Luminescence Dating Facility
Luminescence dating is a technique used to date Quaternary sediments and for determining when ancient materials such as pottery, ceramics, bricks or tiles were last heated. The technique can be applied to material from about 100 to several hundred thousand years old.
The Luminescence Dating Facility at Victoria University is the only one of its kind in New Zealand and is led by Dr Uwe Rieser and Ningsheng Wang. It is primarily a research facility for the School and for collaborators in New Zealand.
The laboratory is set up in dark rooms with extremely subdued orange illumination.
One room serves as preparation laboratory, where all incoming samples are unpacked and chemically treated to purify the sample and extract the desired minerals in the right grain size.
The other room houses most of the modern electronic equipment, including:
- 2 Riso TL-DA-15 measurement instruments, which each contain a 48-position automated sample changer, a beta-radiation source and stimulation devices for Thermoluminescence and Optically Stimulated Luminescence (infrared, green and blue light)
- 1 Daybreak E801 beta-irradiator with automated 30-position sample changer
- 1 ELSEC alpha-irradiator with 6 irradiation positions
- 1 Broad energy Canberra HPGe-gammaspectrometer with ultralow-background shielding (6-in low activity Pb, graded Sn and Cu, j-style configuration), 50% nominal efficiency
- 1 portable Silena NaJ-g-spectrometer (1k-multichannel instrument)
Luminescence Dating Service
Our luminescence dating service is available for researchers in New Zealand and overseas.
Optically Stimulated Luminescence
We use optically stimulated luminescence (OSL) to date aeolian, fluvial, lacustrine and shallow water marine sediments, as well as most quartz or feldspar-bearing objects, which have seen sunlight or intense heat during deposition.
These sediments can be used to study ancient earthquakes, tsunamis, flooding and volcanic eruptions, as well as climate change, glaciation and tectonic uplift.
We are also involved in research projects requiring gammaspectrometry. Applications involve measurement of artificial radionuclides in sediments (such as 137Cs from atomic bomb tests or 241Am from the Chernobyl accident) or measurement of sedimentation rates using naturally occurring 210Pb.
Our equipment has a very high efficiency and ultra-low background so can be used to measure tiny amounts of radionuclides. We therefore welcome projects where low-level radioactivity is expected such as sediments from New Zealand and the Pacific Islands.
Please enquire about our capacity and pricing.
Pricing and Turnaround Time
Standard rate for routine work with priority processing: NZ$1400 + GST per sample.
This price includes all irradiation and luminescence measurements required to obtain the equivalent dose, and high resolution laboratory gamma-spectrometry for dose rate determination. Please ask us for a quote for your sample analysis.
We will also advise you about sampling and help with the interpretation of results.
Turnaround time is dependent on the workload of the lab, so please enquire about the status when submitting samples. Unfortunately routine sample analysis can take up to five months, but can be longer for unusual materials or if any unexpected problems arise during processing.
This rate applies to Victoria University students, collaborators and unfunded researchers. Our reduced rate covers only our direct costs including consumables.
Samples at this rate are low priority and will be analysed as time slots become available. They will potentially have a long turnaround time, so please contact us for a time estimate when submitting samples.
We strongly encourage you to make contact with us prior to sample collection to:
- discuss the details of different sedimentary environments before sampling
- to evaluate alternative sampling options like augering or block cutting
- enquire about borrowing suitable sampling equipment from us.
Only sediments that have been exposed to light or intense heat during deposition are datable by OSL, so please consider carefully if this applies to your material.
We recommend using steel cylinders to collect sediment samples as they are easy to use and transport and protect samples from ambient light. The steel cylinders used by our laboratory have a diameter of 60mm and are 100 mm in length, with a sharp edge on one side. They are mounted on a base unit that takes the blows when the cylinder is hammered into the sediment, while also preventing mixing of loose sediment within the cylinder. We are happy to lend the cylinders and the base unit for use within New Zealand.
1. Identify a suitable sediment outcrop – ideally a sandy/silty consistency
2. Cut back the surface of the outcrop by about 20 cm to expose fresh material
3. Hammer in a cylinder so it is fully filled and carefully dig it out. Cover both ends of the cylinder with aluminium foil and/or thick black plastic, and tape it so it is light proof and watertight.
4. Attach a readable, meaningful label.
5. Avoid sampling in inhomogenous surroundings (stay more than 25 cm away from inhomogenities like gravel beds or bedrock)
6. Provide sufficient sample material:
- For fine material (eg: loess or other predominantly silty material), one full standard cylinder (60x100) is adequate
- For coarser material (eg: sand) two full standard cylinders are needed
7. Ensure the sample material cannot move or mix inside the cylinder, by stuffing aluminium foil into both ends of the cylinder.
Do not submit a sample without prior consultation.
We reserve the right to reject samples if we consider them unsuitable for luminescence dating.
Whenever possible we prefer to sample your materials ourselves to avoid contamination. If this is not possible, please ask us for advice to ensure correct sampling. We do not accept responsibility if samples were taken incorrectly.
Our pricing only covers our costs and is not for profit. While we are involved in work with some commercial clients, we prefer to work as part of collaborative research projects.
Please contact us if you think we could contribute to your research project.