scholarly journals Fluid Inclusions and C-H-O-S-Pb Isotope Systematics of the Changfagou Deposit, Jilin Province, Northeast China

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-21 ◽  
Author(s):  
Bo Peng ◽  
Bile Li ◽  
Jun Chen
Keyword(s):  
Partial Melting ◽  
North China Craton ◽  
Lower Crust ◽  
North China ◽  
Tectonic Setting ◽  
Ore Deposits ◽  
Jilin Province ◽  
Magmatic Fluid ◽  
Northern Margin ◽  
The North

The Changfagou Cu deposit in Jilin province, China, is located in the eastern segment of the northern margin of the North China Craton and lies at the southern end of the Lesser Xing’an Mountains-Zhanggangcailing Mountains. According to the mineral paragenetic association and its various relationships, the hydrothermal mineralization can be divided into 4 metallogenic stages from early to late: stage I is K-feldspar-quartz-magnetite, stage II is quartz-molybdenite, stage III is quartz-chalcopyrite (polymetallic sulfide), and stage IV is carbonate. Stages II and III are the main metallogenic stages. Overall, the metallogenic fluid associated with the Changfagou deposit is characterized as a F-rich CO2-H2O-NaCl hydrothermal system. The hydrogen and oxygen isotopic characteristics suggest the initial ore-forming fluids of the Changfagou deposit evolved from a primitive magmatic fluid and mixed with meteoric water. The sulfur and lead isotopic characteristics show that the metallogenic material was derived from partial melting of the lower crust. Phase separation or immiscibility is the important mechanism in the precipitation of molybdenum, whereas a decrease in temperature is the important mechanism in the precipitation of copper polymetallic sulfides. The above characteristics are similar to those of the porphyry deposits related to continental environments. Compared with the deposits in the Xilamulun metallogenic belt, both have similar metallogenic ages and tectonic positions. In conclusion, the Changfagou deposit formed in an intracontinental extensional environment due to lithospheric thinning. The mineralization was related to magmatism associated with partial melting of the lower crust. The intersection of the Dunhua-Mishan fracture and Kangbao-Chifeng fracture along the northern margin of the North China Craton is a promising location for porphyry ore deposits related to a continental tectonic setting.

Comparative studies on two phases of Archaean TTG magmas from different blocks of the North China Craton: petrogenesis and constraints on crustal evolution

2020 ◽  
pp. 1-16
Author(s):  
Houxiang Shan ◽  
Mingguo Zhai ◽  
RN Mitchell ◽  
Fu Liu ◽  
Jinghui Guo
Keyword(s):  
North China Craton ◽  
Lower Crust ◽  
North China ◽  
Tectonic Setting ◽  
Source Material ◽  
Crustal Growth ◽  
Garnet Amphibolite ◽  
The North ◽  
Western Block ◽  
Subducting Slab

Abstract Whole-rock major and trace elements and Hf isotopes of magmatic zircons of tonalite–trondhjemite–granodiorite (TTG) rocks with different ages (2.9, 2.7 and 2.5 Ga) from the three blocks (the Eastern Block, Western Block and Trans-North China Orogen) of the North China Craton were compiled to investigate their respective petrogenesis, tectonic setting and implications for crustal growth and evolution. Geochemical features of the 2.5 Ga TTGs of the Eastern Block require melting of predominant rutile-bearing eclogite and subordinate garnet-amphibolite at higher pressure, while the source material of the 2.7 Ga TTGs is garnet-amphibolite or granulite at lower pressure. The 2.5 Ga TTGs have high Mg#, Cr and Ni, negative Nb–Ta anomalies and a juvenile basaltic crustal source, indicating derivation from the melting of a subducting slab. In contrast, features of the 2.7 Ga TTGs suggest generation from melting of thickened lower crust. The 2.5 and 2.7 Ga TTGs in the Trans-North China Orogen were formed at garnet-amphibolite to eclogite facies, and the source material of the 2.5 Ga TTGs in the Western Block is most likely garnet-amphibolite or eclogite. The 2.5 Ga TTGs in the Trans-North China Orogen and Western Block were generated by the melting of a subducting slab, whereas the 2.7 Ga TTGs in the Trans-North China Orogen derived from melting of thickened lower crust. The Hf isotopic data suggest both the 2.5 and 2.7 Ga TTG magmas were involved with contemporary crustal growth and reworking. The two-stage model age (TDM2) histograms show major crustal growth between 2.9 and 2.7 Ga for the whole North China Craton.

scholarly journals Early Permian Granitic Magmatism in Middle Part of the Northern Margin of the North China Craton: Petrogenesis, Source, and Tectonic Setting

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 99
Author(s):  
Longxue Li ◽  
Qingye Hou ◽  
Dingling Huang ◽  
Xinyu Wang
Keyword(s):  
North China Craton ◽  
North China ◽  
Magma Mixing ◽  
Tectonic Setting ◽  
Middle Part ◽  
Early Permian ◽  
Northern Margin ◽  
Inductively Coupled ◽  
The North ◽  
Type Granite

The late Palaeozoic was an important period of tectonic evolution for the northern margin of the North China Craton (NCC). The source(s) and tectonic setting of early Permian granitoid rocks emplaced along the northern margin of the NCC are still unclear. These granitoids formed between ~295.4–276.1 Ma (uncertainties ranging from ±1.5 to ±7.8 Ma) according to zircon laser ablation inductively coupled mass spectrometry (LA-ICP-MS) and sensitive high-resolution ion microprobe (SHRIMP) U-Pb data. The Dadongou (DDG) pluton is an A1-type granite and the Dananfangzi (DNFZ) pluton is an A2-type granite. The Erdaowa (EDW), Lisicun (LSC), Wuhai (WH) and Gehuasitai (GHST) plutons are I-type granites. The Yuanbaoshan (YBS) dykes are diorite and syenodiorite. All the granitoids are enriched in large ion lithophile elements and light rare earth elements, depleted in high field strength elements and have negative εNd(t) and εHf(t) values. The A1-type granite was formed by the melting of the mafic crust. The A2-type granite was derived from partial melting of tonalite gneiss from the NCC crust and mantle materials. The EDW, LSC, WH and GHST granites mainly originated from partially melted granulite, with some mantle input. The YBS dykes are formed by the magma mixing of hot mantle melt and the relatively cold crustal magma. The northern margin of the NCC experienced anorogenic and collision tectonic stages, and the structural setting started to transform to post-collision at the later period of early Permian.

In-situ reaction-replacement origin of hornblendites in the Early Cretaceous Laiyuan complex, North China Craton, and implications for its tectono-magmatic evolution

2021 ◽  
Author(s):  
Jia Chang ◽  
Andreas Audétat ◽  
Jian-Wei Li
Keyword(s):  
Partial Melting ◽  
North China Craton ◽  
Lithospheric Mantle ◽  
Lower Crust ◽  
North China ◽  
Ultramafic Rocks ◽  
Magmatic Evolution ◽  
Mafic Magmas ◽  
Felsic Rocks

Abstract Two suites of amphibole-rich mafic‒ultramafic rocks associated with the voluminous intermediate to felsic rocks in the Early Cretaceous Laiyuan intrusive-volcanic complex (North China Craton) are studied here by detailed petrography, mineral- and melt inclusion chemistry, and thermobarometry to demonstrate an in-situ reaction-replacement origin of the hornblendites. Moreover, a large set of compiled and newly obtained geochronological and whole-rock elemental and Sr-Nd isotopic data are used to constrain the tectono-magmatic evolution of the Laiyuan complex. Early mafic‒ultramafic rocks occur mainly as amphibole-rich mafic‒ultramafic intrusions situated at the edge of the Laiyuan complex. These intrusions comprise complex lithologies of olivine-, pyroxene- and phlogopite-bearing hornblendites and various types of gabbroic rocks, which largely formed by in-situ crystallization of hydrous mafic magmas that experienced gravitational settling of early-crystallized olivine and clinopyroxene at low pressures of 0.10‒0.20 GPa (∼4‒8 km crustal depth); the hornblendites formed in cumulate zones by cooling-driven crystallization of 55‒75 vol% hornblende, 10‒20 vol% orthopyroxene and 3‒10 vol% phlogopite at the expense of olivine and clinopyroxene. A later suite of mafic rocks occurs as mafic lamprophyre dikes throughout the Laiyuan complex. These dikes occasionally contain some pure hornblendite xenoliths, which formed by reaction-replacement of clinopyroxene at high pressures of up to 0.97‒1.25 GPa (∼37‒47 km crustal depth). Mass balance calculations suggest that the olivine-, pyroxene- and phlogopite-bearing hornblendites in the early mafic‒ultramafic intrusions formed almost without melt extraction, whereas the pure hornblendites brought up by lamprophyre dikes required extraction of ≥ 20‒30 wt% residual andesitic to dacitic melts. The latter suggests that fractionation of amphibole in the middle to lower crust through the formation of reaction-replacement hornblendites is a viable way to produce adakite-like magmas. New age constraints suggest that the early mafic-ultramafic intrusions formed during ∼132‒138 Ma, which overlaps with the timespan of ∼126‒145 Ma recorded by the much more voluminous intermediate to felsic rocks of the Laiyuan complex. By contrast, the late mafic and intermediate lamprophyre dikes were emplaced during ∼110‒125 Ma. Therefore, the voluminous early magmatism in the Laiyuan complex was likely triggered by the retreat of the flat-subducting Paleo-Pacific slab, whereas the minor later, mafic to intermediate magmas may have formed in response to further slab sinking-induced mantle thermal perturbations. Whole-rock geochemical data suggest that the early mafic magmas formed by partial melting of subduction-related metasomatized lithospheric mantle, and that the early intermediate to felsic magmas with adakite-like signatures formed from mafic magmas through strong amphibole fractionation without plagioclase in the lower crust. The late mafic magmas seem to be derived from a slightly different metasomatized lithospheric mantle by lower degrees of partial melting.

Gold deposits of the northern margin of the North China Craton: multiple late Paleozoic–Mesozoic mineralizing events

2002 ◽  
Vol 37 (3) ◽  
pp. 326-351 ◽  
Author(s):  
Craig J. Hart ◽  
Richard J. Goldfarb ◽  
Yumin Qiu ◽  
Lawrence Snee ◽  
Lance D. Miller ◽  
...  
Keyword(s):  
North China Craton ◽  
North China ◽  
Gold Deposits ◽  
Late Paleozoic ◽  
Northern Margin ◽  
The North
Sign in / Sign up

Export Citation Format

Share Document