جستجوی مقالات مرتبط با کلیدواژه "نوار دهج- ساردوئیه" در نشریات گروه "زمین شناسی"

In the Pariz area, (Kerman province), there are deposits that have been identified in the geological maps as detrital unconsolidated Neogene Conglomerates (Ng) units. Studies on these deposits reveal that they are pyroclastic deposits from Neogene explosive eruptions. The units overlie the Eocene igneous rocks and their fragments are dacite and rhyolite .These deposits are pyroclastic surges and flow deposits in association with the laharic units. The types of pyroclastics, absence of dacitic or rhyolitic lava flows and large dispersal of these deposits, show that their eruptions were explosive and that water was involved in the eruptions. Slight variations in the amounts of major oxides such as SiO2 and MgO (64.5-68.2 and 0.43-1.1 wt%, respectively) in these rocks indicate a little crystal differentiation and the lack of compositional variations of their parent magmas. Negative Nb, Ti, and P, along with the positive Sr and Cs anomalies in the spider diagrams can indicate that these rocks are belong to calc-alkaline magmatic series. Enrichment of LREE to HREE (average LaN/LuN = 20) is characteristic of these rocks. The studied rocks belong to the post-collision environment and reflect the nature of continental magmatic arc associations.

In the southeast of Uromieh-Dokhtar volcanic belt، southeast of Bardsir (Kerman province)، there are numerous gabbroic، dioritic and tonalitic intrusive bodies crosscutting the basaltic، andesitic lava flows and the pyroclastics of the Eocene age. The widespread distribution of intrusive rocks in the studied area، mineralogical similarity between these plutons and the volcanics as well as very similar chemical compositions of these two groups of rocks in different geochemical and tectonomagmatic discrimination diagrams suggest that the plutonic and the volcanic rocks may have been originated from the same origin. Geochemical characteristics indicate that the ntrusives are calcalkaline and LREE-enrichment as compared with HREE، high contents of LILE relative to HFSE and the significant anomalies of Nb، Ti and P reveal that they belong to a subduction-related magmatism. All these evidences show that in the studied area parental agmas of both plutonic and volcanic rocks، have been originated from partial melting of a metasomatized mantle wedge. The mantle probably enriched in incompatible elements by the slab derived fluids.