TL and OSL

7/28/2019 TL and OSL

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Thank you for your interest in using the U.S. Geological Survey TL / OSL lab forsediment dating. In this information "booklet" there are several sections thatyou will find useful. Section I covers general TL and OSL methodology andassumptions, Section II covers dose rate (D R) calculations and how the elementsare measured quantitatively, while Section III guides the reader through labpreparation of a sample and subsequent measurement of equivalent dose (D E).

Section IV reviews sampling in the field for TL and OSL and other material thatmay be dated using luminescence. Section V introduces quick and general factsabout the technique range, explanations for differences in TL and OSL techniques,reasons why different luminescent techniques are applied to differentdepositional sample types and other labs to contact in the U.S. Some labs, otherthan the USGS lab, may be more helpful for archeological applications, mayrespond with a cheaper price or offer faster response time depending on the

need for a particular analysis.

Section I: General TL and OSL Methodology(and Assumptions)

If a sample of sediment is heated rapidly to 500C, there is weak butmeasurable emission of light. This light is known as thermoluminescence(TL) and is based on time-dependent accumulation of radiation damage inminerals. Optically Stimulated Luminescence (OSL) is measured byshining a beam of light onto mineral grains and measuring the resultingluminescence back. A low level of ionizing radiation, which we measurefrom 40 K , 238 U, 235 U, 232 Th and daughter products, 87 Rb and cosmic rays isomnipresent in nature. Almost exclusively, luminescence from quartz andfeldspar grains is used in dating.

The interaction between this radiation and the atoms of minerals resultsin gradually increasing radiation damage. The intensity of the radiation

damage in crystal lattices is a measure of the Equivalent Dose (D E) ,which the mineral has received since formation or last "resetting" byexposure to sunlight or heat over 300C. The mineral is used as a naturaldosimeter. D E is measured in Gray (Gy) or absorbed radiation energy perunit mass. Once one has "read" the D E by means of a TL or OSL measurement, the Dose Rate (D R ) is obtained viameasurement of K , U, Th,Rb and cosmic rays as dose per unit timeor Gy/Ka. The equation for obtaining an age is:

Age (Ka) = D E (Gy)/D R (Gy/Ka)
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To evoke the emission of TL and OSL, additional thermal or opticalstimulation, respectively, has to be supplied to the crystal. Luminescenceis created by the ionizing radiation freeing electrons that wander throughthe crystal lattice until they encounter a trapped hole or recombine andbecome trapped at electron traps that are lattice defects with negativecharge deficits. During luminescence measurement, "traps" are emptiedand luminescence centers destroyed. The longer the crystal has beenexposed to ionizing radiation, the more "traps" can be filled, resulting inan increased luminescence signal, with a practical time limit of 800 Ka (Berger, G.W., 1994, Thermoluminescence Dating of SedimentsOlder than 100 Ka, Quaternary Geochronology, Quaternary ScienceReviews , 13, 445-456).

Key assumptions are:

1. Materials have uniform anddefinable dose rates.

2. Moisture content of the sample andits environment can be determined.

3. Depth, altitude and intensity of

cosmic rays on site can becalculated or are known.

4. The radiation-induced signal has tobe thermally or optically reset bythe event to be dated. The rate andcompleteness of "resetting" can bereliably obtained.

5. The TL or OSL must have been

stable during the time span inquestion. Any spurious "fading"of TL or OSL can be measured andcompensated for in age calculations.

6. The TL and OSL growthcharacteristics have to follow amathematical function.

The principal minerals used in OSL are quartz and K feldspar, although

use of volcanic glass and some forms of calcite and zircon have beenused. The principle minerals used in TL are polymineralic or separation of


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the quartz or feldspar. M.J. Aitken ( Thermoluminescence Dating , 1985,Academic Press, 359 pages and An Introduction to Optical Dating , 1998,Oxford University Press, 267 pages) presents a very able discussion of thecomplete TL and OSL techniques.

Section II: Dose Rates and How They AreObtained

The rate at which trapped electrons are accumulated is proportional to theenergy absorbed during burial. Several components are needed for anaccurate D R; 1). measurement of K , U, Th and Rb 2). calculation of moisture content in field at time of collection and saturation potential of

the sample sediment and 3). cosmic ray component calculation.

DR's are taken from the combination of material around each site to bedated. These include neutron activation (INAA), atomic absorption,X-ray fluorescence (XRF), flame photometry (K only) andinductively coupled plasma mass spectrometry (ICP-MS) . Thefundamental disadvantage of these methods is they do not accountfor U and Th being in disequilibrium.

Equilibrium can be checked by using alpha spectrometry or high-resolution gamma spectrometry , since these methods measure theactivities of several individual radionuclides in the decay chains. Usuallythe facilities required for these techniques are expensive andmeasurement time can be long.

Another routine approach that minimizes possible error due todisequilibrium is thick source alpha counting (TSAC) which determines

the Th and U and the K as above. TSAC can also be used to count only foralpha contribution and the beta contribution can be determined bya beta TLD or particle counter (high sensitivity TL dosimetryphosphor) .

The method in use at the USGS lab is gamma ray spectrometry, due to aninherited collection of NaI crystals from radioactive chemistry labs. High-resolution gamma-spectrometry is carried out on a 600-gram sample (theideal weight since less material means higher counting errors); admittedlya lot of sample, but the crystals date from the early 1980's. However, this


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amount of sample more adequately represents the variations and mixthat the collected sample might have absorbed during deposition, ratherthan relying on the one or two gram quantity normally counted in othertechniques. Apart from elemental quantification, this technique enablesthe checking of radioactive equilibrium (see assumption #1). The samplesare measured on four (4) different crystals for ten (10) hours per crystal.

Moisture and radon migrations are not factors because the bulk samplehas been dried and sealed for a month and radon allowed to equilibratebefore counting. We collect gamma spectra and then fitted to standardspectra of K , U, and Th using the least square criterion. Elementsmeasured in standard materials provide quality assurance as they run

alongside the unknown samples. Comparisons betweenthe USGS luminescence laboratory and published NBS(now NIST)and USGS Open-Files literature values for these standards show excellentagreement. Most of the scatter can be attributed to counting statistics.

Occasionally, the lab will compare the K concentration of samples using X-ray fluorescence (XRF). General agreement, within 1 sigma, providesanother check on secular equilibrium. If the lab suspects the sample to behigh in Rb, this element will be analyzed on the XRF as well.

It is most desirable to measure the gamma dose-rate on-site. This is sothat if there is any doubt about uniformity of radioactivity within the 30-cm sphere of influence of the surrounding sample, the readings will showsuch variations, even if a laboratory high-resolution gamma spectrometeris available to count after collection. The USGS lab keeps aportable NaI crystal for this purpose and will loan it out if the USGS scientist is unable to collect the samples. The sample site

should be counted for an hour or more, to provide high resolution andaccount for present field moisture or large stones. The lab crystals areunable to reproduce moisture conditions or stone placement, since thesample is usually dried and sieved before measurement.

The annual D R to the sample is computed from the concentrationsof K , U and Th by the method described in several literature sources,Aitken, 1985 (Thermoluminescence Dating, M.J. Aitken, 1985, AcademicPress, London, pp. 10-12 and pp. 282-288). The lab initially assumessecular equilibrium in the U decay series, unless comparisons in randomly


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picked samples show otherwise. The measurements must now includealpha, beta, and cosmic radiation and factor in the reduced effect of alpharadiation relative to gamma and beta radiation. Annual radiation dosesin Gy/Kataken from Aitken, 1985 are adapted as shown in Table 1.

Table 1

Alpha Beta Gamma

1% Rb -------- 4.00 --------

1% K -------- 0.83 0.24

1ppm U

2.78 0.15 0.11

1ppm Th

0.74 0.03 0.05

A reasonable estimate is made of the moisture content through geologictime with the understanding that this estimate carries a large uncertainty.Ages are calculated using field moisture percentage, unless unusualconditions prevailed at the time of sample collection, i.e. sustained rainover a period of time, drought or human disturbance. Water attenuationcorrections for each type of radiation are made using moisture correction

factors taken from Aitken, 1985. The actual equations used can be foundin USGS Open-File Report 94-249 pp.18-21.

In comparison with silicates, water has a significantly higher massabsorption coefficient for alpha, beta and gamma rays, but negligibleradioactivity; hence it more or less attenuates the D R and can significantlychange the radiation a sample may have absorbed. Therefore, the labalso calculates ages based on the sample being fully saturated. In thefinal report there will be listed a "halfway" value; that is the samplemoisture content may have had dry and wet frequencies during depositionof unknown duration, but somewhere between conditions at time of collection and a fully saturated value. There will be three ages listed foreach sample for each technique, each age corresponding to a differentwater moisture value. It is the client's prerogative to quote which agebest fits their carefully researched scenario.

The lab then calculates the dose rates for element/radiation combination

using the annual radiation doses in Table 1, the corrections forattenuation of water, and the alpha k-effective value (0.10 0.03).


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(Equations can be seen inUSGS Open-File Report 94-249 pp. 18). Thedose rate for the various element/radiation combination are combined togive the dose rates for the radioelements as follows:

Rb, K , U, and Th for the three types of radiation."> Table 2

Alpha Beta Gamma

Total D R Rb -------- D R Rb --------

Total D R K -------- D R K DR K

Total D R U DR U D R U D R U

Total D R Th DR Th D R Th D R Th

The final component of cosmic ray value is added now to the dose ratecalculations. The value, 0.291 Gy/Ka, is the cosmic ray dose at sea leveland latitude 38 South and is taken from Prescott and Hutton, 1988. Thisvalue is valid for latitude greater than 40, but must be corrected for thesample elevation above sea level and depth within the sediment. Aitken,1985 p. 298 present a graph of the elevation factor versus elevation fordifferent latitudes. The low elevation portion of the curve (about 3,000meters or 9,000 feet.) is approximately linear with slopes shown in Table

3.

Table 3

Latitude Slope

>40 8.2-5/foot

25 6.1-5/foot

0 4.0-5/foot

Values for the depth factor are taken from Prescott and Hutton, 1988 andmay be read from USGS Open-File Report 94-249, p. 19. Finally, thetotal D R of the sample is computed using D R of cosmicray, D R of Rb, D R of U, D R of Th andD R of K .

Errors are calculated in a separate program to 2 sigma, using standardformulas from Taylor, 1982 (An Introduction to Error Analyses, UniversityScience Books, 1982, pp. 148-150).


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Section III: Lab Prep and Equivalent Dose(D E) Analyses

A full explanation of USGS lab procedure may be read in USGS Open FileReport 94-249. The USGS lab uses three grain sizes: a polymineralic 4-11 fine silt for both TL and OSL dating, 90-125 quartz for OSL (BlueLight-Optically Stimulated Luminescence) and 180-125 or 90-125 (depending on quantity and difficulty in calculating D R) K-feldsparfor IRSL-OSL (Infrared Stimulated Luminescence). Before sieving fordesired size fractions, each sample is treated with 4N HCl to removecarbonate, 30-35% H 2O2 to destroy organic material and is dispersedin Napyrophosphate solution. Wet sieving and Stoke's settling in de-ionized water are employed to achieve desired size fractions. Heavy liquidseparation is used on the larger grains to separate quartz from feldsparby using lithium polytungstate (LST). Short sample etches in Hydrofluoricacid (HF) for the quartz fraction are be used to clean surfaces andimpurities. HF of 45-50% is used for 40 minutes, followed by a 5-minutebath of 4N HCl. These samples are then run as loose grains on cups.

The silt size portion of the sample (4-11 ) are then plated on 1 cm size

aluminum disks from a grain suspension in methanol, while the largerfraction (90 and larger) are poured loosely into cups. All procedures areperformed under reduced lighting conditions to minimize artificialbleaching of the samples. The intensity of the sodium vapor lights in thelaboratory,which emit a single wavelength (589 nm), are adjusted toprovide enough requisite sensitivity for the human eye but not bleach thesamples.

The silt size sample disks are normalized for sample homogeneity by a 5-second exposure to infrared illumination and detection of the resultingluminescence by a photomultiplier tube covered with Schott BG-39 andKopp 7-59 filters, as well as a Pyrex window. The TL signal is reduced byabout 2% by this treatment and the IRSL signal by about 1%. The largersize fraction are measured using a single aliquot technique and thusrequire no normalization.

Samples are measured for TL and OSL separately, which requires the use

of many disks or cups. TL is obtained by heating the disk to 500C andthe electronically intensified light emission is recorded as a function of the


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heating temperature. After each measurement the heating is repeated torecord and subtract background. Most of the signal is due to TL fromquartz and feldspars. The TL instrument records the signal asphotons/5C intervals and plots the resulting glowcurve as TL signalversus temperature. The glows are actually a composite of TL peaks fromdifferent traps. It is crucial to conduct TL measurements under the purestnitrogen (or argon) atmosphere to prevent unwanted chemiluminescence,which is energetically fed from exothermic chemical reactions.

Silt size, polymineralic IRSL is obtained by exposing the disk to a30mA current to infrared LED's, 1 second dwell time per channel for 100channels, 100 second total time exposure, sample temperature held to

30C and a background count taken before and after a set of samples isexposed under the photomultiplier tube. (It is not necessary toobtain IRSL under nitrogen atmosphere). The coarser grains measured onthe Riso System are done so under a steady light from either blue orinfrared diodes. The blue light emission is given in the 400-550nm range(centered at 470 30) and infrared emission is from the 800-900 nm range (centered on 880 20 >nm).

Optical filters are inserted between the sample and photomultiplier tubeto permit the recording of specific spectral regions. For optical filtersthe USGS lab uses Schott BG-39 (at the upper level) and Kopp 7-59 (atthe lower level) for both TL and IRSL, on the Daybreak system analyses.On the Riso system analyses a U-340 detection window helps cut off spillover from blue light emission at the 350-400 nm range and BG-39 filters out 300-700 nm (helps to gain sensitivity). For Risomeasurement of feldspars >U-340 and RG-715 are the common filters.

The fine-grain technique requires the determination of the a-value andthus the use of an alpha source as well as a beta source. These sourcesare used to artificially irradiate sets of disks so that a curve will resultfrom increased TLgrowth induced by the laboratory "aging". This curve isthen extrapolated back to its intersection with a residual baseline. Thebaseline is defined by the TL or IRSL signal from a natural disk. The disksare exposed to 8 to 16 hours of natural sunlight for TL or 5 to 10 minutesfor OSL. The alpha source in use at the USGS lab is 241 Am at 0.5-

mCistrength and two beta sources of 90

Sr at 100 mCi and200 mCi respectively.


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There are many methods a lab can use to generate D E. The methods inuse by the USGS lab are the "total bleach" with a preheat of 124C (62hours) and a "total bleach" with a preheat of 140C (6 hours) for TL."Additive dose" of 124C (62 hours) and "additive" dose of 140C (6hours) for IRSL, and single aliquot analysis for both bluelight OSLand IRSL large grains at 220C (5 minutes), fading tests at allpreheats and a sunlight sensitivity test. Not all experiments areperformed for every sample.

The traps of some minerals, particularly feldspars are afflicted by themalign phenomenon of anomalous fading. Such fading is anomalous inthat observed stability is much less than predicted from kinetic

considerations. The test for anomalous fading establishes theeffectiveness of the preheat treatment for removing the lessstable TL and OSLcomponents generated by beta or alpha irradiation.

In the "total bleach" method, irradiating sets of natural disks for variouslengths of time generates a growth curve. The longest of these times ischosen to produce about 8 times the best estimate of the D E for aparticular sample. The resulting TL signals are plotted against theradiation dose. The intersection of this curve with a residualdefinesD E. IRSL "additive dose" technique is also approached in the samemanner. Glowcurves illustrating this process are included in a samplereport.

In order to test if the signal of natural TL has been stable over the agerange in interest, the plateau test is applied. In the plateau test the D E orthe TL age is calculated in dependence of the glow curve temperature.The start of the plateau value is indicative of the thermal stability of the

analyzed TL signal. The plateau can be thermally "washed" throughpreheating to obtain better development of plateaus. This is why theclient might note differently defined plateaus for samples at differentpreheat temperatures. The USGS lab uses two distinct preheats in aneffort to fully test plateau placement. Experience and judgement can playa large role in choosing the D E for each sample. OSL D Edoes not have aplateau property; thus a TL run on the sample is usually done simply to

judge the potential stability of luminescence within the sample, even if it

is believed that the TL has been incompletely reset due to attenuatedlight exposure.


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The TL and silt-size IRSL data are run and reduced using the Daybreak1100SI TL Application software (registered trade name). This softwarecomputes a growth curve for the data points generated by passing avertical line (single temperature) through the family of glowcurves. Aleast squares fit is made either to a line passing through the points or, forthe saturating exponential, a line passing through a logarithmictransformation of the data. An iterative algorithm is employed for thelatter fit. The natural (unirradiated) disks are given double weight. TheDaybreak software estimates errors for D E using Rendell's equation #1 forthe regression of TL signal on dose (Rendell, 1985).

OSL data is collected from the quartz grains of 90-125 size or

occasionally the 125-150 size grains. These grains have been putthrough a further refined process using heavy liquids (LST) to separatethem from the heavy minerals and feldspars. The quartz furtherundergoes a Hydrofluoric acid etch for 40 minutes (etching away thealpha radiated layer). Samples are run and reduced using a Riso TL/OSL-DA-15A/B (registered trade name) system. Riso system software wasspecially developed for the determination of the archeological andgeological ages from quartz and feldspar in collaboration with Dr. Rainer

Grun (Australian National University, Canberra, Australia). The specialapplication software for the single aliquot regeneration (SAR) analyseswere developed by G.A.T. Duller (University College of Wales,Aberystwth, UK) and Dr. Andrew Murray (Nordic Laboratory of Luminescence Dating at Riso, Roskilde, Denmark). Complete analysis andprocedures followed in the USGS lab are taken from a 2000 paper of Andrew Murray and Ann Wintle (Luminescence Dating of Quartz Using anImproved Single-aliquot Regenerative-dose protocol, RadiationMeasurements, 32 (2000), pp. 57-73).

Various combinations of these parameters furnish many variants of the TL and OSL technique of dating. In consequence the dating of aparticular sample by several laboratories will not necessarily yield directlycomparable ages---although we feel they should at least have overlappingage ranges. It is important to present this experimental proceduretogether with the age data. The results of the measurements can't be

judged without this important information. Only then can ages be

evaluated with a realistic quoted error.


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The use of firm, trade, and brand names is for identification purposes only and does not constitute endorsement by the U.S. government.

Section IV: How to Collect Samplesfor TL and OSL Dating

In general, try to avoid sediments that show any post-depositionaldisturbances such as root penetration, krotavinia (bioturbation),carbonates, ground-water leaching, certain soil formations or large stonesthat may hamper sampling. If the only exposure that is available is one inwhich cracks, roots or krotovina may be encountered at depth, or thesediment is so hard that it will be difficult to remove a tube driven in at

depth, then take a cube block sample at the site. Mark the sample as tothe side exposed to the surface. Wrap it in aluminum foil, a black bag(several layers if being shipped) and tape tightly to preventdisintegration.

Ideally, a 0.5 meter (about a one-foot hole) must be augured into the soilsample above or below the boundary of the layer so that theluminescence and bulk samples are taken or counted on a homogenouslayer. If this is not possible, take the luminescence sample and digsideways for adequate bulk sample sediment. Sampling tubes of either0.15" wall PVC (white or black) or steel should be driven into the back of the hole to collect the luminescence sample. PVC tubes often benefit froma sharpened or beveled edge on the back of the tube to be driven into thesediment. Tubes are driven in by sledgehammer, however, a hard metalplate should be used against the end being hammered to preventshattered or collapse.

If the sample is being collected during the daylight hours, a black oropaque cloth MUST be used to shield the sample collection and theimmediate site from light upon removal of the sample. If the sample iscollected at dusk or night, a red-filter light can be employed at aminimum for collector's visual aid. The lab will need about 50 grams of sediment if the sample is fine-grained, about 75 to 100 grams if thesample is sand-size for adequate replicate analyses.

The sample tube should then be carefully pried or dug out from the holeby pushing a knife or chisel alongside the tube and levering it sideways.


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Cover the sample hole with a black cloth (this may require the aid of others) while freeing the tube. Once the tube is free, DO NOT remove itfrom the hole or black cloth until the open end is closed with a black capor duct tape. Both ends of the tube can then be sealed with blackelectrical tape if the caps look loose or if they might pop off during sampleshipment. Place the tubes in a black polyethylene black bag (the kindused in photography supply stores and not black trash bags). Write thesample name on both tube and bag.

A second sample must be collected from the back or sides of the samehole. This sample, referred to as the "bulk sample", does not needprotection from light. The bulk sample should be collected in a double

Ziploc 1 quart size bag to inhibit the loss of moisture, so that grossmoisture content can be measured in the lab. This sample can also beused to obtain a D R if field analysis is not possible. In that case, at least600-grams of sample is needed for the gamma ray counting.

Photographs or trench logs showing the locations of samples should beincluded if possible. Usually one photograph is required to locate thesample hole in stratigraphic context and one close-up to show texture of the sediment sample. The augured holes often show up well in distantphotos of the site. Location of the site using GPS systems is appreciatedand depth of sample below the original surface of the ground should benoted, as these are needed for a calculation of cosmic ray component of the D R.

Other materials that can be collected to datearcheological finds using luminescence:

1. Artificial Glass: There have been few successful attempts, causedprincipally by glass' non-crystalline state.TL and OSL can only used if glass has not been heated above "glass transition" temperature (? C).(Mueller, P. and Schvoerer, M., 1993, Archaeometry 35: pp. 299-304,Factors Affecting the Viability of TL Dating of Glass).

2. Burned Flint and Stones: Well suited for TL, especially in dating Middleto Lower Paleolithic periods. Zeroing requires 450C and this assumptioncan be tested for. Oldest age obtained is 453 39 Ka. (Richter, D.G.,1997, Dissertation for University Tubingen, in German, no translation).

Potboilers (heated stones) have also been successfully dated. (Huxtable,J., Aitken, M. J., Hedges, J. W., Renfrew, A. C., 1976, Archaeometry


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18: pp. 5-17, Dating a Settlement Pattern by TL: The Burnt Mounds of theOrkneys).

3. Ceramics and Burnt Clayware: Important concepts of TL methods wereestablished on ceramic shards, bricks and kilns during the 1960's and

1970's. The usual method is to date both polymineralic fine-grains (4 to11 ) and quartz coarse-grains (100-200 ), thus combining TL ages.Typical error is 6-10%. (Wagner, G.A. and Lorenz, I. B., 1997, anotheruntranslated German paper).

Medieval kiln structures or the burned surface lining (containing quartz)have been successfully dated (Wagner, G. and Wagner, I., 1994, anotheruntranslated German paper).

Authenticity dating of ceramic objects uses both TL and OSL. For TL, thelab needs 200 mg of powder and only really looks for baseline signal,

indicating recent age or a natural TL glowcurve, indicating some elapsedtime greater than 500 years. (Aitken, M. J., 1985, ThermoluminescenceDating, Academic Press, 359 p.). For OSL, 100 mg or less is needed andhigher precision of measurement gives 1-2% error if the single-aliquotmethod is used. (Mejdahl, V. and Botter-Jensen, L., 1997, RadiationMeasurements 27: pp. 291-294, Experience with theSARA OSL Method).

Success in using the quartz extracted from fired bricks has been obtained,recently in using Chernobyl exposed bricks to the increased radiationduring the accident as "dosimeters" for reconstruction of dose rates(Banerjee, D., Botter-Jensen, L. and Murray, A.S., 2000, Applied Radiation

and Isotopes 52: pp. 831-844, Retrospective Dosimetry: Estimation of theDose to Quartz Using the Single-aliquot Regenerative-dose Protocol).

4. Slags: Attempts have been made to date archeometallurgic slag by TL,but the glass phase is problematic. Since slags consist essentially of silicates, heated to high degrees, in theory even OSL should work.Uncertainties about D R, however, render errors at 20%. (Elitzsch, C.,Pernicka, E., and Wagner, G. A., 1983,PACT 9: p. 271- 286, TL Dating of Archeometallurgical Slags).

5. Vitrified Forts or Earth Mounds: Prehistoric walls consisting of vitrified

quartz and feldspar bearing rocks are of widespread occurrence in westernEurope and TL ages have been obtained from Scotland. (Sanderson, D. C.W., Placido, F. and Tate, J. O., 1988, Nuclear Tracks and RadiationMeasurements 14: pp. 307-316, Scottish Vitrified Forts: TL Results for SixStudy Sites).

In northeastern Louisiana Paleo-Indian earthworks have been dated,presuming exposure to sunlight during construction or occupation of themound. Dating was by means of OSL using 90-120 quartz. Insufficientbleaching proved to be a problem, even with OSL, but minimum ageswere obtained (Feathers, J. K., 1997, Quaternary Geochronology 16: pp.

333-340, Luminescence Dating of Early Mounds in Northeast Louisiana).


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6. Wasp Nests: Using OSL to date quartz grains imbedded in petrified mud-wasps nests is a new way to give dates to rock petroglyphs and paintings.Nest thickness need to be at least 5mm and in some cases, anexperimental method of single-aliquot analyses (due to lack of material)gave excellent results. Ages up to 16.4Ka were obtained with about 10%

error. (Roberts, R., et. al., 1997, Nature: vol. 387, pp. 696-699,Luminescence Dating of Rock Art and Past Environments using Mud-waspsNests in Northern Australia).

Section V: Explanation for Differencesin TL and OSL Techniques and Other ClosingComments

Advantages of TL over OSL:

1. Stability of luminescence can be judged by "plateau test"

2. Less sample preparation and analysis time required

3. Wider age range published in literature

4. More reliable older ages past 200 Ka (published or otherwise)

Advantages of OSL over TL:

1. Deals with easily bleached component, requires less "resetting" time (5minutes versus 8 hours)

2. No brute heating of sample needed, can be measured easily

3. Single grain or aliquot analyses readily available (great for fluvial, glacialand lacustrine sediments)

4. Thoroughly bleached grains can be picked out for analysis

General outside agency pricing: $1200/sample (US$)

USGS in-house pricing: one pay period of time ($4,700) allows for sixsamples to be processed

Services offered: TL on 4-11 micron () silts, IR-OSL (infraredstimulated luminescence) on 4-11 polymineralic or feldspar grains or90-125 feldspar grains and BLUE-OSL (blue light optically stimulated

luminescence) on 90-125 quartz grains


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Methods offered:

Additive, multi-aliquot; partial bleach; multi-aliquot for TL Additive, multi-aliquot; single aliquot for IRSL Single aliquot regeneration for Blue light-OSL Anomalous fading tests (every sample) and sunlight sensitivity tests (one

sample per site)

Dose Rate: Field measurement by gamma spectrometry (K , U, Th andcosmic ray) or lab gamma spectrometry withNAI crystals (K , U and Th).Optional measurements of K by XRF; of U, Th with ICP-MS;or K , U and Th by INAA.

Sample turnaround time: Six (6) samples take three months to date

(from time of sample receipt in lab). No ages are released until we aresatisfied about the quality of the data. Sample turnaround times may beslower, but never faster. Remember that these samples haveaccumulated for thousands of years; it takes a few months to reveal theirsecrets.

Range of TL: 1,000-800,000 years with the 800,000 years heavilydependent on Dose Rate. Most samples have a practical application of

1,000 to 500,000 years.

Range of OSL: 10 - 175,000 years.

USGS lab: In operation since 1992. Latest equipment from Riso Labsoffering Blue-light OSL capability. Specializes in all geological applications,with published results mostly in the western U.S..

Contact: SHANNON MAHAN, Box 25046, MS 974, Denver Federal Center,

Denver, CO 80225, E-mail: (smahan @ usgs.gov)

The use of firm, trade, and brand names is for identification purposes only and does not constitute endorsement by the U.S. government.

Jose Luis Antinao Rojas - (Earth and Ecosystems Sciences,Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512-1095, [email protected] ) specializes in all geologicalapplications.

Jose Antinao Professional Page E.L. Cord Geochronology Laboratory
http://answers.usgs.gov/cgi-bin/gsanswers?pemail=smahan&subject=Luminescence+Lab+Inquiryhttp://answers.usgs.gov/cgi-bin/gsanswers?pemail=smahan&subject=Luminescence+Lab+Inquiryhttp://answers.usgs.gov/cgi-bin/gsanswers?pemail=smahan&subject=Luminescence+Lab+Inquirymailto:[email protected]:[email protected]:[email protected]://www.dri.edu/jose-antinaohttp://www.dri.edu/jose-antinaohttp://www.dri.edu/dees-laboratories/1742-el-cord-geochronology-laboratoryhttp://www.dri.edu/dees-laboratories/1742-el-cord-geochronology-laboratoryhttp://www.dri.edu/dees-laboratories/1742-el-cord-geochronology-laboratoryhttp://www.dri.edu/jose-antinaomailto:[email protected]://answers.usgs.gov/cgi-bin/gsanswers?pemail=smahan&subject=Luminescence+Lab+Inquiry


16/18

Victor Bortolot - (Daybreak Nuclear and Medical Systems, 50Denison Drive, Guilford, CT 06437 ,[email protected] )specializes in building luminescence software and as well asequipment to run samples on. Also an art and ceramic authenticatorusing TL, certified.

George Brook / Pradeep Srivastava - (University of Georgia,Dept. of Geography, Athens, GA 30602 ,[email protected] ) allgeological applications.

George Brook Professional Page The University of Georgia Luminescence Dating Laboratory

James Feathers - (University of Washington, Dept. of Anthropology, Box 353100, Seattle, WA 98195-3100 , [email protected] ) specializes in archeologicalapplications.

University of Washington Luminescence Dating Laboratory

Steven Forman / James Pierson - (Dept. of Earth andEnvironmental Sciences, University of Illinois, 845 W. Taylor St.,Chicago, IL 60607-7059, [email protected] ) specializes in all geologicalapplications. (Mississippi river Valley, Canada and other Arctic circlecountries, western U.S.)

The University of Illinois at Chicago Luminescence DatingResearch Laboratory

Ron Goble / Paul Hanson / Aaron Young - (University of Nebraska, Lincoln, NE, [email protected] ) specializes in Nebraskasands, soils and loess and other Mid-West features or geologicaldating projects linked to the University.

Ron Goble Dept. of Geosciences Page Paul Hanson Professional Page Aaron Young Professional Page

Michel Lamothe - (University of Quebec in Montral,

Canada, [email protected] ) Michel Lamothe Professional Page Laboratory Site

Ken Lepper - (North Dakota State University). Specializes ingeological applications as well as being the first proponent of the"leading edge" analytical method. Can be found at Fargo, NorthDakota 701-231-6746 or e-mail [email protected] .

Olav Lian - (University of the Fraser Valley, Abbotsford, B.C.,Canada, [email protected] )

Olav Lian's Professional Page
mailto:[email protected]:[email protected]:[email protected]:[email protected]://www.ggy.uga.edu/brook/http://www.ggy.uga.edu/brook/http://www.uga.edu/osl/http://www.uga.edu/osl/mailto:[email protected]:[email protected]://depts.washington.edu/lumlab/http://depts.washington.edu/lumlab/mailto:[email protected]:[email protected]:[email protected]://www.uic.edu/labs/ldrl/http://www.uic.edu/labs/ldrl/http://www.uic.edu/labs/ldrl/http://www.uic.edu/labs/ldrl/http://www.uic.edu/labs/ldrl/mailto:[email protected]:[email protected]://www.geosciences.unl.edu/people/faculty_page.php?lastname=Goble&firstname=Ronald&type=REGhttp://www.geosciences.unl.edu/people/faculty_page.php?lastname=Goble&firstname=Ronald&type=REGhttp://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=758http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=758http://snr.unl.edu/aboutus/who/people/staff-member.asp?pid=791http://snr.unl.edu/aboutus/who/people/staff-member.asp?pid=791mailto:[email protected]:[email protected]:[email protected]://scta.uqam.ca/component/content/article/7-professeur/37-michel-lamothe.htmlhttp://scta.uqam.ca/component/content/article/7-professeur/37-michel-lamothe.htmlhttp://lux.uqam.ca/http://lux.uqam.ca/mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]://www.ufv.ca/geography/People/Faculty_and_Staff/Olav_Lian_s_Webpage.htmhttp://www.ufv.ca/geography/People/Faculty_and_Staff/Olav_Lian_s_Webpage.htmhttp://www.ufv.ca/geography/People/Faculty_and_Staff/Olav_Lian_s_Webpage.htmmailto:[email protected]:[email protected]://lux.uqam.ca/http://scta.uqam.ca/component/content/article/7-professeur/37-michel-lamothe.htmlmailto:[email protected]://snr.unl.edu/aboutus/who/people/staff-member.asp?pid=791http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=758http://www.geosciences.unl.edu/people/faculty_page.php?lastname=Goble&firstname=Ronald&type=REGmailto:[email protected]://www.uic.edu/labs/ldrl/http://www.uic.edu/labs/ldrl/mailto:[email protected]://depts.washington.edu/lumlab/mailto:[email protected]://www.uga.edu/osl/http://www.ggy.uga.edu/brook/mailto:[email protected]:[email protected]


17/18

Luminescence Dating Laboratory

Carl Lipo - (California State University, LongBeach, CA, [email protected] ) Dept. of Anthropology, CSU LongBeach, 1250 Bellflower Blvd., Long Beach, CA 90840, 562-985-2393. Specializes in archaeological applications.

Carl Lipo's Professional Page Lipo Laboratory Site The Institute for Integrated Research in Materials,

Environments, and Society (IIRMES) Luminescence Dating

Steve McKeever / Regina DeWitt - (Oklahoma State University,Dept. of Physics, 145 Physical Science Bdlg.,Stillwater, OK 74078, [email protected] ) specializesin theory and physics of luminescence along with solid-state TL, andMars luminescence applications.

Stephen McKeever Professional Page Regina DeWitt Professional Page Oklahoma State University Radiation Dosimetry Laboratory

Lewis Owen - (University of Cincinnati,OH, [email protected] ) Dept. of Geology, P.O. Box 210013,Cincinnati, OH 45221-0013. Glacial and glacially-reworkedsediments. Specializes in Himalayan geology using luminescenceand cosmogenic dating.

Lewis Owen Professional Page Vasilis Pagonis - (McDaniel College,

Westminster, MD, [email protected] ) Vasilis Pagonis Professional Page Thermoluminescence Research Information

Ed Rhodes - (University of California, Los Angeles, Dept. of Earthand Space Sciences, Los Angeles, CA ,[email protected] )

Ed Rhodes Professional Page

Jack Rink - (McMaster University, Hamilton, Ontario,Canada, [email protected] )

Jack Rink Faculty Page | Jack Rink AGE Lab Page AGE Laboratory

Tammy Rittenour - (Utah State University,Logan, UT, [email protected] )

Utah State University Luminescence Laboratory USU Research Matters 2009 Article
http://www.ufv.ca/geography/Research_Labs/Research_Facilities/Luminescence_Dating_Lab.htmhttp://www.ufv.ca/geography/Research_Labs/Research_Facilities/Luminescence_Dating_Lab.htmmailto:[email protected]:[email protected]:[email protected]://www.lipolab.org/lipo.htmlhttp://www.lipolab.org/lipo.htmlhttp://www.lipolab.org/lab_and_research.htmlhttp://www.lipolab.org/lab_and_research.htmlhttp://www.iirmes.org/Home/luminescence-datinghttp://www.iirmes.org/Home/luminescence-datinghttp://www.iirmes.org/Home/luminescence-datinghttp://www.iirmes.org/Home/luminescence-datinghttp://www.iirmes.org/Home/luminescence-datingmailto:[email protected]:[email protected]:[email protected]://regentsprofessors.okstate.edu/regents-professors/39-c-mckeever-stephenhttp://regentsprofessors.okstate.edu/regents-professors/39-c-mckeever-stephenhttp://www.ecu.edu/cs-cas/physics/Regina-Dewitt.cfmhttp://www.ecu.edu/cs-cas/physics/Regina-Dewitt.cfmhttp://physics.okstate.edu/yukihara/dosimetry/http://physics.okstate.edu/yukihara/dosimetry/mailto:[email protected]:[email protected]:[email protected]://www.artsci.uc.edu/collegemain/faculty_staff/profile_details.aspx?ePID=MTA5NjI3http://www.artsci.uc.edu/collegemain/faculty_staff/profile_details.aspx?ePID=MTA5NjI3mailto:[email protected]:[email protected]://blog.mcdaniel.edu/vasilispagonis/dr-vasilis-pagonis-2/http://blog.mcdaniel.edu/vasilispagonis/dr-vasilis-pagonis-2/http://www2.mcdaniel.edu/Physics/TLwebsite/manylinks.htmlhttp://www2.mcdaniel.edu/Physics/TLwebsite/manylinks.htmlmailto:[email protected]:[email protected]:[email protected]://www.ess.ucla.edu/people/faculty/574/http://www.ess.ucla.edu/people/faculty/574/mailto:[email protected]:[email protected]://sciwebserver.science.mcmaster.ca/geo/faculty/rink/index.htmlhttp://sciwebserver.science.mcmaster.ca/geo/faculty/rink/index.htmlhttp://www.science.mcmaster.ca/geo/research/age/jack_home.htmhttp://www.science.mcmaster.ca/geo/research/age/jack_home.htmhttp://www.science.mcmaster.ca/geo/research/age/jack_home.htmhttp://www.science.mcmaster.ca/geo/research/age/aboutage.htmhttp://www.science.mcmaster.ca/geo/research/age/aboutage.htmmailto:[email protected]:[email protected]:[email protected]://www.usu.edu/geo/luminlab/http://www.usu.edu/geo/luminlab/http://research.usu.edu/researchmatters2009/htm/luminoushttp://research.usu.edu/researchmatters2009/htm/luminoushttp://research.usu.edu/researchmatters2009/htm/luminoushttp://www.usu.edu/geo/luminlab/mailto:[email protected]://www.science.mcmaster.ca/geo/research/age/aboutage.htmhttp://www.science.mcmaster.ca/geo/research/age/jack_home.htmhttp://sciwebserver.science.mcmaster.ca/geo/faculty/rink/index.htmlmailto:[email protected]://www.ess.ucla.edu/people/faculty/574/mailto:[email protected]://www2.mcdaniel.edu/Physics/TLwebsite/manylinks.htmlhttp://blog.mcdaniel.edu/vasilispagonis/dr-vasilis-pagonis-2/mailto:[email protected]://www.artsci.uc.edu/collegemain/faculty_staff/profile_details.aspx?ePID=MTA5NjI3mailto:[email protected]://physics.okstate.edu/yukihara/dosimetry/http://www.ecu.edu/cs-cas/physics/Regina-Dewitt.cfmhttp://regentsprofessors.okstate.edu/regents-professors/39-c-mckeever-stephenmailto:[email protected]://www.iirmes.org/Home/luminescence-datinghttp://www.iirmes.org/Home/luminescence-datinghttp://www.lipolab.org/lab_and_research.htmlhttp://www.lipolab.org/lipo.htmlmailto:[email protected]://www.ufv.ca/geography/Research_Labs/Research_Facilities/Luminescence_Dating_Lab.htm


18/18

Zhixiong Shen - (Tulane University, NewOrleans, LA, [email protected] ) no laboratory but OSL expertise

Zhixiong Shen Professional Page

Joel Spencer - (Kansas State UniversityManhattan, KS, [email protected] )

Joel Spencer Department of Geology Faculty Page

Cathy Wilson - (Los Alamos National Labs in New Mexico for theEnvironmental Sciences Group). Specializes in New Mexico orientedprojects as well as dosimetry projects. Can be found at LANL, EES-10, MS J995, Los Alamos, NM 87545 or e-mail [email protected] .

Los Alamos National Laboratory Luminescence GeochronologyLab

Hong Wang - (Geochronology Laboratory, Illinois State GeologicalSurvey, Champaign,IL ,[email protected] )

Hong Wang Professional Page
mailto:[email protected]:[email protected]:[email protected]://tulane.edu/sse/eens/faculty-and-staff/shen.cfmhttp://tulane.edu/sse/eens/faculty-and-staff/shen.cfmmailto:[email protected]:[email protected]://www.k-state.edu/geology/faculty-staff/Spencer.htmlhttp://www.k-state.edu/geology/faculty-staff/Spencer.htmlmailto:[email protected]:[email protected]:[email protected]://ees.lanl.gov/osl.shtmlhttp://ees.lanl.gov/osl.shtmlhttp://ees.lanl.gov/osl.shtmlhttp://ees.lanl.gov/osl.shtmlhttp://ees.lanl.gov/osl.shtmlmailto:[email protected]:[email protected]:[email protected]://www.isgs.illinois.edu/about-isgs/staff-dir/w/wang.shtmlhttp://www.isgs.illinois.edu/about-isgs/staff-dir/w/wang.shtmlhttp://www.isgs.illinois.edu/about-isgs/staff-dir/w/wang.shtmlmailto:[email protected]://ees.lanl.gov/osl.shtmlhttp://ees.lanl.gov/osl.shtmlmailto:[email protected]://www.k-state.edu/geology/faculty-staff/Spencer.htmlmailto:[email protected]://tulane.edu/sse/eens/faculty-and-staff/shen.cfmmailto:[email protected]

Documents

TL and OSL