by Dirk Mittelstraß | Last update: Nov 16, 2022
Luminescence dating might be the best tool to determine the age of Pleistocene landscapes and archaeological artefacts. Over the last years, I have been researching on new data analysis methods for some specific luminescence dating applications. This blog shall give you access to the new solutions I developed.
You can book me to perform detailed data analyses of the measurement data gathered with your OSL/TL reader. If you are interested to outsource sample preparation and/or luminescence measurements, I recommend to use the services of the LUNA luminescence laboratory at the Helmholtz Institute Freiberg for Resource Technology (HZDR) in Germany. The LUNA lab is a re-launch of the long-term activities in luminescence dating research in Freiberg and lead by Dr. Margret Fuchs (m.fuchs@hzdr.de). The lab is specialized on spectroscopic investigations for mineral exploration and characterization but also well-equipped for geochronological investigations. One special capability of the LUNA lab is the high-quality mineral separation in sediments through froth flotation.
| Dating application | Data analysis software |
|---|---|
| CW-OSL component separation at quartz | Introduction & Tutorial |
| Examples for quartz CW-OSL component identification and separation | |
| Spatially resolved IR-RF at K-feldspars | Research article published in the scientific journal Geochronology. |
| Download and installation | |
| Example data and sequences | |
| SR-RF macro Handbook and GitHub page | |
A new scientific paper I co-authored is published: Wavelength calibration and spectral sensitivity correction of luminescence measurements for dosimetry applications: Method comparison tested on the IR-RF of K-feldspar written by Mariana Sontag-Gonzales who is part of Markus Fuchs’s work group in Giessen. Mariana did an excellent job in describing multiple approaches for wavelength and sensitivity calibration of for luminescence spectroscopy and comparing them. As case study, the paper includes also IR-RF peak analyses of two K-feldspar samples.
Until January 03 2023, the paper can be downloaded for free and without institution access by using this link.
Finally, my OSLdecomposition function library for R is released on CRAN. The package can now be installed using the RStudio package manager or by simply typing this into your R environment:
install.packages("OSLdecomposition")If you are not familiar with what it is all about or how to use the package, check out the Introduction & Tutorial page.
My biggest scientific child, the OSLdecomposition
package, is about to be released at CRAN soon. I already submitted the
package to CRAN in May this year. The review process revealed a few
minor issues and one big one: The necessary computing time to perform
the fitting of the global OSL curve with fit_OSLcurve()
exceeded the allowed limits for the code examples. Even with minimum
examples, I could not get the computing time below 10 seconds while only
5 seconds are allowed for CRAN releases. As it turned out, my approach
to calculate the residual sum of squares (RSS) did a lot of memory
allocations and these are highly inefficient in R. By
incorporating the RSS calculation directly into to
decompose_OSLcurve() and taking care to create only as many
vectors and data.frame columns as truly necessary, I could speed up the
curve fitting between 3 and 5 times.
The research article presenting the method of grain-wise IR-RF dating of K-feldspars developed by Sebastian Kreutzer and myself has passed the review process in Geochronology and is now officially available at doi.org/10.5194/gchron-3-299-2021.
If you would like to discuss the future of IR-RF dating with me or Sebastian, why not register for the vDEUQUA 2021 online conference? The vDEUQUA is about quaternary climate and environmental changes, the methods to investigate them and how quarternary processes shaped our todays world. The conference is virtual, free of charge and happens from 2021-09-30 to 2021-10-01. See you there!
The package OSLdecomposition got an update, see the
Changelog for details.
The function RLum.OSL_correction() includes now an
algorithm that checks if the records contain not stimulated periods at
beginning aor end of the measurement and removes them. This is for
example useful to enable component separation in single-grain
measurements.
I’m happy to anounce that our manuscript about spatially
resolved IR-RF dating is accepted for discussion in the journal
Geochronology. The preprint is available at gchron.copernicus.org.
Short comments are allowed until March 11.
Just in time for the DLED2020,
we released our R package OSLdecomposition for
signal component identification and separation in multi-exponentially
decaying measurements. Our focus laid on continous-wave optically
stimulated luminescence (CW-OSL) measurements of quartz samples for
dosimetry purposes. But you might find the package helpful for other
applications too. Check out our DLED
poster for a quick introduction into the Why and
How.
Welcome to my site about new data analysis methods for luminescence dating measurements. Since about 2013, I worked at number of methods on this issue. This blog is meant to give you access to some of my findings and the software I developed. As this blog will slowly get more content over the next months, I hope to see you around sometime!
© Dirk Mittelstraß, 2020 - 2022 | This website was created with Rmarkdown