نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشگاه شهید چمران اهواز
2 گروه زمین شناسی، دانشکده علوم زمین، دانشگاه شهید چمران اهواز، اهواز، ایران
3 دانشکده علوم زمین، دانشگاه دامغان، دامغان، ایران
4 گروه زمین شناسی، دانشکده علوم زمین، دانشگاه شهید چمران اهواز ، اهواز، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The Kuh Kaput porphyry copper deposit, located north of Bam in the southern Kerman Magmatic Copper Belt, is associated with microquartz diorite intrusions emplaced within Eocene volcanic rocks. To investigate magmatic evolution and its relation to mineralization, trace and rare earth element compositions of zircon from two microquartz diorite bodies (HBQD and DPQD) and one microgranodiorite body (GD03) were analyzed using LA ICP MS. Zircon geochemical patterns, including HREE enrichment relative to LREE, positive Ce anomalies, and negative Eu anomalies, confirm their magmatic origin. Estimated zircon crystallization temperatures range from 659 to 780 °C, while ΔFMQ values indicate oxidizing magma conditions. Zircons from the microquartz diorite bodies exhibit relatively high Eu/Eu* values (>0.4), suggesting oxidized and water rich magmas and indicating fertile intrusions. Trends of constant Eu/Eu* versus Hf and increasing (Yb/Gd)ₙ versus Hf imply magma evolution dominated by amphibole and apatite fractionation. In contrast, the microgranodiorite intrusion shows lower Eu/Eu* values (<0.4), indicating a less hydrous and infertile magma, with evolution largely controlled by plagioclase fractionation. Drill core observations and lithological logging indicate that the microgranodiorite represents an earlier magmatic phase, whereas the microquartz diorite intrusions correspond to later magmatic stages. The progressive increase in zircon Eu/Eu* ratios from older to younger intrusions suggests magmatic evolution toward more hydrous conditions, which significantly enhanced the mineralization potential in northern Bam. Evidence of hydrothermal fluid exsolution from the oxidized and water rich HBQD magma indicates that this intrusion represents the principal mineralization related phase.
کلیدواژهها [English]
)