Early Holocene forest fires, drift sands, and Usselo-type paleosols in the Laarder Wasmeren area near Hilversum, the Netherlands : Implications for the history of sand landscapes and the potential role of Mesolithic land use
Sevink, Jan ; Geel, Bas van; Jansen, Boris ; Wallinga, Jakob - \ 2018
Catena 165 (2018). - ISSN 0341-8162 - p. 286 - 298.
Drift sand - Early Holocene - Mesolithic - OSL - Paleosols
In the Laarder Wasmeren area in the western Netherlands, Late Pleistocene cover sands and overlying early Holocene drift sands show various paleosols, which can be characterized as more or less incipient podzols. We dated those soils and sands by radiocarbon analysis and OSL, and we used biostratigraphical dating based on the known chronology of the vegetation history. Apart from Usselo soils of Allerød age, we found early Holocene soils - showing Usselo soil characteristics but with relatively advanced podzolisation - covered by Early Holocene-early Middle Holocene drift sands. We discuss their age and origin, and reflect on the role of fires and ecosystem degradation in the early development of heathland, podzols and drift sands in the Netherlands, prior to any Neolithic farming. We hypothesize about the possible role of Mesolithic man, stimulating habitats for Corylus avellana by burning pine forest, in the longer term inducing the observed ecosystem degradation (transformation of forest into open short vegetation, acidification and concurrent podzolisation, wind erosion). This hypothesis is in line with studies in adjacent NW-European countries, which are reviewed, and an alternative for the theory of Vera (2000), who assumed that open forests and short vegetation resulted from grazing pressure by large herbivores.
Centennial- to millennial-scale hard rock erosion rates deduced from luminescence-depth profiles
Sohbati, Reza ; Liu, Jinfeng ; Jain, Mayank ; Murray, Andrew ; Egholm, David ; Paris, Richard ; Guralnik, Benny - \ 2018
Earth and Planetary Science Letters 493 (2018). - ISSN 0012-821X - p. 218 - 230.
erosion rate - exposure dating - luminescence - OSL - rock surface - weathering rate
The measurement of erosion and weathering rates in different geomorphic settings and over diverse temporal and spatial scales is fundamental to the quantification of rates and patterns of earth surface processes. A knowledge of the rates of these surface processes helps one to decipher their relative contribution to landscape evolution – information that is crucial to understanding the interaction between climate, tectonics and landscape. Consequently, a wide range of techniques has been developed to determine short- (<102 a) and long-term (>104 a) erosion rates. However, no method is available to quantify hard rock erosion rates at centennial to millennial timescales. Here we propose a novel technique, based on the solar bleaching of luminescence signals with depth into rock surfaces, to bridge this analytical gap. We apply our technique to glacial and landslide boulders in the Eastern Pamirs, China. The calculated erosion rates from the smooth varnished surfaces of 7 out of the 8 boulders sampled in this study vary between <0.038±0.002 and 1.72±0.04 mmka−1 (the eighth boulder gave an anomalously high erosion rate, possibly due to a recent chipping/cracking loss of surface). Given this preferential sampling of smooth surfaces, assumed to arise from grain-by-grain surface loss, we consider these rates as minimum estimates of rock surface denudation rates in the Eastern Pamirs, China.
Realizing the potential of fluvial archives using robust OSL chronologies
Cunningham, Alastair C. ; Wallinga, Jakob - \ 2012
Quaternary Geochronology 12 (2012). - ISSN 1871-1014 - p. 98 - 106.
Bayesian - Bleaching - Bootstrap - Chronology - Fluvial - Likelihood - Luminescence - OSL - OxCal
Optically Stimulated Luminescence (OSL) dating has enormous potential for interpreting fluvial sediments, because the mineral grains used for OSL dating are abundant in fluvial deposits. However, the limited light exposure of mineral grains during fluvial transport and deposition often leads to scatter and inaccuracy in OSL dating results. Here we present a statistical protocol which aims to overcome these difficulties. Rather than estimating a single burial age for a sample, we present ages as likelihood functions created by bootstrap re-sampling of the equivalent-dose data. The bootstrap likelihoods incorporate uncertainty from age-model parameters and plausible variation in the input data. This approach has the considerable advantage that it permits Bayesian methods to be used to interpret sequences containing multiple samples, including partially bleached OSL data. We apply the statistical protocol to both single-grain and small-aliquot OSL data from samples of recent fluvial sediment. The combination of bootstrap likelihoods and Bayesian processing may greatly improve OSL chronologies for fluvial sediment, and allow OSL ages from partially bleached samples to be combined with other age information.
Validating post IR-IRSL dating on K-feldspars through comparison with quartz OSL ages
Kars, R.H. ; Busschers, F.S. ; Wallinga, J. - \ 2012
Quaternary Geochronology 12 (2012). - ISSN 1871-1014 - p. 74 - 86.
Feldspar - Luminescence dating - OSL - Post IR-IRSL - Quaternary - Sediments
Recent developments have opened up the possibilities of using potassium feldspar for dating Pleistocene sediments; a stable (less-fading) part of the infrared stimulated luminescence (IRSL) signal can be selected by largely depleting the unstable part of the IR signal, using a combination of thermal and IR stimulation: post IR-IRSL dating (pIR-IRSL).This study aims to test the validity of pIR-IRSL dating on feldspars. We obtained pIR-IRSL ages on a large suite of samples from several locations in the Netherlands area, covering a wide range of depositional environments and ages. Age control was provided by quartz optically stimulated luminescence (OSL) ages on the same samples; these ages were shown to accord with geological age constraints. Comparison with IRSL ages enabled us to evaluate the improvement that pIR-IRSL dating provides over conventional IRSL methods.The majority of feldspar ages obtained with pIR-IRSL showed good agreement with both the quartz OSL ages and the geological age constraints. Our study demonstrates that pIR-IRSL dating is more robust than conventional IRSL and should be the method of choice in feldspar luminescence dating of Pleistocene sediments.
Expectations of scatter in equivalent-dose distributions when using multi-grain aliquots for osl dating
Cunningham, Alastair C. ; Wallinga, Jakob ; Minderhoud, Philip S.J. - \ 2011
Geochronometria 38 (2011)4. - ISSN 1733-8387 - p. 424 - 431.
Ali-quot size - Luminescence dating - MAM - Minimum-age model - OSL - Overdispersion - Partial bleaching
In the OSL dating of sediment, the scatter in equivalent dose (D e) between grains is almost always larger than would be expected due to counting statistics alone. Some scatter may be caused by insufficient (partial) bleaching of some of the grains prior to deposition. In order to date partially bleached sediment, it is essential to estimate the amount of scatter caused by other processes (e.g. grain-to-grain variability in the natural dose rate). Measurements of such scatter are performed at the single-grain level; by contrast, most OSL dating is performed on multi-grain subsamples, for which grain-to-grain scatter is reduced through averaging. Here we provide a model for estimating the expected scatter (i.e. excluding that caused by partial bleaching) for multi-grain aliquots. The model requires as input the single-grain sensitivity distribu-tion, the number of grains in the sub-samples, and the expected scatter at the single-grain level, all of which can be estimated to an adequate degree. The model compares well with measured values of scatter in De, determined using aliquots of various sizes, and can be used to help produce a minimum-age De from multi-grain subsamples that is consistent with single-grain data.
Non-resonant X-ray/laser interaction spectroscopy as a method for assessing charge competition, trapping and luminescence efficiency in wide band-gap materials
Poolton, N.R.J. ; Bos, A.J.J. ; Wallinga, J. ; Haas, J.T.M. De; Dorenbos, P. ; Vries, L. De; Kars, R.H. ; Jones, G.O. ; Drozdowski, W. - \ 2010
Journal of Luminescence 130 (2010)8. - ISSN 0022-2313 - p. 1404 - 1414.
OSL - Radioluminescence - TL - Trapping
Using a conventional fast-shuttered laboratory X-ray source in combination with pulsed laser diode modules, the possibilities for undertaking X-ray/laser interaction spectroscopy in wide band-gap luminescent materials are explored. It is shown that in such materials, a variety of X-ray/laser timing sequences can extract complimentary information regarding the charge-carrier trapping, de-trapping and recombination processes. The effects on the luminescence are illustrated for six example materials (YPO4:Ce,Sm, Lu 3Al5O12:Pr, Al2O3:C, natural sodium feldspar NaAlSi3O8, cubic BN and type IIa natural diamond). By ramping the temperature from 10 to 320 K during repeated X-ray pump/laser-probe activation cycles, a rapid assessment can be made of the important thermally dependent changes to the charge carrier trapping competition processes.
Selection of integration time intervals for quartz OSL decay curves
Cunningham, Alastair C. ; Wallinga, Jakob - \ 2010
Quaternary Geochronology 5 (2010)6. - ISSN 1871-1014 - p. 657 - 666.
Channels - Early background - Integration time intervals - Luminescence dating - OSL - Partial bleaching - Quartz
In quartz optically stimulated luminescence (OSL) dating protocols, an initial integral of the OSL decay curve is used in the calculation of equivalent dose, once a background integral has been subtracted. Because the OSL signal commonly contains a number of exponentially decaying components, the exact choice of time intervals used for the initial-signal and background integrals determines the composition of the net signal. Here we investigate which combination of time intervals will produce the net signal most dominated by the fast OSL component, while keeping an acceptable level of precision. Using a three-component model of OSL decay, we show that for a specified level of precision, the net signal most dominated by the fast component can be obtained when the background integral immediately follows the initial signal and is approximately 2.5 times its length. With this 'early-background' approach, the contribution of slow components to the net signal is virtually zero. We apply our methods to four samples from relatively young deposits. Compared to the widely used 'late-background' approach, in which the background integral is taken from the last few seconds of OSL, we find less thermal transfer, less recuperation and a higher proportion of aliquots yielding an equivalent dose in agreement with expectations. We find the use of an early background to be a simple and effective way of improving the accuracy of OSL dating, and suggest is should be used in standard protocols.
A modified SAR protocol for optical dating of individual grains from young quartz samples
Ballarini, M. ; Wallinga, J. ; Wintle, A.G. ; Bos, A.J.J. - \ 2007
Radiation Measurements 42 (2007)3. - ISSN 1350-4487 - p. 360 - 369.
OSL - Quartz - SAR - Single grain - Young deposits
We investigate the feasibility of a modified single-aliquot regenerative-dose (SAR) protocol for OSL dating of individual grains from young samples (< 300 years) using dose-recovery tests. Parameters such as pre-heat temperature, test- and regenerative-dose size, an additional bleaching step at high-temperature and optical stimulation time are optimised to give the highest percentage of accepted grains. The optimised protocol makes use of a 50 Gy test dose, a single regeneration dose of 5 Gy, an additional bleaching step and an optical stimulation of 10 s. This protocol is applied to two coastal-dune samples. Equivalent doses close to those obtained for multiple-grain single-aliquot measurements can be retrieved if: (1) short integration intervals (0.034 s) are used for the natural and regenerated OSL signals as well as the test-dose responses and (2) the background is estimated from the subsequent 0.034 s, and the net signals are used to determine the equivalent dose. Standard background subtraction methods lead to overestimation of the equivalent dose for these samples due to incorporation of a slow OSL component that was not completely reset at the time of burial.
Luminescence dating of Netherland's sediments
Wallinga, J. ; Davids, F. ; Dijkmans, J.W.A. - \ 2007
Netherlands journal of geosciences 86 (2007)3. - ISSN 0016-7746 - p. 179 - 196.
Feldspar - Luminescence dating - OSL - Quartz - Quaternary
Over the last decades luminescence dating techniques have been developed that allow earth scientists to determine the time of deposition of sediments. In this contribution we revity: 1) the development of the methodology, 2) tests of the reliability of luminescence dating on Netherlands' sediments; and 3) geological applications of the method in the Netherlands. Our review shows that optically stimulated luminescence dating of quartz grains using the single aliquot regenerative dose method yields results in agreement with independent age control for deposits ranging in age from a few years up to 125 ka. Optical dating of quartz has successfully been applied to sediments from a wide range of depositional environments such as coastal dunes, cover sands, fluvial channel deposits, colluvial deposits and fimic soils. These results demonstrate that optical dating is a powerful tool to explore the natural archive of the Netherlands' subsurface.