The Upper Cretaceous volcanic and subvolcanic rocks from the Nageleh Sar, south of Mahmood Abad town in north Iran are dolerite, olivine basalt, trachyandesite and alkali trachyte. These units in an ordered stratification are set in a way that creates a syncline with WNW-ESE axial trend. The chemical data and discrimination diagrams represent medium alkaline bimodal series for the studied sampl...

The Zaroo Cu-skarn is located NW of Yazd province, within the Cenozoic magmatic belt of Central Iran. The widespread rocks in the region are Eocene age volcanic with granitoids intrusives. The Cretaceous limestones in western parts of West Zaroo are hosted by skarn – marble mineralization. The skarns are distal type and are characterized by assemblage: Clinopyroxene, garnet, ilvaite, vezovianit...

Eocene volcanic rocks in NE of Ordib, have a very good exposures near and along the Turkmeni-Ordib fault. These rocks, that are situated in the inner part of the Central Iran and margin of the Yazd block, comprise trachyte, trachy-andesite and basaltic trachy-andesite. Trachy-andesite is the pervasive rock unit. Rock forming minerals of these rocks are chloritized olivine, plagioclase, pyroxene...

The clinopyroxene composition of two types of alkaline and calc-alkaline gabbros at Piranshahr pluton was investigated in this study. The major oxides variations are similar in all clinopyroxenes of two types of gabbros and are classified as diopside- augite; but trace element compositions are very different in these two groups. The clinopyroxenes of alkaline gabbros are rich in high field stre...

In Reza-Abad area (E- Shahrood city), diabasic dikes swarm (gabbro / diorite) with trends east-west intruded into Pre-Cambrian igneous - metamorphic complex of Central Iran Zone. These rocks display intergranular, ophitic and subophitic textures. Clinopyroxen (augite to diopside), plagioclase (oligoclase-andesine and labradorite- bitonite) and amphibole (magnesia hornblende) are the main minera...

Northeast  of Meshkinshahr, Eocene igneous rocks are exposed and are composed mainly of andesite, basalt, andesitic basalt, tephrite and is sometimes analcimite. The chemical composition of the rocks are in the range of alkaline rocks with high potassium and shoshsonitic affinity. Two main hypotheses are that they are either primary analcite or replacement pseudomorphous of leucite. Analcime cr...

The Plio- Quaternary volcanoes are located in the NE-Qorveh (Kurdistan) in the Qorveh-Takab volcanic belt, in the Hamedan-Tabriz Zone (HTZ). The volcanic rocks consist of basalt to olivine-basalt. The electron microprobe (EMP) analyses of pyroxenes show occurrence of one type of clinopyroxene, as diopside (Fs 2.65-6.42 En 40.44-50.47 Wo45.97-53.14) with Mg # = 84-98. The compositions of the pyr...

Pillow lavas are one of the important rock units of Nain ophiolite. Rock forming minerals of Nain ophiolite pillow lavas are chloritized olivine, plagioclase, clinopyroxene (augite), Cr-spinel, magnetite, amphibole, chlorite, pumpellyite, epidote, prehnite and calcite. Whole rock geochemical analyses and composition of clinopyroxenes and chromian spinels of these rocks indicate that they are si...