kalateh ahani is located 27 km southeast of gonabad within the khorasan razavi province. the area is part of lut block. sub-volcanic monzonitic rocks intruded regional metamorphosed shemshak formation (jurassic age). magnetic susceptibility of less altered monzonitic rocks is 0.6%., as, pb and zn > 1%, au up to 150 ppb and sn = 133 ppm. the sn content of vein in the northern part of kalateh aha...

Knowledge of the magnitude of differential stress and strain rate during the formation of mylonitic shear zones in metamorphic ore complexes provides constraints on the mechanical behavior of the middle continental crust during extension. We analyzed the differential flow stress during the mylonitization of quartzofeldspathic rocks in the Whipple Mountains, California, using grain-size piezomet...

U-Pb and Hf isotope analyses of zircons from felsic granulite xenoliths in Mesozoic volcanics reveal Early Archean ($3.6 Ga) lower crust beneath the younger (,2.85 Ga) southern margin of the North China craton, and suggest that the eastern part of the craton formed a coherent block by 3.6 Ga. Hf model ages indicate extraction of protoliths from the mantle ca. 4 Ga or earlier, followed by remelt...

the nayband strike-slip fault forms the western margin of the micro-continental lut block in eastern iran. neogene and quaternary mafic volcanic rocks collected near tabas, along the northern part of the fault (nnf; 15 ma), and further to the south, along the middle part of the fault (mnf; 2 ma), are within-plate sodic-series alkali olivine basalts with high tio2 and up to >16% normative nephel...

Whole-rock geochemical data on basaltic to rhyolitic samples from 12 volcanic centers are used to constrain the role of continental crust in the genesis of magmas formed beneath the anomalously wide subduction-related volcanic arc in Ecuador. Relatively homogeneous, mantle-like, isotopic compositions across the arc imply that the parental magmas in Ecuador were produced largely within the mantl...

Zircon age peaks at 2100–1650 and 1200–1000 Ma correlate with craton collisions in the growth of supercontinents Nuna and Rodinia, respectively, with a time interval between collisions mostly <50 Myr (range 0–250 Myr). Collisional orogens are two types: those with subduction durations <500 Myr and those ≥500 Myr. The latter group comprises orogens with long-lived accretionary stages between Nun...

The Nayband strike-slip fault forms the western margin of the micro-continental Lut block in Eastern Iran. Neogene and Quaternary mafic volcanic rocks collected near Tabas, along the northern part of the fault (NNF; 15 Ma), and further to the south, along the middle part of the fault (MNF; 2 Ma), are within-plate sodic-series alkali olivine basalts with high TiO2 and up to >16% normative nephel...

Assuming that the period 2.75–2.65 Ga corresponds to a single, but global, geodynamic event, we investigate—through numerical experiments—the mechanisms that could have led to the profound continental reworking that occurred at that time. Although the extent of the crisis at the Earth’s surface pledges in favour of the involvement of mantle plumes, our numerical experiments suggest that the the...