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Identifying the degree of luminescence signal bleaching in fluvial sediments from the Inner Mongolian reaches of the Yellow River

1 Introduction OSL dating is now increasingly being used to determine the timing of the deposition of fluvial sediments ( e . g . Wallinga, 2002 ; Jain et al ., 2004 ; Rittenour, 2008 ). This technique has the benefit of being able to directly date the depositional time of the fluvial sediments, using quartz and feldspar (the main constituents of fluvial sediments) as dating materials. The technique has been successfully used to date sediments over timescales ranging from several decades to several hundreds of thousands of years ( e . g . Liu et al

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Geochemistry of Fluvial Sediments from Geregu, Southwest Nigeria

Abstract

Geochemical analysis of fluvial sediments on the banks of River Ero using inductively coupled plasma mass spectrometry illustrates their maturity, provenance and tectonic setting. The analysed sediment samples show low SiO2/Al2O3 ratios of 2.92-2.99 (units FL_A, FL_B and FL_E) and high SiO2/Al2O3 ratios of 4.064-4.852 (units FL_C, FL_D, FL_F and FL_G). Sediments were geochemically classified as shales (units FL_A, FL_B and FL_E) and greywackes (units FL_C, FL_D, FL_F and FL_G). Variability in sediment maturity (FL_F > FL_G >FL_C >FL_D >FL_A > FL_B > FL_E) parallels a decreasing order in the ratios of SiO2/Al2O3 and K2O/Al2O3, as well as the proportion of quartz grains and matrix components. Evidence from Al2O3/TiO2, K2O, Rb, La/Co, Th/Co, Cr/ Th, Th/Cr, La/Th-Hf, Th-Hf-Co and rare earth element contents of sediment samples suggest felsic protoliths of upper continental crust in a passive margin tectonic setting. An insignificant contribution of mafic components from the source is, however, inferred based on the Ni and Cr contents of the sediment samples. Combined Eu anomalies <0.85 and (Gd/Yb)n ratios <2.0 (1.53- 1.82, average 1.65) suggest post-Archean protoliths.

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Heavy metals in fluvial sediments of the Odra River flood plains - introductory research

Heavy metals in fluvial sediments of the Odra River flood plains - introductory research

The article presents the results of research on concentrations of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in fluvial sediment samples collected in the flood plains of the Odra River. The samples were collected from the presently flooded area and from the area which was formerly flooded. The extraction of sediment samples was conducted using aqua regia and four other extractants: 0.01M CaCl2, 0.1M HCl, 0.005M DTPA and 0.02M EDTA. The analysis of the results revealed different concentration values for particular sample collection sites situated along the course of the Odra River. The differentiation of metal concentrations in the investigated samples depending on the extractants was also observed. The concentrations of metals were determined using the technique of atomic absorption spectrometry with flame atomization (F-AAS).

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Comparison of Pipette and Laser Diffraction Methods in Determining the Granulometric Content of Fluvial Sediment Samples

Abstract

Nowadays there is a growing demand for rapid and accurate determination of grain size distribution. The conventional pipette method is time-consuming and provides less detailed data compared to recently introduced methods. However, in Hungarian practice the pipette method is still considered to be the standard one, as there are a long series of measurements, and grain size thresholds used in sedimentology and soil sciences are based on this approach. The aim of our research was to determine the comparability of the laser diffraction method (LDM) with the conventional pipette method (PM), in order to investigate the controversial question on the interchangeability of the two methods. Based on our measurements on some representative fluvial sediment samples, we found that the largest difference in results can be expected in the silty grain size range. However if the main fractions (clay, silt, sand) are considered the methods provided similar very results, and correlation factors were above 0.92. In all, the LDM has a clear advantage because of its speed, reproducibility and fewer possibilities for operator failure.

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Characterisation and OSL dating of modern fluvial sediments in the lower Vistula River: testing the zeroing assumption

A., 2013, Analysis of optical bleaching of OSL signal in sediment quartz. Radiation Measurements, 56: 257–261. DOI: 10.1016/j.radmeas.2013.02.009. PRZEGIĘTKA K.R., CHRUŚCIŃSKA A., 2014, On application of low doses from beta radiation source in OSL retrospective dosimetry. Radiation Physics and Chemistry, 104: 118–123. DOI: 10.1016/j.radphyschem.2014.05.045. SUNDBORG A., 1956, The River Klaralven: a study of fluvial processes. Geografiska Annaler, Series A, Physical Geography, 38: 127–316. SUNDBORG A., 1967, Some aspects on fluvial sediments and

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Infrared stimulated luminescence dating of 19th century fluvial deposits from the upper Rhine River

using MAM of around 500 years ( Fiebig et al .,2009 ). However, it is also important to note that, with a few exceptions (e.g. Porat et al ., 2009 ), almost all previous studies on young fluvial sediments used quartz as it is considered of being less affected by incomplete bleaching than feldspar. Presented here is a case study testing the potential of feldspar IRSL to date very young fluvial deposits from a moderate/low-energy braiding/anastomosing river system from a temperate environmental setting. We took five samples from a sediment sequence that deposited

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Chronology of Cauvery Delta Sediments from Shallow Subsurface Cores Using Elevated-Temperature Post-IR IRSL Dating of Feldspar

(1-4): 367-371, DOI 10.1016/0743-9547(91)90050-8. Chandra S, Rhodes E and Richards KS, 2007. Luminescence dating of late Quaternary fluvial sediments in the Rapti Basin, north-central Gangetic plains. Quaternary International 159: 47-56, DOI 10.1016/j.quaint.2006.08.011. Das S, 1991. Hydrogeological features of deltas and estuarine tracts of India. Memoir of Geological Society of India 22: 183-225. Duller GAT, 2003. Distinguishing quartz and feldspar in single grain luminescence measurements

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Optical Dating of Sediments in Khari River Basin and Slip Rate Along Katrol Hill Fault (KHF), Kachchh, India

Optical Dating of Sediments in Khari River Basin and Slip Rate Along Katrol Hill Fault (KHF), Kachchh, India

In the central region of Mainland Kachchh, Western India, the Katrol Hill Fault (KHF) is one of the major E-W trending faults. An understanding of the episodes of reactivation during the past has a bearing on the future seismicity in the region. These reactivations are manifested by offset of elevation of fluvial sediments and scarp-derived colluvium in the Khari River basin, SE of Bharasar (23°11'36.5"N, 69°35'22.6"E). Stratigraphic offsets of the sediments at this site suggest three episodes of reactivation of the KHF during the late Quaternary. Optical dating of samples from sediment strata and top layer of scarp-derived colluvium using Natural Sensitivity Corrected - Single Aliquot Regenerative (NCF-SAR) protocol suggested that these events occurred during the past ~30 ka, with the most recent historic episode around 3.0 ka. Given that a part of the slip recorded in the form of sediments offset, was lost due to erosion after faulting, a lower bound to the time averaged slip rate of the segment of KHF, is inferred to be > 0.23 mm/a during the past 30 ka.

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Modern fluvial sediment provenance and pollutant tracing: a case study from the Dřevnice River Basin (eastern Moravia, Czech Republic)

sheet 25-32 Zlín. Czech Geol. Surv. , Prague (in Czech). Johnsson M.J. 1993: The system controlling the composition of clastic sediments. In: Johnsson M.J. & Basu A. (Eds.): Processes controlling the composition of clastic sediments. Geol. Soc. Amer., Spec. Pap. 284, 1-19. Johnsson M.J. & Meade R.H. 1990: Chemical weathering of fluvial sediments during alluvial storage: the Macuapanim island point bar, Solimoes river, Brazil. J. Sed. Petrology 60, 6, 827-842. Kašpárek M. (Ed.) 1997: Map

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Methodological Aspects on Luminescence Dating of Fluvial Sands from the Moselle Basin, Luxembourg

Methodological Aspects on Luminescence Dating of Fluvial Sands from the Moselle Basin, Luxembourg

Optically stimulated luminescence (OSL) dating of quartz and infrared-stimulated luminescence (IRSL) dating of feldspar were applied to fluvial sands from the lower terrace (M1) of the Moselle valley in Luxembourg (western Europe). The dating results indicated that the aggradation period for the sediments from below the M1 alluvial terrace can be correlated to the Weichselian upper Pleniglacial (MIS 2), which is in good agreement with the general chronostratigraphy of the Moselle terrace staircase. The ages were obtained from small aliquots of quartz and feldspars, using the single aliquot regenerative (SAR) protocol. The equivalent dose determination included a series of tests and the selection of the Minimum Age Model as the most appropriate statistical model. This made it possible to provide a reliable methodological background for further luminescence dating of fluvial sediments from the Moselle basin.

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