Zircon U-Pb geochronology of the Chinese continental crust: a preliminary analysis of the Elsevier science database

Figures & data

Table 1. Description of the data categories listed under each item in our database.

Data item category	Index	Data item name	Data item interpretation
Data number	1(A)	Total number	It is the unique identification number of each piece of data, not repeated.
	2(B)	Sample test number	Sample number + test number
Element and isotope content	3(C)	total Pb	Total Pb content, in ppm
	4(D)	radiogenic Pb	Radiogenic lead content, in ppm
	5(E)	U	U content, in ppm
	6(F)	Th	Th content, in ppm
	7(G)	Th/U	Th/U ratio
Isotope ratio and error	9(I)	^206Pb/^238U	^206Pb/^238U ratio (atomic ratio)
	10(J)	σ	1σ absolute error of ^206Pb/^238U ratio
	11(K)	^207Pb/^235U	^207Pb/^235U ratio (atomic ratio)
	12(L)	σ	1σ absolute error of ^207Pb/^235U ratio
	13(M)	^207Pb/^206Pb	^207Pb/^206Pb ratio (atomic ratio)
	14(N)	σ	1σ absolute error of ^207Pb/^206Pb ratio
	15(O)	^208Pb/^232Th	^208Pb/^232Th ratio (atomic ratio)
	16(P)	σ	1σ absolute error of ^208Pb/^232Th ratio
Age and error	17(Q)	^206Pb/^238U	^206Pb/^238U age in Ma
	18(R)	σ	1σ absolute error of ^206Pb/^238U age in Ma
	19(S)	^207Pb/^235U	^207Pb/^235U age in Ma
	20(T)	σ	1σ absolute error of ^207Pb/^235U age in Ma
	21(U)	^207Pb/^206Pb	^207Pb/^206Pb age in Ma
	22(V)	σ	1σ absolute error of ^207Pb/^206Pb age in Ma
	23(W)	^208Pb/^232Th	^208Pb/^232Th age in Ma
	24(X)	σ	1σ absolute error of ^208Pb/^232Th age in Ma
Experimental technology background	25(Y)	Method	Test method for zircon U-Pb chronology: LA-ICP-MS, SHRIMP, SIMS, TIMS, etc.
	26(Z)	Standard	Zircon U-Pb standards, used for correction of U content and isotopic fractionation, such as SL13, CZ3, TEM, 91,500, M257, etc.
	27(AA)	Remarks	Additional information for supplemental experiments For example, standards for calibrating trace element content, etc.
Sample Background	28(AB)	Longitude	Longitude of the sampling location
	29(AC)	Latitude	Latitude of the sampling location
	30(AD)	Altitude	Altitude of the sampling location, part of the data are mine depths.
	31(AE)	Location	Sampling places’ names, by administrative area or by geological unit.
	32(AF)	Lithology	Lithology of the rock containing zircons
Quality supervision	33(AG)	Document number	It is convenient for later inquiry by making data correspond to the entered document.
	34(AH)	Data-importer	The name of data-importer.
	35(AI)	Inspector	The name of data-cleaner.
	36(AJ)	Director	The name of director.
Supplements	37(AK)	General Remarks	Additional information.
	38(AL)	^206Pbc（%）	Ordinary ^206Pb as a percentage of total ^206Pb.
	39(AM)	^206Pb (ppm)	Total ^206Pb content.
	40(AN)	^206Pbc(ppm)	^206Pb content in common lead.
	41(AO)	^206Pb*(ppm)	Radiogenic ^206Pb content.

Note: LA-ICP-MS, Laser ablation inductively coupled plasma mass spectrometer; SHRIMP, Sensitive high-resolution ion microprobe; SIMS, Secondary ion mass spectrometer; TIMS, thermal ionization mass spectrometer; Ma, millions of years; ppm, parts per million; and 1σ, single standard deviation. The abbreviations are similar hereafter.

Table 2. Data fitting of age values and their absolute errors for various methods.

		Adj R-squared					All methods		LA		SHRIMP		SIMS
Dependent variable	Regression equation	All methods	LA	Parameter	SIMS	Parameter	value	1σ	value	1σ	value	1σ	value	1σ
Age (^206Pb/^238U)	y = a(1 – e^−bx)	98.08%	98.66%	95.43%	99.66%	a	85.97	3.46	43.21	0.58	−450.63	196.12	82.45	1.91
						b	1.59E-04	7.81E-06	3.61E-04	7.41E-06	−3.54E-05	1.48E-05	1.91E-04	5.38E-06
Age (^207Pb/^235U)	y = a(1 – e^−bx)	88.91%	89.69%	14.86%	88.89%	a	17.77	0.07	17.64	0.06	20.46	0.53	15.21	0.09
						b	2.27E-03	4.23E-05	2.38E-03	4.25E-05	9.34E-03	1.74E-03	1.98E-03	4.84E-05
Age (^207Pb/^206Pb)	y = a-bln(x + c)	93.55%	93.28%	92.17%	92.34%	a	196.98	2.39	181.75	1.90	290.18	4.83	130.64	1.87
						b	22.12	0.31	19.86	0.25	35.13	0.63	15.43	0.26
						c	23.15	4.24	9.36	2.49	16.04	6.06	−7.50	7.31E-05
Age (^208Pb/^232Th)	y = a(1 – e^−bx)	89.75%	90.69%	62.17%	17.86%	a	87.78	5.82	81.28	4.75	39.54	3.71	9.12	1.53
						b	2.80E-04	2.49E-05	2.98E-04	2.38E-05	1.59E-03	2.65E-04	2.07E-02	2.01E-02

Figure 1. Scatter plots of average absolute error for various methods: (a) All methods age(²⁰⁶Pb/²³⁸U); (b) All methods age (²⁰⁷Pb/²³⁵U); (c) All methods age (²⁰⁷Pb/²⁰⁶Pb); (d) All methods age(²⁰⁸Pb/²³²Th); (e) LA-ICP-MS Age(²⁰⁶Pb/²³⁸U); (f) LA-ICP-MS Age (²⁰⁷Pb/²³⁵U); (g) LA-ICP-MS Age (²⁰⁷Pb/²⁰⁶Pb); (h) LA-ICP-MS Age (²⁰⁸Pb/²³²Th); (i) SHRIMP Age (²⁰⁶Pb/²³⁸U); (j) SHRIMP Age (²⁰⁷Pb/²³⁵U); (k) SHRIMP Age (²⁰⁷Pb/²⁰⁶Pb); (l) SHRIMP Age (²⁰⁸Pb/²³²Th); (m) SIMS Age (²⁰⁶Pb/²³⁸U); (n) SIMS Age (²⁰⁷Pb/²³⁵U); (o) SIMS Age (²⁰⁷Pb/²⁰⁶Pb); (p) SIMS Age (²⁰⁸Pb/²³²Th). Fitted curves are shown in each plot.

Table 3. Recommended radiometric method for different age intervals.

Recommended Age Method	Age (^206Pb/^238U)	Age (^207Pb/^235U)	Age (^207Pb/^206Pb)
All methods	<1388.96Ma	1388.96Ma~3282.52Ma	>3282.52Ma
LA-ICP-MS	<1383.44Ma	1383.44Ma~3874.44Ma	>3874.44Ma
SHRIMP	<1254.19Ma	1254.19Ma~2142.03Ma	>2142.03Ma
SIMS	<853.96Ma	853.96Ma~1832.76Ma	>1832.76Ma

Figure 2. Comparison of fitted curves for different radiometric ages: (a) all methods; (b) LA-ICP-MS; (c) SHRIMP; (d) SIMS.

Table 4. Appropriate age intervals of different U-Pb radiometric methods for dating.

Method	Age interval
LA-ICP-MS	<1002.73Ma
SHRIMP	1002.73Ma~ 3242.41 Ma
SIMS	> 3242.41Ma

Figure 3. Comparison of minimum standard error related to the recommended radiometric age for different measurement methods.

Figure 4. Age frequency histogram and Gaussian multi-peak fitting curves showing seven main peaks for all continental Chinese U-Pb geochronology data in the Elsevier science database (peak at 835.95Ma is not decomposed in this case).

Table 5. Gaussian multi-peak fitting results of the age frequency histograms for all Chinese U-Pb geochronology data.

	geological history^a		geological history^b		Cenozoic
Peak	value	1s^c	value	1s^c	value	1s^c
Peak1	48.60	4.32	48.71	4.08	16.55	0.42
Peak2	131.49	0.72	131.49	0.69	27.74	0.35
Peak3	249.91	1.70	249.97	1.60	35.24	0.21
Peak4	444.27	1.35	444.13	1.27	42.7	0.78
Peak5	835.95	4.41	813.01	3.10	51.61	0.30
Peak6	1860.65	5.49	869.62	11.48	61.47	0.65
Peak7	2505.54	3.56	1861.75	5.60	-	-
Peak8	-	-	2505.23	3.39	-	-
Adj^d R-squared	91.67%		92.58%		83.91%

^apeak at 835.95 Ma is not decomposed in this case;

^bpeak at 835.95 Ma is decomposed into two superimposed peaks in this case;

^c“s” represents the standard error of fitting result of each peak value

^dAdj. R-squared is the adjusted root-mean square error.

Figure 5. Age frequency histogram and Gaussian multi-peak fitting curves showing eight main peaks for all continental Chinese U-Pb geochronology data in the Elsevier science database (peak at 835.95Ma is decomposed into two superimposed peaks in this case).

Figure 6. Age frequency histogram and Gaussian multi-peak fitting curves for all continental Chinese Cenozoic Pb-U geochronology data in the Elsevier science database.

Figure 7. Regional distribution of 95.45% confidence intervals for zircon peak growth ages, representing various high-frequency peaks in age. (a) 48.60 Ma;(b) 131.49 Ma;(c) 249.91 Ma;(d) 444.27 Ma; (e) 835.95 Ma; (f) 1860.65 Ma; (g) 2505.54 Ma.

Figure 8. Regional distribution of 95.45% confidence intervals for zircon peak growth ages within the Cenozoic era, representing high-frequency peaks for ages: (a) 16.55 Ma; (b) 27.74 Ma; (c) 35.24 Ma; (d) 42.70 Ma; (e) 51.61 Ma; (f) 61.47 Ma.

Data availability statement

The data referred to in this paper is not publicly available at the current time.