may thus help us to achieve a complete coverage of entire regions, to identify sources overlooked by bedrock geochronology, and to assess the relative importance of crustal-growth episodes provided that mineral fertilities and erosion rates in different sources are taken into due account (Moecher & Samson, 2006;Vezzoli, Garzanti, Limonta, And o, & Yang, 2016).…”

Section: Introductionmentioning

confidence: 99%

The zircon story of the Nile: Time‐structure maps of source rocks and discontinuous propagation of detrital signals

et al. 2018

Self Cite

View full text Add to dashboard Cite

A new dimension has recently been added to provenance analysis by the rapid development of detrital‐geochronology techniques. The application of any dating method to sediments allows the definition of a unique age pattern of parent rocks, a “time structure” that represents an essential complement to the information on their lithological structure obtained by traditional petrographic and mineralogical methods. This detrital‐geochronology study illustrates the distribution of U‐Pb zircon ages in all parts of the Nile catchment from its equatorial headwaters to the Delta, and surveys how the provenance signal is formed, transmitted, and modified along this huge sediment‐routing system. Age‐spectra obtained by targeting specific parts of zircon grains after cathodo‐luminesce imaging and by our Automated Phase Mapping + LAICPMS “blind‐dating strategy” were compared. The former approach emphasises specific magmatic or metamorphic events in source areas, whereas the latter aims at minimising selection bias and focuses on consistency among samples. Grain‐size and hydraulic‐sorting controls were also checked, but found to have only a minor effect on zircon‐age distributions. The trimodal age spectrum of Kagera zircons sourced from the rift highlands of Burundi and Rwanda, characterised by prominent late Neoarchean (Aruan) and mid‐Mesoproterozoic (Kibaran) peaks with a wider mid‐Palaeoproterozoic (Ubendian) cluster, is lost in the Lake Victoria sediment sink. The sharp unimodal Aruan peak displayed by zircon grains in both Victoria and Albert Nile is supplemented and finally superseded by Neoproterozoic grains across the vast marshlands of South Sudan, where detritus produced in equatorial regions is eventually stored. All Nile tributaries in Sudan and Egypt carry zircon grains yielding predominantly Neoproterozoic ages, with a major peak around 0.6 Ga associated with clusters around 0.8 and 1.0 Ga. A few Oligocene zircons represent the key diagnostic feature of Ethiopian provenance, the Ariadne's golden thread that allowed retracing the palaeo‐Nile to its Ethiopian sources back in the Oligocene. The Nile presents a text‐book case of discontinuous transmission of provenance signals along a segmented ultra‐long drainage system. Zircon‐age fingerprints as well as all other detrital signatures are lost repeatedly in large Ugandan lakes, reconstituted or replaced, lost again in the vast marshlands of South Sudan, and finally homogenised downstream from Ethiopia and Sudan to the Mediterranean Sea.

show abstract

“…These size fractions were wet-sieved through 125, 63, and 32 µm nylon meshes, respectively. After drying in the oven with a temperature of <40 • C, the very fine sand and coarse silt fractions were then put into a sodium polytungstate solution (2.90 kg/dm 3 at 20 • C; e.g., [5,21,28]) and heavy minerals were separated from the light fraction by the gravity separation method (e.g., [14,29]). The content of the heavy minerals (HMC) is calculated as the total mass of the heavy mineral fraction contained in the analyzed fraction [30].…”

Section: Methodsmentioning

confidence: 99%

“…The pre-dam (Three Gorges Dam) sediment yield of the Changjiang River was >300 × 10 6 tons per year, whereas, at present, it is~120 × 10 6 tons [4]. The reconstruction of the source and distribution patterns of the delta sediments can help to unravel the history of erosion processes, source area characteristics, and the factors controlling and determining the production (source), transport, dispersal and accumulation (sink), and reworking (number of burial-erosion cycles during sediment transport) at different temporal and spatial scales [5][6][7].…”

Section: Introductionmentioning

confidence: 99%

The Chemical Composition and Surface Texture of Transparent Heavy Minerals from Core LQ24 in the Changjiang Delta

et al. 2019

View full text Add to dashboard Cite

The assessment of textural and compositional modifications of detrital sediments is required to reconstruct past source to sink dynamics. The Changjiang Delta is an ideal location to study the sedimentary environment from the Pliocene to Quaternary transition. In the present study, we aim to decipher the response of heavy minerals to mechanical wear and chemical weathering since the Pliocene. With the application of a scanning electron microscope and an electron probe, the geochemistry and surface texture of different heavy minerals (amphibole, epidote, and tourmaline groups) with grain-size fractions of 32–63 µm and 63–125 µm were studied. The result shows that the surface texture of unstable minerals (amphibole, epidote) changed under strong chemical weathering in the Pliocene sediments. By contrast, unstable minerals of the Pleistocene sediments are relatively fresh and similar to those of the modern Changjiang sediment. The stable mineral tourmaline does not exhibit morphology changes in different chemical weathering conditions. No effect of grain size on geochemical composition is noticed. The single minerals of very fine sand and coarse silt show similar geochemical and morphological features. The integration of mineralogy, geochemical data, and grain size parameters yield a more precise understanding of the physical and chemical response of heavy minerals to different weathering conditions. The outcome of the study is also helpful in deciphering sediment provenance changes and environmental changes in the Changjiang basin.

show abstract

Erosion patterns in the Changjiang (Yangtze River) catchment revealed by bulk-sample versus single-mineral provenance budgets

Cited by 67 publications

References 84 publications

Comparison of Detrital Zircon U-Pb and Muscovite 40Ar/39Ar Ages in the Yangtze Sediment: Implications for Provenance Studies

Comparison of Detrital Zircon U-Pb and Muscovite 40Ar/39Ar Ages in the Yangtze Sediment: Implications for Provenance Studies

The zircon story of the Nile: Time‐structure maps of source rocks and discontinuous propagation of detrital signals

The Chemical Composition and Surface Texture of Transparent Heavy Minerals from Core LQ24 in the Changjiang Delta

Contact Info

Product

Resources

About