The early Precambrian odyssey of the North China Craton: A synoptic overview

Precambrian geology of China

Lithotectonic elements of Precambrian basement in the North China Craton: Review and tectonic implications

Growth and reworking of the early Precambrian continental crust in the North China Craton: Constraints from zircon Hf isotopes

Zircon U-Pb and Hf isotopic constraints on the Early Archean crustal evolution in Anshan of the North China Craton

Crustal growth in the North China Craton at 2.5Ga: Evidence from in situ zircon U-Pb ages, Hf isotopes and whole-rock geochemistry of the Dengfeng complex

Widely distributed on the southern margin of the North China Craton, the Taihua complex extends roughly in an east-west direction and the relatively complete successions are found in Lushan County, Henan Province. Like many other Archean terranes, the Taihua Complex can be divided into two major lithological units along the Dangze River, namely gneisses series and supracrustal rocks. The former is located on the north side of the river and chiefly composed of TTG gneisses and amphibolites; the latter on the south side of the river is mainly supracrustal rock. Coupled with the previous studies, the results obtained by this study show that the Taihua complex was formed in a large time span from Neoarchean to Palaeoproterozoic. The TTG gneisses and amphibolites are dated at Neoarchean (2794–2752 Ma). The 2.9 Ga and 3.1 Ga zircons in amphibolites could be xenocrysts. In the North China Craton, the 2.8–2.7 Ga old rocks crop out in several areas e.g. western Shandong Province, Jiaodong Peninsula and Lushan area of Henan Province. In addition, 2.8–2.7 Ga detrital zircons or xenocryst zircons have been recognized in Huai’an, Fuping, Wutai areas of North China Craton and also reported in the Early Paleozoic diamondiferous kimberlites in Mengyin and Fuxian. All these age results indicate that the 2.8–2.7 Ga rocks may have been developed much broader region than today’s outcrops. Zircon Hf and whole rock Nd isotopes show that the 2.8–2.7 Ga tectono-thermal event represents an important period of crustal growth with minor ancient crust reworked in the North China Craton. However the formation of supracrustal rocks is limited to 2.2–2.0 Ga in the Palaeoproterozoic time, not the Archaean, as previously believed. Combined with the chronological data of aluminium-rich metamorphic rocks (Khondalite series) on the southern margin of the North China Craton and adjacent areas, it is suggested that the above areas have widely developed Paleoproterozoic passive continental margin environment.

LA-(MC)-ICPMS U-Pb zircon geochronology and Lu-Hf isotope compositions of the Taihua complex on the southern margin of the North China Craton

In situ U-Pb dating and Lu-Hf isotopic analysis were carried out for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southern margin of the North China Craton (NCC). The results provide further constraints on the crustal formation and evolution history of NCC. Four 207Pb/206Pb age populations were obtained from 99 analyses, with clusters at ∼3.40 Ga, 2.77–2.80 Ga, ∼2.50 Ga and 2.34 Ga, respectively. The 3.40 Ga old zircons have similar Hf isotopic compositions to those from Archean rocks in the Jidong and Anshan areas of NCC. However, crustal remnants older than 3.6 Ga have been identified in the southern margin of NCC, the South China Craton, the northwestern part of the Qinling Orogen and its adjacent area. Thus, it is not easy to trace the source rock from which the 3.40 Ga detrital zircons were derived. It can be inferred that the crustal remnants older than 3.40 Ga might have been widely distributed in the North China Craton. The 2.77–2.80 Ga zircons make up a relatively small proportion and have the highest eHf (t) values (up to 6.1±1.6), consistent with the Hf isotopic composition of the depleted mantle at 2.83 Ga. Their single-stage Hf model age of 2.83 Ga is close to their crystallized age, suggesting that their source rocks were extracted from the contemporaneous depleted mantle. The ∼2.50 Ga zircon grains constitute about 85% of the total grain population and their Hf isotopic compositions indicate major growth of juvenile crust at ∼2.50 Ga but minor reworking of ancient crust. The youngest zircon dated in this study gave an U-Pb age of 2337±23 Ma, which can be considered the maximum depositional age of the formation of the Songshan Group.

U-Pb ages and Hf isotopes for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southwestern margin of the North China Craton

New evidence for ~4.45Ga terrestrial crust from zircon xenocrysts in Ordovician ignimbrite in the North Qinling Orogenic Belt, China

High-precision U-Pb dating by in situ LA-ICP-MS yields an age of 4079±5 Ma for a xenocrystal zircon from Ordovician volcanics of the Caotangou Group in western part of the North Qinling Orogenic Belt As a result, the North Qinling Orogenic Belt becomes one of a few localities in the world that contain Hadean age records (4276±6 Ma and 4404±8 Ma detrital zircons from Jack Hill of the Yilgarn craton, 4016 Ma Acasta gneisses of the Wopmay Orogeny and Burang quartzite with detrital zircon of 4103 Ma in Tibet) It is also the first report of the Hadean age in Phanerozoic volcanics The finding of the 41 Ga xenocrystal zircon provides not only the geochronological record of the oldest crustal materials in China, but also the condition for further search for rocks forming in the region during the early time of the Earth’s evolution Thirty-six zircon U-Pb dates from the Ordovician volcanic rocks are subgrouped into seven generations that represent different tectono-magmatic events in the North Qinling Orogenic Belt Among them, two periods of 09–15 Ga and 04–05 Ga are consistent with Mesoproterozoic and Early Paleozoic orogenies, respectively

Hongliang Wang

Papers

Crustal growth in the North China Craton at 2.5Ga: Evidence from in situ zircon U-Pb ages, Hf isotopes and whole-rock geochemistry of the Dengfeng complex

LA-(MC)-ICPMS U-Pb zircon geochronology and Lu-Hf isotope compositions of the Taihua complex on the southern margin of the North China Craton

U-Pb ages and Hf isotopes for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southwestern margin of the North China Craton

New evidence for ~4.45Ga terrestrial crust from zircon xenocrysts in Ordovician ignimbrite in the North Qinling Orogenic Belt, China

4.1 Ga xenocrystal zircon from Ordovician volcanic rocks in western part of North Qinling Orogenic Belt