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The tectonic properties of the Nanping‐Ninghua tectonic belt (NNTB) play a crucial role in understanding the tectonic evolution of the Wuyi orogenic belt, which is related to the Neoproterozoic‐Paleozoic tectonic evolution of the Cathaysian Block. In this study, We present comprehensive petrological, geochronological, and geochemical data on the metavolcanic rocks from the Louqian Formation in Changting, Fujian Province. Our results show that volcanism in Changting occurred between 740.4 and 723.5 Ma, based on zircon U–Pb data for the metavolcanic rocks. The metavolcanic rocks have SiO2 contents ranging from 68.22 to 71.56 wt %, high Al2O3 and Na2O + K2O contents (13.30–15.19 wt % and 7.56–8.25 wt %, respectively), and low CaO, MgO, and FeOT contents (0.09–1.25 wt %, 0.72–0.96 wt %, and 1.57–3.16 wt %, respectively). These samples are enriched in large‐ion lithophile elements (LILEs) such as Ba and Rb, and depleted in high‐field‐strength elements (HFSEs) including Nb, Ta, and Ti, with significant negative Eu anomalies, indicating an affinity for arc igneous rocks. Based on previous geological studies, we suggest that the NNTB formed in an active continental margin environment during the Nanhua Period. The subduction of oceanic crust led to the formation of the volcanic belt along the Nanping‐Ninghua continental margin, which was active until 696 Ma. During the Neoproterozoic, the North and South Wuyi terranes did not merge to form a single Wuyi terrane, and the Cathaysia Block was composed of several terranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The protolith of Pb-Zn ore hosts is calcareous clastic rocks rather than regional metamorphic rocks. • We first reported the ages of Pb-Zn and Mo ores and their associated intrusion at Fengyan deposit. • Fengyan Pb-Zn and Mo mineralization are space-time and genetically related to granite porphyry. • The ore Mo was derived from a crust-mantle mixed Mo source dominated by crustal input. • A model is proposed to highlight the porphyry Mo and distal Pb-Zn ore system in Central Fujian. Central Fujian is an important Zn-Pb-Ag-Cu-Mo-Au mineral province in southeastern China, yet the polymetallic mineralization is still disputed between Proterozoic volcanogenic massive sulfide (VMS) or Mesozoic skarn type. The Fengyan is representative of the deposit type in central Fujian, characterized by shallow-level stratabound Zn-Pb mineralization and deep-level porphyry Mo mineralization. The ores are mainly hosted by Meso-Neoproterozoic marble and schists. Detailed field investigation, petrographic observation, and electron probe microanalysis indicate that the stratabound Zn-Pb ore host comprises a contact metamorphic/metasomatic suite. LA-ICP-MS zircon U-Pb dating of the granite porphyry yielded a weighted mean 206Pb/238U age of 145.0 ± 1.0 Ma (n = 17, MSWD = 0.97). Hydrothermal titanite grains in the stratabound Pb–Zn ores (intergrown with epidote and galena) yielded a weighted mean 207Pb-corrected 206Pb/238U age of 147.3 ± 4.4 Ma (n = 32, MSWD = 0.45), whilst molybdenite from the concealed Mo orebody has a Re–Os model age of ca. 145.3 to 145.5 Ma. Meanwhile, the molybdenite Re content and the published S-Pb isotope evidence indicate a crust source with minor mantle input. The largely similar age (within error) and ore-material source indicate that the Fengyan mineral system comprises an intrusion-proximal porphyry-type Mo mineralization and intrusion-distal Zn-Pb mineralization. This study proposes a genetic model for the mineral system, which would have important implications for exploring concealed porphyry Mo or Cu-Mo deposits, and/or their related magmatic-hydrothermal systems beneath/beyond these Zn-Pb(-Ag) deposits in central Fujian. [ABSTRACT FROM AUTHOR]

To investigate the tectonic framework of the basement of the Cathaysia Block, we selected the representative Cambrian strata in different parts of the South Wuyi area along the southern Nanping–Ninghua–Ganzhou Tectonic Belt (NNGTB). Integrated petrographic and geochronologic studies, as well as geochemical analysis, were carried out on the low‐grade metasedimentary rocks of the Niujiaohe Formation in south Jiangxi Province and the Lintian Formation in south‐west Fujian Province. The metasedimentary rocks of the Niujiaohe and Lintian formations are dominated by metasandstones and metasiltstones. They have low chemical index of alteration (52.6–77.4) and high index of compositional variability (0.84–1.42) values, suggesting weak chemical weathering and low clastic maturity. Their relatively low Th/U (4.12–6.81) and Rb/Sr (0.68–5.97) ratios reflect a simple recycling history. Detrital zircon geochronological studies indicate prominent source differences for the clastic rocks along the NNGTB. In the Ruijin area, the Niujiaohe Formation displays a Neoproterozoic peak at ca. 741 Ma, which is consistent with the widespread intermediate‐acid igneous rocks in the NNGTB. By contrast, the Lintian Formation from the Changting and Mingxi areas contains more pre‐Nanhuan detritus, which are predominantly in Grenvillian ages. Furthermore, the peak numbers of detrital zircon ages increase gradually from the Ruijin to Changting and Mingxi areas, indicating that their sources become more diverse. The geochemical features, in combination with detrital zircon age distributions, indicate that the Niujiaohe and Lintian formations are probably deposited in a back‐arc basin. These evidences suggest that the Cathaysia Block was assembled by multiple terranes during the Neoproterozoic to the Early Palaeozoic. [ABSTRACT FROM AUTHOR]

The nature of the Precambrian basement in the Cathaysia Block of South China is controversial, which inhibits our understanding of the pre‐Devonian tectonic evolution of the region. In this study, a suite of amphibolites and marbles in northern Fujian area located in the north of the Cathaysia Block were subjected to LA–ICP–MS U–Pb zircon geochronological and geochemical analyses. Results show that the protolith of the amphibolite formed after ca. 459 Ma, and its metamorphism happened at ca. 429 Ma. The protolith of the marble was deposited after ca. 518 Ma, and its metamorphic age is ca. 437 Ma. The amphibolites are divided into two groups based on geochemical data. Group 1 has an OIB‐like feature that might have formed in an environment characterized by oceanic islands and seamounts. Magmas associated with Group 1 were derived from an enriched mantle source with OIB characteristics. The protolith of Group 2 shows IAB feature that formed in an island arc environment. Marbles are interpreted to represent metamorphosed marine carbonate rocks. Integration of geochronological and geochemical study indicates that the marble and amphibolite should be an early Palaeozoic oceanic island–seamount association. It suggests the Cathaysia Block underwent oceanic subduction during collisional orogenesis in the early Palaeozoic. This subduction is thought to have initiated prior to ca. 437 Ma. The U–Pb zircon ages of younger intrusive granites indicate that final amalgamation occurred before ca. 392 Ma. During this process, east and west Wuyi were amalgamated to form the unified Cathaysia Block. Thus, it suggests that there was no unified pre‐Devonian basement in the Cathaysia Block. The pre‐Devonian tectonic setting of the Cathaysia Block was an accretionary orogeny. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal titanite yields a 207Pb-corrected weighted mean U–Pb age of 144 ± 2 Ma. • In situ sulfur isotope compositions of ore sulfides indicate a magmatic source. • The Dingjiashan deposit is a distal stratabound Pb-Zn-Ag skarn deposit. • Hydrothermal titanite is a reliable geochronometer for Pb-Zn-Ag skarn deposits. The Dingjiashan Pb-Zn-Ag deposit is predominantly hosted in the Proterozoic marble and partly in the Jurassic tuff and quartz sandstone in the central Fujian region of southeastern China. Four mineralization stages have been identified: (Ⅰ) prograde skarn (garnet + pyroxene + rhodonite), (Ⅱ) retrograde skarn (epidote + actinolite + tremolite + biotite + chlorite + ilvaite + magnetite + hematite), (III) sulfide assemblage (sphalerite + galena + pyrrhotite + pyrite + chalcopyrite), and (Ⅳ) quartz-calcite assemblage. In this contribution, LA-ICP-MS U-Pb analysis of hydrothermal titanite coexisting with quartz, epidote, biotite, magnetite, and sphalerite in the mineralized sample reveals 207Pb-corrected weighted mean 206Pb/238U age of 144 ± 2 Ma (n = 37, MSWD = 0.86, f 206 < 0.85). In situ sulfur isotope analysis of ore sulfides show a narrow variation of δ34S (-0.7 to + 5.5‰), which is consistent with a magmatic source. The geological, mineralogical, geochronological and in situ sulfur isotopic data collectively imply that the Dingjiashan is a distal stratabound Pb-Zn-Ag skarn deposit. This finding can aid understanding the genesis of other similar polymetallic deposits in the central Fujian region. Our data demonstrates that hydrothermal titanite is a reliable geochronometer for Pb-Zn-Ag skarn deposits and can aid in future prospecting and exploration for concealed porphyry Mo or Cu - Mo deposits that may be present below many of the Pb-Zn-(Ag) deposits in southeastern China. [ABSTRACT FROM AUTHOR]

Binary plots showed the distribution and variation of trace element concentrations in the four subtypes of sphalerite from the Dingjiashan Pb-Zn deposit compared to VMS and skarn Pb-Zn deposits. [Display omitted] • Four subtypes of sphalerite are identified in the Dingjiashan deposit. • Trace elements in sphalerite are used to discriminate VMS and skarn deposits. • LA-ICP-MS mapping method is used to investigate the occurrence state of elements. • Trace elements in sphalerite show a high-temperature hydrothermal system. • The Dingjiashan deposit is a Pb-Zn skarn deposit. The Dingjiashan Pb-Zn deposit (5.35 Mt Pb + Zn @ 1.14% Pb and 4.07% Zn) is hosted by pyroxene-dominated skarn occurring along the contact zones between Proterozoic quartz mica schist and marble in the central Fujian region of southeastern China. The ore genesis of Proterozoic volcanogenic massive sulfide (VMS) vs. Late Mesozoic skarn type has long been debated. In this study, two types of sphalerite (sphalerite I and sphalerite II) were identified based on the mineral assemblages in the sulfide stage of the Dingjiashan deposit. Sphalerite I (including sphalerite Ia and sphalerite Ib subtypes), with a dark gray-blue to black coloring, is predominantly associated with pyrrhotite, whereas sphalerite II (including sphalerite IIa and sphalerite IIb subtypes) shows a light to dark gray-blue coloring and is mainly associated with galena and chalcopyrite. Geological features indicate that sphalerite I predates sphalerite II. Representative time-resolved depth profiles and mapping images based on the LA-ICP-MS method, coupled with inter-element correlation analyses, collectively illustrated that: 1) Fe, Mn, Cd, Co, In, Ga and Ge are present in solid solution; 2) Cu may occur both as solid solution and as micro-inclusions; 3) Ag, Pb and Bi may be intimately associated with galena inclusions hosted by sphalerite. The characteristics of trace and minor elements (such as Fe, Mn, In, Co, Ga, Ge, etc.), along with the results of GGIMFis geothermometer studies, indicate that the main mineralization stage occurred at high-temperature conditions (>300 °C). Compared to Pb-Zn deposits (including 6 VMS deposits and 9 skarn deposits) worldwide, sphalerite from the Dingjiashan Pb-Zn deposit exhibits similar ore-forming temperatures and trace/minor element compositions to those from skarn deposits, but is different to those from VMS deposits. This finding is of great significance for further exploration in the Dingjiashan deposit and—more broadly—the entire central Fujian region. It also provides an important future guide for the differentiation of VMS and skarn deposits. [ABSTRACT FROM AUTHOR]

[Display omitted] • Basement controls Paleozoic Cu mineralization in southern and northern Wuyi. • Fe–Mn mineralization related to Late Paleozoic sedimentation in the Wuyi region. • Fe polymetallic deposits are strata-bound skarn-porphyry type composite deposits. • Cu deposits are polygenetic and superimposed and reformed hydrothermal deposits. The Wuyi metallogenic belt can be divided into the South and the North Wuyi metallogenic belt by the ENE-trending Nanping–Ninghua–Ganzhou Tectonic Belt. In the Wuyi metallogenic belt, Paleozoic mineralization, which has caused typical deposits such as the Yongping, Fenglin, and Yushui Cu deposits and the Makeng Fe deposit, exhibits notable variations. However, systematic research on the controlling factors of these mineralization episodes is lacking. In order to understand the Paleozoic minerlization in the Wuyi metallogenic belt, we study the genesis of typical deposits in Wuyi metallogenic belt. The phenomenon of "basal ore control" was observed as different basement units control different ore types in the Wuyi metallogenic belt. We believed that Paleozoic mineralization in the Wuyi metallogenic belt includes siliceous–carbonate Jingshe, Lindi, and Chuanshan Formations, which are related to the Fe–Mn deposits such as the Makeng Fe deposit, Dapai Fe–Pb–Zn deposit, and Luoyang Fe deposit in the Southwest Fujian Province, carbonate formations of the Hutian Group related to Cu deposits such as the Yushui Cu deposit in the North Guangdong Province of the southern Wuyi region, and the Carboniferous Outangdi Formation related to the Yongping and Fenglin Cu deposits in the Northeast Jiangxi Province of the northern Wuyi region. Based on a systematic analysis on typical metallogenic deposits and basement characteristics in the Wuyi metallogenic belt, we proposed that the Paleozoic mineralization is not only controlled by Paleozoic strata and Mesozoic magmatism, but also by the basement. The basement controls Paleozoic Cu mineralizations in the southern and northern Wuyi regions. However, Fe–Mn mineralization is mostly related to Late Paleozoic sedimentation. The superposition and transformation of Mesozoic magmatism to the basement and Paleozoic strata is an indispensable factor in the Cu and Fe–Mn mineralizations in the Wuyi metallogenic belt. [ABSTRACT FROM AUTHOR]