Technical specification for thermoluminescence dating of the ancient ceramics
Some standard content:
ICS03.080.99
National Standard of the People's Republic of China
GB/T37909—2019
Technical specification for thermoluminescence dating of ancient ceramics theancientceramics
Released on 2019-08-30
State Administration for Market Regulation
Standardization Administration of the People's Republic of China
Implemented on 2019-08-30
Terms and definitions
Ancient dose measurement of pottery
Ancient dose measurement of porcelain
Measurement and calculation of annual dose
Calibration of laboratory radioactive sources
Error in thermoluminescence dating of ancient ceramics
Data processing and reporting
Appendix A (Normative Appendix)
Appendix B (Normative Appendix)
Appendix C (Normative Appendix)
Appendix D (Normative Appendix)
Appendix E (Normative Appendix)
Appendix F (Informative Appendix)
Appendix G (Informative Appendix)
Appendix H (Informative Appendix)
Appendix I (Informative Appendix)
References
Method for measuring ancient doses of pottery using fine particle technology Measurement and calculation of ancient doses of porcelain
Measurement of annual doses of needles and uranium using thick source α particle counting method Measurement of environmental dose rates of ancient sites using thermoluminescent dosimeters Calculation of errors in thermoluminescent dating…
Sampling registration form for thermoluminescent dating of ancient ceramics Record form for thermoluminescent dating of pottery samples Record form for thermoluminescent dating of porcelain samples·Report on thermoluminescent dating of ancient ceramics
GB/T37909—2019
This standard was drafted in accordance with the rules given in GB/T1.1-—2009. This standard was proposed by the State Administration of Cultural Heritage.
This standard is under the jurisdiction of the National Technical Committee for Cultural Relics Protection Standardization (SAC/TC289). Drafting unit of this standard: Shanghai Museum
Main drafters of this standard: Xia Junding, Wu Jingwei, Wang Weida, Xiong Yingfei, Gong Yuwu. GB/T37909—2019
1 Scope
Technical specification for thermoluminescence dating of ancient ceramics GB/T37909—2019
This standard specifies the terms and definitions of thermoluminescence dating of ancient ceramics, ancient pottery dose measurement, ancient porcelain dose measurement, annual dose measurement and calculation, laboratory radioactive source calibration, errors in thermoluminescence dating of ancient ceramics, and data processing and reporting. This standard is applicable to thermoluminescence dating and authenticity identification of ancient ceramics. Terms and definitions
The following terms and definitions apply to this document. 2.1
Pottery
Utensils made of clay as the main raw material, after molding, drying and other processes, and fired at a temperature of about 800℃~1150℃. 2.2
porcelain
Articles made of one or more natural minerals rich in silicon, after batching, molding, drying and other processes, with or without glaze on the surface, fired in a kiln at a high temperature of about 1150℃～1350℃. 2.3bZxz.net
phosphor
Mineral crystals such as quartz with luminescent properties. 2.4
thermoluminescence dating
thermoluminescence dating
The time from the last heating of a ceramic sample to the time of measurement is measured by the phenomenon that the radiation energy accumulated in the phosphor is converted into light energy by heating.
accumulated dose
The natural radiation dose absorbed by a ceramic sample from the last heating to the time of measurement. 2.6
equivalent beta dose
equivalent beta dose
equivalent alpha dose
equivalent alpha dose
equivalent alpha dose
equivalent alpha dose 2.8
environmental dose
environmental dose
consists of radiation in the soil of the buried environment and cosmic rays c, which together provide radioactive doses to ceramic samples. GB/T37909—2019
calibratingdose
standard dose of laboratory radioactive source irradiation for the relationship between thermoluminescence intensity and dose per unit time. 2.10
test dose
in the pre-dose dating technique, the dose used to induce the 110℃ thermoluminescence peak of porcelain samples. 2.11
alpha effectiveness
The ratio of the alpha irradiation dose per gray to the beta (or) irradiation dose per gray in induced thermoluminescence. 2.12
supralinearity correction value supralinearitycorrectionThe value obtained by correcting the equivalent dose that is under-counted (or over-counted) by using a fixed sensitivity in the small-dose nonlinear part. 2.13
paleodose
The total radioactive dose received by ceramics after firing. 2.14
plateauarea
The ratio of natural thermoluminescence to calibrated dose thermoluminescence, the temperature area in the curve where the ratio is relatively stable with temperature 2.15
fine-grain techniquefine-grain techniqueThe technique of using mineral particles such as quartz with a diameter of 3μm to 8um naturally existing in pottery samples as a measure of the equivalent dose of the sample. 2.16
quartz inclusion technique is a technique that uses quartz particles with a diameter of about 100um that exist naturally in pottery samples as a measure of the equivalent dose of the sample. 2.17
pre-dosedating technique is a technique that uses the pre-dose effect of the 110℃ thermoluminescence peak of quartz to determine the ancient dose of ceramic samples. 2.18
thermal activation
the process of heating the porcelain sample to a temperature that can increase the sensitivity of the 110℃ thermoluminescence peak to the highest activation temperature. 2.19
radiation quenching
the phenomenon that the sensitivity of the 110℃ thermoluminescence peak of porcelain samples will decrease when irradiated by radioactive isotopes. 2.20
Activation methodactivationmethod
In the pre-dose measurement period of porcelain, the method of calculating the ancient dose based on the saturation exponential relationship between the thermal activation sensitivity of the quartz 110℃ thermoluminescence peak and the radiation source irradiation dose.
Quenching methodquenchingmethod
In the pre-dose measurement period of porcelain, the method of calculating the ancient dose based on the saturation exponential relationship between the thermal activation sensitivity and radiation quenching sensitivity of the quartz 110℃ thermoluminescence peak and the radiation source irradiation dose. 2
Annual dose
annualdose
The radiation dose received by ceramics in one year.
Note: The unit is milligray per year (mGy/a). 2.23
Correction of moisture content
The process of correcting the dose absorbed by water in ceramics and soil. 2.24
Thick-source alpha counting method
Thick-source alpha counting method is a technique for obtaining the annual dose of Th and U in a sample by measuring the alpha particle counting rate of a thick sample. 2.25
thermoluminescenceage
Thermoluminescence age
Age from present
The number of years from the last time the ceramic sample was heated to the time of determination. A=D
Where:
A——thermoluminescence age, in years (a); P——ancient dose, in gray (Gy) or milligray (mGy); D
annual dose, in gray per year (Gya) or milligray per year (mGy/a). Calibration dose
calibrating dose
GB/T 37909—2019
The ratio of the thermoluminescence of a ceramic sample to the standard dose thermoluminescence of a laboratory radiation source irradiation is used to determine the relationship between the thermoluminescence of this sample and the standard dose, and obtain the thermoluminescence sensitivity of the sample. 2.27
Offset dose
Offset dose
In an alpha or beta source automatic irradiator, the increase or decrease in dose caused by the difference between the automatic timing and the actual irradiation time of the sample.
absorbed dose
Absorbed dose
The dose absorbed by a unit mass of material after being irradiated. Note: The unit is gray per gram (Gy/g).
Thick source thick source
The thickness of the pottery body is much greater than the range of alpha particles in it. The alpha emitter in the pottery body is a specific radiation source. 2.30
Thermoluminescence dating system
thermoluminescence dating system A device for measuring the thermoluminescence age of ceramic samples. 2.31
Vacuum/nitrogen system
A device for suppressing thermoluminescence caused by non-radiation by first evacuating the instrument sample measurement chamber and then passing nitrogen, and for controlling the irradiation switch of the radiation source.
GB/T37909—2019
Thermoluminescence countsIntegrate and count the area of the thermoluminescence curve in a certain temperature range. 3 Pottery ancient dose measurement
Fine particle technology
3.1.1 Preparation of fine particle samples
The preparation of fine particle samples is divided into acetone flotation method and water flotation method, see Appendix A. The samples taken from the pottery body are crushed, screened and floated to obtain mineral particle samples such as quartz with a diameter of 3m to 8m. Then they are suspended and precipitated on a disc with a diameter of 9.5mm. The sample thickness is not more than 10um. 3.1.2 Measurement and calculation of equivalent dose Q, equivalent α dose Q and α relative thermoluminescence efficiency a of samples Use mathematical equations to make linear regression for the relationship between the thermoluminescence intensity and dose of three groups of natural thermoluminescence, natural thermoluminescence with β dose and natural thermoluminescence with 2β dose. Obtain the linear correlation coefficient and equivalent dose Q from the linear equation. Use the same method to obtain the equivalent α dose Q from the linear regression of the other three groups of thermoluminescence intensities with α dose. α thermoluminescence relative efficiency a=Q/Q.
For specific measurement methods, see Appendix A.
3.1.3 Measurement of superlinear correction value I
Take 5 samples that have been measured for natural thermoluminescence, irradiate them with doses from 1β to 5β respectively, and measure the second thermoluminescence curves of the 5 samples. Make linear regression between thermoluminescence intensity and β dose, and obtain superlinear correction value from extrapolation or linear equation. 3.1.4 Calculation of pottery paleo-dose (fine particle method) is equal to equivalent dose plus super-linear correction, that is, P=Q+I
Where:
P paleo-dose, in gray (Gy) or milligray (mGy); Q equivalent dose, in gray (Gy) or milligray (mGy); I—super-linear correction value, in gray (Gy) or milligray (mGy). 3.2 Coarse-grained quartz technology
3.2.1 Quartz sample preparation
Pottery fragments are crushed and screened to obtain 200 mg of mineral particle samples with a diameter of 80um~120um, and the α dose on the surface is removed by HF, and the magnetic material is removed by a magnetic separator. A quartz particle sample of not less than 100 mg is taken for standby use. 3.2.2 Determination of equivalent dose 0
Weigh 10 mg of the prepared coarse-grained quartz sample each time and measure the natural thermoluminescence and natural laboratory β to 5β dose thermoluminescence of the sample respectively. Perform linear regression on their thermoluminescence intensity and β dose data, and obtain the linear correlation coefficient and equivalent dose Q from the linear regression equation.
3.2.3 Measurement of superlinear correction value I
The same as the fine particle method (see 3.1.3).
3.2.4 Calculation of pottery ancient dose (coarse-grained quartz method) The same as the fine particle method (see 3.1.4).
4 Porcelain ancient dose measurement
Porcelain ancient dose P
GB/T37909—2019
The ancient dose of porcelain is mainly composed of β dose provided by uranium (U), thorium (Th), potassium (K) in the porcelain body, γ dose provided by the environment, and cosmic ray c. The α dose is negligible because it is extremely small in the pre-dose technique and is attenuated by the thickness of the thin slice sample and the diameter of the particle sample. 4.2 Preparation of porcelain samples
Porcelain samples are prepared into samples that meet the requirements of thermoluminescence measurement. The porcelain thin slice method or the large particle method is usually used. See Appendix B.
4.3 Pre-dose saturation index method
4.3.1 Pre-dose technique
Porcelain samples are heated to the activation temperature at a certain rate in the laboratory. Even if the same test dose is irradiated, the sensitivity of the thermoluminescence peak generated at 110℃ will vary depending on the dose previously applied. The larger the dose previously applied, the larger the induced thermoluminescence, and vice versa. This positive correlation between the thermoluminescence generated by the test dose and the previously applied dose is called the "pre-dose effect". When the porcelain sample is heated to the activation temperature, the thermoluminescence sensitivity of the next test dose received will increase significantly. This increase is proportional to the total dose received by the sample before activation, i.e., the paleo-dose, or the dose added between two activations, i.e., the calibrated dose. The calculation of the paleodose by using the increased thermoluminescence sensitivity between the two test doses is called the “pre-dose technique”. 4.3.2 Thermal Activation Characteristic (TAC) Test
Take the prepared porcelain sample and heat it every 50°C from 200°C until 700°C. Measure the sensitivity S after each heating and draw a curve of sensitivity changing with heating temperature, i.e., the TAC curve of the sample. 4.3.3 Calculate the paleodose according to the saturation exponential function 4.3.3.1 Calculate the paleodose by activation method
The calculation formula of paleodose P is:
P=-BIn(1-
Where. S.=-a/b
B=-β/ln(1+6)
Where:
- paleodose, in gray (Gy) or milligray (mGy); B
constant, in gray (Gy) or milligray (mGy); S—natural cumulative dose activation sensitivity, in ampere per watt (A/W); S.
original sensitivity, in ampere per watt (A/W); ··（3）
............( 4 )
·.·（5)
GB/T37909—2019
Saturation sensitivity, in ampere per watt (A/W); intercept of the linear function of sensitivity change;
slope of the linear function of sensitivity change;
calibrated dose, in gray (Gy) or milligray (mGy); test dose, in gray (Gy) or milligray (mGy). Extinction method for ancient dose
The ancient dose calculation formula of the extinction method is the same as that of the activation method, except that the meaning of the parameters is different. See Appendix B. Extinction rate determination
After the porcelain sample receives a laboratory beta irradiation dose, its sensitivity decreases, which is called "extinguishing". The extinction rate is calculated according to the following formula:||t t||Where:
Extinction rate, %;
(S+IS.)1
S,+1—Extinction sensitivity of the ith plus 1st step, in amperes per watt (A/W); S
Sensitivity of the ith step, in amperes per watt (A/W); Calibrated dose of laboratory irradiation, in gray (Gy) or milligray (mGy). 5. Measurement and calculation of annual dose
5.1 Annual dose
（6）
The annual dose of ceramics is mainly composed of the α dose and β dose provided by U and Th in the sample, the β dose provided by K, the dose provided by the environment and the cosmic ray dose.
Annual dose calculation formula:
D=[D.+D&Th+u) +D&K) +D+e]
Wherein:
DgTh+U)
annual dose, in gray per year (Gy/a) or milligray per year (mGy/a); α annual dose provided by U and Th, in gray per year (Gy/a) or milligray per year (mGy/a); β annual dose provided by U and Th, in gray per year (Gy/a) or milligray per year (mGy/a); β annual dose provided by tK, in gray per year (Gy/a) or milligray per year (mGy/a); (7)
annual dose provided by the environment and annual dose of cosmic rays, in gray per year (Gy/a) or milligray per year (mGy/a). 5.2 Determination of K content
Measure the potassium content in the sample by neutron activation analysis, atomic absorption spectrophotometer, ion chromatograph or flame photometer analysis.
5.3 Determination of U and Th content
The annual dose of U and Th is measured by thick source alpha particle counting method, see Appendix C. 5.4 Determination and correction of moisture content
The pottery samples collected from the site are sealed, weighed in the laboratory, dried, and weighed again, and the weight of water is obtained by subtracting. The moisture content W is obtained by the ratio of water 6
GB/T37909—2019
to the weight of the dry sample, and the moisture content is corrected using Zimmerman's three formulas. D.
D,=1+1.14W'F
Wherein:
α annual dose for moist samples, in gray per year (Gy/a) or milligray per year (mGy/a); α annual dose for dry samples, in gray per year (Gy/a) or milligray per year (mGy/a); moisture content of pottery, %;
groundwater fluctuation factor;
β annual dose for moist samples, in gray per year (Gy/a) or milligray per year (mGy/a); The annual dose of β for dry samples is in Gy/a or mGy/a; the annual dose for wet samples is in Gy/a or mGy/a; the annual dose for dry samples is in Gy/a or mGy/a; the soil moisture content at the site where the pottery was unearthed is %.
5.5 Thermoluminescent dosimeter (TLD) measures the environmental dose rate at archaeological sites (8)
. (10)
Bury the thermoluminescent dosimeter within a radius of 30 cm from the site where the pottery sample was unearthed. The burial time is 3 months to 1 year. It is used to measure the radioactive dose in the environment. See Appendix D. Calibration of laboratory radioactive sources
6.1 β source (9Sr/9Y)
6.1.1 β source in thermoluminescent instrument
It is usually a round metal plate source. Sr has a half-life of 28 years and a maximum energy of only 0.54MeV. Its daughter \Y has a half-life of 64h and a maximum energy of 2.26MeV.
6.1.2 Calibration with dose
Irradiate the thermoluminescent dose element with a source of known radioactive dose to calibrate the β source and transfer the Y dose to the β source. 6.1.3 Calibration with a calibrated natural uranium block
Irradiate the thermoluminescent dose element with a natural uranium block of known radioactive dose to calibrate the β source and obtain the irradiation dose rate of this β source. 6.2α source (241Am or 244Cm)
6.2.1α source in thermoluminescence instrument
α sources used in thermoluminescence dating of ancient ceramics mainly use 241Am and 24*Cm. 6.2.2α source calibration
Use CaSO4:Tm ultra-thin thermoluminescent dose element to calibrate an α source with known intensity S to another α source with unknown intensity. Intensity S is the total track length density per unit time when α particles pass through quartz, unit: um-2/minGB/T37909—2019
Error in thermoluminescence dating of ancient ceramics
The calculation method of thermoluminescence dating error is shown in Appendix E. 8
Data processing and reporting
Sampling registration
Pottery and porcelain samples should be registered on their own forms after sampling. For the specific format, please refer to Appendix F Dating Record
When thermoluminescence dating of pottery, the pottery thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix G.
When thermoluminescence dating of porcelain, the porcelain thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix H.
3 Age determination report
Thermoluminescence age determination report, see Appendix 1 for the specific format. 8
A.1 Overview
Appendix A
(Normative Appendix)
Method for measuring ancient dose of pottery using fine particle technology GB/T37909—2019
The fine particle technology selects particles with a diameter of 3um~8μm that naturally exist in the sample as samples for measuring ancient dose. It mainly considers the range of α particles in pottery. The range of α particles in pottery is 15μm~50μm. Only particles with a diameter of less than 10μm can be completely penetrated by α rays, and the dose received is not significantly attenuated. A.2 Sample preparation
Acetone flotation method
A.2.1.1 Use tools to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for use. Avoid heating the sample during crushing and avoid violent impact on the sample. A.2.1.2 Take 400mg of fine particle sample and put it into a 150mL beaker, and use acetone flotation. A.2.1.3 Use a beaker, add acetone to a height of 60mm, shake the beaker and put it into an ultrasonic bath for several minutes. After the beaker is left to stand for 2min, pour the suspension into another beaker, and let it stand for another 20min. Pour out the suspension, and the particles left in the beaker are the fine particle samples needed for dating.
A.2.1.4 Take 30 flat-bottomed test tubes with a diameter of 11mm, and put a 9.5mm diameter stainless steel disc or aluminum disc (hereinafter referred to as disc) in each test tube. In the beaker containing the fine particle sample, pour acetone to suspend the fine particles evenly. Use a burette to take an equal amount of the suspension and inject it into the test tube containing the disc
A.2.1.5 Stand 30 test tubes upright on a test tube rack and put them in a drying oven at 50°C. After the fine particles are completely precipitated on the disc, use a siphon to suck out most of the acetone, and then let the acetone evaporate naturally in the drying oven. After drying, the disc sample is taken out of the test tube. Prepare a disc sample by precipitation in each test tube. Prepare the number of samples according to the measurement needs. A.2.2 Water flotation method
A.2.2.1 Use a tool to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for standby use. Avoid heating the sample during crushing and avoid the sample from receiving severe impact. A.2.2.2 Place 400 mg of sample in a 150 mL beaker and use distilled water for flotation. A.2.2.3 Add distilled water to a height of 70 mm. After stirring, let the beaker stand for 10 minutes. At this time, particles with a diameter greater than 8 μm have settled to the bottom of the beaker, and particles with a diameter less than 8 μm are suspended. A.2.2.4 Slowly pour the suspension in this beaker into another 150 mL beaker and let it stand for 60 minutes. After 60 minutes, the particles still suspended are all less than 3 μm in diameter.
A.2.2.5 Pour out the suspension with particles less than 3 μm. What remains in the beaker is a fine particle sample of 3 μm to 8 μm. The suspension and sedimentation times of 10 minutes and 60 minutes, respectively, are approximate values calculated based on Stokes formula (A.1). 9nh
2(pp）gr
Wherein:
S—suspension and sedimentation time, in seconds (s); n—viscosity coefficient of water at 20°C, in Pascal seconds (Pa·s); (Al)4 Determination and correction of moisture content
The pottery samples collected from the site are sealed, weighed in the laboratory, dried, and weighed again, and the weight of water is obtained by subtracting. The moisture content W is obtained by the ratio of water 6
GB/T37909—2019
to the weight of the dry sample, and the moisture content is corrected using Zimmerman's three formulas. D.
D,=1+1.14W'F
Where:
α annual dose of moist samples, in gray per year (Gy/a) or milligray per year (mGy/a); α annual dose of dry samples, in gray per year (Gy/a) or milligray per year (mGy/a); pottery moisture content, %;
groundwater fluctuation factor;
β annual dose of moist samples, in units of The annual dose of β for dry samples is in Gy/a or mGy/a; the annual dose for wet samples is in Gy/a or mGy/a; the annual dose for dry samples is in Gy/a or mGy/a; the soil moisture content at the site where the pottery was unearthed is %.
5.5 Thermoluminescent dosimeter (TLD) measures the environmental dose rate at archaeological sites (8)
. (10)
Bury the thermoluminescent dosimeter within a radius of 30 cm from the site where the pottery sample was unearthed. The burial time is 3 months to 1 year. It is used to measure the radioactive dose in the environment. See Appendix D. Calibration of laboratory radioactive sources
6.1 β source (9Sr/9Y)
6.1.1 β source in thermoluminescent instrument
It is usually a round metal plate source. Sr has a half-life of 28 years and a maximum energy of only 0.54MeV. Its daughter \Y has a half-life of 64h and a maximum energy of 2.26MeV.
6.1.2 Calibration with dose
Irradiate the thermoluminescent dose element with a source of known radioactive dose to calibrate the β source and transfer the Y dose to the β source. 6.1.3 Calibration with a calibrated natural uranium block
Irradiate the thermoluminescent dose element with a natural uranium block of known radioactive dose to calibrate the β source and obtain the irradiation dose rate of this β source. 6.2α source (241Am or 244Cm)
6.2.1α source in thermoluminescence instrument
α sources used in thermoluminescence dating of ancient ceramics mainly use 241Am and 24*Cm. 6.2.2α source calibration
Use CaSO4:Tm ultra-thin thermoluminescent dose element to calibrate an α source with known intensity S to another α source with unknown intensity. Intensity S is the total track length density per unit time when α particles pass through quartz, unit: um-2/minGB/T37909—2019
Error in thermoluminescence dating of ancient ceramics
The calculation method of thermoluminescence dating error is shown in Appendix E. 8
Data processing and reporting
Sampling registration
Pottery and porcelain samples should be registered on their own forms after sampling. For the specific format, please refer to Appendix F Dating Record
When thermoluminescence dating of pottery, the pottery thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix G.
When thermoluminescence dating of porcelain, the porcelain thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix H.
3 Age determination report
Thermoluminescence age determination report, see Appendix 1 for the specific format. 8
A.1 Overview
Appendix A
(Normative Appendix)
Method for measuring ancient dose of pottery using fine particle technology GB/T37909—2019
The fine particle technology selects particles with a diameter of 3um~8μm that naturally exist in the sample as samples for measuring ancient dose. It mainly considers the range of α particles in pottery. The range of α particles in pottery is 15μm~50μm. Only particles with a diameter of less than 10μm can be completely penetrated by α rays, and the dose received is not significantly attenuated. A.2 Sample preparation
Acetone flotation method
A.2.1.1 Use tools to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for use. Avoid heating the sample during crushing and avoid violent impact on the sample. A.2.1.2 Take 400mg of fine particle sample and put it into a 150mL beaker, and use acetone flotation. A.2.1.3 Use a beaker, add acetone to a height of 60mm, shake the beaker and put it into an ultrasonic bath for several minutes. After the beaker is left to stand for 2min, pour the suspension into another beaker, and let it stand for another 20min. Pour out the suspension, and the particles left in the beaker are the fine particle samples needed for dating.
A.2.1.4 Take 30 flat-bottomed test tubes with a diameter of 11mm, and put a 9.5mm diameter stainless steel disc or aluminum disc (hereinafter referred to as disc) in each test tube. In the beaker containing the fine particle sample, pour acetone to suspend the fine particles evenly. Use a burette to take an equal amount of the suspension and inject it into the test tube containing the disc
A.2.1.5 Stand 30 test tubes upright on a test tube rack and put them in a drying oven at 50°C. After the fine particles are completely precipitated on the disc, use a siphon to suck out most of the acetone, and then let the acetone evaporate naturally in the drying oven. After drying, the disc sample is taken out of the test tube. Prepare a disc sample by precipitation in each test tube. Prepare the number of samples according to the measurement needs. A.2.2 Water flotation method
A.2.2.1 Use a tool to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for standby use. Avoid heating the sample during crushing and avoid the sample from receiving severe impact. A.2.2.2 Place 400 mg of sample in a 150 mL beaker and use distilled water for flotation. A.2.2.3 Add distilled water to a height of 70 mm. After stirring, let the beaker stand for 10 minutes. At this time, particles with a diameter greater than 8 μm have settled to the bottom of the beaker, and particles with a diameter less than 8 μm are suspended. A.2.2.4 Slowly pour the suspension in this beaker into another 150 mL beaker and let it stand for 60 minutes. After 60 minutes, the particles still suspended are all less than 3 μm in diameter.
A.2.2.5 Pour out the suspension with particles less than 3 μm. What remains in the beaker is a fine particle sample of 3 μm to 8 μm. The suspension and sedimentation times of 10 minutes and 60 minutes, respectively, are approximate values calculated based on Stokes formula (A.1). 9nh
2(pp）gr
Wherein:
S—suspension and sedimentation time, in seconds (s); n—viscosity coefficient of water at 20°C, in Pascal seconds (Pa·s); (Al)4 Determination and correction of moisture content
The pottery samples collected from the site are sealed, weighed in the laboratory, dried, and weighed again, and the weight of water is obtained by subtracting. The moisture content W is obtained by the ratio of water 6
GB/T37909—2019
to the weight of the dry sample, and the moisture content is corrected using Zimmerman's three formulas. D.
D,=1+1.14W'F
Where:
α annual dose of moist samples, in gray per year (Gy/a) or milligray per year (mGy/a); α annual dose of dry samples, in gray per year (Gy/a) or milligray per year (mGy/a); pottery moisture content, %;
groundwater fluctuation factor;
β annual dose of moist samples, in units of The annual dose of β for dry samples is in Gy/a or mGy/a; the annual dose for wet samples is in Gy/a or mGy/a; the annual dose for dry samples is in Gy/a or mGy/a; the soil moisture content at the site where the pottery was unearthed is %.
5.5 Thermoluminescent dosimeter (TLD) measures the environmental dose rate at archaeological sites (8)
. (10)
Bury the thermoluminescent dosimeter within a radius of 30 cm from the site where the pottery sample was unearthed. The burial time is 3 months to 1 year to measure the radioactive dose in the environment. See Appendix D. Calibration of laboratory radioactive sources
6.1 β source (9Sr/9Y)
6.1.1 β source in thermoluminescent instrument
It is usually a round metal plate source. Sr has a half-life of 28 years and a maximum energy of only 0.54MeV. Its daughter \Y has a half-life of 64h and a maximum energy of 2.26MeV.
6.1.2 Calibration with dose
Irradiate the thermoluminescent dose element with a source of known radioactive dose to calibrate the β source and transfer the Y dose to the β source. 6.1.3 Calibration with a calibrated natural uranium block
Irradiate the thermoluminescent dose element with a natural uranium block of known radioactive dose to calibrate the β source and obtain the irradiation dose rate of this β source. 6.2α source (241Am or 244Cm)
6.2.1α source in thermoluminescence instrument
α sources used in thermoluminescence dating of ancient ceramics mainly use 241Am and 24*Cm. 6.2.2α source calibration
Use CaSO4:Tm ultra-thin thermoluminescent dose element to calibrate an α source with known intensity S to another α source with unknown intensity. Intensity S is the total track length density per unit time when α particles pass through quartz, unit: um-2/minGB/T37909—2019
Error in thermoluminescence dating of ancient ceramics
The calculation method of thermoluminescence dating error is shown in Appendix E. 8
Data processing and reporting
Sampling registration
Pottery and porcelain samples should be registered on their own forms after sampling. For the specific format, please refer to Appendix F Dating Record
When thermoluminescence dating of pottery, the pottery thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix G.
When thermoluminescence dating of porcelain, the porcelain thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix H.
3 Age determination report
Thermoluminescence age determination report, see Appendix 1 for the specific format. 8
A.1 Overview
Appendix A
(Normative Appendix)
Method for measuring ancient dose of pottery using fine particle technology GB/T37909—2019
The fine particle technology selects particles with a diameter of 3um~8μm that naturally exist in the sample as samples for measuring ancient dose. It mainly considers the range of α particles in pottery. The range of α particles in pottery is 15μm~50μm. Only particles with a diameter of less than 10μm can be completely penetrated by α rays, and the dose received is not significantly attenuated. A.2 Sample preparation
Acetone flotation method
A.2.1.1 Use tools to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for use. Avoid heating the sample during crushing and avoid violent impact on the sample. A.2.1.2 Take 400mg of fine particle sample and put it into a 150mL beaker, and use acetone flotation. A.2.1.3 Use a beaker, add acetone to a height of 60mm, shake the beaker and put it into an ultrasonic bath for several minutes. After the beaker is left to stand for 2min, pour the suspension into another beaker, and let it stand for another 20min. Pour out the suspension, and the particles left in the beaker are the fine particle samples needed for dating.
A.2.1.4 Take 30 flat-bottomed test tubes with a diameter of 11mm, and put a 9.5mm diameter stainless steel disc or aluminum disc (hereinafter referred to as disc) in each test tube. In the beaker containing the fine particle sample, pour acetone to suspend the fine particles evenly. Use a burette to take an equal amount of the suspension and inject it into the test tube containing the disc
A.2.1.5 Stand 30 test tubes upright on a test tube rack and put them in a drying oven at 50°C. After the fine particles are completely precipitated on the disc, use a siphon to suck out most of the acetone, and then let the acetone evaporate naturally in the drying oven. After drying, the disc sample is taken out of the test tube. Prepare a disc sample by precipitation in each test tube. Prepare the number of samples according to the measurement needs. A.2.2 Water flotation method
A.2.2.1 Use a tool to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for standby use. Avoid heating the sample during crushing and avoid the sample from receiving severe impact. A.2.2.2 Place 400 mg of sample in a 150 mL beaker and use distilled water for flotation. A.2.2.3 Add distilled water to a height of 70 mm. After stirring, let the beaker stand for 10 minutes. At this time, particles with a diameter greater than 8 μm have settled to the bottom of the beaker, and particles with a diameter less than 8 μm are suspended. A.2.2.4 Slowly pour the suspension in this beaker into another 150 mL beaker and let it stand for 60 minutes. After 60 minutes, the particles still suspended are all less than 3 μm in diameter.
A.2.2.5 Pour out the suspension with particles less than 3 μm. What remains in the beaker is a fine particle sample of 3 μm to 8 μm. The suspension and sedimentation times of 10 minutes and 60 minutes, respectively, are approximate values calculated based on Stokes formula (A.1). 9nh
2(pp）gr
Wherein:
S—suspension and sedimentation time, in seconds (s); n—viscosity coefficient of water at 20°C, in Pascal seconds (Pa·s); (Al)3 Calibration with a calibrated natural uranium block
Use a natural uranium block with a known radioactive dose to irradiate the thermoluminescent dose element to calibrate the β source and obtain the irradiation dose rate of this β source. 6.2 α source (241Am or 244Cm)
6.2.1 α source in thermoluminescent instrument
The α source used in thermoluminescent dating of ancient ceramics mainly uses 241Am and 24*Cm. 6.2.2 α source calibration
Use the CaSO4:Tm ultra-thin thermoluminescent dose element to calibrate an α source with a known intensity S to another α source of unknown intensity. The intensity S is the total track length density per unit time when the α particles pass through quartz, unit: um-2/minGB/T37909—2019
Error in thermoluminescent dating of ancient ceramics
The calculation method of thermoluminescent dating error is shown in Appendix E. 8
Data processing and reporting
Sampling registration
Pottery and porcelain samples should be registered on their own forms after sampling. For the specific format, please refer to Appendix F Dating Record
When thermoluminescence dating of pottery, the pottery thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix G.
When thermoluminescence dating of porcelain, the porcelain thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix H.
3 Age determination report
Thermoluminescence age determination report, see Appendix 1 for the specific format. 8
A.1 Overview
Appendix A
(Normative Appendix)
Method for measuring ancient dose of pottery using fine particle technology GB/T37909—2019
The fine particle technology selects particles with a diameter of 3um~8μm that naturally exist in the sample as samples for measuring ancient dose. It mainly considers the range of α particles in pottery. The range of α particles in pottery is 15μm~50μm. Only particles with a diameter of less than 10μm can be completely penetrated by α rays, and the dose received is not significantly attenuated. A.2 Sample preparation
Acetone flotation method
A.2.1.1 Use tools to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for use. Avoid heating the sample during crushing and avoid violent impact on the sample. A.2.1.2 Take 400mg of fine particle sample and put it into a 150mL beaker, and use acetone flotation. A.2.1.3 Use a beaker, add acetone to a height of 60mm, shake the beaker and put it into an ultrasonic bath for several minutes. After the beaker is left to stand for 2min, pour the suspension into another beaker, and let it stand for another 20min. Pour out the suspension, and the particles left in the beaker are the fine particle samples needed for dating.
A.2.1.4 Take 30 flat-bottomed test tubes with a diameter of 11mm, and put a 9.5mm diameter stainless steel disc or aluminum disc (hereinafter referred to as disc) in each test tube. In the beaker containing the fine particle sample, pour acetone to suspend the fine particles evenly. Use a burette to take an equal amount of the suspension and inject it into the test tube containing the disc
A.2.1.5 Stand 30 test tubes upright on a test tube rack and put them in a drying oven at 50°C. After the fine particles are completely precipitated on the disc, use a siphon to suck out most of the acetone, and then let the acetone evaporate naturally in the drying oven. After drying, the disc sample is taken out of the test tube. Prepare a disc sample by precipitation in each test tube. Prepare the number of samples according to the measurement needs. A.2.2 Water flotation method
A.2.2.1 Use a tool to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for standby use. Avoid heating the sample during crushing and avoid the sample from receiving severe impact. A.2.2.2 Place 400 mg of sample in a 150 mL beaker and use distilled water for flotation. A.2.2.3 Add distilled water to a height of 70 mm. After stirring, let the beaker stand for 10 minutes. At this time, particles with a diameter greater than 8 μm have settled to the bottom of the beaker, and particles with a diameter less than 8 μm are suspended. A.2.2.4 Slowly pour the suspension in this beaker into another 150 mL beaker and let it stand for 60 minutes. After 60 minutes, the particles still suspended are all less than 3 μm in diameter.
A.2.2.5 Pour out the suspension with particles less than 3 μm. What remains in the beaker is a fine particle sample of 3 μm to 8 μm. The suspension and sedimentation times of 10 minutes and 60 minutes, respectively, are approximate values calculated based on Stokes formula (A.1). 9nh
2(pp）gr
Wherein:
S—suspension and sedimentation time, in seconds (s); n—viscosity coefficient of water at 20°C, in Pascal seconds (Pa·s); (Al)3 Calibration with a calibrated natural uranium block
Use a natural uranium block with a known radioactive dose to irradiate the thermoluminescent dose element to calibrate the β source and obtain the irradiation dose rate of this β source. 6.2 α source (241Am or 244Cm)
6.2.1 α source in thermoluminescent instrument
The α source used in thermoluminescent dating of ancient ceramics mainly uses 241Am and 24*Cm. 6.2.2 α source calibration
Use the CaSO4:Tm ultra-thin thermoluminescent dose element to calibrate an α source with a known intensity S to another α source of unknown intensity. The intensity S is the total track length density per unit time when the α particles pass through quartz, unit: um-2/minGB/T37909—2019
Error in thermoluminescent dating of ancient ceramics
The calculation method of thermoluminescent dating error is shown in Appendix E. 8
Data processing and reporting
Sampling registration
Pottery and porcelain samples should be registered on their own forms after sampling. For the specific format, please refer to Appendix F Dating Record
When thermoluminescence dating of pottery, the pottery thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix G.
When thermoluminescence dating of porcelain, the porcelain thermoluminescence dating record form should be filled in to record the data of each step of measurement. For the specific format, please refer to Appendix H.
3 Age determination report
Thermoluminescence age determination report, see Appendix 1 for the specific format. 8
A.1 Overview
Appendix A
(Normative Appendix)
Method for measuring ancient dose of pottery using fine particle technology GB/T37909—2019
The fine particle technology selects particles with a diameter of 3um~8μm that naturally exist in the sample as samples for measuring ancient dose. It mainly considers the range of α particles in pottery. The range of α particles in pottery is 15μm~50μm. Only particles with a diameter of less than 10μm can be completely penetrated by α rays, and the dose received is not significantly attenuated. A.2 Sample preparation
Acetone flotation method
A.2.1.1 Use tools to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for use. Avoid heating the sample during crushing and avoid violent impact on the sample. A.2.1.2 Take 400mg of fine particle sample and put it into a 150mL beaker, and use acetone flotation. A.2.1.3 Use a beaker, add acetone to a height of 60mm, shake the beaker and put it into an ultrasonic bath for several minutes. After the beaker is left to stand for 2min, pour the suspension into another beaker, and let it stand for another 20min. Pour out the suspension, and the particles left in the beaker are the fine particle samples needed for dating.
A.2.1.4 Take 30 flat-bottomed test tubes with a diameter of 11mm, and put a 9.5mm diameter stainless steel disc or aluminum disc (hereinafter referred to as disc) in each test tube. In the beaker containing the fine particle sample, pour acetone to suspend the fine particles evenly. Use a burette to take an equal amount of the suspension and inject it into the test tube containing the disc
A.2.1.5 Stand 30 test tubes upright on a test tube rack and put them in a drying oven at 50°C. After the fine particles are completely precipitated on the disc, use a siphon to suck out most of the acetone, and then let the acetone evaporate naturally in the drying oven. After drying, the disc sample is taken out of the test tube. Prepare a disc sample by precipitation in each test tube. Prepare the number of samples according to the measurement needs. A.2.2 Water flotation method
A.2.2.1 Use a tool to crush the pottery sample, and use a 60μm (250 mesh) sampler to screen out particles with a diameter of less than 60μm for standby use. Avoid heating the sample during crushing and avoid the sample from receiving severe impact. A.2.2.2 Place 400 mg of sample in a 150 mL beaker and use distilled water for flotation. A.2.2.3 Add distilled water to a height of 70 mm. After stirring, let the beaker stand for 10 minutes. At this time, particles with a diameter greater than 8 μm have settled to the bottom of the beaker, and particles with a diameter less than 8 μm are suspended. A.2.2.4 Slowly pour the suspension in this beaker into another 150 mL beaker and let it stand for 60 minutes. After 60 minutes, the particles still suspended are all less than 3 μm in diameter.
A.2.2.5 Pour out the suspension with particles less than 3 μm. What remains in the beaker is a fine particle sample of 3 μm to 8 μm. The suspension and sedimentation times of 10 minutes and 60 minutes, respectively, are approximate values calculated based on Stokes formula (A.1). 9nh
2(pp）gr
Wherein:
S—suspension and sedimentation time, in seconds (s); n—viscosity coefficient of water at 20°C, in Pascal seconds (Pa·s); (Al)4 Slowly pour the suspension in this beaker into another 150mL beaker and let it stand for 60 minutes. After 60 minutes, the particles still suspended are smaller than 3um in diameter.
A.2.2.5 Pour out the suspension with particles smaller than 3um. What is left in the beaker is a fine particle sample of 3pm to 8μm. The suspension and sedimentation times of 10min and 60min respectively are approximate values calculated according to Stokes formula (A.1). 9nh
2(pp）gr
Where:
S—suspension and sedimentation time, in seconds (s); n—viscosity coefficient of water at 20℃, in Pascal seconds (Pa·s); (Al)4 Slowly pour the suspension in this beaker into another 150mL beaker and let it stand for 60 minutes. After 60 minutes, the particles still suspended are smaller than 3um in diameter.
A.2.2.5 Pour out the suspension with particles smaller than 3um. What is left in the beaker is a fine particle sample of 3pm to 8μm. The suspension and sedimentation times of 10min and 60min respectively are approximate values calculated according to Stokes formula (A.1). 9nh
2(pp）gr
Where:
S—suspension and sedimentation time, in seconds (s); n—viscosity coefficient of water at 20℃, in Pascal seconds (Pa·s); (Al)
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