introduction the aqkand cu occurrence, 48 km north of zanjan, is located in the tarom subzone of the western alborz-azerbaijan structural zone. apart from small scale geological maps of the area, i.e., 1:250,000 geological maps of bandar-e-anzali (davies, 1977) and 1:100,000 geological maps of hashtjin (faridi and anvari, 2000) and a number of unpublished perlite exploration reports, prior to t...

The most frequent and voluminous eruptive Kurasawa, 1983], (4) partial melting of the lower crust products at Mount St. Helens are dacitic in composition, [e.g., Grant et al., 1984; Reid and Cole, 1983], and (5) although a wide variety of magma types (basalt to formation of compositional gradients in response to rhyodacite) is represented. To address the petrogenesis of convective and diffusive...

introduction the generation and evolution of granitic magmas has been a hot debated subject among petrologists. the diversity of their origin has led different authors to propose that these rocks are not simple in their origin and might be generated in more ways than one. in the past several decades, many petrologists used a variety characteristics to subdivide the granitoid rocks. such proposa...

introduction the ramand area, southwest of buin- zahra, about 60 kilometers from qazvin, lies in the igneous belt of the urmieh-dokhtar region, the main structural zone of north-central iran. rhyodacite and rhyolite lava flows are the principal host rocks of mineralization and alteration of the area, most of which occurs in faulted and brecciated zones alongmaj or northwest-trending fault syste...

introduction the kahang cu- mo deposit is situated approximately 73 km northeast of isfahan. asadi (2007) identified a geological reserve of 40 mt (proven reserve) grading at 0.53 cu, 0.02 mo and estimated reserve of 120 mt. all the rock types in the region have been subjected to hydrothermal solutions which gave rise to three different alteration facies. the dacite and rhyodacite volcanic rock...