Hadean zircon
Occurrence
Occurrences Analytic method and result Interpretation

Hadean zircon

Section Title: Occurrence
Table Section Text: Occurrences Analytic method and result Interpretation

Occurrences	Analytic method and result	Interpretation

Australia[edit]

Mt. Narryer	Ion microprobe dating of 80 detrital zircons from quartzites have disclosed that 2% to 12% grains >4.0Ga, with younger zircons ranging to ca.3 Ga.	Diversity of source rock. Magmatic origins.

Churla Wells	The grains are 4.14 to 4.18Ga by using 207Pb/206Pb dating. Core region has a much lower Hf, REE, Uand Th than other outer region.	Granitic magma origin

Maynard Hills	Dating of greenstone belt revealed that the 207Pb/206Pb age is 4.35Ga.	/

Mt Alfred	The concordant zircon has the age 4.17Ga. No geochemistry data has been collected	/

North America[edit]

Northwest Territory, Canada	The protolith crystallisation age is 3.96Ga analysed by U-Pb dating. Applying LA-ICP-MS, 4.20+0.06Ga zircon was being dated.	Magmatic origin. Derivation from a felsic melt by a process other than differentiation of a mafic magma

Greenland	The crystallisation age is determined as 3.83±0.01Ga by ion microprobe dating. 4.08±0.02Ga was identified in U-Pb survey	/

Asia[edit]

Tibet	In ion microprobe method, detrital grain's Th/U ratios is greater than 0.7	Magmatic origin

North Qinling	The LA-ICP-MS age of xenocrystic zircon in North Qinling Orogenic Belt is 4.08Ga. Hf isotope also support the age data of LA-ICP-MS test	/

North China Craton	The zircon is 4.17±0.05Ga determined by LA-ICP-MS U-Pb dating method. Th/U ratio is 0.46	Magmatic origin

South China	Conducting ion microprobe U-Pb dating, 207Pb/206Pb age is 4.13±0.01 Ga with 5.9±0.1% 18O isotope data. Positive Ce anomaly	early earth is a highly oxidizing environment and a high Ti-in-zircons crystallization temperature of 910'C.

South America[edit]

Southern Guyana	4.22Ga by LA-ICP-MS U-Pb dating method. No other geochemical analysis has been conducted	/

Eastern Brazil	The age of the rock is 4.22Ga and Th/U ratios of 0.8 and high U contents (up to 1400ppm)	Felsic magmatic origin

Sentence(s)

In North China Craton The Hadean zircon is 4.17±0.05Ga determined by LA-ICP-MS U-Pb dating method.

final_sentence: In North China Craton The Hadean zircon is 4.17±0.05Ga determined by LA-ICP-MS U-Pb dating method.