Neoarchean Dengfeng forearc and accretionary complexes, North China craton Geological Society of America Bulletin, v. 1XX, no. XX/XX 1 Structural relationships and kinematics of the Neoarchean Dengfeng forearc and accretionary complexes, southern North China craton Bo Huang 1 , Timothy Kusky 1,2,3,† , Lu Wang 1 , Ali Polat 1,4 , Dong Fu 1 , Brian Windley 1,5 , Hao Deng 1 , and Junpeng Wang 1 1 State Key Laboratory of Geological Processes and Mineral Resources, Center for Global Tectonics, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China 2 Three Gorges Research Center for Geo-hazards, China University of Geosciences, Wuhan 430074, China 3 Department of Geological Engineering, Middle East Technical University, TR-06531 Ankara, Turkey 4 Department of Earth and Environmental Sciences, University of Windsor, Windsor, Ontario N9B 3P4, Canada 5 Department of Geology, University of Leicester, Leicester LE1 7RH, UK GSA Bulletin; Month/Month 2018; v. 130; no. X/X; p. 000–000; https://doi.org/10.1130/B31938.1; 15 figures; Data Repository item 2018294. † Corresponding author: tkusky@gmail.com. ABSTRACT The ca. 2.54–2.51 Ga Dengfeng greenstone belt in the southern section of the Central orogenic belt of the North China craton con- sists of structurally juxtaposed slices of meta- ultramafic, metamafic, and felsic igneous rocks, metasedimentary rocks, including mi- nor banded iron formation. The complex was metamorphosed to greenschist to amphibolite facies at ca. 2.5 Ga and intruded by ca. 2.50– 2.42 Ga mafic and felsic plutons/dikes. Detailed field mapping and structural analyses show that the different lithostructural units, in- cluding a metamafic-dominant unit and a metasedimentary-dominant unit, are in tec- tonic contact, with complex thrust imbrication and multiple brittle and ductile deformation. The metasedimentary-dominant unit con- sists of coherent schist-metabasalt sequences, metaturbidites, and chaotic mélanges that are characterized by typical duplex structures and block-in-matrix fabrics, closely resem- bling the lithostratigraphy and structural patterns of Phanerozoic accretionary com- plexes. Together with distinctive and diag- nostic geochemical signatures of metabasalts, sanukitoid-like metadiorite, and syntectonic adakitic sills/dikes, we interpret the Dengfeng greenstone belt as Neoarchean forearc and accretionary complexes consisting of dismem- bered forearc crustal sheets in the west and accreted oceanic plate stratigraphy in the east that were structurally imbricated at a conver- gent plate margin. The kinematic indicators and the spatial configurations of different tec- tonic units suggest a near-southwest-dipping intra-oceanic subduction zone beneath the arc in the Central orogenic belt, which later evolved into an arc-continent collision with the Eastern block. The accreted arc and accretionary prism are unconformably over- lain by a clastic sedimentary wedge, the lower part of which has a maximum depositional age of ca. 2.45 Ga and is interpreted as a fore- land basin sequence related to this collision. Documentation of the Neoarchean Dengfeng forearc and accretionary complexes demon- strates that ca. 2.5 Ga intra-oceanic subduc- tion, oceanic plate stratigraphy accretion, and arc-continent collisional events occurred in the southern section of the Central orogenic belt of the North China craton. The accretion of the 2.54–2.51 Ga arc to the continental margin of the Eastern block marks an early episode of mountain building in the Central orogenic belt, which played an important role in the lat- eral growth of the North China craton. INTRODUCTION Archean granite-greenstone belts generally consist of spatially and temporally related, in- trusive and extrusive, metamorphosed ultramafic and mafic to felsic magmatic rocks, commonly associated with variable amounts and types of metasedimentary rocks, and intruded by gran- itoid plutons (Condie, 1981, 1997; Windley, 1976, 1993, 1995; de Wit and Ashwal, 1997; Kusky, 1993, 2004; Furnes et al., 2015). Many models have been proposed to explain the ori- gin and tectonic setting of various greenstone belts, amongst which the more popular are (1) continental rifting (e.g., Goodwin, 1981; Zhang et al., 1985), (2) convergent plate bound- aries, including back-arc, forearc, and/or mar- ginal basins (Kusky, 1989; Taira et al., 1992; Windley, 1995; Komiya et al., 1999; Kusky and Polat, 1999; Polat et al., 2005, 2016; Arai et al., 2015), (3) mantle plume or arc-plume/craton- plume interaction (Campbell et al., 1989; Ker- rich et al., 1998; Polat et al., 2006), (4) oceanic crust/ophiolites (de Wit et al., 1987; de Wit, 2004; Kusky et al., 2001; Kusky, 2004; Furnes et al., 2015; Grosch and Slama, 2017), and (5) synclinal basins between open granitoid domes (e.g., Van Kranendonk et al., 2004; Brown, 2015). The geodynamic processes and driving mechanisms responsible for the generation of Archean greenstone belts and associated gran- itoids also include contrasting opinions, such as: (1) subduction-collision–related processes by some form of plate tectonics (e.g., de Wit et al., 1987; de Wit, 2004; Kusky, 1993; Kimura et al., 1993; Komiya et al., 1999; Kusky et al., 2013; Polat et al., 1998, 2006, 2015, 2016), and (2) nonsubduction vertical-dominant tectonics (e.g., plume, diapirism, and “sagduction”; e.g., Van Kranendonk et al., 2004; Brown, 2015; Johnson et al., 2016). These debates lead to on- going controversaries surrounding the transition timing from nonsubduction tectonic regimes to Phanerozoic-style plate tectonics (Komiya et al., 1999; Brown and Johnson, 2018). However, for many Precambrian greenstone belts, different lithotectonic fragments with different origins are tectonically juxtaposed and mixed (e.g., Kusky and Vearncombe, 1997; Polat and Kerrich, 1999; de Wit et al., 2018). To adequately address their tectonic origin and evolution, comprehensive lithologic, structural, and metamorphic inves- tigations based on detailed field observations combined with precise geochemical and geo- chronological data are necessary (Kusky, 1991; For permission to copy, contact editing@geosociety.org © 2018 Geological Society of America