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[Display omitted] • The Yare complex as well as granite units in the Mayum, Pujue, Nanmuqie, and Qiagong areas in the Gangdese magmatic arc were emplaced in Miocene. • The barren adakitic porphyries in Gangdese magmatic arc were derived from ancient crustal sources with little contributions from mantle-derived material. • The history of continuous and relatively complex magmatism prior to emplacement are important factors that discriminate between fertile and barren magmatism. Numerous Miocene porphyry deposits related to adakites have been identified in the eastern Gangdese magmatic arc (east of 87°E), but few of these type of deposits have been found in the western part (west of 87°E), even contemporaneous adakitic porphyries were exposed in the western part. A little research has been undertaken on barren adakitic porphyries in the Gangdese magmatic arc, and the key controls on the metallogenic differences remains unclear. This study presents new whole–rock geochemical, Sr–Nd isotopic, zircon U–Pb and Hf isotopic data for barren adakitic rocks of the Yare complex as well as barren porphyritic and adakitic units in the Mayum, Pujue, Nanmuqie, and Qiagong areas. These data are compared with data for fertile adakitic porphyries, providing insights into the origin and evolution of barren and fertile adakitic magmatism as well as the conditions associated with the porphyry mineralization. The barren adakitic porphyries were formed at 18.03–13.29 Ma. These intrusions have higher (87Sr/86Sr) i ratios (0.708752–0.709785) and lower Ɛ Nd (t) values (−8.4 to −6.5) and zircon Ɛ Hf (t) values (−13.81 to 3.23) than the fertile adakitic porphyries, suggesting the former were derived from ancient crustal sources with a little contributions from mantle-derived material. The fertile adakitic porphyries were formed as a result of partial melting of juvenile lower crust (such as Cu–Mo deposits) and with mixing of material from middle-upper crust (such as Mo–(Cu)–Pb–Zn deposits). The fertile adakitic porphyries also contain more water than the barren adakitic porphyries. Other important factors that discriminate between fertile and barren adakitic magmatism include the involvement of parental magma chambers as well as a history of continuous and relatively complex magmatism prior to emplacement. [ABSTRACT FROM AUTHOR]