Effects of hydrothermal fluids on carbonate reservoirs: Case from the lower Permian Sichuan Basin (Qixia Formation), China, by Di Xiao, Jian Cao, Xiucheng Tan, Long Wen, Ran Liu, Feifan Lu, Minglong Li, Feng Liang, and Jianfeng Zheng. The effects of hydrothermal ?uids on carbonate reservoirs are a critical issue in petroleum geology. The authors present a comprehensive study of the lower Permian Qixia Formation in the Sichuan Basin, China, based on petrology, geochemistry, and geochronology. Their research highlights that hydrothermal effects on reservoirs cannot be generalized and that the origin and properties of hydrothermal fluids and modified lithologic associations should be comprehensively considered, as they produce diverse hydrothermal effects.