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The evolution of the Taiwan orogen, an active arc–continent collision zone between the North Luzon Arc (NLA) and the Eurasian continent, is recorded in arc volcanic and sedimentary rocks from the Taiyuan retro‐foredeep basin of the Coastal Range, eastern Taiwan. Arc volcanism in the northern NLA experienced a magmatic culmination at 9–7 Ma and a cessation at 5.3–4.3 Ma, based on new U‐Pb zircon ages. Young zircon U‐Pb ages (1.74, 1.58, and <1.2 Ma) and low Hf isotope signatures also indicate that three biotite‐bearing lapilli tuff layers deposited in the retro‐foredeep basin are associated with eruptions of the Lutao volcano in the southern NLA. NLA volcanism terminated progressively from ∼5.3 to <1.2 Ma in response to a southward‐propagating collision zone that followed the uplift of the orogenic wedge by <3 myr. The detrital zircon U‐Pb age spectra suggest no significant shift in provenance during the Plio‐Pleistocene period and indicate that the synorogenic sediments in the Taiyuan Basin were mainly derived from the Yuli Belt, a Miocene accretionary complex in the eastern Taiwan orogen. The accumulation rate of synorogenic deposits varies from 0.53 to 5.14 km/myr, with an abrupt increase at ∼2 Ma. This new rate is higher than the previously proposed rates and that of the pro‐foreland basin to the west, suggesting asymmetric and rapid uplift of the Taiwan orogen. Plain Language Summary: Taiwan was formed by the northwestward convergence of the North Luzon Arc (NLA) with the Eurasian continental margin. Most of the uppermost parts of the arc volcanoes and orogens have been intensely eroded; nevertheless, their detritus is well preserved in the Taiyuan Basin in the southern Coastal Range, eastern Taiwan. In this study, zircons separated from remnant arc volcanic and sedimentary sequences are dated by an in situ U‐Pb method to offer temporal constraints and provide insight into the arc‐continental collision evolution in Taiwan. The latest ages from the NLA volcanoes reveal a southward cessation of magmatism from ∼5.3 to <1.2 Ma, which is consistent with an oblique collision. Detritus from the Yuli Belt, a Miocene accretionary prism in the eastern Taiwan orogen, started to fill the Taiyuan Basin beginning at <4.3 Ma. Meanwhile, three embedded tuff layers dated at 1.74, 1.58, and <1.2 Ma indicate eruptions associated with Lutao, an offshore NLA volcanic islet, and suggest an abrupt increase in the deposition rate at ∼2 Ma, corresponding to rapid and extensive exhumation of the Taiwan orogen. Key Points: New zircon U‐Pb ages confirm the history of the volcanic arc and retro‐foredeep sediments and their linkages to the nearby Taiwan orogenThe previously proposed shift in clastic composition of the retro‐foredeep sediments is interpreted as an unroofing record of the Yuli BeltOur zircon ages confirm the abrupt increase in the deposition rate of retro‐foredeep basin infilling from 0.53 to 5.14 km/myr at ∼2 Ma [ABSTRACT FROM AUTHOR]

Lake Baikal, the largest freshwater reservoir on Earth (~600 × 30 km in size and up to 1.6 km in depth), has more than 300 contributing rivers but only one N-trending outflow – River Angara. In the Pliocene or Pleistocene, another N-trending outflow operated through the Palaeo-Manzurka to Lena. Provenance analysis using U–Pb dating of detrital zircons from the Palaeo-Manzurka sediments demonstrates that the dominant source of the zircons was the lake deposits, while the contribution of zircons from local bedrocks was limited to about 8% only. Looking for an explanation of this, we propose a hypothesis that formation of the Palaeo-Manzurka sediments took place in association with a catastrophic mega-landslide (~15 × 3 km) into the lake and the resulting mega-tsunami flooding. [ABSTRACT FROM PUBLISHER]

Nephrite in the Fengtien area of the eastern part of the Central Mountain Range, Taiwan, is associated with antigorite-serpentinite within the Yuli belt, a late Cenozoic subduction–accretionary complex related to the eastward subduction of the South China Sea plate forming the Luzon arc. Diopsidite and clinozoisite rock are two other metasomatic components accompanying nephrite between serpentinites and the greenschist-facies country rock (carbonaceous material-)quartz-mica schist. Detrital zircons were separated from one clinozoisite rock sample, formed through metasomatic replacement after mica-quartz schist at temperatures of 320–420°C or slightly lower, which is lower than the metamorphic temperature conditions of the Yuli belt. Most of the detrital zircons have thin zircon rims less than 15–20 μm wide. These zircon rims, considered as newly formed during metasomatism leading to nephrite/diopsidite/clinozoisite rock formation, were dated by a high lateral resolution secondary ion mass spectrometer (CAMECA NanoSIMS NS50). The resulting238U/206Pb-204Pb/206Pb inverse isochron gave an age of 3.3 ± 1.7 Ma. The collision of the Eurasian continental margin with the Luzon arc has been suggested to have begun at ca. 6.5 Ma in the Taiwan area. The nephrite formation processes therefore clearly post-dated South China Sea plate subduction. The present date, substantiated by the metamorphic and metasomatic temperature information, demonstrates that the fluid–rock interaction forming Fengtien nephrite would have taken place during a Barrovian-type metamorphic overprint resulting from arc-continent collision, leading to the exhumation of the Yuli belt. This conclusion on nephrite formation with regard to regional tectonics can serve as a working model for future studies on other nephrite deposits with similar occurrences, mostly embedded within Mesozoic or older subduction-accretionary complexes. The Fengtien nephrite deposit is therefore the youngest one of its kind exposed on Earth’s surface. [ABSTRACT FROM PUBLISHER]

Abstract: Zircons from two Myanmar jadeitite samples were separated for texture, mineral inclusion, U–Pb dating and trace element composition analyses. Three types of zircons, with respect to U–Pb isotope system, were recognized. Type I zircons are inherited ones, yielding an igneous protolith age of 160±1Ma; Type II zircons are metasomatic/hydrothermal ones, giving a (minimum) jadeitite formation age of 77±3Ma; and Type III zircons are incompletely recrystallized ones, with non-coherent and geologically meaningless ages from 153 to 105Ma. These Myanmar jadeitites would therefore have formed through whole-sale metasomatic replacement processes. Compared with Type I zircons, Type II zircons show typical metasomatic/hydrothermal geochemical signatures, with low Th/U ratio (<0.1), small Ce anomaly (Ce/Ce*=<5) and low ΣREE content (40–115ppm). Type III zircons, however, commonly have the above geochemical signatures straddle in between Type I and Type II zircons. It is shown that the resetting rates of various trace element compositions and U–Pb isotope system of inherited zircons are not coupled “in phase” in response to zircon recrystallization during jadeitite formation. The observed abnormally low Th/U ratio and small Ce anomaly of some Type I zircons, as well as the lack of negative Eu anomaly of all Type I zircons, should be suspected to be of secondary origin. In extreme cases, incompletely recrystallized zircons may show typical metasomatic/hydrothermal geochemical signatures, but leave U–Pb isotope system partially reset or even largely unchanged. Such zircons easily lead to incorrect age interpretation, and hence erroneous geological implication. The Myanmar jadeitites, based on the present study, might have formed during the Late Cretaceous subduction before the beginning of India–Asia continental collision at Paleocene. Previously proposed Late Jurassic ages for Myanmar jadeitites are suggested as results rooted on data retrieved from incompletely recrystallized inherited zircons. [Copyright &y& Elsevier]

Highlights • Metasedimentary sequences of the enigmatic South Muya block (southern Siberia) were studied for geochemistry and U-Pb-Hf-Nd isotopes. • The precursor sediments were derived from the Tonian continental arc with at least Paleoproterozoic basement and were not related to evolution of the Paleoasian Ocean. • The provenance of the Muya terrane sediments show strong affinity to Gondwana-related continents (South China). • Two high-grade accretion-related metamorphic stages (764–754 Ma and 622–608 Ma) are distinguished based on zircon U-Pb-Hf systematics. Abstract High-grade metasedimentary rocks of the South Muya block (Baikal-Muya Foldbelt) have been studied with respect to whole-rock elemental and Nd isotopic compositions, as well as the U-Pb and Lu-Hf systematics of detrital zircon and in-situ grown metamorphic grains in order to reveal the initial source provenance for sedimentation and the age of major metamorphic modification. Based predominantly on trace-elemental compositions, the sedimentary protolith is most likely a poorly sorted and immature greywacke, such as those formed in island arc or active continental margin settings. The island arc-related chemical signature coupled with zircon U-Pb age data supports a Neoproterozoic (>760 Ma) sedimentation age, whereas Nd-Hf isotope data of precursor sediments are linked to a relatively immature Tonian (∼940–780 Ma) continental arc involving Paleoproterozoic crustal basement. The limited provenance information and metamorphic history of the Muya block suggests it was exotic to Siberia and originally related to another continent, e.g. – subduction-accretion complexes of South China. The polyphase metasediments experienced high-grade metamorphism in the Tonian during the 764–754 Ma arc accretion to an enigmatic continental block and then in the Ediacaran during the 622–608 Ma accretion of the Baikal-Muya belt to the arc situated at the southern Siberia margin. Metamorphic overprinting during the introduction of supracrustal rocks to deeper-crustal levels led to protracted recrystallization of primary igneous zircon population and growth of new granulite-facies grains that did not involve notable juvenile input. Tonian sedimentary provenance and two metamorphic events suggest a protracted evolution for the Baikal-Muya belt associated with the formation of precursor complexes beyond the southern margin of Siberia and their later accretion to Late Cryogenian – Ediacarian arc complexes of the southern Siberian, which proceeded only after the opening of the Paleoasian Ocean (670–630 Ma). [ABSTRACT FROM AUTHOR]

Abstract: This study reports zircon LA-ICPMS U–Pb ages of 50 igneous rock samples from the Urumieh–Dokhtar magmatic arc (UDMA) and Sanandaj–Sirjan structural zone (SSZ) in Iran. These results, together with literatures and our unpublished age data, better delineate the magmatic evolution related to the Neotethyan subduction and subsequent Zagros orogeny that resulted from the Arabia–Eurasia collision. Subduction-related magmatism was active during Jurassic time, as evidenced by the presence of widespread I-type granitoids from the Middle to Late Jurassic (176–144Ma) in the SSZ. After a protracted magmatic quiescence in the Early Cretaceous, igneous activity renewed inland in the UDMA from which we identify Late Cretaceous granitoids (81–72Ma) in Jiroft and Bazman areas, the southeastern segment of the UDMA. The UDMA volcanism was most active and widespread during the Eocene and Oligocene (55–25Ma), much longer lasting than previously thought as just an Eocene pulse. Such a prolonged igneous “flare-up” event in the UDMA can be correlated to Armenia where coeval calc-alkaline rocks are common. The UDMA magmatism ceased progressively from northwest to southeast, with magmatic activities ending the Early Miocene (ca. 22Ma) in Meghri, the Middle Miocene (ca. 16Ma) in Kashan and the Late Miocene (ca. 10–6Ma) in Anar, respectively. The southeastward magmatic cessation is consistent with the notion of oblique and diachronous collision between Arabia and Eurasia. Post-collisional volcanism started ca. 11Ma in Saray, east off the Urumieh Lake, which, along with later eruptions in Sahand (6.5–4.2Ma) and Sabalan (≤0.4Ma) volcanoes, forms a compositionally unique component of the vast volcanic field covering much of the Lesser Caucasus, NW Iran and eastern Anatolia regions. [Copyright &y& Elsevier]

Abstract: We present results of combined in situ U–Pb dating of detrital zircons and zircon Hf and whole-rock Nd isotopic compositions for high-grade clastic metasedimentary rocks of the Slyudyansky Complex in eastern Siberia. This complex is located southwest of Lake Baikal and is part of an early Paleozoic metamorphic terrane in the eastern part of the Central Asian Orogenic Belt (CAOB). Our new zircon ages and Hf isotopic data as well as whole-rock Nd isotopic compositions provide important constraints on the time of deposition and provenance of early Paleozoic high-grade metasedimentary rocks as well as models of crustal growth in Central Asia. Ages of 0.49–0.90Ga for detrital zircons from early Paleozoic high-grade clastic sediments indicate that deposition occurred in the late Neoproterozoic and early Paleozoic, between ca. 0.62–0.69 and 0.49–0.54Ga. Hf isotopic data of 0.82–0.69Ga zircons suggest Archean and Paleoproterozoic (ca. 2.7–2.8 and 2.2–2.3Ga; Hfc=2.5–3.9Ga) sources that were affected by juvenile 0.69–0.82Ga Neoproterozoic magmatism. An additional protolith was also identified. Its zircons yielded ages of 2.6–2.7Ga, and showed high positive ε Hf(t) values of +4.1 to +8.0, and Hf model ages t Hf(DM) = t Hfc =2.6–2.8Ga, which is nearly identical to the crystallization ages. These isotopic characteristics suggest that the protolith was quite juvenile. The whole-rock Nd isotopic data indicate that at least part of the Slyudyansky Complex metasediments was derived from “non-Siberian” provenances. The crustal development in the eastern CAOB was characterized by reworking of the early Precambrian continental crust in the early Neoproterozoic and the late Neoproterozoic–early Paleozoic juvenile crust formation. [Copyright &y& Elsevier]

Abstract: The West African Craton was the site of massive juvenile crustal addition in the early Proterozoic during the Eburnean orogeny (2.1Ga). In this study, we determined chemical and isotopic compositions as well as zircon U–Pb ages of granitoid samples from NE Burkina Faso. These data were then used to constrain the chemical characteristics, emplacement age and tectonic environment of these rocks in the context of the West African Craton evolution. Birimian (Paleoproterozoic) granitoids of NE Burkina Faso are associated with volcanic and volcano-sedimentary sequences of the greenstone belts. Analyses indicate that the Na-rich Birimian granitoids of tonalite–trondhjemite–granodiorite (TTG) composition were generated by partial melting of a garnet-bearing amphibolite crust. Granite intrusions derived from partial re-melting of the deep basement of felsic calc-alkaline nature with contribution of metasediments. Zircon U–Pb isotopic analyses yielded ages between 2122±15Ma and 2181±7Ma for the Birimian Na-rich granitoids and 2151±10Ma for a biotite granite (IJ10). Sr–Nd isotopic data show very low initial Sr composition (I Sr (T)≤0.7007), positive epsilon neodymium values (ɛNd (T)=+0.7 to +2.5) and Sm–Nd model ages (T DM) of 2363–2558Ma). These data are similar to those of mafic rocks of the Pissila greenstone belt: (I Sr (T)=0.7003–0.7015, ɛNd (T)=+3.2 to +4.1, T DM =2336–2552Ma), and further suggest that the Na-rich granitoids are of juvenile nature. The present study together with published data on the Birimian volcanics and meta-sedimentary rocks of the West African Craton preclude contamination of the juvenile Birimian rocks of NE Burkina Faso by reworked Archean materials. The Birimian granitoids of NE Burkina Faso were mostly emplaced during the early stage (2.19–2.15Ga) of a large scale crustal growth event (2.2–2.0Ga) where large amount of juvenile materials were added to the crust from the depleted mantle in a tectonic environment comparable to modern volcanic arcs. [Copyright &y& Elsevier]

Abstract: The Ailao Shan–Red River (ASRR) shear zone, one of the most prominent geologic strike-slip shear zones in Southeast Asia, consists of high-grade metamorphic complexes that provide a rare opportunity to sample the mid-crustal rocks along the western margin of the Yangtze Block of South China. Here we report combined, in-situ analyses of zircon U–Pb and Lu–Hf isotopes of eight gneisses from the Diancang Shan and Ailao Shan segments of the ASRR shear zone. Our zircon U–Pb data indicate that the rocks contain abundant magmatic zircons ranging in age from 1785 to 25Ma, with peak ages at ca. 770, 350 and 240Ma, suggesting three major periods of protolith formation. The 350-Ma zircons, observed only in an orthogneiss from the Diancang Shan, show uniform initial Hf isotopic ratios marked by high and positive εHf(T) values from +16 to +10. This is in contrast with the other two zircon populations that are more common, occurring in both the Diancang Shan and Ailao Shan, and overall delineate very heterogeneous Hf isotopic compositions, with εHf(T) values ranging from +15 to −16. Many zircons reveal distinctive core-rim age variations. Zircon rims, formed between ca. 34 and 26Ma, show significant variations in Th/U ratios (5–0.01) and εHf(T) values (+14 to −10) that suggest complicated magmatic and metamorphic zircon overgrowth during the Oligocene. The presence of both metamorphic and magmatic overgrowths on zircons suggests that the metamorphism reached upper amphibolite facies, corresponding to mid-crustal level P–T conditions, as also suggested by structural and petrologic data. Our data furthermore suggest that the ASRR gneisses were not produced solely by shear heating during the Tertiary strike-slip faulting, but are uplifted, mid-crustal basement rocks that formed essentially during two major stages of magmatism, represented by the Neoproterozoic Kangding Complex and Late Permian Emeishan large igneous province. As a result of the India–Asia collision, these basement rocks underwent regional magmatic and metamorphic overprinting in the Oligocene that, based on our relevant work (Searle et al., 2010, Geosphere, 6, 1–23), predated the initial left-lateral movement along the ASRR shear zone. The 350-Ma protolith, which requires a dominant depleted-mantle input in the petrogenesis, cannot be linked to any major magmatic events in South China but may be interpreted as part of the Paleotethys remnants that were later incorporated into the ASRR shear zone. [Copyright &y& Elsevier]

The Permian (~260 Ma) Emeishan large igneous province of SW China contains three nearly identical gabbro-granitoid complexes that host giant Fe-Ti oxide deposits. The Fe-Ti oxide deposits are within the lower portions of evolved layered gabbroic intrusions and are spatially and temporally associated with A-type granitic plutons. The 264 ± 3 Ma Taihe layered gabbroic intrusion hosts a large magmatic Fe-Ti oxide deposit and is coeval with die Taihe peralkaline, A-type granitic pluton, which is dated at 261 ± 2 Ma. Within the A-type granitic pluton are microgranular enclaves, which have compositions intermediate between the gabbro and host granite. Primitive mantle-normalized incompatible element plots show corresponding reciprocal patterns between the mafic and felsic rocks. The chondrite-normalized REE patterns show Eu-anomalies changing from positive (Eu/Eu* = 1.5 to 5.9) in the gabbroic intrusion to negative in the enclaves (Eu/Eu* = 0.4 to 0.6) and granites (Eu/Eu* = 0.2 to 0.5). Whole rock εNd(T) values of the gabbroic intrusion (εNd(T) = +2.5 to +3.3) are similar to those of the enclaves (εNd(T)) = +1.0 to 2.0) and granite (εNd(T)) = +1.5 to + 1.9) whereas the zircon εHf(T) values of the gabbro (εHf(T)) = +8.1 ± 0.8) are indistinguishable from those of the granites (εHf(T) = +9.2 ± 1.0), suggesting that the parent magmas for all rock types originated from the same mantle source. Geochemical modeling indicates that the gabbros and granites can be generated by fractional crystallization of a common parental magma similar to high-Ti Emeishan flood basalt. The compositional jump from the gabbro to the enclaves is attributed to the crystallization of Fe-Ti oxide minerals. The results of this study and other studies suggest that the magmatic conditions (for example, pressure, composition, fO2), which led to the formation of at least three Fe-Ti oxide bearing gabbro-granitoid complexes, were relatively common during the development of the Emeishan large igneous province. [ABSTRACT FROM AUTHOR]

Abstract: Before the Indian collision with Asia, northward subduction of the Neo-Tethyan oceanic lithosphere produced an Andean-type convergent margin in South Asia characterized by arc magmatism starting from the early Jurassic and lasting until the Eocene. The magmatic arc is now represented by widespread intrusive bodies or the so-called Transhimalayan batholiths in the Lhasa terrane of southern Tibet that have been divided into two main magmatic suites, i.e., the northern plutonic belt and the southern Gangdese Batholith. Their temporal distribution, concerning how exactly the magmatic suites correlate eastwards and then southeastwards around the eastern Himalayan syntaxis, however, remains poorly constrained. Here we report the first combined zircon U–Pb and Hf isotopic study of the Transhimalayan batholiths from the eastern part of the Lhasa terrane (∼95–97.5°E and ∼28.5–30°N), SE Tibet. Zircon U–Pb dating results of 24 granitoids indicate that the rocks were emplaced principally in the Early Cretaceous (∼133–110 Ma) and subordinately in the Paleocene (∼66–57 Ma), long after an older granite intrusion in the earliest Jurassic (∼198 Ma). The zircon ε Hf(T) values range from +5 to −20, yielding Hf crustal model ages (T DM C) between 0.8 and 2.4 Ga that peak at ∼1.7 Ga, suggesting a major episode of crustal growth in the Proterozoic and a predominantly, or even exclusively, crustal source for the granitoid petrogenesis. These zircon U–Pb and Hf isotopic constraints, together with whole-rock geochemical characteristics, allow us to correlate them to S-type granitoids in the northern plutonic belt, rather than to the I-type Gangdese Batholith from the central part of the southern Lhasa terrane. In contrast to the Gangdese magmatism that formed with a significant juvenile mantle input related to the Neo-Tethyan subduction, these S-type granitoids show geochemical similarities to the North American Cordilleran Interior batholiths that did not form directly from a subduction setting. Thus, we attribute the petrogenesis of the widespread Early Cretaceous granitoids in the northern belt and eastern Himalayan batholiths to a postcollisional regime due to the Late Jurassic–Early Cretaceous continental collision between the Lhasa and Qiangtang terranes. Under this framework, the S-type magmatism was generated in response to collision-induced crustal thickening, which may have capabilities of causing crustal anatexis by itself in the region. However, continued interplay with the Neo-Tethyan subduction zone processes such as back-arc extension could also have played a crucial, and long-lasting, role in the magma generation. [Copyright &y& Elsevier]

[Display omitted] • Malayan Southeast Coastal Zone recycled detrital zircon derived from Indochina. • Mid-Cenozoic Sundaland paleoriver carried detritus from Malaya to West Borneo. • West Borneo Cenozoic sediments' Indochina detrital zircon signature was from Malaya. Although Peninsular Malaysia abundant Permo-Triassic Malayan granitic plutons and volcanics (292–198 Ma) generate an enormous volume of detrital zircons that masks other detrital sources in fluvial sediments, there are suggestions that Peninsular Malaysia could recycle detrital zircons from Indochina (through Jurassic-Cretaceous strata) to other parts of Sundaland by paleoriver after the Indochina-Sundaland sediment link diminishes in the Cenozoic. As there is insufficient data to prove this, we compiled our new detrital zircon U-Pb isotopic data from modern river sands in Peninsular Malaysia with all available data to create a dataset that revealed five detrital zircon age pattern zones: (1) Northeast Coastal Zone (~73 Ma and ~223 Ma), (2) Mid-East Coastal Zone (~236 Ma and ~280 Ma), (3) Southeast Coastal Zone (~170 Ma, ~243 Ma, ~291 Ma, 400–416 Ma and 1545–1852 Ma), (4) Central Zone (~220 Ma) and (5) Mid-West Coastal Zone (~227 Ma and 1105–1173 Ma). All detrital age pattern zones show a clear detrital contribution from Malayan granitoids and volcanics. However, the Southeast Coastal Zone also shows significant contributions from Jurassic-Cretaceous strata in the northwest, e.g. Bertangga and Gerek sandstones, making them comparable with sources from Indochina and Lower Cretaceous strata in Singapore. We suggest a defunct drainage during Paleogene which transports the eroded sediments from the Jurassic-Cretaceous strata in the northwest to the sink in the southeast coast of Peninsular Malaysia recycled "Indochina signature" detrital zircons. If the sink connects with the Sundaland paleoriver system, it might contribute to the "Indochina signature" detrital provenance in West Borneo. [ABSTRACT FROM AUTHOR]

• The first U-Pb dates of diagenetic monazites were used to constrain depositional age of black shales containing the Lantian biota. • Sediment provenances of the eastern Nanhua basin during Ediacaran were identified. • Nature and timing of fluid flow events were discussed using late diagenetic xenotime and zircon. The Lantian formation, located in eastern South China block (SCB), forms the lower sequence of the Ediacaran period, at the transition from Proterozoic to Paleozoic. The fossils of Lantian formation have been proposed to predate the Avalon biota (about 579–565 Ma), the earliest known fossil assemblages with complex morphologies, based largely on stratigraphy. Mineral chemistry and in-situ U–Pb dating of monazites, xenotimes, and zircons from the black shale in fossil-rich zone are studied for the first time to provide critical age constraints for provenance, early diagenesis and fluid flow events. Detrital zircons and monazites give age populations similar to that of the Doushantuo formation, indicative of the same provenances for Ediacaran basins throughout the SCB. The low-Y monazites formed during early diagenesis yield a weighted mean age of 612 ± 29 Ma (n = 9, MSWD = 3.1). Age spectrum of analyzed monazites demonstrated that the sedimentation started from at least around 645 Ma. Subsequently, the overprinting events could be recorded by xenotimes and zircons precipitated from fluids during late diagenesis. Age results from xenotimes ranging from 441 Ma and 585 Ma were contemporaneous with the timing of collision of SCB with Gondwanaland, and a weighted mean age of 394.8 ± 3.7 Ma (n = 23, MSWD = 2.8) obtained from diagenetic zircons could be correlated to the post-tectonic granites widespread on the SCB. The pre-existing monazites generally remain pristine, and the multi-staged fluids were locally interacted with the samples to form Th-rich domains in monazites. [ABSTRACT FROM AUTHOR]