Paleoproterozoic Granitoids on Liaodong Peninsula, North China Craton  

作　　者：ZHU Kai LIU Zhenghong XU Zhongyuan LIU Jiexun WANG Xing’an 

机构地区：[1]College of Geo-exploration Science and Technology,Jilin University,Changchun 130061,China [2]College of Earth Sciences,Jilin University,Changchun 130061,China [3]College of Geographical Sciences,Northeast Normal University,Changchun 130024,China

出　　处：《Acta Geologica Sinica(English Edition)》2019年第5期1377-1396,共20页地质学报（英文版）

基　　金：financially supported by the 3D Geological Mapping and Deep Geological Survey of the China Geological Survey under a pilot project entitled Deep Geological Survey of the Benxi–Linjiang Area (Project No. 1212011220247)

摘　　要：Paleoproterozoic granitoids are an important constituent of the Jiao-Liao-Ji Belt(JLJB). The spatial-temporal distribution and types of Paleoproterozoic granitoids are closely related to the evolution of the JLJB. In this paper, we review the field occurrence, petrography, geochronology, and geochemistry of Paleoproterozoic granitoids on Liaodong Peninsula, northeast China. The Paleoproterozoic granitoids can be divided into pre-tectonic(~2.15 Ga;peak age=2.18 Ga) and post-tectonic(~1.85 Ga) granitoids. The pre-tectonic granitoids are magnetite and hornblende-biotite monzogranites and granodiorites. Pre-tectonic monzogranites are widespread in the JLJB and have A2-type affinities. In contrast, pretectonic granodiorites are only present in the Simenzi area and have adakitic affinities. The post-tectonic granitoids consist of porphyritic monzogranite, syenite, diorite, granodiorite, quartz monzonite, monzogranite, and granitic pegmatite, which are adakitic rocks and I-, S-, and A2-type granitoids. The assemblage of pre-tectonic A2-type granitoids and adakitic rocks indicates the initial tectonic setting of the JLJB was a continental back-arc basin. The assemblage of post-tectonic adakitic rocks and I-, S-, and A2-type granitoids indicates a post-collisional setting. The 2.20-2.15 Ga A2-type granitoids and adakitic rocks were associated with the initial stage of back-arc extension, and the peak of back-arc extension is inferred from the subsequent(2.15-2.10 Ga) mafic intrusive activity. The ~1.90 Ga adakitic rocks mark the beginning of the postcollisional stage, which was followed by the intrusion of low-temperature S-and I-type granitoids. High-to low-pressure granitoids(S-type) were generated during the peak of post-collisional lithospheric delamination and asthenospheric upwelling. The emplacement of later granitic pegmatites occurred during the waning of the orogeny.Paleoproterozoic granitoids are an important constituent of the Jiao–Liao–Ji Belt（JLJB）. The spatial-temporal distribution and types of Paleoproterozoic granitoids are closely related to the evolution of the JLJB. In this paper, we review the field occurrence, petrography, geochronology, and geochemistry of Paleoproterozoic granitoids on Liaodong Peninsula, northeast China. The Paleoproterozoic granitoids can be divided into pre-tectonic（～2.15 Ga; peak age=2.18 Ga） and post-tectonic（～1.85 Ga） granitoids. The pre-tectonic granitoids are magnetite and hornblende–biotite monzogranites and granodiorites. Pre-tectonic monzogranites are widespread in the JLJB and have A2-type affinities. In contrast, pretectonic granodiorites are only present in the Simenzi area and have adakitic affinities. The post-tectonic granitoids consist of porphyritic monzogranite, syenite, diorite, granodiorite, quartz monzonite, monzogranite, and granitic pegmatite, which are adakitic rocks and I-, S-, and A2-type granitoids. The assemblage of pre-tectonic A2-type granitoids and adakitic rocks indicates the initial tectonic setting of the JLJB was a continental back-arc basin. The assemblage of post-tectonic adakitic rocks and I-, S-, and A2-type granitoids indicates a post-collisional setting. The 2.20–2.15 Ga A2-type granitoids and adakitic rocks were associated with the initial stage of back-arc extension, and the peak of back-arc extension is inferred from the subsequent（2.15–2.10 Ga） mafic intrusive activity. The ～1.90 Ga adakitic rocks mark the beginning of the postcollisional stage, which was followed by the intrusion of low-temperature S-and I-type granitoids. High-to low-pressure granitoids（S-type） were generated during the peak of post-collisional lithospheric delamination and asthenospheric upwelling. The emplacement of later granitic pegmatites occurred during the waning of the orogeny.

关 键 词：Paleoproterozoic granitoids pre-tectonic granitoids post-tectonic granitoids POST-COLLISION continental backarc basin Jiao–Liao–Ji Belt 

分 类 号：P58[天文地球—岩石学]