Changes in orogenic style and surface environment recorded in Paleoproterozoic foreland successions

Domain: earth_science
Published: 2023-12-02
Editorial outcome: major_revision

Abstract
The Earth’s interior and surficial systems underwent dramatic changes during the Paleoproterozoic, but the interaction between them remains poorly understood. Rocks deposited in orogenic foreland basins retain a record of the near surface to deep crustal processes that operated during subduction to collision and provide information on the interaction between plate tectonics and surface responses through time. Here, we document the depositional-to-deformational lifecycle of a Paleoproterozoic foreland succession from the North China Craton. The succession was deposited in a foreland basin following ca. 2.50–2.47 Ga Altaid-style arc–microcontinent collision, and then converted to a fold-and-thrust belt at ca. 2.0–1.8 Ga due to Himalayan-style continent–continent collision. These two periods correspond to the assembly of supercratons in the late Archean and of the Paleoproterozoic supercontinent Columbia, respectively, which suggests that similar basins may have been common at the periphery of other cratons. The multiple stages of orogenesis and accompanying tectonic denudation and silicate weathering, as recorded by orogenic foreland basins, likely contributed to substantial changes in the hydrosphere, atmosphere, and biosphere known to have occurred during the Paleoproterozoic.

Introduction
Earth is the only known planet that has emergent felsic continents and currently operates in a plate tectonic (mobile lid) mode. It is also the only place known to be (or have been) inhabited, where its habitability is sustained through interactions between the lithosphere, hydrosphere, atmosphere, and biosphere1–4. The late Archaean to early Paleoproterozoic was one of the most transformative periods in Earth’s history5–7 (Fig. 1), witnessing the widespread emergence of continents above sea level, global cratonisation, the onset of the supercontinent cycle and, perhaps, the establishment of global plate tectonics8–10. In terms of near-surface processes, this period is associated with the formation of large-scale banded- and granular-iron formations (BIF and GIF) and graphite–phosphorite mineralisation, the Huronian glaciation, the Great Oxidation Event (GOE), and the emergence of multicellular life (eukaryotes)11–14 (Fig. 1c). Although there is a growing consensus that (global) plate tectonics was operative in the late Archaean to early Paleoproterozoic10,15–17, whether and how the orogenic style might have differed from modern subduction-to-collision systems and the feedback mechanisms between solid and surficial reservoirs are not well understood.

The erosion, transportation and deposition of clastic sediments during tectonic uplift and weathering of continental rocks likely mediated the long-term carbon cycle in deep time18–20. Foreland basins form between fold-and-thrust belts and the craton interior in typical orogens, representing an important sedimentary archive of the processes associated with continent–continent or arc–continent collision at convergent plate boundaries21. These successions characterise the source-to-sink history of detritus produced during the uplift and unroofing of orogenic crust22, and thus have the potential to chart any changes in orogenic style and attendant near-surface processes.

Here, we document a well-preserved early Paleoproterozoic foreland succession (the Songshan Group) in the North China Craton. The succession was deposited in a foreland basin related to a ca. 2.5–2.47 Ga Altaid-style arc–microcontinent collision, and later converted to a fold-and-thrust belt during ca. 2.0–1.8 Ga Himalayan-style collisional orogenesis. Integrating geochronology and structural datasets, we provide constraints on the distinct style of orogenesis and plate tectonics that characterised the Neoarchean and Paleoproterozoic. We then link the processes of mountain building, crustal uplift, denudation-sedimentation, and silicate weathering to dramatic changes in the hydrosphere, atmosphere, and biosphere during the Paleoproterozoic.

Results
Geological background
The North China Craton has been subdivided into the Eastern and Western blocks, separated and margined by several Neoarchean to Paleoproterozoic orogenic belts that record its incorporation into the Columbia supercontinent (Fig. 2a, b)23–26. The major north–south trending orogenic belt in the central North China Craton, variably termed the Neoarchean Central Orogenic Belt24 or the Paleoproterozoic Trans-North China Orogen27, marks the assembly of the Western and Eastern blocks and intervening arcs (Supplementary Note).

In the southern segment of the central orogen, the Songshan Group is a well-exposed Paleoproterozoic sedimentary succession considered to have formed within a foreland basin24,28, although details regarding its provenance and time of deposition and deformation remain incompletely constrained. It unconformably overlies Neoarchean TTG gneisses and metavolcano-sedimentary (greenstone) assemblages of the Dengfeng (-Angou) Complex, and is unconformably overlain by the unmetamorphosed Paleo- to Mesoproterozoic sedimentary succession of the lower Wufoshan Group (Fig. 2c)28–30. The Dengfeng Complex is interpreted to comprise a subduction-related arc/forearc unit in the west, and an ocean plate stratigraphy-dominated accretionary unit in the central part16,29,31, which together are interpreted to represent a Neoarchean paired metamorphic belt, and to record seafloor spreading, oceanic subduction, to an arc–microcontinent collision event32. A metasedimentary and gneissic unit in the eastern Dengfeng Complex is regarded as a passive margin sequence with cratonic basement16,29. The greenstone assemblage of the central Dengfeng Complex is strongly deformed, with minor small-scale tight-isoclinal folds formed during top-to-the-NE/E thrusting29. Available U–Pb isotopic dating of metamorphic zircon and titanite has identified a ca. 2.5 Ga episode of amphibolite facies metamorphism31,32, although the influence of the Paleoproterozoic events on the rocks is poorly constrained.

The Songshan Group mainly comprises metamorphosed submarine siliciclastic and chemical sedimentary sequences33,34. The group has been regarded as a ca. 2.5–2.3 Ga peripheral foreland basin sequence unconformably overlying both the Central Orogenic Belt and the Eastern Block, which was formed by the collision between an arc that lay to the west of the Eastern Block24,25,29. In this model, the foreland basin probably evolved to become a retro-arc foreland or rift basin in the middle-late Paleoproterozoic, during which time the upper part of the group was deposited25,29. An alternative model considers the entire Songshan Group to represent a significantly younger (maximum depositional ages of 2.35 Ga in the lower section and 1.96–1.78 Ga in the upper section) retro-arc foreland basin that developed behind an Andean-type continental arc along the western margin of the Eastern Block, then was incorporated into the Paleoproterozoic (ca. 1.97–1.85 Ga) Trans-North China orogen during collision between the Western and Eastern blocks of the North China Craton27,28.

We undertook detailed structural analysis and collected samples from the Songshan Group, the underlying Dengfeng Complex, and the overlying Wufoshan Group, for petrological and multi-mineral geochronological analysis (zircon/rutile U–Pb and amphibole/white mica 40Ar/39Ar dating). These new data constrain the depositional-to-deformational evolution of the Songshan foreland basin. Furthermore, analysis of detrital and/or metamorphic zircon and rutile identifies distinct metamorphic patterns within the detrital source regions, thereby providing additional insight into the styles of orogenesis and plate tectonics operating during the Neoarchean to Paleoproterozoic.

Field characteristics and petrology
The Songshan Group is a N–S-striking sequence of metasedimentary rocks that is up to ~1.7 km thick and comprises basal conglomerate, quartzite, quartz-mica schist, with minor layers of marble and GIF (Fig. 2c, d). The strata are strongly deformed, underwent upper greenschist (locally up to amphibolite) facies metamorphism and were intruded by mafic and felsic dikes/plutons and other igneous bodies33. The Songshan Group has been subdivided into four lithological packages termed, from stratigraphic base to top, the Luohandong, Wuzhiling, Miaopo, and Huayu formations33 (Fig. 2c; Supplementary Fig. 1).

The Luohandong Formation is dominated by a thick (100s of metres) sequence of quartzites (Supplementary Fig. 2a, b), with a 2–5-m thick basal conglomerate that overlies the Neoarchean quartz-mica schists and TTG gneisses of the Dengfeng Complex (Fig. 3). The clasts in the deformed conglomerate are preferentially aligned with the tectonic foliation and consist mainly of quartzite (some bearing magnetite), and quartz-mica schist (Fig. 3e, f). The quartzite is composed mainly of recrystallised quartz with minor muscovite (Supplementary Fig. 3c) and preserves ripple marks, flute casts and cross-bedding (Supplementary Fig. 2b), consistent with a nearshore littoral facies depositional environment.

The overlying Wuzhiling Formation is up to ~750 m thick and composed of quartz-mica schist and quartzite (Supplementary Fig. 2c) with minor marble and GIF interlayers (Supplementary Fig. 1). The quartz-mica schist consists of white mica, quartz, feldspar (mainly K-feldspar and albite), with minor biotite and rutile (Supplementary Fig. 3f, g). The protoliths are dominantly fine-grained siltstone, shale, quartz sandstone, and chemical sediments, which were likely deposited in littoral to neritic environments. The Wuzhiling Formation is intruded by a large diabase pluton with a zircon U–Pb age of ca. 2.32–2.30 Ga35,36 (Fig. 2c, d; Supplementary Fig. 4), which provides a minimum age for deposition of the lower Songshan Group strata. The Miaopo and Huayu formations that comprise the upper Songshan Group are dominated by white to purple banded quartzite and interbedded quartz-mica schist (Supplementary Fig. 2d), with minor layers of marble and phosphorite in the upper parts33.

The Wufoshan Group, which unconformably overlies both the Dengfeng Complex and Songshan Group, comprises a lower section (Ma’anshan Formation) of basal conglomerate, quartz sandstone, siltstone, and mudstone, with negligible metamorphism and deformation (Supplementary Fig. 2e–h). The sandstone is composed mainly of rounded detrital quartz grains that contain dust rims and quartz overgrowths (Supplementary Fig. 3i).

Structural style
The Songshan Group is strongly deformed, with numerous fold and thrust structures developed at outcrop to regional scales33. At a regional scale, N- to NE-striking gentle to tight isoclinal folds developed due to E–W to NW–SE-directed shortening (Fig. 2c, Supplementary Fig. 5a). Most tight isoclinal folds are overturned, and the axial planes mainly dip to the NW. The folding is stronger in the central and western domains (Luohandong and Wuzhiling formations). At the outcrop scale, tight, chevron, recumbent, commonly rootless folds, asymmetric boudinage, S–C fabrics and duplex structures are widely developed in the lower Songshan Group (Fig. 4; Supplementary Fig. 5b–d). Collectively, the asymmetric structures indicate top-to-the-SE or -NE thrusting and shear sense at middle-to-upper crustal levels (Figs. 2d, 4). The overall structural patterns of the Songshan Group are broadly similar to those of modern fold-and-thrust belts, such as in the Alpine orogen.

Detrital zircon U–Pb geochronology
To constrain the maximum depositional age, metamorphic age and provenance of the (meta)sedimentary rocks, we analysed zircon and/or rutile grains within samples of basal conglomerate, quartzite and quartz-mica schist from the Songshan Group, along with a quartz sandstone from the Ma’anshan Formation of the Wufoshan Group (Methods, Supplementary Data 1). Detailed results are presented in Supplementary Note, with U–Pb concordia diagrams and probability distribution diagrams shown in Supplementary Figs. 6 and 7, respectively.

Detrital zircons from the Luohandong and Wuzhiling formations of the Songshan Group have 207Pb/206Pb ages of 3.45–2.38 Ga (n=213), and 2.78–2.33 Ga (n=147), respectively. The Luohandong Formation samples contain three major zircon age populations at 3.45–3.35 Ga, 2.76–2.58 Ga, and 2.57–2.45 Ga, with a minor population at 2.44–2.38 Ga (Supplementary Fig. 7c). In contrast, the Wuzhiling Formation has a major age population at 2.56–2.45 Ga with a 2.51 Ga maximum, along with a subordinate older population at 2.77–2.57 Ga with a peak at 2.69 Ga (Supplementary Fig. 7g).

Detrital zircons in a quartz-mica schist sample from the upper Dengfeng Complex below the unconformity exhibit a single age peak at 2.56 Ga (Fig. 5a; Supplementary Fig. 7b). Detrital zircons in the quartz sandstone sample from the lower Wufoshan Group (Ma’anshan Formation) yield a span of ages from 2.9 to 1.79 Ga, with dominant age populations at 2.67, 2.56, 2.45, 2.34, 2.14, and 2.0–1.80 Ga (Supplementary Fig. 7k). Notably, some detrital zircon grains have core–rim structures, in which metamorphic rims have ages between 2.0–1.9 Ga except for two >2.1 Ga (Supplementary Fig. 8a). Some Paleoproterozoic zircons (ca. 2.1–1.8 Ga), with or without rims, have low Lu contents and (Lu/Dy)N ratios (Fig. 6), showing depletion in heavy rare earth elements (HREE) in chondrite-normalised diagrams (Supplementary Fig. 8c).

Rutile U–Pb geochronology
Rutile grains in the samples of quartzite and metaconglomerate from the lower Songshan Group are euhedral, subhedral, or irregular, and generally oriented (sub)parallel to the dominant foliation (Fig. 7a–c; Supplementary Fig. 6i–k). Analyses of rutile yield U–Pb ages of ca. 2.50 Ga (n=3), 2.31–2.05 Ga (n=11) and 2.00–1.75 Ga (n=62), with peaks at 1.95 Ga and 1.87 Ga (Fig. 5e). The pressure-independent Zr-in-rutile (ZIR) geothermometer indicates temperatures of 469–586°C (mean 505°C) for <2.0 Ga rutile grains (Fig. 7e, g), which are consistent with metamorphic temperatures obtained by the Ti-in-biotite geothermometer (Supplementary Note, Data 2 and Tables 2, 3).

In contrast, rutile grains from the unmetamorphosed quartz sandstone of the lower Wufoshan Group are well-rounded (Fig. 7d), consistent with a detrital origin. They have U–Pb ages of 2.5–2.0 Ga (n=6) and 1.98–1.75 Ga (n=54), with two populations clustering at 1.94 Ga and 1.83 Ga (Fig. 5g). Rutile grains from the lower Wufoshan Group yield higher ZIR temperatures of 577–876°C (except for one 479°C), with a mean of 740°C (Fig. 7f, g).

40Ar/39Ar geochronology
We obtained high-quality 40Ar/39Ar ages (Methods, Supplementary Data 3) for white mica and amphibole from metamorphic rocks of the central Dengfeng Complex known to record Neoarchean peak metamorphic ages and evidence for Paleoproterozoic overprinting32,37. Amphibole from the two different amphibolite samples yields 40Ar/39Ar plateau ages of 2035±6 Ma (MSWD=1.14, p=0.33) and 1861±4 Ma (MSWD=1.65, p=0.06) (Supplementary Fig. 9a, b). White mica grains from two garnet quartz-mica schist samples yield 40Ar/39Ar plateau ages of 1826±2 Ma (MSWD=0.45, p=0.92) and 1816±3 Ma (MSWD=1.7, p=0.16) (Supplementary Fig. 9c, d).

Depositional and metamorphic ages of the Songshan foreland succession
Due to the absence of dateable volcanogenic horizons, the depositional age of the Songshan Group is imprecisely known, and can only be bracketed by the youngest reliable age of detrital zircon (maximum depositional ages, MDA) and that of the oldest magmatic intrusion (minimum depositional ages). After considering different approaches (see refs. 38,39, Methods), we use the weighted mean ages of the youngest cluster that overlaps in age with 1σ uncertainty (YC1σ) as a conservative estimate of MDA (Supplementary Fig. 10 and Table S1).

Detrital zircons from the metamorphosed basal conglomerate of the lower Songshan Group yield a YC1σ age of 2465±22 Ma (n=5). The two quartzite samples from the Luohandong Formation yield YC1σ ages of 2429±19 Ma (n=4) and 2511±10 Ma (n=13). The quartzite and quartz-mica schist samples from the Wuzhiling Formation yield YC1σ ages of 2490±8 Ma (n=34) and 2507±6 Ma (n=35), respectively. These data, combined with zircon U–Pb ages of 2.32–2.30 Ga35,36 for mafic bodies intruded within the Wuzhiling Formation, constrain the depositional ages of the lowermost two formations of the Songshan Group to 2.47–2.32 Ga. A quartzite sample from the uppermost Songshan Group (Huayu Formation) yields a YC1σ age of 2241±20 Ma (n=4) and has a minimum depositional age of ca. 2.0–1.8 Ga based on the presence of metamorphic rutile (see below) that records post-depositional deformation. Detrital zircon and rutile from the Ma’anshan Formation of the lower Wufoshan Group yield YC1σ ages of 1813±11 Ma (n=13) and 1770±10 Ma (n=10), respectively, indicating an MDA of 1.77 Ga for the lowest Wufoshan Group.

The timing of metamorphism of the Songshan Group can be constrained by metamorphic rutile, which serves as a useful tool to date tectonothermal overprinting that is beyond the ability of zircon40. The young rutile grains (<2.0 Ga) from the Songshan Group are interpreted to be of metamorphic origin during post-depositional events based on the following lines of evidence: 1) the rutile grains exhibit a consistent alignment in the dominant foliation and have euhedral, subhedral and irregular shapes (Fig. 7a–c); 2) the peak ages of 1.95 Ga and 1.87 Ga are markedly younger than those of the detrital zircons (Fig. 5b–e); 3) the ZIR temperature of <2.0 Ga rutile grains is low (~469–586°C) and comparable with the Ti-in-biotite temperature (~558–598°C at 4 kbar) (Supplementary Tables 2–3); and 4) subordinate rutile grains with ages exceeding 2.0 Ga are inferred to have survived during prolonged Paleoproterozoic (at ca. 2.0–1.8 Ga) metamorphism, implying that the peak metamorphic temperature of the Songshan Group was lower than the closure temperature (~600°C) of rutile in the U–Pb isotope system41.

As the Songshan Group is unconformably overlain by the lower Wufoshan Group, cross-cut by 1.78-Ga post-kinematic granite, and contains metamorphic rutile, the timing of metamorphism and deformation of the Songshan Group is constrained at ca. 2.0–1.8 Ga. This is further substantiated by our samples from the underlying Dengfeng Complex in which a coeval Paleoproterozoic (ca. 2.03–1.82 Ga) tectono-thermal overprint is recognised based on amphibole and mica 40Ar/39Ar dating (Supplementary Fig. 9).

Sedimentary provenance in response to collisional orogenic events
Detrital zircon and rutile in sedimentary rocks provide key constraints on their igneous and/or metamorphic source regions, and hence the source-to-sink history22,40,42. In addition to our new data (n=745), we compiled published zircon U–Pb data from the Songshan and Wufoshan groups that include only analyses with <5% age discordance (Supplementary Data 4). All zircon (n=1364) and rutile (n=136) ages are plotted in Fig. 5.

All tectonic domains within the North China Craton have abundant 2.55–2.5 Ga basement rocks, but show differences in the proportions of older and younger rocks43 (Fig. 2b). The (Proto-) Eastern Block contains several old continental fragments, with zircon U–Pb ages of 3.8 Ga (Anshan, East Hebei, Xinyang), 3.4–3.2 Ga (Anshan), 3.0–2.9 Ga (East Hebei), 2.92–2.72 Ga (e.g., Lushan, West Shandong, Zanhuang)44,45. The Central Orogenic Belt contains minor 2.70–2.65 Ga and 2.4–1.9 Ga igneous rocks16,25,46, whereas the Western Block mainly comprises ca. 2.3–1.9 Ga igneous and sedimentary rocks (dominantly khondalite series, granitoids, and mafic intrusions)47. Notably, 1.95–1.80 Ga metamorphic events are widespread in the basement rocks of the North China Craton, notwithstanding several local exceptions that include the interior of the Eastern Block25,48,49.

Detritus within the lower section of the Songshan Group (Luohandong and Wuzhiling formations) contains diagnostic 3.4–3.2 Ga and 3.00–2.85 Ga zircon populations that are characteristics of the Eastern Block, whereas the dominant 2.7–2.5 Ga zircons were likely derived from both the Eastern Block and central orogen, as the Western Block was likely separated from these two domains in the early Paleoproterozoic26. Multiple lines of evidence, including Neoarchean (ca. 2.56–2.50 Ga) arc magmatism50, mélanges51,52, and paired metamorphism32, suggest that the Central Orogenic Belt represents a Neoarchean to earliest Paleoproterozoic accretionary-to-collisional orogen between intra-oceanic arc systems to the west and the Eastern Block to the east25. The arc(s) and frontal accretionary complexes were thrust upon continental margin sequences along the western margin of the Eastern Block16,51,53,54. The assembled orogenic wedge and continental block were unconformably overlapped by the lowest Songshan foreland basin sequences (<2.47 Ga), which received large volumes of detritus from the growing orogenic core and cratonic interior. The upper section of the Songshan Group records an increased contribution from 2.31–2.20 Ga detritus likely sourced from middle-Paleoproterozoic (mostly Rhyacian) magmatic rocks in the central orogen46.

The overlying lower Wufoshan Group contains magmatic zircon age populations at 2.52 Ga and 2.33–2.10 Ga, and with age peaks of magmatic and metamorphic zircons at 1.94 Ga and 1.82 Ga (Fig. 5f). The age peaks of detrital rutile at 1.94 Ga and 1.83 Ga (Fig. 5g) indicate that their sources underwent significant Paleoproterozoic (Orosirian) metamorphism. Collectively, our data are consistent with a detrital source dominated by thickened orogenic crust along the central orogen of the North China Craton where Paleoproterozoic (ca. 2.3–2.1 Ga) magmatic rocks are abundant46,55. The high-grade metamorphism recorded by detritus of rutile and metamorphic zircon (Supplementary Fig. 8) was related to the mid-Paleoproterozoic collisional orogenesis and cratonisation26.

Depositional-to-deformational evolution records two styles of orogenesis in North China
Our new data for the Songshan Group provide important constraints on Archaean to Paleoproterozoic orogenesis during the Precambrian evolution of the North China Craton (Fig. 8). The lowest Songshan Group (2.47–2.32 Ga) represents an early Paleoproterozoic foreland basin succession that unconformably overlapped the orogenic wedge and cratonic margin of the (Proto-) Eastern Block due to 2.5–2.47 Ga arc–microcontinent collision25, providing the key sedimentary evidence for terrane assembly and orogenesis at the end-Archaean to early Paleoproterozoic (Fig. 8a). Arc–microcontinent collision was likely followed by a reversal of subduction polarity56, leading to eastward subduction of oceanic lithosphere beneath the western margin of the Eastern Block that converted to an active continental margin. The upper Songshan Group (ca. 2.24–2.0 Ga) evolved into either a retro-arc foreland basin28, retro-arc extensional basin25, or mid-Paleoproterozoic (ca. 2.3–2.0 Ga) rifting/cratonic margin basin57 during the Paleoproterozoic, the details of which require further investigations. Nevertheless, the sedimentary basins and underlying Archaean basement of the North China Craton underwent strong modification (e.g., far-field effect) during late Paleoproterozoic (ca. 2.0–1.85 Ga) orogenesis, consistent with several Paleoproterozoic orogenic belts along its northern margin25,49 and the interior26,27,57,58.

The former Songshan foreland sequence was located in the front of the orogen, becoming a fold-and-thrust belt during the late Paleoproterozoic, as revealed by the strong compressional deformation and ages of metamorphic rutile (Fig. 8b). The underlying basement of the Dengfeng Complex records 40Ar/39Ar ages of 2.03–1.82 Ga (Supplementary Fig. 9), reflecting Paleoproterozoic tectono-thermal overprinting of the former Neoarchean orogenic wedge32. Thus, the Songshan Group records the life-cycle from an early peripheral foreland basin (ca. 2.47 Ga) to a retro-arc foreland basin, and finally to a fold-and-thrust belt (ca. 2.0–1.8 Ga), which was then unconformably overlapped by the younger foreland or intra-cratonic succession of the lower Wufoshan Group (<1.77 Ga) (Fig. 8c). These sedimentation-to-deformation processes were in response to two episodes of orogenesis in the North China Craton, and provide a partial record of the assembly of the Neoarchean supercratons59,60 (at ca. 2.5 Ga) and the amalgamation of the Paleoproterozoic Columbia supercontinent at 2.0–1.8 Ga9,61.

The majority of rutile in metamorphic rocks has been suggested to form under relatively high pressure62. Rutile preserved in sedimentary rocks can therefore be used to characterise any potential change in metamorphism of the detrital source. However, the possible preservation bias of rutile (e.g., Archaean) should be evaluated before interpreting the detrital rutile data set, as older rutile could be recrystallised or reset by younger higher-grade metamorphism due to its relatively low U–Pb closure temperature (~500–600°C)42. But our results, including textures, ages and Zr-in-rutile temperatures, provide compelling evidence that ca. 2.0–1.8 Ga rutile grains within the majority of the Songshan Group were neocrystallised during the Paleoproterozoic metamorphism rather than being recrystallised or reset from older Archaean detrital rutile grains. Although rutile from the Songshan and Wufoshan groups records similar U–Pb age patterns (Fig. 5e, g), it has different origins and metamorphic temperatures (Fig. 7e, f). Most rutile from the lower Songshan Group is of metamorphic origin (mean ZIR temperature=505°C) and records Orosirian ages (ca. 2.0–1.8 Ga, n=62) for post-depositional tectonothermal overprinting, with minor Neoarchean detrital rutiles (ca. 2.50 Ga, n=3) derived from the source regions (Fig. 7, Supplementary Table 2). In contrast, rutile from the overlying unmetamorphosed Wufoshan Group is of detrital origin, and records much higher-grade Paleoproterozoic metamorphism (mean ZIR temperature=740°C for 2.0–1.8 Ga rutile) in the source regions. Therefore, minor ca. 2.50 Ga detrital rutile grains in the lower Songshan Group that contrast with the abundant 2.0–1.8 Ga detrital rutile in the Wufoshan Group can be used to constrain the distinctive metamorphic characteristics during the Neoarchean and the Paleoproterozoic. Additionally, detrital zircon from the lower Wufoshan Group exhibits significant core–rim structures (~21%), with rims dominated by Paleoproterozoic ages (Supplementary Fig. 8a). Furthermore, some zircons have HREE-depleted signatures with low Lu contents and (Lu/Dy)N ratios (Fig. 6), implying they have a metamorphic garnet signature formed in a high-pressure (HP) setting63. These rutile and zircon provenance data together reflect two different metamorphic patterns: the first during the ca. 2.50–2.47 Ga arc–microcontinent collision and the second during Paleoproterozoic continent–continent collision, likely attributed to different orogenic styles.

In the late Neoarchean, small-scale arc–arc or arc–microcontinent ‘soft’ collisions led to the outward growth around existing cratonic nuclei16,25, forming large proto-cratonic continental landmasses (e.g., possible supercratons) (Fig. 8a). The style of such arc and/or microcontinent accretion and soft collision is analogous to Phanerozoic accretionary orogens, such as the Altaids (Central Asian Orogenic Belt), where most accretion and growth of Phanerozoic juvenile crust occurred64–66. Warm subduction with subsequent soft accretion-collision may be distinctive and characteristic of a warmer thermal state of the lithosphere and underlying mantle, which enabled intense slab melting and crustal growth16,67,68, but hindered the generation of abundant low-temperature–high-pressure metamorphic rocks in subduction-collision zones69. Consequently, rutile and HREE-depleted zircons are relatively rare in exhumed crustal metamorphic rocks, consistent with the detrital archive62,63 (Figs. 1a, 6, 7).

In the late Paleoproterozoic, the widespread occurrence of metamorphic rutile (Fig. 7g) and zircon (Supplementary Fig. 8a–c), as recorded by sedimentary rocks of the Wufoshan Group, indicate intense metamorphism at generally higher pressures. This is supported by the occurrence of high-pressure rocks (e.g., HP granulites, retrograde eclogites, low-T eclogite xenoliths70) in the North China Craton27,48,71, which is attributed to cold subduction and continent–continent collision during cratonisation of the North China Craton (Fig. 8b). The style (e.g., magmatism, metamorphism, sedimentation, scale and configuration) of Paleoproterozoic orogenies has been regarded as very similar to modern collisional orogenesis, such as the Himalayan orogen25,58,72. Furthermore, nearly all cratons record significant orogenic events at this time, which have been linked with the formation of the supercontinent Columbia (Fig. 2a)9,73. The lower Wufoshan Group that unconformably overlapped Archaean and early Paleoproterozoic basement in the North China Craton was likely deposited in a foreland or cratonic margin basin adjacent to a late Paleoproterozoic orogenic belt (Fig. 8c), receiving abundant detritus, including 2.0–1.8 Ga rutile and metamorphic zircon from the hinterland due to unroofing and erosion of the exhumed deep-level orogenic crust.

Linking orogenesis with the dramatic change in near-surface environments
The significant shift in orogenic styles as recorded by foreland basins in the North China Craton, albeit occurring at several times from the Neoarchean to the late Paleoproterozoic (ca. 2.7–1.8 Ga), is also observed in other cratons, including those in India, North America, Australia, and South Africa74–76. These changes likely had profound impacts on Earth’s near-surface environments, including the land, hydrosphere, atmosphere and biosphere1,16.

Late Archaean cratonisation was associated with Altaid-style arc–arc and/or arc–microcontinent accretion and soft collision, leading to the outward growth of continental crust and rapid emergence of subaerial landmasses5,16,25 (Fig. 9a). The exact elevation might have been comparable with modern arc–continent collisions, as in the Western Pacific accretionary systems. The emergent landmasses and increasing elevation enabled intense tectonic denudation and silicate weathering, resulting in an increase of nutrients (e.g., P, Mo) to the ocean and, consequently, the development of marine primary productivity and a concomitant increase in the level of atmospheric oxygen during the early Paleoproterozoic (2.45–2.1 Ga, Fig. 1c), known as the GOE7. Such change in weathering rates is recorded in seawater 87Sr/86Sr ratios, which increased rapidly from ca. 2.5 Ga and reached a peak at 2.3–2.2 Ga (Fig. 1b)77. Thick clastic (quartzite-dominated) units in the Songshan Group foreland sequences are consistent with emergent continental landmasses and high rates of weathering and erosion. The presence of GIF, carbonates, and purple quartzites and schists in the middle-upper parts of the succession indicate oxidative weathering35.

Detrital zircons from the lower Songshan Group were mainly derived from felsic sources, presumably dominated by TTG gneisses and volcanic rocks in greenstone belts. The dominance of mature (quartz-rich) sedimentary rocks require the dissolution of huge proportions of the feldspar and other silicate minerals, which must have consumed large volumes of CO219,78. The liberated Ca2+ and Mg2+ cations led to widespread deposition of marine carbonate rocks worldwide, which may have played an important role in carbon sequestration19. In addition, a lower rate of volcanism implied by the global magmatic slowdown (or ‘tectono-magmatic lull79’) at 2.4–2.2 Ga inhibited (eruptive) recycling of CO2 back into the atmosphere. The imbalance between the source and sink of carbon induced by these tectonic and sedimentary processes likely caused the decrease in atmospheric CO2 and 2.4–2.1 Ga icehouse conditions (Huronian glaciation)11 (Fig. 1c).

At ca. 2.2–2.0 Ga, carbon- and phosphorus-rich sediments such as graphite-bearing schists and phosphorites appear widely in the North China Craton (Fig. 1d) and other cratons55,80, consistent with the high marine primary productivity and increased burial of organic carbon as evidenced by a large positive δ13C excursion (the Lomagundi event, Fig. 1b). These changes have been linked to partial contributions from the Orosirian large igneous provinces and continental weathering following supercraton rifting55. The enhanced rates of weathering, along with thawing of the snowball Earth, would have provided more sediments to the trenches, which would have lubricated subduction zones1,81 and promoted cold and deeper subduction between ca. 2.1–1.9 Ga, consistent with the local appearance of high-pressure metamorphic rocks82. Furthermore, the increased carbon-rich sedimentary rocks would lead to reduced frictional strength, which promoted crustal thickening in the Paleoproterozoic mountain belts80.

Mid-Paleoproterozoic accretion-to-collision orogens that developed between and at the margins of cratons and/or large continental blocks (Fig. 9b) resulted in the formation of the supercontinent Columbia, which would have contained many large Himalayan-style orogenic belts and plateaus10,63,72,83, as recorded by higher peak metamorphic pressures (Fig. 1a) and the occurrence of HP eclogites and collisional orogenic belts worldwide8,70,71,83. Deeper and cooler subduction and enhanced collisional orogenesis can be attributed to higher lithospheric strength that is a direct consequence of cooling of the mantle and the emergence of orogenic (plate tectonic) styles more akin to the modern style (Fig. 9b). During collisional orogenesis, the hinterland of the orogenic crust underwent high-pressure metamorphism to form HP granulite and eclogite facies metamorphic belts with abundant metamorphic zircon, garnet, and rutile26,70. In the orogenic forelands, the basement rocks were strongly contracted and deformed to form large-scale fold-and-thrust belts58, as exemplified by the deformation of the Songshan foreland sequence.

The long-term uplift and unroofing of Himalayan-style orogens during the late Paleoproterozoic led to strong tectonic denudation and silicate weathering of evolved continent crust, as evidenced by detrital zircon and rutile in the foreland/cratonic basins, such as the lower Wufoshan Group (<1.77 Ga) reported here, and the significant increase in continent-derived seawater Sr signal between 2.0–1.7 Ga (Fig. 1b). The orogens were largely denuded by the onset of the eponymous ‘Boring Billion’ (1.75–0.75 Ga)84. Younger (<1.8 Ga) foreland, intra-cratonic and cratonic platform sequences, including the lower Wufoshan Group (Fig. 8c), record the stabilisation and final cratonisation of major cratons worldwide57 that paved the way for the appearance of the oldest known eukaryotes12 (Fig. 1c, d).

In conclusion, this study provides new constraints on the depositional-to-deformational evolution of the Paleoproterozoic Songshan Group foreland sequence, one of the oldest documented orogenic foreland basins in the North China Craton, from sedimentary and deformational perspectives. Importantly, it underscores the significance of multi-mineral geochronological analysis of key minerals from sedimentary archives in ancient orogenic forelands, which provide clues as to how sedimentation and metamorphism responded to changing orogenic style. Our research has shed light on changes in the orogenic styles during the Neoarchean to Paleoproterozoic and their possible influence on global biogeochemical cycles, which offers fresh perspectives on the dynamic interplay between solid and surficial Earth processes, contributing to a deeper understanding of our planet’s evolution towards a more habitable environment.

Methods
Zircon and rutile U–Pb isotope analyses
Zircon U–Pb dating was conducted at the Hubei Geological Research Laboratory, Ministry of Land and Resources of China, Wuhan. Cathodoluminescence (CL) images of zircons were obtained by a Gatan MonoCL4+ CL system attached to a Zeiss Sigma 300 field emission scanning electron microscope. Zircon U–Pb dating was performed using LA-ICP-MS utilising a GeoLas Pro 193 nm excimer ArF laser ablation system (Coherent Inc., Göttingen, Germany) attached to an Agilent 7700x ICP-MS. The spot diamter was 32 μm. Zircon 91500 was analysed twice every five analyses as an external standard, and zircons GJ-1 and Plešovice were measured as monitoring standards. All zircon standards yield ages consistent with the recommended values within error (see details in Supplementary Data 1). The synthetic silicate glass NIST SRM 610 was used as the standard to calibrate the trace element compositions.

Rutile U–Pb dating and trace element analysis were conducted at the State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, by LA-ICP-MS utilising a GeoLas HD 193 nm excimer ArF laser ablation system (Coherent Inc., Göttingen, Germany) and an Agilent 7900 ICP-MS. All data were acquired by single spot ablation at a spot size of 44 μm. Each measurement consisted of 20 s of acquisition of the background signal followed by 50 s of ablation signal acquisition. Rutile standard R632 was analysed twice every eight analyses as an external age standard, and rutile RMJG was measured as a monitoring standard. All standard ages were consistent with the recommended reference values (see details in Supplementary Data 1). The NIST 610 was used to calibrate trace elements. Off-line selection and integration of background and analyte signals, time-drift correction and quantitative calibration of trace element analyses, and data reduction followed the protocols given by refs. 16,85. Zircon and rutile U–Pb isotope and trace element results are presented in Supplementary Data 1.

40Ar/39Ar geochronological analysis
The amphibole and mica 40Ar/39Ar analyses were conducted at the Western Australian Argon Isotope Facility at Curtin University, Australia. The detailed analytical procedure and the relative abundance of Ar isotopic data are provided in Supplementary Note and Supplementary Data 3, respectively. The 40Ar/39Ar plateau age diagram is shown in Supplementary Fig. 9.

Estimate of maximum depositional ages
The maximum depositional ages (MDA) of sedimentary rocks can be estimated based on different methods. The widely used methods include the youngest single grain (YSG), youngest cluster overlapping with 1σ or 2σ uncertainties (YC1σ, YC2σ), and youngest statistical peak (YSP)38,39. For early Precambrian detrital zircons, the age of the youngest single grain is not appropriate because of measurement uncertainties, potential Pb loss and later hydrothermal modification86. The ±2% analysis error of LA-ICP-MS zircon U–Pb dating would have a significant influence on the resulting measured ages for old zircons (e.g., ±50 Ma uncertainty for a 2500 Ma zircon). Thus, for the early Precambrian sedimentary rocks without significant Pb loss, the weighted mean age of the youngest peak (YSP) or youngest cluster overlapping with 1σ (YC1σ) or 2σ uncertainties (YC2σ) would be the most appropriate and robust estimate of MDA (~98% confidence). In this study, we use the YC1σ as the estimate of the MDA (Supplementary Table S1). The calculation of MDA was conducted using the Python-based code, detritalpy87.

Time series analysis
Time series regression analysis was conducted on the global datasets of thermobaric ratios (T/P) and peak pressure (P) of global metamorphic rocks during crustal metamorphism. The metamorphic data set is based on refs. 8,88, with the addition of recently reported Paleoproterozoic HP metamorphic rocks. We smoothed the data with a LOESS (locally weighted scatter plot smoothing) regression method using the bootstrap function in Acycle v2.689. The number of bootstrap samplings was 1000. The shaded envelopes in corresponding curves indicate the range of 1σ and 2σ uncertainty (Fig. 1a, b). The LOESS regression can create statistically robust curves that fit through the data to assess general trends of crustal metamorphism and isotopes on the planetary scale.

Peer review rounds
[{"round": 1, "reviewer_comments": {"reviewer_1": "During the late Archean to Paleoproterozoic, the Earth's deep and surficial reservoirs underwent\ndramatic changes, as evidenced by a number of indications, which are essential to comprehending the\nvariation and interaction of Earth’s solid and surface systems. Nevertheless, the transformative\nmechanism by which plate subduction and plate boundary evolved at the critical Archean to\nPaleoproterozoic juncture still remains enigmatic. This contribution reports the identification and life\ncycle of an ancient Paleoproterozoic foreland basin in the North China Craton, one of the oldest foreland\nsuccessions in the world, and highlights the long-term evolution from ca. 2.5-2.47 Ga deposition\ninitiated by warm subduction and Altaid-style “soft” micro-continental collision and deformation-uplift-\ndenudation due to ca 1.97-1.85 Ga Himalayan-style continental collision. This study adds to our\nunderstanding of Earth's early evolution by shedding light on the multiple stages of source-and-sink\nhistory of the foreland sediments in response to late Archean to Paleoproterozoic orogenic episodes as\nwell as potential influences on the dramatic variations of surficial processes and conditions on early\nEarth. Despite that, there are still some concerns with this contribution, prompting me to recommend a\nminor revision prior to publishing.\nMajor concerns:\n(1) Priority one is the connection between the tectonic evolution of the two episodes of orogenesis in\nNorth China Craton. Their respective tectonic evolution has been clearly manifested by the convincing\nworks of the authors’ group in recent years, however, the successive evolution history in the west of the\n“Proto-Eastern Block” (Figure 7A) is, in my viewpoint, an important element for constructing the\ntectonic architecture from “supercraton” to “supercontinet” over a timeframe of ~500 million years (i.e.,\nfrom ~2.5 Ga to ~1.98 Ga) (Figures 7A-B). In any case, an ancient oceanic basin lay between the Proto-\nEastern Block and Ordos Block. If this ocean was consumed by subduction zone along the western\nmargin of the Proto-Eastern Block, (i.e., the COB transferred to an active margin), is there any geological\n(magmatic, metamorphic, or accretionary) record for the successive prolonged subduction from the late\nArchean to Paleoproterozoic? Alternatively, if the COB was indeed a passive margin, were sediments\nequivalent to the passive boundary deposited and preserved? In other words, the tectonic scenario\nbetween two episodes of orogenesis in the Archean and Proterozoic is likely a crucial link for elucidating\nthe transformative mechanism for the systematic changes from deep to surface in early Earth.\n(2) The structural style of the foreland deposits matches with the characteristics of the thrust-fold belts\nat the middle-to-upper crustal-level. Although rutiles have been utilized to constrain the metamorphic\ntemperature (T) for their presumed sources, it is necessary to directly quantify the metamorphic T for\nthe schists in the thrust-fold belts and to, on the other hand, mutually verify the provenance of the\ndetrital rutiles.\n(3) There must be some clerical errors in the text depicting the age peaks for the geochronologic\nspectra (Figure 6). For instance in line 173, one of the age peaks for detrital rutile is written as “1.87 Ga” but is\nshown as “1.86 Ga” in Figure 6E; in line 247, age peaks for detrital zircons are written as “1.93 Ga and\n1.84 Ga” but are shown as “1.94 Ga and 1.83 Ga” in Figure 6G; etc. Please check thoroughly the\nconsistency of the figure and text for the zircon and rutile U-Pb geochronology.\nA few specific comments:\n(1) Lines 34-35, change “one of most…” to “one of the most…”;\n(2) Line 246, change “(Fig. 6G)” to “(Fig. 6F)”;\n(3) Figures 3A and 3B should have photographic scale.", "reviewer_2": "After carefully reviewing this submission, I don't think it can be published in NC, I recommend reject, the\nmain reasons for my suggestion are as follows.\n1. It seems that this study is based on a relatively small number of samples - especially given that\nyou are trying to resolve large scale issues relating to the temporal development of the Paleoproterozoic\nforeland successions. In some cases, I found it difficult to actually determine how many samples had\nbeen used. It is imperative that you provide a clear statement regarding the exact number of samples\nused for each type of analysis - it is absolutely critical that it you can demonstrate that you have used\nsufficient samples to justify the conclusions that you have reached.\n2. This study has no novelty and too local, the methods are simple, many publications had defined the\ntwo-stages orogenesis model of the North China Craton, Archean mélange and Paleoproterozoic\nforeland successions developed within the Trans-North China Orogen (see Professor M. Santosh’s group\npapers, Professor Guo-chun Zhao’s group papers, Professor Ming-guo Zhai’s group papers, Professor T.\nKusky’s group papers, etc.)\n3. Many concepts and descriptions are confused in the manuscript, for example, Nuna is different to\nColumbia supercontinent, see JG Meert et al. 2012 Gondwana Research; JG Meert and M Santosh 2017\nGondwana Research. Also, many Chinese strata names confused me, didn't explain them clearly. The\ncitations are not rigorous in the manuscript, who was the first to propose this concept of Columbia\nsupercontinent, the evolution models of Columbia supercontinent and North China Craton??? The\nauthors even didn’t add any references in many paragraphs/sentences, see lines 323, 360-367, etc.\n4. The manuscript mixed use of full name and abbreviations here and there. For example, North China\nCraton and NCC; Circa and Ca.; Formation and Fm. (See Lines 52, 110, 123, 127-128, 140, 158, 201, 206,\n317, 344, 661, 631).\n5. The logic of this manuscript is weak, this work can’t better define the differences and controversies\namong the models. The maximum depositional ages of the detrital zircons can’t be represented the\ndepositional age of the strata, not to mention such old metamorphic strata; The age analysis lacks\nevidence, you can't say pb-loss casually. The authors can’t discuss more contributions about the\ncontroversies among the models of lines 260-267 and can’t get this conclusion of lines 288-290 without\nthe evidence.\n6. I found the conclusions to be somewhat weak - they really do not stress the main contributions\nof the paper. The Conclusions need to be improved.\n7. Comments on the figures:\nFigure 1. Nuna or Columbia??? The timing of supercontinents are right?\nFigures 2-5. the authors discussed the structures, not even providing the nature of faults in the Figure 2;\nthe field interpretations seem unclear in the Figures 3-5; the authors should define the abbreviations in\nthe figures. No any field data on the foliations and lineations in the Figure 3. Confused the COB and\nTNCO.\nFigure 6. How does the author distinguish between the detrital/metamorphic ages？\nFigure 7. Too general and it is difficult to compelling to the readers because many places lack\nevidence, especially the time limits; also confused the COB and TNCO. It seems that the authors just want to mix\neverything together and doesn't clarify geological history very well. This manuscript does not contribute\nin terms of time constraints, it is too broad.", "reviewer_3": "Huang and colleagues present a detailed study of the structural history, basin evolution, and\nprovenance of Paleoproterozoic sedimentary rocks in the North China Craton. They integrate these datasets to infer\na contrast in the tectonic style of orogenesis and continental assembly in the North China Craton (NCC)\nbetween the late Neoarchean and early Paleoproterozoic. The paper concludes by discussing the\npossible influences the purported transition in global tectonic regimes across the Archean-Proterozoic\nmay have had on the wider Earth system.\nLinking solid Earth processes and tectonic regimes to the wider Earth system is a highly active area of\nresearch and of interest to a broad cross section of the scientific community. Multi-disciplinary studies\nsuch the one presented in this paper are essential to developing a holistic understanding of relationship\nbetween tectonic processes and surface environments through deep time. The paper by Huang and\ncolleagues takes the novel approach of studying the history of foreland sedimentary basins to document\nchanges in tectonic regimes across the Archean-Proterozoic transition and its impact on global\ngeochemical cycles. The paper is mostly well-written and is exceptionally and informatively illustrated. In\nmy opinion, this paper would make an excellent contribution to Nature Communications. However, I\nhave a number of queries regarding the provenance data that should be addressed before publication.\nDetrital Rutile evidence\nOne of the main pieces of evidence cited for a change in orogenic style from hot ‘soft’ collision\nin the Neoarchean to hard ‘cold’ collision in the Paleoproterozoic is the near absence of\nNeoarchean detrital rutile in the Songshan Group contrasting with the abundance of\nPaleoproterozoic detrital rutile grains in the Wufoshan Group. This interpretation is consistent\nwith the tendency of rutile to grow in high-P metamorphic rocks, which are more likely to be\nexhumed and eroded into adjacent sedimentary basins in ‘colder’ orogens. Some important\ncaveats to this interpretation are the tendency of rutile to recrystallise to ilmenite or titanite\nduring the greenschist- to amphibole facies of a prograde metamorphic path (e.g., Ashley and Law, 2015, contrib. Mineral. Petrol., 169) and the relatively low closure temperature of Pb\ndiffusion in rutile (~500-600 C = greenschist-amphibolite facies conditions).\nThe fact that the Songshan Group has been metamorphosed to greenschist facies raises the possibility\nthat Neoarchean detrital rutile grains were originally present in these sedimentary rocks but were\nsubsequently recrystallised or had their U-Pb ages reset during Paleoproterozoic orogenesis. If this were\nthe case, the reported absence of Neoarchean detrital rutile in the Songshan Group could not be\nattributed to the absence of high-P Neoarchean metamorphic rocks in their source region.\nThe authors need to acknowledge these inherent caveats to interpreting rutile U-Pb ages in\nmetamorphic rocks. They should then justify their interpretation that the detrital rutile grains in\nthe Songshan Group are neocrystallised grains that grew during 2.0—1.7 Ga metamorphic event\nrather than being recrystallised or reset older detrital grains. I believe several observations already presented in the\npaper support the original interpretation made by the authors and should be more explicitly highlighted:\n• Some older detrital rutile grains are preserved in the Songshan Group (Line 172). This suggest\ntemperatures were not high enough during Paleoproterozoic greenschist facies metamorphism to reset\nthe U-Pb system of rutile. Given that resetting of the U-Pb system is a function of grain size, this\nargument could be further supported by demonstrating that the older detrital grains in these samples\nare of a similar size to the dominant 2.0—1.7 Ga population. The authors report the size of rutile grains\nin the supplementary files, so quantifying the relationship between grain size and age should be simple.\n• Zr-in-Rutile temperatures are low and uniform, which would not be expected if these were originally\nNeoarchean detrital grains derived from high-T metamorphic rocks elsewhere in the NCC. Zr diffusion in\nrutile is very slow and probably has a closure temperature on the order of ~700 C. This makes it is\nunlikely that the Zr concentrations of rutile would have been re-equilibrated during greenschist facies\nmetamorphism at 2.0—1.7 Ga. Thus, the authors can rule out that the abundant 2.0—1.7 Ga rutile\ngrains in the Songshan Group represent originally ~2.5 Ga detrital grains that have had their U-Pb\nsystematics reset during the 2.0—1.7 Ga event.\n• The samples appear to be compositionally (super-)mature Qtz-rich rocks that are presumably Ca- and\nFe-poor. Ca- and Fe-poor bulk compositions would not favour conversion of detrital rutile grains to\nilmenite or titanite during prograde metamorphism. Thus, the Songshan Group has a favourable\ncomposition to preserve older detrital rutile grains, if they were present (and as above, the U-Pb data\nindicates that some older ages are indeed preserved).\n• The authors note that rutile in Songshan Group are aligned with dominant foliation as evidence of\nmetamorphic origin. I agree, but it would be nice to show a photomicrograph in the main body of the\nmanuscript demonstrating this textural evidence.\nDetrital zircon evidence\nThe authors suggest that only the Wufoshan Group contains detrital zircons derived from metamorphic\nsources, suggesting that only the Paleoproterozoic orogenic event produced a sufficient volume of\nthickened orogenic crust to be sampled by the sedimentary archive.\nThe only evidence supporting this interpretation that is presented in the main body of the paper is that\n‘…only the Wufoshan Group contains zircons with numerous core-rim structures…’ (lines 286—287).\nHowever, from the CL images of detrital zircon grains from the Songshan Group presented in the\nsupplementary material (Fig. S5), I can see several grains that apparently have secondary overgrowths or\nzones that truncate oscillatory-zoned core domains (e.g., grains 13, 9, 2 on Panel A, grains 14 and 16 on\npanel B, grain 3 on panel C, grains 17 and 32 on panel E, grain 2 and 26 on Panel F). The argument that\ncore-rim structures are more common in detrital zircons from the Wufoshan Group would be more\ncompelling if the authors could quantify how common these textures are in both the Songshan and\nWufoshan groups (i.e. what % of grains have core-rim structures in each group?).\nThe authors also cite Fig. S9 as containing additional evidence for abundant metamorphic-derived\nzircons in the Wufoshan Group (lines 286—287) but do discuss the significance of the data presented in\nthis supplementary figure. Fig S9 summarises REE patterns for zircons from the Wufoshan Group and\nshows that some grains have HREE-depleted signatures, which are typical of zircon that has co-\ncrystallised with garnet, potentially indicating high-P metamorphism. However, these REE-patterns are\nnot tied to the corresponding U-Pb age of the grains. Furthermore, the HREE-depleted measurements\napparently come from the cores of zircon grains that are surrounded by metamorphic rims, which the\nauthors appear link to the main Paleoproterozoic metamorphic event. Based on this data, I have two\nqueries:\n(1) How can the authors be certain these HREE-depleted metamorphic zircons aren’t pre-2.0 Ga grains\nand hence actually provide evidence for high-P metamorphism related to the earlier (Neoarchean)\norogenic event(s). I note from Fig. 6F that the Wufoshan Group contains numerous pre-2.0 Ga detrital\ngrains. If the authors could demonstrate that all of the HREE-depleted zircons in the Wufoshan Group\nare ~1.7-2.0 Ga, it would strengthen the interpretation that the Paleoproterozoic metamorphic event\nwas characterised by higher pressure metamorphism compared to earlier orogenic events.\n(2) I am curious as to why similar detrital zircon REE data has not been presented from the\nSongshan Group. A comparison of time-constrained REE data from detrital zircons from both the Wufoshan and\nSungshan groups would make for a much more balanced comparison of the metamorphic style of\nNeoarchean vs. Paleoproterozoic orogenesis based on detrital zircon record (i.e., demonstrate that\nNeoarchean detrital zircon populations lack HREE-depleted signatures, whereas Paleoproterozoic zircon\npopulations do contain them).\nMinor comments (Line-by-line)\nLine 1 (title): I would remove ‘dramatic’ from the title. Much of the evidence for a change in in\norogenic style in the NCC is from models and datasets beyond the foreland basin deposits that this paper focuses\non. I think the evidence from the sedimentary record is more subtle but compelling nonetheless (as is\nalways the case for reconstructing orogenic histories from sedimentary rocks).\nLine 53—54: Somewhat redundant to describe an ‘Alpine-style’ fold-and-thrust belt associated with a\n‘Himalayan-style’ collisional orogeny. Describing it as a fold-and-thrust belt developed during a\nHimalayan- (or Alpine) style collision would suffice.\nLine 70: Replace ‘loosely’ with ‘incompletely’ documented.\nLine 113: The clasts (not ‘gravels’) in the conglomerate are aligned with the tectonic foliation.\nLines 133: suggest rewording: The sandstones is composed of well-rounded detrital quartz grains that\ncontain dusted rims and quartz overgrowths.\nLine 216: Typo: ‘provenances’ should be provenance.\nLine 217: Typo: ‘filtration’ should be filtering.\nLine 276: ‘…could be linked to a secular change of orogenesis’. This clause isn’t needed here. The point\nbeing made is that rutile forms in high-pressure metamorphic rocks. This is true regardless of when high-\npressure rocks first appeared in the geological record (which is more relevant when this point is\ndiscussed later in the paper).\nLine 278: Typo: ‘event’ should be events.\nLine 282: Typo: ‘metamorphic origins’ should be metamorphic origin.\nLine 288: ‘indicate’ should be replaced with ‘….are interpreted to reflect….’ or ‘record’.\nLine 295: unclear what is meant by ‘….where the largest accretion and crustal growth occurred’.\nLargest accretion and growth compared to what? The local geology or the globally? Or do you\nmean Altaid-style orogens are the sites of significant crustal accretion and growth?\nLine 299: final sentence of this paragraph is vague. Do you mean rutile and low-Lu and low-Lu/Dy zircons\nare rare at this time in the global detrital record? If you want to make this point, you need to explain the\nsignificance of low-Lu and low-Lu/Dy zircons.\nLine 305: I’m not convinced that high-pressure granulites (and to some extent eclogites) provide\nevidence of ‘cold subduction’. Granulites aren’t common in ‘cold’ subduction zones and perhaps only\nLawsonite eclogites provide compelling evidence for ‘cold’ subduction. If there are metamorphic rocks\nthat do record low T/P thermal gradients in the NCC, these should be highlighted.\nLine 317—319: As written it this sentence implies that only the tectonic events in the NCC influenced\nthe wider Earth system. I think the authors mean that the changes recorded in the NCC are typical of\nthose preserved in many early Paleoproterozoic terranes, suggesting a global link between a transition\nin tectonic regime and surficial environments. As such, it would be helpful to cite some other examples\nwhere similar Archean-Paleoproterozoic tectonic transitions are preserved in the structural,\nsedimentary, magmatic record (e.g., Western Australia, North America, South Africa…).\nLine 319—320: Are you saying this style of late Archean cratonisation is typical of the NCC or all cratons?\nIf the latter, need to support with references.\nLine 325: Typo: ‘Nutrition’ should be nutrients. For those not familiar with biochemical cycles, it would\nbe useful to elaborate on what these nutrients actually are and how they form an important component\nof orogenic rocks.\nLine 334—336: Might be helpful to remind the readers that these are quartz-rich clastic rocks, which\nprovides evidence that the more labile minerals in their source TTGs/greenstones were indeed\ndestroyed during weathering.\nLine 354—356: A citation to Cawood et al. 2022 Reviews of Geophysics, v. 60 (4) would be appropriate\nhere.\nLine 358: ‘higher peak metamorphic pressures from minerals or increased high-pressure rock record’.\nThis is vague, aren’t these the same thing? i.e., high-pressure rocks are defined by having high-pressure\nminerals.\nLine 362—367: Unclear if this is a general statement about all orogens or just the study area.\nLine 368—377: The concluding paragraph linking the stabilisation of continents to the boring billion and\nthe appearances of eukaryotes is essentially a throw-away line. In the context of this paper, the link\nbetween continental stabilisation, the boring billion, and eukaryote evolution is not clear. Is it to do with\nocean chemistry? tectonics? What new insights on these topics does this paper make? A stronger finish\nwould be to reinforce the sedimentary response to changing orogenic styles, which is really what this\npaper does a nice job of doing.\nLine 379: (Methods). No data for reference materials is presented in the supplementary material. It is\nstated that ‘all ages are consistent with recommended values’ but the original data for the reference\nmaterials must be included so their veracity can be assessed independently.\nGeneral comments on grammar\n• The definitive article (the) is used incorrectly in several places throughout the manuscript. I\nencourage the native English-speaking co-authors or journal type editors to revise.\n• A more pedantic point, but the use of forward slashes (/) obscures the intended meaning of the text in\nseveral places. It’s not clear if the forward slash means ‘or’, ‘and’, or is taking the place of a hyphen. For\nexample, arc/micro-continent collision. Is this describing a collision between an arc and a\nmicrocontinent (arc-microcontinent collision), or is it indicating there were multiple collisions, some\ninvolving arcs and microcontinents, others involving only arcs or only microcontinents? I suggest\nreplacing ‘/’ with ‘and’ or with ‘or’ for clarity.", "reviewer_author_response": "Point-by-point response to the reviewers’ comments (Reply in BLUE)\nWe are thankful to the reviewers for the thorough reviews, constructive comments, and\nsuggestions, which have been very helpful for us to improve the quality of the paper. We\nappreciate these comments and suggestions, and implemented careful revisions and addressed all\nconcerns accordingly. The detailed revisions can be found in the “Manuscript with changes\ntracked (in red)”, and the point-by-point response as follows (reply in blue).\n=====================================================================\nReviewer #1 (Remarks to the Author):\nDuring the late Archean to Paleoproterozoic, the Earth's deep and surficial reservoirs underwent\ndramatic changes, as evidenced by a number of indications, which are essential to\ncomprehending the variation and interaction of Earth’s solid and surface systems. Nevertheless,\nthe transformative mechanism by which plate subduction and plate boundary evolved at the\ncritical Archean to Paleoproterozoic juncture still remains enigmatic. This contribution reports\nthe identification and life cycle of an ancient Paleoproterozoic foreland basin in the North China\nCraton, one of the oldest foreland successions in the world, and highlights the long-term\nevolution from ca. 2.5-2.47 Ga deposition initiated by warm subduction and Altaid-style “soft”\nmicro-continental collision and deformation-uplift-denudation due to ca 1.97-1.85 Ga\nHimalayan-style continental collision. This study adds to our understanding of Earth's early\nevolution by shedding light on the multiple stages of source-and-sink history of the foreland\nsediments in response to late Archean to Paleoproterozoic orogenic episodes as well as potential\ninfluences on the dramatic variations of surficial processes and conditions on early Earth.\nDespite that, there are still some concerns with this contribution, prompting me to recommend a\nminor revision prior to publishing.\nWe appreciate Prof. Wenjiao Xiao for the positive recommendation and constructive comments.\nWe have implemented relevant revisions and addressed all concerns accordingly.\nMajor concerns:\n(1) Priority one is the connection between the tectonic evolution of the two episodes of\norogenesis in North China Craton. Their respective tectonic evolution has been clearly\nmanifested by the convincing works of the authors’ group in recent years, however, the\nsuccessive evolution history in the west of the “Proto-Eastern Block” (Figure 7A) is, in my\n1\nviewpoint, an important element for constructing the tectonic architecture from “supercraton” to\n“supercontinet” over a timeframe of ~500 million years (i.e., from ~2.5 Ga to ~1.98 Ga) (Figures\n7A-B). In any case, an ancient oceanic basin lay between the Proto-Eastern Block and Ordos\nBlock. If this ocean was consumed by subduction zone along the western margin of the Proto-\nEastern Block, (i.e., the COB transferred to an active margin), is there any geological (magmatic,\nmetamorphic, or accretionary) record for the successive prolonged subduction from the late\nArchean to Paleoproterozoic? Alternatively, if the COB was indeed a passive margin, were\nsediments equivalent to the passive boundary deposited and preserved? In other words, the\ntectonic scenario between two episodes of orogenesis in the Archean and Proterozoic is likely a\ncrucial link for elucidating the transformative mechanism for the systematic changes from deep\nto surface in early Earth.\nThank you for this insightful comment and discussion.\nIndeed, the long-term evolution of the North China Craton (NCC) is complex. Nevertheless, the\ntwo major tectono-magmatic-thermal events (orogenesis or cratonization) have been well\nidentified during the past two decades. However, several different tectonic models have been\nproposed based on the emphasis of different evidence. The core debate is about the detailed\nevolutionary history of the early Paleoproterozoic from 2.45 Ga to 2.0 Ga. For example, Zhai et\nal. (2005, 2011) suggested that this period experienced post-cratonisation rifting-subduction-\ncollision along three Paleoproterozoic mobile belts. Zhao et al. (2005, 2012) suggested that this\nperiod is characterized by prolonged subduction of a paleo-ocean since 2.56 Ga between the\nEastern Block and Western Block, which was terminated by collisional orogenesis at ca. 1.85\nGa. Kusky et al. (2003, 2016) suggested that there are multiple stages of accretionary and\ncollisional orogenic events from ca. 2.5 Ga to 1.8 Ga, which led to the outward growth of the\nNCC and final incorporation into the Columbia supercontinent. In these models, the Songshan\nsedimentary succession was interpreted as deposition along the extensional rift or cratonic\nmargin that unconformably overlain the Archean basement (Zhai et al., 2005), retro-arc foreland\nbasin (Zhao et al., 2012; Liu et al., 2012), or peripheral to retro-arc foreland basins (Kusky et al.,\n2016), respectively. The latter two models are very similar regarding the tectonic affinity of the\nsuccession, which is related to the eastward subduction of oceanic lithosphere beneath the\n(Proto-)Eastern Block.\nBased on our new datasets and compilation of regional magmatic, metamorphic, and\naccretionary records, we can constrain the Neoarchean arc–(micro)continent collision event that\n2\nterminated the westward subduction of the oceanic basin between the central arc system and the\nEastern NCC (we termed the Proto-Eastern Block). The arc-microcontinent collision may have\nbeen followed by a subduction polarity reversal event (e.g., Kusky, 2011; Wang et al., 2015;\nKusky et al., 2016), leading to the eastward subduction beneath the western margin of the Proto-\nEastern Block, which converted as an Andean-type active continental margin. The lowest section\nof the Songshan foreland is in response to the arc–(micro)continent collision (Fig. 8a), while the\nupper section may be a response to the long-term retro-arc sedimentation. The closure processes\nof the oceanic basin between the Proto-Eastern Block and Ordos Block remain poorly\nconstrained due to the limited outcrop of the Ordos Block, but a recent publication suggests a\ncomplex subduction-accretion process based on a summary of new regional data sets (Yin et al.,\n2023, ESR). During the Paleoproterozoic orogenesis, the previous Songshan foreland\nsuccessions were converted into a fold-and-thrust belt (Fig. 8b). Our data provide a better\nconstraint on these two stages of orogenesis and their distinctive styles (e.g., Altaid-style vs.\nHimalayan-style).\nWe have revised the relevant paragraphs to clarify the 2.5–2.0 Ga evolution in the main text (see\nLines 284–289), along with a detailed summary of the geological background and available\ntectonic models of the NCC in the Supplementary Note.\nZhai, M., Guo, J. & Liu, W. Neoarchean to Paleoproterozoic continental evolution and tectonic\nhistory of the North China Craton: a review. J. Asian Earth Sci. 24, 547-561 (2005).\nZhai, M. Cratonization and the Ancient North China Continent: A summary and review. Science\nChina Earth Sciences. 54, 1110-1120 (2011).\nZhao, G., Sun, M., Wilde, S. A. & Li, S. Late Archean to Paleoproterozoic evolution of the North\nChina Craton: key issues revisited. Precambrian Res. 136, 177-202 (2005).\nZhao, G. et al. Amalgamation of the North China Craton: Key issues and discussion. Precambrian\nRes. 222-223, 55-76 (2012).\nKusky, T. M. & Li, J. Paleoproterozoic tectonic evolution of the North China Craton. J. Asian Earth\nSci. 22, 383-397 (2003).\nKusky, T. M. et al. Insights into the tectonic evolution of the North China Craton through comparative\ntectonic analysis: A record of outward growth of Precambrian continents. Earth-Sci. Rev. 162,\n387-432 (2016).\nLiu, C. et al. Detrital zircon U–Pb dating, Hf isotopes and whole-rock geochemistry from the\nSongshan Group in the Dengfeng Complex: Constraints on the tectonic evolution of the Trans-\nNorth China Orogen. Precambrian Res. 192-195, 1-15 (2012).\nKusky, T. M. Geophysical and geological tests of tectonic models of the North China Craton.\nGondwana Res. 20, 26-35 (2011).\nevent in the North China Craton. Lithos. 220-223, 133-146 (2015).\nYin, C. et al. Paleoproterozoic accretion and assembly of the Western Block of North China: A new\nmodel. Earth-Sci. Rev., 104448 (2023).\n(2) The structural style of the foreland deposits matches with the characteristics of the thrust-fold\nbelts at the middle-to-upper crustal-level. Although rutiles have been utilized to constrain the\nmetamorphic temperature (T) for their presumed sources, it is necessary to directly quantify the\nmetamorphic T for the schists in the thrust-fold belts and to, on the other hand, mutually verify\nthe provenance of the detrital rutiles.\nThank you for highlighting this. We have supplemented the P–T conditions of representative\nsamples from the quartz-mica schists based on Ti-in-biotite geothermometer and phase equilibria\nmodelling (Supplementary Note, Figure S11, Table S3). Our results confirm that the majority of\nrutiles in the Songshan Group are of metamorphic origin formed during the Paleoproterozoic\ncollisional event. The Zr-in-rutile temperature is comparable to the Ti-in-biotite temperature of\nthe schist.\n(3) There must be some clerical errors in the text depicting the age peaks for the geochronologic\nspectra (Figure 6). For instance in line 173, one of the age peaks for detrital rutile is written as\n“1.87 Ga” but is shown as “1.86 Ga” in Figure 6E; in line 247, age peaks for detrital zircons are\nwritten as “1.93 Ga and 1.84 Ga” but are shown as “1.94 Ga and 1.83 Ga” in Figure 6G; etc.\nPlease check thoroughly the consistency of the figure and text for the zircon and rutile U-Pb\ngeochronology.\nThank you for this important point. We carefully checked the figures and corresponding\ndescriptions in the main text, which now are consistent between the main text and figures.\nA few specific comments:\n(1) Lines 34-35, change “one of most…” to “one of the most…”;\nCorrected.\n(2) Line 246, change “(Fig. 6G)” to “(Fig. 6F)”;\nCorrected.\n4\n(3) Figures 3A and 3B should have photographic scale.\nThanks. We added the scale.\nWenjiao Xiao\nWe deeply appreciate Prof. Wenjiao Xiao for the above constructive comments.\n=====================================================================\nReviewer #2 (Remarks to the Author):\nAfter carefully reviewing this submission, I don't think it can be published in NC, I recommend\nreject, the main reasons for my suggestion are as follows.\nWe appreciate Reviewer #2 for the critical comments and suggestions, most of which have been\nessential for us to improve the quality of the manuscript. Nonetheless, it appears that there\nmight be a slight misapprehension regarding the core focus of our paper.\nOur study focuses on elucidating the styles of two stages of orogenesis in the Neoarchean and\nPaleoproterozoic and their possible impacts on the surficial environment. This multifaceted\nunderstanding is derived from integrated structural, petrological, and geochronological\ninvestigations on one of the most ancient foreland basins in the North China Craton (NCC),\nalong with big-data comparison. It is important to clarify that our intention extends beyond the\nsingular aim of deciphering the regional tectonic evolution of the NCC, as mentioned by the\nreviewer.\n1. It seems that this study is based on a relatively small number of samples - especially given that\nyou are trying to resolve large scale issues relating to the temporal development of the\nPaleoproterozoic foreland successions. In some cases, I found it difficult to actually determine\nhow many samples had been used. It is imperative that you provide a clear statement regarding\nthe exact number of samples used for each type of analysis - it is absolutely critical that it you\ncan demonstrate that you have used sufficient samples to justify the conclusions that you have\nreached.\nanalyses, 90 trace elemental analyses of rutile, 4 Ar-Ar dates, 171 mineral chemical analyses)\nand literature compilation as we stated in the main text (including in the previous version)\n(Supplementary Data 1–4). The numbers of detrital zircon ages and rutile ages used in the\ndiscussion are 1365 and 136, respectively, which cover the main units of the Songshan and\nWufoshan groups and are sufficient to make a convincing analysis of their sedimentary-to-\ndeformational evolution. Furthermore, we conducted comparisons with global rutile and detrital\nzircon datasets (Figs. 1a, 6, 7g) and have revised relevant figures (Supplementary Figs. S6, S7)\nand text to enhance clarity.\nWe have labelled the analysis numbers of zircons and rutiles in each sample in Fig. S6a (now\nFig. S7a) in the previously submitted version. To make it clearer, we also added the analysed\nnumbers of every sample in Fig. S6 in this revised version.\n2. This study has no novelty and too local, the methods are simple, many publications had\ndefined the two-stages orogenesis model of the North China Craton, Archean mélange and\nPaleoproterozoic foreland successions developed within the Trans-North China Orogen (see\nProfessor M. Santosh’s group papers, Professor Guo-chun Zhao’s group papers, Professor Ming-\nguo Zhai’s group papers, Professor T. Kusky’s group papers, etc.)\nThanks for this critical comment, but the reviewer may have misunderstood the innovation points\nof this manuscript.\nAs we have responded, the tectonics of the NCC has been a hot topic, with one of most important\nprogresses being the documentation of two stages of tectono-magmatic-thermal events in the\nNeoarchean (ca. 2.5 Ga) and Paleoproterozoic (ca. 1.9 Ga) (attributed to two-episode orogenesis\nby some) in the past two decades (references mentioned by Reviewer #2). However, the nature\nand detailed process of these two stages of events (orogenesis) remain debated, with several\nmodels being proposed to explain the regional tectonic evolution of the NCC (Supplementary\nNote). Thus, this is not to say all tectonic models on regional tectonics are perfect and no further\nresearch on regional tectonics and more general scientific questions is needed.\nRather, the in-depth discussion and constraints on some general scientific questions in\nEarth Science regarding the styles of orogenesis and plate tectonics and their\nenvironmental effects remain limited and further investigations, which have been the focus\n6\nand frontier of recent studies (e.g., Zhai and Peng, 2020; Cawood et al., 2022). The NCC,\nwith its two stages of ‘orogenic’ events, offers a unique natural laboratory for investigating these\nexciting scientific inquiries.\nIn this contribution, we focus on such a hot research topic from unique sedimentary and\nstructural perspectives of the orogenic foreland, one of the oldest foreland basins from the NCC.\nOur integrated field, structural, petrological, and geochronological data sets allow us to better\nconstrain the distinctive orogenic styles in the Neoarchean and early Paleoproterozoic.\nFurthermore, we establish connections between orogenesis and surface environmental changes,\nyielding fresh insights into the evolution of orogenic styles and the interactions between solid\nEarth processes and near-surface systems.\nWe believe that Reviewer #2 might be aware of this research trend and will understand the novel\naspects and motivations of our study as we explained in Introduction and Discussion in detail.\nZhai, M. & Peng, P. Origin of early continents and beginning of plate tectonics. Sci. Bull. 65, 970-\n973 (2020).\nCawood, P. A. et al. Secular Evolution of Continents and the Earth System. Rev. Geophys. 60,\n(2022).\n3. Many concepts and descriptions are confused in the manuscript, for example, Nuna is different\nto Columbia supercontinent, see JG Meert et al. 2012 Gondwana Research; JG Meert and M\nSantosh 2017 Gondwana Research. Also, many Chinese strata names confused me, didn't explain\nthem clearly. The citations are not rigorous in the manuscript, who was the first to propose this\nconcept of Columbia supercontinent, the evolution models of Columbia supercontinent and\nNorth China Craton??? The authors even didn’t add any references in many\nparagraphs/sentences, see lines 323, 360-367, etc.\nThanks for this critical comment. We reply to these comments one by one.\n(1) Terminology of Nuna vs. Columbia:\nThe debate about the terminology of Paleoproterozoic supercontinent is not the main focus of\nthis manuscript, but we simply explain why we used the ‘Columbia/Nuna’ in the first version.\nThe Paleoproterozoic supercontinent in the past two-decade literature has been variably termed,\nsuch as ‘Nuna’ (Hoffman 1997), and ‘Columbia’ (Rogers and Santosh, 2002). The Nuna initially\n7\nrefers to the connected continent of five large cratons including Baltica-North America-Siberia-\nNorthern and Western Australia, which have been regarded as the core of the Paleoproterozoic\nsupercontinent in later studies. This is the basis for reconstructing the Paleoproterozoic\nsupercontinent. With time going on, more cratons have been linked and posited around the Nuna\n(e.g., Evans, 2003, Tectonophysics; Campbell and Allen, 2008, Nature Geoscience; Evans and\nMitchell, 2011, Geology; Mitchell et al, 2012, Nature, 2021 Nature Reviews Earth and\nEnvironment; Wan et al., 2015, Nature Communications). The original proposal of ‘Columbia’ is\nlargely based on evidence of rifts in India and North America (Columbia River) (Rogers and\nSantosh, 2002), however, this link seems to have not been widely used in later studies.\nThus, both Nuna and Columbia have been widely used to refer to the Paleoproterozoic\nsupercontinent in the last decades (see a historical review by Meert, 2012). Currently, most\nresearchers prefer to use the terms ‘Columbia (Nuna)’, ‘Nuna (Columbia)’, ‘Nuna/Columbia’\nand even ‘Columbia-Nuna’ to avoid the debate about terms as we did before (e.g., Ernst et al.,\n2008; Li et al., 2023, Earth-Science Reviews; Wu et al., 2022, G-cubed). A recent review by\nRoss Mitchell et al. (2021) may provide a possible solution to this issue, i.e. Nuna as a mega-\ncontinent (like Gondwana) in the core of supercontinent Columbia (although the configuration is\nstill debated).\nRespectfully, we revised our terminology to ‘Columbia’ in the whole manuscript to avoid\nambiguity following the reviewers’ suggestion, except for in the first appearance, where we\nwrote ‘Columbia, with the core of Nuna’.\n(2) References about the supercontinent:\nConsidering the limitation of the number of references, we just cited the key and indispensable\nreferences in the main text and put some in the Supplementary Information in the first version.\nAccording to the reviewer’s suggestion, we added some key references about the NCC and its\nlink with the Paleoproterozoic supercontinent in relevant places in the revised version (e.g., Zhao\net al., 2002; Kusky et al., 2007; Wu et al., 2018, 2022).\nLine 323: We add references here.\nLines 360-367: We add references here.\nMarshak, S. (Eds.), An Introduction to Structural Geology and Tectonics. McGraw-Hill, New\nYork, pp. 459–464 (1997).\nRogers, J. J. W. & Santosh, M. Configuration of Columbia, a Mesoproterozoic Supercontinent.\nGondwana Res. 5, 5-22 (2002).\nEvans, D.A. True polar wander and supercontinents. Tectonophysics, 362(1-4), pp.303-320 (2003).\nEvans, D. A. D. & Mitchell, R. N. Assembly and breakup of the core of Paleoproterozoic-\nMesoproterozoic supercontinent Nuna. Geology. 39, 443-446 (2011).\nCampbell, I.H. and Allen, C.M. Formation of supercontinents linked to increases in atmospheric\noxygen. Nature Geoscience, 1(8), pp.554-558 (2008).\nMeert, J. G. What's in a name? The Columbia (Paleopangaea/Nuna) supercontinent. Gondwana\nRes. 21, 987-993 (2012).\nMitchell, R. N., Kilian, T. M. & Evans, D. A. D. Supercontinent cycles and the calculation of absolute\npalaeolongitude in deep time. Nature. 482, 208-211 (2012).\nMitchell, R. N. et al. The supercontinent cycle. Nat. Rev. Earth Environ. 2, 358-374 (2021).\nWan, B., Windley, B. F., Xiao, W., Feng, J. & Zhang, J. E. Paleoproterozoic high-pressure\nmetamorphism in the northern North China Craton and implications for the Nuna\nsupercontinent. Nat. Commun. 6, 8344 (2015).\nLi, Z.X., Liu, Y. and Ernst, R. A dynamic 2000–540 Ma earth history: from cratonic amalgamation to\nthe age of supercontinent cycle. Earth-Science Reviews.104336 (2023).\nWu, C. et al. Paleoproterozoic Plate Tectonics Recorded in the Northern Margin Orogen, North\nChina Craton. Geochemistry, Geophysics, Geosystems. 23, e2022GC010662 (2022).\nWu, C. et al. A 1.9-Ga Mélange Along the Northern Margin of the North China Craton: Implications\nfor the Assembly of Columbia Supercontinent. Tectonics. 37, 3610-3646 (2018).\nZhao, G., Cawood, P. A., Wilde, S. A. & Sun, M. Review of global 2.1–1.8 Ga orogens: implications\nfor a pre-Rodinia supercontinent. Earth-Sci. Rev. 59, 125-162 (2002).\nKusky, T., Li, J. & Santosh, M. The Paleoproterozoic North Hebei Orogen: North China craton's\ncollisional suture with the Columbia supercontinent. Gondwana Res. 12, 4-28 (2007).\n4. The manuscript mixed use of full name and abbreviations here and there. For example, North\nChina Craton and NCC; Circa and Ca.; Formation and Fm. (See Lines 52, 110, 123, 127-128,\n140, 158, 201, 206, 317, 344, 661, 631).\nThanks for pointing out this. We have carefully checked this issue. Partially agree.\n(1) North China Craton and NCC: We now use the full name in the whole manuscript.\n(2) When starting a sentence, full spelling (e.g., circa) is required. So ‘Circa’ is correct in Line\n344.\n9\n(3) For the abbreviation of Formation, ‘Fm.’ or ‘Fm’ are widely used. To make it consistent, we\nuse the full name ‘Formation’ in the main text of the whole manuscript but use Fm in figures (to\nsave space).\nLine 123: ‘the protoliths of the formation’ is correct. ‘the formation’ refers particularly to the\n‘Wuzhiling Formation’.\nLine 127-128: Like above. This is correct as well.\nLine 140: We revise ‘Formations’ to ‘formations’.\nLine 158: This is correct.\nLine 201 & 206: We use the full name ‘Formation’ here.\n5. The logic of this manuscript is weak, this work can’t better define the differences and\ncontroversies among the models. The maximum depositional ages of the detrital zircons can’t be\nrepresented the depositional age of the strata, not to mention such old metamorphic strata; The\nage analysis lacks evidence, you can't say pb-loss casually. The authors can’t discuss more\ncontributions about the controversies among the models of lines 260-267 and can’t get this\nconclusion of lines 288-290 without the evidence.\nThanks for the criticism. We address these concerns one by one.\n(1) Tectonic models. As mentioned before, the reviewer should be aware that our main purpose\nis not to resolve the debate on the tectonic models regarding the long-term history of the\nNCC from Archean to Paleoproterozoic but to provide sedimentary and structural\nconstraints on the detailed sedimentary-to-deformation evolution of the Songshan\nforeland and better constrain the distinctive styles of two stages of orogenesis in the\nNeoarchean and Paleoproterozoic. These two stages of orogenesis have not reached a\nconsensus yet, and the styles of orogenesis also require further studies in detail. For example,\nin some models (e.g., Zhao et al., 2005, 2012), there are no detailed constraints on Archean\ncollisional orogenesis. Our data provide new sedimentary evidence for the arc-\nmicrocontinent collision and terrane assembly in the late Archean to the earliest\nPaleoproterozoic. Our new data of rutiles and detrital zircons and structural deformation\nfurther show the different orogenic styles during the late Archean-early Paleoproterozoic (ca.\n2.5 Ga) and middle Paleoproterozoic (ca. 1.9 Ga). The entire evolution of the NCC from\nthe Neoarchean to the Paleoproterozoic is out of the scope of this research and requires\nfurther investigation.\n10\n(2) Maximum depositional ages. Due to the lack of syn-depositional volcanic interlayers, the\ndetrital zircons have been widely used to constrain the maximum depositional ages (MDA)\nof strata ranging from Archean to Phanerozoic in age (e.g., Zi et al., 2022, GCA). For\nPrecambrian zircons, the Pb-loss has a significant influence on the MDA. We have carefully\nexamined the age data and conducted data filtering, and we use conservative methods to\nestimate the MDA.\n(3) Age analysis and Pb loss. We filtered discordant data to preclude the influence of possible\nPb-loss. This is important for Precambrian detrital zircon studies.\nZhao, G., Sun, M., Wilde, S. A. & Li, S. Late Archean to Paleoproterozoic evolution of the North\nChina Craton: key issues revisited. Precambrian Res. 136, 177-202 (2005).\nZhao, G. et al. Amalgamation of the North China Craton: Key issues and discussion. Precambrian\nRes. 222-223, 55-76 (2012).\nZi, J., Rasmussen, B., Muhling, J. R. & Fletcher, I. R. In situ U-Pb and geochemical evidence for\nancient Pb-loss during hydrothermal alteration producing apparent young concordant zircon\ndates in older tuffs. Geochim. Cosmochim. Acta. 320, 324-338 (2022).\n6. I found the conclusions to be somewhat weak - they really do not stress the main contributions\nof the paper. The Conclusions need to be improved.\nWe added a concluding paragraph to highlight and summarize our contribution from this study.\n“In conclusion, this study provides new constraints on the depositional-to-deformational\nevolution of the Paleoproterozoic Songshan foreland –– one of the oldest orogenic\nforelands in the North China Craton, from sedimentary and deformational perspectives.\nImportantly, it underscores the significance of multi-mineral geochronological analysis of\nkey minerals from sedimentary archives in ancient orogenic forelands, which provide clues\nas to how sedimentation and metamorphism responded to changing orogenic style. Our\nresearch has shed new light on changes in tectonic processes during the Archean-\nProterozoic transition and their influence on global biogeochemical cycles, providing an\ninnovative method for investigating the evolution of foreland sedimentary basins.\nAdditionally, our findings offer fresh perspectives on the dynamic interplay between solid\nand surficial Earth processes during the Paleoproterozoic, contributing to a deeper\nunderstanding of our planet’s evolution towards a more habitable environment.”\n11\n7. Comments on the figures:\nFigure 1. Nuna or Columbia??? The timing of supercontinents are right?\nAs replied before, we have addressed this problem about the ‘Nuna’ or ‘Columbia’ (see our\ndetailed response to question 3). In the revised version, we use ‘Columbia’ in the whole\nmanuscript (except for the first appearance) to avoid any debate on the name of the\nPaleoproterozoic supercontinent. The timing and configuration of supercontinents (1.8 Ga) are\nbased on Wan et al., 2020, Science Advances and Wan et al., 2015, Nature Communications.\nWan, B., Windley, B. F., Xiao, W., Feng, J. & Zhang, J. E. Paleoproterozoic high-pressure\nmetamorphism in the northern North China Craton and implications for the Nuna\nsupercontinent. Nat. Commun. 6, 8344 (2015).\nWan, B. et al. Seismological evidence for the earliest global subduction network at 2 Ga ago. Sci.\nAdv. 6, eabc5491 (2020).\nFigures 2-5. the authors discussed the structures, not even providing the nature of faults in the\nFigure 2; the field interpretations seem unclear in the Figures 3-5; the authors should define the\nabbreviations in the figures. No any field data on the foliations and lineations in the Figure 3.\nConfused the COB and TNCO.\nThanks for pointing out this. We improved the figures accordingly.\n(1) In Fig. 2, we provided the nature of faults.\n(2) We added more structural data (foliation, lineation, fold) in Figures 3–5 (now Figs 3, 4, S5).\n(3) All abbreviations have been clarified in the figure captions.\n(4) The COB is used to describe the 2.5–2.47 Ga orogenic belt emphasized by Kusky et al.,\nwhereas the TNCO is used to describe the 1.95–1.8 Ga collisional orogen proposed by Zhao et\nal. They are not in conflict as they represent orogens formed or modified in different periods.\nFigure 6. How does the author distinguish between the detrital/metamorphic ages？\nGood point. Rutile grains from the unmetamorphosed Wufoshan Group are of detrital origin,\nwhile rutile grains from the Songshan Group are dominated by a metamorphic origin (age\nclustering at 2.0–1.8 Ga, n=62), with minor survived detrital rutiles (e.g., 2.50 Ga, n=3) (Table\nS2). The ca. 2.0–1.8 Ga metamorphic rutile in the Songshan Group has distinctive textures and\nFig. 7a–f). We also provided a discussion on this to make it clearer.\n“The timing of metamorphism of the Songshan Group can be constrained by metamorphic\nrutile. The young rutile grains (<2.0 Ga) from the Songshan Group are interpreted to be of\nmetamorphic origin based on the following lines of evidence: 1) the rutile grains exhibit a\nconsistent alignment in the dominant foliation, and have euhedral, subhedral and irregular\nshapes (Fig. 7a–c); 2) the peak ages of 1.95 Ga and 1.87 Ga are markedly younger than\nthose of detrital zircons (Fig. 5b–e); 3) the ZIR temperature of <2.0 Ga rutile grains is low\n(~469–586 °C) and comparable with the Ti-in-biotite temperature (~558–598 °C at 4 kbar)\n(Supplementary Tables 2–3); and 4) subordinate rutile grains with ages exceeding 2.0 Ga\nare inferred to have survived during prolonged Paleoproterozoic (ca. 2.0–1.8 Ga)\nmetamorphism, implying that the peak metamorphic temperature of the Songshan Group\nwas lower than the closure temperature (~600 °C) of rutile in the U–Pb isotope system.”\nFigure 7. Too general and it is difficult to compelling to the readers because many places lack\nevidence, especially the time limits; also confused the COB and TNCO. It seems that the authors\njust want to mix everything together and doesn't clarify geological history very well. This\nmanuscript does not contribute in terms of time constraints, it is too broad.\nThis figure (now Fig. 8) just aims to show the two types of orogenic styles based on our new\nsedimentary, structural, and geochronological evidence, and regional geological data,\nrather than providing a comprehensive history from Neoarchean to Paleoproterozoic. The\ndetailed evolution of the whole NCC from 2.5–2.0 Ga is not the main scope of the paper, and it\nrequires further detailed studies of the magmatic, sedimentary, and metamorphic records across\nthe craton, which cannot be made in a relatively concise paper.\nOverall, we appreciate the critical comments from reviewer #2, which pushed us to better present\nthe work and clarify the novelty of this research.\n13\n=====================================================================\nReviewer #3 (Remarks to the Author):\nHuang and colleagues present a detailed study of the structural history, basin evolution, and\nprovenance of Paleoproterozoic sedimentary rocks in the North China Craton. They integrate\nthese datasets to infer a contrast in the tectonic style of orogenesis and continental assembly in\nthe North China Craton (NCC) between the late Neoarchean and early Paleoproterozoic. The\npaper concludes by discussing the possible influences the purported transition in global tectonic\nregimes across the Archean-Proterozoic may have had on the wider Earth system.\nLinking solid Earth processes and tectonic regimes to the wider Earth system is a highly active\narea of research and of interest to a broad cross section of the scientific community. Multi-\ndisciplinary studies such the one presented in this paper are essential to developing a holistic\nunderstanding of relationship between tectonic processes and surface environments through deep\ntime. The paper by Huang and colleagues takes the novel approach of studying the history of\nforeland sedimentary basins to document changes in tectonic regimes across the Archean-\nProterozoic transition and its impact on global geochemical cycles. The paper is mostly well-\nwritten and is exceptionally and informatively illustrated. In my opinion, this paper would make\nan excellent contribution to Nature Communications. However, I have a number of queries\nregarding the provenance data that should be addressed before publication.\nWe deeply appreciate Reviewer #3 for the positive recommendation and very detailed comments\nregarding the data presentation and discussion, which are impressive and constructive. We have\nimplemented relevant revisions and addressed all concerns accordingly.\nDetrital Rutile evidence\nOne of the main pieces of evidence cited for a change in orogenic style from hot ‘soft’ collision\nin the Neoarchean to hard ‘cold’ collision in the Paleoproterozoic is the near absence of\nNeoarchean detrital rutile in the Songshan Group contrasting with the abundance of\nPaleoproterozoic detrital rutile grains in the Wufoshan Group. This interpretation is consistent\nwith the tendency of rutile to grow in high-P metamorphic rocks, which are more likely to be\nexhumed and eroded into adjacent sedimentary basins in ‘colder’ orogens. Some important\ncaveats to this interpretation are the tendency of rutile to recrystallise to ilmenite or titanite\nduring the greenschist- to amphibole facies of a prograde metamorphic path (e.g., Ashley and\ndiffusion in rutile (~500-600 C = greenschist-amphibolite facies conditions).\nThe fact that the Songshan Group has been metamorphosed to greenschist facies raises the\npossibility that Neoarchean detrital rutile grains were originally present in these sedimentary\nrocks but were subsequently recrystallised or had their U-Pb ages reset during Paleoproterozoic\norogenesis. If this were the case, the reported absence of Neoarchean detrital rutile in the\nSongshan Group could not be attributed to the absence of high-P Neoarchean metamorphic rocks\nin their source region.\nThe authors need to acknowledge these inherent caveats to interpreting rutile U-Pb ages in\nmetamorphic rocks. They should then justify their interpretation that the detrital rutile grains in\nthe Songshan Group are neocrystallised grains that grew during 2.0—1.7 Ga metamorphic event\nrather than being recrystallised or reset older detrital grains. I believe several observations\nalready presented in the paper support the original interpretation made by the authors and should\nbe more explicitly highlighted:\nThank you very much for the constructive comments and solution ideas. We agree that there is\nthe possibility that the Neoarchean detrital rutile grains were originally present in the\nsedimentary rocks and then experienced recrystallization or had their U-Pb ages reset during\nPaleoproterozoic orogenesis. As mentioned by reviewers, several lines of evidence already\nsuggest that this may be not the case for the rutile in the Songshan Group. The rutile texture,\nage, Zr-in-rutile temperature, and existence of > 2.0 Ga rutile grains together imply the older rutile\nhas not been reset by ca. 2.0–1.8 Ga metamorphism. The 2.50 Ga detrital rutiles (n=3) in the\nSongshan Group suggest relatively less high-pressure metamorphism in the Neoarchean. We add\nmore evidence and discussion according to your suggestions to support our original\ninterpretations, with revisions in Lines 222–229 and Lines 313–332 and one-by-one replies for\nthe later comments.\n• Some older detrital rutile grains are preserved in the Songshan Group (Line 172). This suggests\ntemperatures were not high enough during Paleoproterozoic greenschist facies metamorphism to\nreset the U-Pb system of rutile. Given that resetting of the U-Pb system is a function of grain\nsize, this argument could be further supported by demonstrating that the older detrital grains in\nthese samples are of a similar size to the dominant 2.0—1.7 Ga population. The authors report\n15\nthe size of rutile grains in the supplementary files, so quantifying the relationship between grain\nsize and age should be simple.\nThis is a good point. The closure temperature of rutile is ~600 C for rutile grains of ~100 μm\n(Cherniak, 2000, CMP; Pereira and Storey, 2023). The sizes of older rutile grains (~60–130 μm)\nare similar to those grains (~55–130 μm, except for one <50 μm) with ages of 2.0–1.7 Ga from\nthe Songshan Group (see figure below). The few older rutile grains recorded in the Songshan\nGroup suggest that the temperature of Paleoproterozoic (ca. 2.0–1.8 Ga) metamorphism is lower\nthan 600 C of the U-Pb system of rutile. Additionally, the pressure-independent Zr-in-rutile\ngeothermometer results (469–586 C) and Ti-in-mica geothermometer of the schist in the lower\nSongshan Group also support that the metamorphic temperature is not high enough to reset the\nrutile U-Pb system. Phase equilibrium modelling of a quartz mica schist also suggests rutile can\nbe stable over a large P–T condition (Supplementary Fig. S11). Collectively, we suggest that\nthe ca. 2.0–1.8 Ga metamorphism has not reset the U–Pb age of possible older rutile in the\nSongshan Group.\nLength vs. Age of rutile in the Songshan Group. The size of older ones is within the range of ca.\n2.0–1.8 Ga metamorphic rutile.\nCherniak, D. J. Pb diffusion in rutile. Contrib. Mineral. Petrol. 139, 198-207 (2000).\nPereira, I. & Storey, C. D. Detrital rutile: Records of the deep crust, ores and fluids. Lithos. 438-439,\n107010 (2023).\n• Zr-in-Rutile temperatures are low and uniform, which would not be expected if these were\noriginally Neoarchean detrital grains derived from high-T metamorphic rocks elsewhere in the\nNCC. Zr diffusion in rutile is very slow and probably has a closure temperature on the order of\n16\n~700 C. This makes it is unlikely that the Zr concentrations of rutile would have been re-\nequilibrated during greenschist facies metamorphism at 2.0—1.7 Ga. Thus, the authors can rule\nout that the abundant 2.0—1.7 Ga rutile grains in the Songshan Group represent originally ~2.5\nGa detrital grains that have had their U-Pb systematics reset during the 2.0—1.7 Ga event.\nGood point, Zr-in-rutile temperatures of rutiles from the Songshan Group are relatively low and\nuniform (Fig. 7e, Table S2), and the estimated metamorphic temperatures from quartz-mica\nschists by Ti-in-biotite geothermometer are about 558–598 C (at 4 kbar) (Supplementary Note\n4, and Table S3), which do not exceed the closure temperature 700 C of Zr diffusion in rutile.\nNew Fig. 7e–f shows Zr-in-rutile temperatures of the Songshan and Wufoshan groups. The\nSongshan rutile is mostly of metamorphic origin (<2.0 Ga) and records lower uniform\ntemperatures. Two ca. 2.5 Ga detrital rutile grains have higher temperatures (~657 C).\n• The samples appear to be compositionally (super-)mature Qtz-rich rocks that are presumably\nCa- and Fe-poor. Ca- and Fe-poor bulk compositions would not favour conversion of detrital\nrutile grains to ilmenite or titanite during prograde metamorphism. Thus, the Songshan Group\nhas a favourable composition to preserve older detrital rutile grains, if they were present (and as\nabove, the U-Pb data indicates that some older ages are indeed preserved).\nThis is true, the quartzite and quartz-mica schist samples from the Songshan Group are\ncompositionally poor in calcium and iron. The quartzite consists mainly of quartz and minor\nmica, and the quartz-mica schist consists of mica and quartz, with minor feldspar, magnetite,\nzircon and rutile (Fig. S3). We carefully checked the petrographic characteristics of the samples\nfrom the Songshan Group under SEM and EDS and didn’t observe ilmenite or titanite in these\nsamples. Thus, we suggest that the few older rutile grains have not been transformed into\nilmenite or titanite during prograde or retrograde metamorphism.\n17\n• The authors note that rutile in Songshan Group are aligned with dominant foliation as evidence\nof metamorphic origin. I agree, but it would be nice to show a photomicrograph in the main body\nof the manuscript demonstrating this textural evidence.\nNew Fig. 7a–d shows the in-situ rutile textures and different shapes between the Songshan and\nWufoshan groups.\nGood suggestion. We added several photomicrographs (Fig. 7a–d) to show the textural evidence\nthat supports rutile grains are of metamorphic origin in the main text. Therefore, based on the\nabove evidence, we interpret that the majority of rutile grains in the Songshan Group are\nneocrystallised grains during 2.0–1.7 Ga. The striking difference between the scarcity of\nNeoarchean detrital rutile in the Songshan Group and the abundance of Paleoproterozoic detrital\nrutile grains in the Wufoshan Group can support the inference that a change in metamorphic and\norogenic styles from the Neoarchean to the Paleoproterozoic.\nDetrital zircon evidence\nThe authors suggest that only the Wufoshan Group contains detrital zircons derived from\nmetamorphic sources, suggesting that only the Paleoproterozoic orogenic event produced a\n18\nsufficient volume of thickened orogenic crust to be sampled by the sedimentary archive.\nThe only evidence supporting this interpretation that is presented in the main body of the paper is\nthat ‘…only the Wufoshan Group contains zircons with numerous core-rim structures…’ (lines\n286—287). However, from the CL images of detrital zircon grains from the Songshan Group\npresented in the supplementary material (Fig. S5), I can see several grains that apparently have\nsecondary overgrowths or zones that truncate oscillatory-zoned core domains (e.g., grains 13, 9,\n2 on Panel A, grains 14 and 16 on panel B, grain 3 on panel C, grains 17 and 32 on panel E,\ngrain 2 and 26 on Panel F). The argument that core-rim structures are more common in detrital\nzircons from the Wufoshan Group would be more compelling if the authors could quantify how\ncommon these textures are in both the Songshan and Wufoshan groups (i.e. what % of grains\nhave core-rim structures in each group?).\nThank you for the insightful comment and suggestion.\nYes, most zircon grains from the samples in the lower Songshan Group have textures of\nmagmatic origin, with minor zircons having a very thin rim, which might be metamorphic\novergrowth (either detrital metamorphic rim or post-depositional recrystallization). However, the\npercentage is relatively low, and the rim is too thin to be dated (Supplementary Fig. 6a–f).\nWe counted all zircon grains (randomly mounted) and evaluated the proportions of grains\nwith core–rim textures in every sample. The statistical results suggest that the percentage of\nzircons with core–rim structures from the Songshan group is ~6%, and the percentage of\nzircons with core–rim structures from the Wufoshan group is ~21% (this didn’t include\nhomogenous metamorphic zircons without rim).\nIn addition, most zircons from the Songshan Group show oscillatory zoning as described in the\nSupplementary Note and shown in Fig. S6, suggesting that they are mainly derived from\nmagmatic sources. Therefore, we suggest that the Wufoshan Group contains detrital zircons from\na metamorphic source.\nWe provided detailed information on different samples as follows.\n Sample from the Wufoshan Group (~21% zircons with metamorphic rims):\nSample 20DF03: total zircons (n=212), grains with core-rim structures (n=45), ~21%;\nNote that metamorphic zircons with homogenous banded or broad zoning (e.g., some\n19\nof them with HREE-depleted characteristics, Fig S8a-b) was not counted here. The\npercentage of overall metamorphic zircon should be higher than 21%.\n Samples from the Songshan Group (~5.6% zircons with thin bright rims):\nSample 21SS25: total zircons (n=224), grains with core-rim structures (n=0), 0%;\nSample 20SS05: total zircons (n=220), grains with core-rim structures (n=9), ~4%;\nSample 20SS06: total zircons (n=212), grains with core-rim structures (n=7), ~3%;\nSample 20SS01: total zircons (n=211), grains with core-rim structures (n=20), ~9%;\nSample 20SS07: total zircons (n=212), grains with core-rim structures (n=17), ~8%;\nSample 20SS09: total zircons (n=121), grains with core-rim structures (n=14), 12%;\nCollectively, 67 grains have thin rims among 1200 (randomly mounted) counted zircon\ngrains = 5.57% (typical zircons with rims are shown in Fig. S6a–f).\nWe incorporated relevant information into Supplementary Note 2.1.1 when describing the\ngeochronological results and added this information in the main text (e.g., Lines 323-324).\nThe authors also cite Fig. S9 as containing additional evidence for abundant metamorphic-\nderived zircons in the Wufoshan Group (lines 286—287) but do discuss the significance of the\ndata presented in this supplementary figure. Fig S9 summarises REE patterns for zircons from\nthe Wufoshan Group and shows that some grains have HREE-depleted signatures, which are\ntypical of zircon that has co-crystallised with garnet, potentially indicating high-P\nmetamorphism. However, these REE-patterns are not tied to the corresponding U-Pb age of the\ngrains. Furthermore, the HREE-depleted measurements apparently come from the cores of zircon\ngrains that are surrounded by metamorphic rims, which the authors appear link to the main\nPaleoproterozoic metamorphic event. Based on this data, I have two queries:\n(1) How can the authors be certain these HREE-depleted metamorphic zircons aren’t pre-2.0 Ga\ngrains and hence actually provide evidence for high-P metamorphism related to the earlier\n(Neoarchean) orogenic event(s). I note from Fig. 6F that the Wufoshan Group contains numerous\npre-2.0 Ga detrital grains. If the authors could demonstrate that all of the HREE-depleted zircons\nin the Wufoshan Group are ~1.7-2.0 Ga, it would strengthen the interpretation that the\nPaleoproterozoic metamorphic event was characterised by higher pressure metamorphism\ncompared to earlier orogenic events.\nThank you for this insightful comment and suggestion. We added more CL images showing the\nstructure of zircons with HREE-depleted characteristics (low Lu/Gy ratios, Fig. S8 below) and\nN\nlabelled the ages and Th/U and (Lu/Dy) ratios of these zircons (see new Fig. 6 below). Except\nN\n20\nfor one older metamorphic zircon with an age of 2.15 Ga, the ages of the rest zircons are\nconcentrated at ca. 2.0–1.9 Ga. Circa 2.15 Ga metamorphism is reported by Trap et al. (2012)\nand Wang et al. (2023) from the central orogen of the NCC, and 2.0–1.8 Ga metamorphism is\nwidespread in this orogen. As we discussed in the paper, the HREE-depleted signature suggests\nthat these zircon grains are co-crystallized with garnet, and may have undergone HP\nmetamorphism (Zhu et al., 2021, EPSL), indicating that these zircon grains in the Wufoshan\nGroup recorded the Paleoproterozoic metamorphism.\nUpdated Supplementary Figure S8 shows the CL images of some typical zircons in the\nWufoshan Group, and chondrite normalized REE patterns of zircon from the Wufoshan,\nSongshan and Dengfeng.\nzircon with age. Except for two Archean grains with MGS, others are early Proterozoic in age\n(dominantly 2.0–1.9 Ga).\n(2) I am curious as to why similar detrital zircon REE data has not been presented from the\nSongshan Group. A comparison of time-constrained REE data from detrital zircons from both\nthe Wufoshan and Songshan groups would make for a much more balanced comparison of the\nmetamorphic style of Neoarchean vs. Paleoproterozoic orogenesis based on detrital zircon record\n(i.e., demonstrate that Neoarchean detrital zircon populations lack HREE-depleted signatures,\nwhereas Paleoproterozoic zircon populations do contain them).\n(Fig. S8) and added a figure in the main text (Fig. 6) to show the REE data [Lu and (Lu/Dy) that\nN\nsignify the metamorphic garnet signature, MGS] of detrital zircons from the Wufoshan Group,\nSongshan Group and Dengfeng Complex, along with REE data sets from the global detrital\nzircons as a background for comparison.\nZircons from the Songshan and Wufoshan groups have only three Neoarchean analyses with an\nHREE-depleted signature, and the HREE-depleted analyses are dominated by Paleoproterozoic\nages (ca. 2.0–1.8 Ga), supporting our interpretation about the different styles of metamorphism\n(and orogenic styles). This is also consistent with the distribution of MGS in the global detrital\nzircon dataset (Fig. 6d).\nMinor comments (Line-by-line)\nLine 1 (title): I would remove ‘dramatic’ from the title. Much of the evidence for a change in\norogenic style in the NCC is from models and datasets beyond the foreland basin deposits that\nthis paper focuses on. I think the evidence from the sedimentary record is more subtle but\ncompelling nonetheless (as is always the case for reconstructing orogenic histories from\nsedimentary rocks).\nThanks, good point. We revised the title and deleted the ‘dramatic’.\nLine 53—54: Somewhat redundant to describe an ‘Alpine-style’ fold-and-thrust belt associated\nwith a ‘Himalayan-style’ collisional orogeny. Describing it as a fold-and-thrust belt developed\nduring a Himalayan- (or Alpine) style collision would suffice.\nThanks for this good point. We have changed it to ‘Himalayan-style’.\nLine 70: Replace ‘loosely’ with ‘incompletely’ documented.\nDone.\nLine 113: The clasts (not ‘gravels’) in the conglomerate are aligned with the tectonic foliation.\nRevised.\nthat contain dusted rims and quartz overgrowths.\nThanks. Revised.\nLine 216: Typo: ‘provenances’ should be provenance.\nRevised.\nLine 217: Typo: ‘filtration’ should be filtering.\nRevised.\nLine 276: ‘…could be linked to a secular change of orogenesis’. This clause isn’t needed here.\nThe point being made is that rutile forms in high-pressure metamorphic rocks. This is true\nregardless of when high-pressure rocks first appeared in the geological record (which is more\nrelevant when this point is discussed later in the paper).\nAgree, we deleted this.\nLine 278: Typo: ‘event’ should be events.\nRevised.\nLine 282: Typo: ‘metamorphic origins’ should be metamorphic origin.\nRevised.\nLine 288: ‘indicate’ should be replaced with ‘….are interpreted to reflect….’ or ‘record’.\nGood point. Revised.\nLine 295: unclear what is meant by ‘….where the largest accretion and crustal growth occurred’.\nLargest accretion and growth compared to what? The local geology or the globally? Or do you\nmean Altaid-style orogens are the sites of significant crustal accretion and growth?\nThanks, and yes, the Altaids is the largest Phanerozoic accretionary orogen, where the juvenile\ncrust was accreted. We revised this sentence to make it clearer.\nLine 299: final sentence of this paragraph is vague. Do you mean rutile and low-Lu and low-\nLu/Dy zircons are rare at this time in the global detrital record? If you want to make this point,\nyou need to explain the significance of low-Lu and low-Lu/Dy zircons.\nThanks for this good comment. We revised the sentence and added a relevant reference to\nindicate that the low-Lu and low-Lu/Gd zircons can signify the garnet signature that formed\ngenerally >1.2 GPa (Zhu et al., 2022, EPSL). We also supplemented a figure (Fig. 6) to show\nthis.\nZhu, Z., Campbell, I. H., Allen, C. M., Brocks, J. J. & Chen, B. The temporal distribution of Earth's\nsupermountains and their potential link to the rise of atmospheric oxygen and biological\nevolution. Earth Planet. Sci. Lett. 580, 117391 (2022).\nLine 305: I’m not convinced that high-pressure granulites (and to some extent eclogites) provide\nevidence of ‘cold subduction’. Granulites aren’t common in ‘cold’ subduction zones and perhaps\nonly Lawsonite eclogites provide compelling evidence for ‘cold’ subduction. If there are\nmetamorphic rocks that do record low T/P thermal gradients in the NCC, these should be\nhighlighted.\nThank you for this good suggestion. Xu et al. (2018, Nature Communications) reported low-\ntemperature and high-pressure eclogite xenoliths (~560 C/2.6 GPa, ca. 1.85 Ga) from\ncarbonatite dyke, which has been regarded as an important piece of evidence for low T/P thermal\ngradients. We have added this reference.\nXu, C. et al. Cold deep subduction recorded by remnants of a Paleoproterozoic carbonated slab.\nNat. Commun. 9, 2790 (2018).\nLine 317—319: As written it this sentence implies that only the tectonic events in the NCC\ninfluenced the wider Earth system. I think the authors mean that the changes recorded in the\nNCC are typical of those preserved in many early Paleoproterozoic terranes, suggesting a global\nlink between a transition in tectonic regime and surficial environments. As such, it would be\nhelpful to cite some other examples where similar Archean-Paleoproterozoic tectonic transitions\nare preserved in the structural, sedimentary, magmatic record (e.g., Western Australia, North\nAmerica, South Africa…).\nGood point, North China records the cratonization at 2.5-2.45 Ga due to collision between arcs\nand micro-continent blocks. Following this, widespread clastic rocks were developed along\nforeland and cratonic margins. The record of sedimentation increased in most cratons worldwide,\nsuch as in India, North America, Western Australia, and South Africa (e.g., Cawood et al., 2018\nand references therein). We revised this sentence and added relevant references.\nCawood, P. A. et al. Geological archive of the onset of plate tectonics. Phil. Trans. R. Soc. A. 376,\n20170405 (2018).\nLine 319—320: Are you saying this style of late Archean cratonisation is typical of the NCC or\nall cratons? If the latter, need to support with references.\nThank you for this good suggestion. The Neoarchean cratonization should have been widespread\nin most cratons, as there were many Neoarchean to early Paleoproterozoic clastic sedimentary\nrocks overlain the Archean basement rocks. We added relevant references from other cratons\nhere.\nLine 325: Typo: ‘Nutrition’ should be nutrients. For those not familiar with biochemical cycles,\nit would be useful to elaborate on what these nutrients actually are and how they form an\nimportant component of orogenic rocks.\nThank you. We corrected the typo, and added these key elements (e.g., P, Ca, Mg), which are the\nkey nutrients thought to limit primary productivity on geological timescales.\nLine 334—336: Might be helpful to remind the readers that these are quartz-rich clastic rocks,\nwhich provides evidence that the more labile minerals in their source TTGs/greenstones were\nindeed destroyed during weathering.\nThank you for this good suggestion. We added this point.\nappropriate here.\nAgree. We also cited this nice review in Introduction section.\nLine 358: ‘higher peak metamorphic pressures from minerals or increased high-pressure rock\nrecord’. This is vague, aren’t these the same thing? i.e., high-pressure rocks are defined by\nhaving high-pressure minerals.\nThanks for this good comment. We revised this sentence accordingly.\nLine 362—367: Unclear if this is a general statement about all orogens or just the study area.\nWe revised this sentence. This statement about the orogenic characteristics can be applicable to\nthe majority of global Paleoproterozoic orogens, as more and more high-pressure rocks have\nbeen recognized (e.g., Weller and St-Onge, 2017, NG; Brown and Johnson, 2018 for a\nsummary). Some key features such as the foreland compressional deformation documented in\nthis study are highlighted.\nWeller, O. M. & St-Onge, M. R. Record of modern-style plate tectonics in the Palaeoproterozoic\nTrans-Hudson orogen. Nat. Geosci. 10, 305-311 (2017).\nBrown, M. & Johnson, T. Secular change in metamorphism and the onset of global plate tectonics.\nAm. Miner. 103, 181-196 (2018).\nLine 368—377: The concluding paragraph linking the stabilisation of continents to the boring\nbillion and the appearances of eukaryotes is essentially a throw-away line. In the context of this\npaper, the link between continental stabilisation, the boring billion, and eukaryote evolution is\nnot clear. Is it to do with ocean chemistry? tectonics? What new insights on these topics does this\npaper make? A stronger finish would be to reinforce the sedimentary response to changing\norogenic styles, which is really what this paper does a nice job of doing.\nThank you for the good comment and suggestion. The original intention in the last paragraph\nwas to emphasize that the collapse of the Paleoproterozoic Himalayan-style collisional orogens\nled to continental stabilisation and sedimentation such as those in the Wufoshan Group, which\n27\ndeposited along orogenic and cratonic margin or interior. We shortened this paragraph and added\nsome references.\nWe add a concluding paragraph to highlight the sedimentary response to the orogenic styles as\nbelow:\n“In conclusion, this study provides new constraints on the depositional-to-deformational\nevolution of the Paleoproterozoic Songshan foreland –– one of the oldest orogenic\nforelands in the North China Craton, from sedimentary and deformational perspectives.\nImportantly, it underscores the significance of multi-mineral geochronological analysis of\nkey minerals from sedimentary archives in ancient orogenic forelands, which provide clues\nas to how sedimentation and metamorphism responded to changing orogenic style. Our\nresearch has shed new light on changes in tectonic processes during the Archean-\nProterozoic transition and their influence on global biogeochemical cycles, providing an\ninnovative method for investigating the evolution of foreland sedimentary basins.\nAdditionally, our findings offer fresh perspectives on the dynamic interplay between solid\nand surficial Earth processes during the Paleoproterozoic, contributing to a deeper\nunderstanding of our planet’s evolution towards a more habitable environment.\n”\nLine 379: (Methods). No data for reference materials is presented in the supplementary material.\nIt is stated that ‘all ages are consistent with recommended values’ but the original data for the\nreference materials must be included so their veracity can be assessed independently.\nThank you for this important comment, we added the standard information and references\naccordingly.\nGeneral comments on grammar\n• The definitive article (the) is used incorrectly in several places throughout the manuscript. I\nencourage the native English-speaking co-authors or journal type editors to revise.\nThank you. we carefully checked the grammar issue.\n• A more pedantic point, but the use of forward slashes (/) obscures the intended meaning of the\n28\ntext in several places. It’s not clear if the forward slash means ‘or’, ‘and’, or is taking the place of\na hyphen. For example, arc/micro-continent collision. Is this describing a collision between an\narc and a microcontinent (arc-microcontinent collision), or is it indicating there were multiple\ncollisions, some involving arcs and microcontinents, others involving only arcs or only\nmicrocontinents? I suggest replacing ‘/’ with ‘and’ or with ‘or’ for clarity.\nGood point. We have replaced the forward slashes with the ‘and’ ‘or’ or ‘hyphen’ in most places.\nWe are deeply appreciative of the comprehensive and constructive comments and suggestions\nprovided by Reviewer #3. These inputs have played a pivotal role in enhancing the quality of our\nmanuscript.\n29"}, "author_response": ""}, {"round": 2, "reviewer_comments": {"reviewer_1": "I have carefully read through the detailed responses to reviewers and the revised manuscript provided\nby the authors. I think they have done a thorough job in responding to the reviewers' comments, with\nan excellent level of detail. It is my view that the reviewers' questions have been appropriately\nanswered, and their comments and suggestions, addressed and incorporated. I think the manuscript is\nnow ready for publication in NC. I would like to thank the authors for the thoughtful and detailed way in\nwhich they responded to the reviewers' concerns.", "reviewer_2": "1. I don’t think the authors seriously responded to the comments and didn't revised the paper to\naddress the concerns; the authors tried to avoid the main issues.\n2. Again, one of the main problems is that this work in this paper is not novel, similar concepts and have\nbeen discussed in the previous publications. Therefore, I do not think the paper meets the standard and\nlevel of the journal of Nature Communication. The paper is more suitable for publication in journal of\nPrecambrian Research, Tectonics and et al.\n3. Too many papers showed the regional evolution models of the North China Craton during\nNeoarchean and Paleoproterozoic similar to this paper, whether it's once or twice collision and when.\nThere's no need to list them all here. This study contributes nothing new among these models and don't\nclarify these controversies.\n4. Typos and weird expression here and there.\nI strongly reject the publication of this revised manuscript in Nature Communications.", "reviewer_3": "The authors have done a thorough job of revising this manuscript. All of my comments on the original\nmanuscript have been clearly and comprehensively addressed.\nIt is particularly satisfying to see that the authors have presented new observations and analysis in\naddressing my comments, which further strengthen what was already an excellent study.\nThis is an interesting and engaging piece of work that will make a valuable contribution to Nature\nCommunications. I recommend the revised manuscript be accepted."}, "author_response": "RESPONSE TO REVIEWERS' COMMENTS (REPLY IN BLUE)\nReviewer #1 (Remarks to the Author):\nI have carefully read through the detailed responses to reviewers and the revised manuscript provided\nby the authors. I think they have done a thorough job in responding to the reviewers' comments, with an\nexcellent level of detail. It is my view that the reviewers' questions have been appropriately answered,\nand their comments and suggestions, addressed and incorporated. I think the manuscript is now ready\nfor publication in NC. I would like to thank the authors for the thoughtful and detailed way in which they\nresponded to the reviewers' concerns.\nWe deeply appreciate the Reviewer #1 for the constructive comments and positive recommendation\nduring the past two rounds of reviews.\nReviewer #2 (Remarks to the Author):\n. I don’t think the authors seriously responded to the comments and didn't revised the paper to address\nthe concerns; the authors tried to avoid the main issues.\nWe have carefully revised the manuscript and addressed the concerns from all reviewers in the first\nrevision, as summarized by other reviewers. In particular, we have addressed all concerns and issues\nraised by this reviewer in the main text and response letter in the first revision, with emphasizing the aim\nand key innovation points of this manuscript. No issue has been avoided.\n2. Again, one of the main problems is that this work in this paper is not novel, similar concepts and have\nbeen discussed in the previous publications. Therefore, I do not think the paper meets the standard and\nlevel of the journal of Nature Communication. The paper is more suitable for publication in journal of\nPrecambrian Research, Tectonics and et al.\nIn this study, we use the integrated field, structural and multi-mineral geochronological data sets from the\none of oldest foreland successions in the North China Craton to better constrain the distinctive styles of\ntwo stages of orogenesis. The detrital zircon U-Pb data constrain the maximum depositional age of the\nsuccession. The structural data reveal the Alpine style fold-and-thrust structures. The combined usage of\ndetrital rutile and zircon from different sedimentary successions (Songshan vs. Wufoshan groups)\nprovides new clues and insights into the metamorphic patterns of the source regions, thus reflecting the\ndifferent orogenic styles. We further link the change of orogenesis with silicate weathering and near-\nsurface environment change.\nThe reviewer seems ignore the new perspectives (e.g., sedimentary and structural) and methods (e.g.,\nmulti-mineral geochronology, big-data) on the general scientific questions (e.g., the change of orogenic\nand plate tectonic styles, interplay between solid and surface systems) presented in this study.\n3. Too many papers showed the regional evolution models of the North China Craton during Neoarchean\nand Paleoproterozoic similar to this paper, whether it's once or twice collision and when. There's no need\nto list them all here. This study contributes nothing new among these models and don't clarify these\ncontroversies.\nAs we replied before, there are two episodes of tectono-thermal events documented in the North China\nCraton, which have been linked with growth and assembly of the craton, providing a unique natural\nlaboratory to explore the styles of orogenesis and plate tectonics.\nExcept for the general implications, our results contribute to at least three aspects on the evolution of the\nNorth China Craton: 1) constraints on the age span of deposition of the Songshan Group, providing\nfurther sedimentary evidence for the Altaid-style terrane assembly and arc-microcontinent collision in the\nend-Archean. 2) determination of Paleoproterozoic metamorphism and Alpine-style deformation in the\nDengfeng-Songshan segment, indicating this region underwent overprinting during the Paleoproterozoic\nHimalayan-style orogenesis. 3) multi-mineral geochronology and detrital rutile and zircon reveal different\nmetamorphic patterns in the Neoarchean and Paleoproterozoic, consistent with distinctive orogenic\nstyles.\nThese new findings suggest that the tectonic evolution of the North China Craton is very complex, and\navailable popular tectonic models may need further improvement, which, however, is not the focus of this\nmanuscript where we concentrate on the orogenic styles.\n4. Typos and weird expression here and there.\nThis is an ambiguous comment. The text has been carefully checked by all coauthors (including three\nnative English speakers) in the previous version. Before submission of this new version, we also\ncarefully checked the language again.\nI strongly reject the publication of this revised manuscript in Nature Communications.\nWe thank Reviewer #2 for his/her critical comments during past two rounds of review, which have been\nuseful for us to clarify and improve the work.\nReviewer #3 (Remarks to the Author):\nThe authors have done a thorough job of revising this manuscript. All of my comments on the original\nmanuscript have been clearly and comprehensively addressed.\nIt is particularly satisfying to see that the authors have presented new observations and analysis in\naddressing my comments, which further strengthen what was already an excellent study.\nThis is an interesting and engaging piece of work that will make a valuable contribution to Nature\nCommunications. I recommend the revised manuscript be accepted.\nWe deeply appreciate Reviewer #3 for the constructive comments and positive recommendations during\nthe past two rounds of reviews. The comments have been very helpful for us to clarify and improve the\nquality of the manuscript."}]

Decision letter