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The early Jurassic black shales are the most important source rocks in the Qiangtang Basin, Tibet. These black shales may provide a useful example for understanding the sedimentary conditions during the early Jurassic in the eastern Tethys. Thirty-two black-shale samples were collected from the Qiangtang Basin to reconstruct the depositional environments during the early Jurassic in the eastern Tethys. The palaeoclimate index Σ(Fe + Mn + Cr + Ni + V + Co)/Σ(Ca + Mg + Sr + Ba + K + Na) varies between 0.58 and 1.14, together with low Sr/Ba (0.20-0.60) and Sr/Cu (1.68-7.88) ratios, indicating a warm humid to semi-humid climatic condition during black-shale deposition. The early Jurassic black shales exhibit slight Ce anomalies (0.89-0.94) and Mn enrichment (EF = 1.2), suggesting a slightly oxic depositional environment. The conditions of the sedimentary water system during black-shale deposition were apparently brackish as evidenced by middle B/Ga (3.96-5.73) and Th/U (3.96-6.51) ratios. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]