Accurately resolving the timing of formation of Au-Sb-W deposits hosted in metasedimentary rocks has been the aim of extensive research but has also led to controversy. In this study, we present high-precision laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb dating of hydrothermal apatite and wolframite from the Woxi Au-Sb-W deposit, South China. Veins are dominated by quartz, native gold, auriferous pyrite, arsenopyrite, stibnite, scheelite, wolframite, and apatite. Wolframite grains yield U-Pb ages of 144.8 ± 1.5 Ma (2s) and 140.3 ± 1.4 Ma, which overlap with apatite ages of 148.7 ± 2.4 to 144.1 ± 2.7 Ma. Collectively, the new data confirm the Woxi deposit is solely Late Jurassic-Early Cretaceous in age, despite previous dates using other isotopic systems that were as old as Silurian. Our compilation of geologic characteristics, tectonic setting, and geochronology of Au-Sb-W deposits from the western part of the Jiangnan belt shows there were two episodes of Au-Sb-W metallogenesis. These events in the Late Triassic and Late Jurassic-Early Cretaceous related to an extensional setting following Triassic intracontinental orogeny and to Late Jurassic-Early Cretaceous extension associated with Izanagi plate rollback, respectively.

Garnet is a key and defining mineral of skarns and associated metalliferous deposits. Variation in garnet composition, commonly expressed by the proportions of different end‐members, is widely used to determine the physical–chemical features of hydrothermal fluids. Skarn garnets from the Fujiashan W‐Cu‐Mo deposit, eastern China, were investigated by Raman spectroscopy and electron probe microanalysis to assess the quantitative correlation between Raman band positions and proportions of garnet end‐members. Compositions and Raman band positions of so‐called “grandite” garnet (Adr18–98Grs0–79), where Adr and Gr are the end‐members andradite and grossular, respectively, display a spatial zonation at Fujiashan that correlates with the distance from the contact between skarn and causative intrusion. Raman band positions determined in the ranges 234–246, 351–368, 369–375, 515–544, 814–826, and 873–882 cm−1 demonstrate moderate to very strong (R2 up to 0.99) linear correlations with mol% andradite and grossular components. This is attributed to homovalent substitution between Fe3+ and Al3+ in the octahedral site, which has an indirect effect on bond lengths and angles of Si‐O vibration, resulting in linear variation of Raman band positions. The band between 515 and 544 cm−1 is the most sensitive to compositional variation, and its position enables robust estimation of end‐member proportions within 10% of results calculated from electron probe microanalysis. This research highlights the potential of Raman spectroscopy as a rapid, powerful method to assess the composition of skarn garnet, enabling accelerated construction of spatial zonation models for skarns during skarn deposit exploration.

When the desired signal and multiple mainlobe interferences coexist in the received data, the performance of the current mainlobe interference suppression algorithms is severely challenged. This paper proposes a multiple mainlobe interference suppression method based on eigen-subspace and eigen-oblique projection to solve this problem. First, use the spatial spectrum algorithm to calculate interference power and direction. Next, reconstruct the eigen-subspace to accurately calculate the interference eigenvector, then generate the eigen-oblique projection matrix to suppress mainlobe interference and output the desired signal without distortion. Finally, the adaptive weight vector is calculated to suppress sidelobe interference. Through the above steps, the proposed method solves the problem that the mainlobe interference eigenvector is difficult to select, caused by the desired signal and the mismatch of the mainlobe interference steering vector and its eigenvector. The simulation result proves that our method could suppress interference more successfully than the former methods.