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Stratiform barite deposits(SB) and vein Pb-Zn barite deposits(VB) are known in a rift basin in centralGuangxi. The former is hostrd in the Upper Devonian cherl beds and the lalter occurs in the Middle and LowerDevoman nerihe sediments. The two types of mineralization are believed to have a common origin asevidenced by the following observahons: (1)Spahally, they are closely associated with each other.(2) Theypossess. a basie similarily. but also show systematic variations from VB to SB in terms of ore composition,structural and textural features, temperalure of mineralizing solutions, country rocks and alteration. (3) Theirδ~(34)S values are more similar to the average value of marine sulfate in Late Devonian than to that in EarlyDevonian. A model for thermal water deposition has been proposed to illustrate the genesis of these deposits.
The former is hostrd in the Upper Devonian cherl beds and the lalter occurs in the Middle and LowerDevoman nerihe sediments. The two types of mineralizations are believed to have a common origin a virgind by the following observahons: (1) Spahally, they are closely associated with each other. (2) Theypossess. a basie similarily. but also show systematic variations from VB to SB in terms of ore composition, structural and textural features, temperalure of mineralizing solutions, country rocks and alteration. (3) Their δ ~ (34) S values are more similar to the average value of marine sulfate in Late Devonian than to that in Early Devonian. A model for thermal water deposition has been proposed to illustrate the genesis of these deposits.