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The Yinggehai-Song Hong (Y-SH) Basin, located on the northwestern shelf of the South China Sea, is one of the world's largest pull-apart basins. In order to identify the provenance of the Upper Miocene to Quaternary sediments of the basin, ten sediment samples were collected from drill cores in the Dongfang gas field. U--Pb dating of detrital zircon grains extracted from the ten samples using a laser ablation inductively coupled mass spectrometer (LA-ICP-MS) yields ages ranging from the Archean to Cenozoic (2898 ± 46 Ma to 26 ± 1 Ma). The zircon U--Pb age spectra of the Upper Miocene to Quaternary show a similar pattern with major peaks clustered at ca. 32 Ma, ca. 99 Ma, ca. 160 Ma, ca. 247 Ma, ca. 422 Ma and three "broad" age groups, 600-1000 Ma, 1700-2100 Ma and 2200-2800 Ma, suggestive of a wide range of igneous rock ages in the source areas. The detrital zircon ages provide diagnostic criteria for identification of the various source areas and reveal that the detritus was derived from multiple sources. Comparison of the results with the rock types and their ages surrounding the potential source areas indicates that the clastic material was derived from three dominant age sources: (1) Yangtze Craton, (2) Hainan Island and (3) Indochina Block. The Yangtze Craton was a major and continuous source area contribution to the basin. Comparing the age characteristics and its source areas since 10 Ma, the largely stable provenance also suggests that if the Red River capture ever existed it should have happened before the Late Miocene. [ABSTRACT FROM AUTHOR]

The article reports on uranium-lead (U-Pb) geochronology of detrital zircon and the provenance of Sanya formation at the Yinggehai Basin in South China Sea. It highlights the acquisition of zircons from heavy liquids through a Frantz magnetic separator as well as fastened in epoxy. An overview of its morphology is also presented.