关键词: 南海, 火山玻璃, 沉积作用, 物源, 火山-地震带, 14C测年, 氧碳稳定同位素

Abstract: The Luzon Arc in the eastern margin and Sunda-Java Arc in the southern margin of the South China Sea (SCS) are important volcano-seismic belts, with their volcanic glass serving as the main sediment source in SCS. Volcanic glass was identified in a large number of columnar cores to analyze its distribution characteristics, supplemented by ¹⁴C dating and oxygen-carbon stable isotope determination. The results show that the distribution characteristics of columnar volcanic glass are similar to those of surface sediment samples, peaking in the eastern SCS and spreading outward, indicating the primary source is still the Philippine Islands. However, the volcanic provenances from the Sumatra-Java Arc volcano-seismic belt since  Late Pleistocene exceed those from surface sediments. The volcanic glass content of MIS1 in the northeastern SCS is greater than in MIS2, suggesting enhanced volcanic activity of MIS1 in the northern Luzon Arc. The absence of volcanic glass in the northern shelf and slope area of the SCS indicates a lack of recent volcanic activity from the northern South China continent, exerting minimal influence on the near-surface sediments of SCS.

Key words: South China Sea, volcanic glass, sedimentation, provenance, volcano-seismic belts；14C dating；oxygen-carbon stable isotope