Geochronology, geochemistry and tectonic significance of a Paleoproterozoic diabase at southwestern margin of the NCC

The diabase and granite porphyry outcrop in the Baijiagou section within the Meso-Cenozoic Liupanshan fault zone at the southwestern margin of the North China Craton (NCC), and they have been regarded previously as Meso-Cenozoic dykes according to their occurrence. Zircon U-Pb LA-ICP-MS age determining for the diabase and granite porphyry yield respectively 1804 ± 21 and 1792 ± 16 Ma, and they form a bimodal magmatic assemblage of Paleoproterozoic. The diabase can be classified into two major geochemical types, which are low-Ti (LT) and high-Ti (HT) in nature. The former is characterized by relatively high SiO2 (48.81 54.01 wt.%), P2O5, and Al2O3, and low TiO2 (1.41 1.54 wt.%), FeO, MnO, and CaO, and enriched whole-rock Sr and Nd isotopic composition [(Sr/Sr)i = 0.703 0.708; εNd= -3.76 to -4.37]. The latter has lower SiO2 (45.9 51.19 wt.%), P2O5, and Al2O3, and higher TiO2 (1.61 2.26 wt.%) and FeO than that of the former, and depleted Sr and Nd isotopic composition [(Sr/Sr)i = 0.691 0.708; εNd = 3.27 5.03]. Both types of diabase exhibit light rare earth element enrichment and flat middle-heavy rare earth element patterns. The LT diabase has negative Eu anomalies and higher total REE contents than the HT diabase. Th/Nb ratios of the LT and HT diabases are 0.28 0.29 and 0.08 0.10, respectively, which are similar to basalts formed in an intraplate spreading setting in association with a mantle plume. The regional geology suggests that intracontinental rifting occurred at the southwestern margin of the NCC in the Paleoproterozoic, and that the rifting was related to a mantle plume. This rifting event was part of the break-up of the Columbia supercontinent. Article history: Received 18 July 2018 Revised 21 April 2019 Accepted 27 May 2019

[1]  T. Zhao,et al.  Genetic relationship between 1780 Ma dykes and coeval volcanics in the Lvliang area, North China , 2017, Precambrian Research.

[2]  You-liang Ji.  Paleoproterozoic Granite Porphyry in Southwestern Margin of North China Craton and its Geological Significance , 2014 .

[3]  Zhai Minggu.  Meso-Neoproterozoic magmatic events and multi-stage rifting in the NCC , 2014 .

[4]  M. Santosh,et al.  Metallogeny of the North China Craton: Link with secular changes in the evolving Earth , 2013 .

[5]  G. Shan.  Formation epoch and its geological implications of Paleoprotozoic A-ype granite in Shizuizi of Jingyuan County,Ningxia Province , 2013 .

[6]  Huaichun Wu,et al.  Pre-Rodinia supercontinent Nuna shaping up: A global synthesis with new paleomagnetic results from North China , 2012 .

[7]  Yigang Xu,et al.  Destruction of the North China Craton , 2012, Science China Earth Sciences.

[8]  M. Zhai,et al.  Nature and origin of the Wenquan granite: Implications for the provenance of Proterozoic A-type granites in the North China craton , 2011 .

[9]  M. Santosh,et al.  The early Precambrian odyssey of the North China Craton: A synoptic overview , 2011 .

[10]  Qiu-li Li,et al.  Neoproterozoic (~ 900 Ma) Sariwon sills in North Korea: Geochronology, geochemistry and implications for the evolution of the south-eastern margin of the North China Craton , 2011 .

[11]  Dong Chun.  Late Palaeoproterozoic crustal evolution of the North China Craton and formation time of the Jingshan Group: Constraints from SHRIMP U-Pb zircon dating of meta-intermediate-basic intrusive rocks in eastern Shandong Province , 2011 .

[12]  Shuangquan Zhang,et al.  ̃2.7Ga crust growth in the North China craton , 2010 .

[13]  Cui Min.  Zircon/baddeleyite U-Pb dating for the Paleo-proterozoic intermediate-acid intrusive rocks in Xiaoshan Mountains,west of Henan Province and their constraints on the age of the Xiong'er Volcanic Province , 2010 .

[14]  Geng Yuan.  Late Neoarchean to Early Paleoproterozoic magmatic events and tectonothermal systems in the North China Craton , 2010 .

[15]  Hu Guo.  Geochemistry and tectonic setting of the 1.78 Ga mafic dyke swarms in the Mt.Zhongtiao and Mt.Song areas,the southern margin of the North China Craton , 2010 .

[16]  Li Cheng.  Revisiting the new classification of granitic rocks based on whole-rock Sr and Yb contents:Index , 2010 .

[17]  T. Zhao,et al.  Geochemical and Nd–Hf isotopic constraints on the origin of the ~ 1.74-Ga Damiao anorthosite complex, North China Craton , 2009 .

[18]  Mei Zhou,et al.  Geochemical constraints on the tectonic setting of Paleoproterozoic A-type granites in the southern margin of the North China Craton , 2009 .

[19]  G. Lister,et al.  Configuration of the Late Paleoproterozoic Supercontinent Columbia: Insights from radiating mafic dyke swarms , 2008 .

[20]  M. Zhai,et al.  A 1.78 Ga large igneous province in the North China craton: The Xiong'er volcanic province and the North China dyke Swarm , 2008 .

[21]  T. Kusky,et al.  Nature of mantle source contributions and crystal differentiation in the petrogenesis of the 1.78 Ga mafic dykes in the central North China craton , 2007 .

[22]  Yue Zhao,et al.  The 1.75–1.68 Ga anorthosite-mangerite-alkali granitoid-rapakivi granite suite from the northern North China Craton: Magmatism related to a Paleoproterozoic orogen , 2007 .

[23]  Zhai Mingguo.  Petrogenesis and Tectonic Setting of the Paleoproterozoic Xiong'er Group in the Southern Part of the North China Craton:a Review , 2007 .

[24]  Y. Luo,et al.  Geochemical characteristics and geological significance of the Paleoproterozoic volcanic rocks from the Xiaoliangling Formation in the Lüliang area,Shanxi Province. , 2007 .

[25]  Z. Ming.  Paleoproterozoic events in the North China Craton. , 2007 .

[26]  M. Zhai,et al.  Geochronological Constraints on the Paleoproterozoic Evolution of the North China Craton: SHRIMP Zircon Ages of Different Types of Mafic Dikes , 2005 .

[27]  Detlef Günther,et al.  Solid sample analysis using laser ablation inductively coupled plasma mass spectrometry , 2005 .

[28]  S. Wilde,et al.  Late Archean to Paleoproterozoic evolution of the North China Craton: key issues revisited , 2005 .

[29]  P. Peng,et al.  Geochemistry and geological significance of the 1.8 Ga mafic dyke swarms in the North China Craton: an example from the juncture of Shanxi, Hebei and Inner Mongolia , 2004 .

[30]  Wan Yu-sheng,et al.  Post-Orogenic Granites with an Age of 1800 Ma in Luliang Area, North China Craton: Constraints from Isotopic Geochronology and Geochemistry , 2004 .

[31]  C. Miller,et al.  Hot and cold granites? Implications of zircon saturation temperatures and preservation of inheritance , 2003 .

[32]  Zhang Cheng-jiang.  Discrimination of the Tectonic Settings of Basalts by Th, Nb and Zr , 2003 .

[33]  D. Rubatto.  Zircon trace element geochemistry: partitioning with garnet and the link between U–Pb ages and metamorphism , 2002 .

[34]  L. Songnian,et al.  A Group of Rifting Events in the Terminal Paleoproterozoic in the North China Craton , 2002 .

[35]  A. Nutman,et al.  From source migmatites to plutons: tracking the origin of ca. 435 Ma S-type granites in the East Greenland Caledonian orogen , 2001 .

[36]  Wang Yun.  Th/Hf-Ta/Hf identification of tectonic setting of basalts. , 2001 .

[37]  Xu Yi.  The Emeishan Large Igneous Province: Evidence for mantle plume activity and melting conditions , 2001 .

[38]  R. Fu.  The Upper Chronological Limit of Xionger Group's Volcanic Rock Series, and its Geological Significance , 2000 .

[39]  K. Condie,et al.  Evolution of the Kaapvaal Craton as viewed from geochemical and SmNd isotopic analyses of intracratonic pelites , 1995 .

[40]  B. Weaver.  The origin of ocean island basalt end-member compositions: trace element and isotopic constraints , 1991 .

[41]  M. Meschede.  A method of discriminating between different types of mid-ocean ridge basalts and continental tholeiites with the Nb1bZr1bY diagram , 1986 .

[42]  W. Boynton.  Cosmochemistry of the rare earth elements: meteorite studies. , 1984 .

[43]  T. M. Harrison,et al.  Zircon saturation revisited: temperature and composition effects in a variety of crustal magma types , 1983 .

[44]  Julian A. Pearce,et al.  Trace element characteristics of lavas from destructive plate boundaries , 1982 .

[45]  T. Irvine,et al.  A Guide to the Chemical Classification of the Common Volcanic Rocks , 1971 .