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In the northeast of Iran, there are some outcrops of high-Mg ultramafic volcanic rocks. These rocks have been interpreted as an ideal ophiolite sequence related to the closure of Paleo-Tethys. According to detailed field observations, the komatiitic lava flows in Shandiz- Virani- Mashhad Complex (SVMC) and Fariman Complex (FC), are interlayered with the Upper Paleozoic submarine turbiditic sediments (Carboniferous-Permian). These rocks have a wide range of volcanic facies and according to the lithofacies characteristics, are divided into three groups of differentiated, undifferentiated lava flows and pillow lavas with a variety of volcanic textures and glass groundmass and with the main minerals of olivine, chromian spinel, clinopyroxene and amphibole. In this paper, the komatiitic nature of these rocks has been proven by explicit evidence from the field characteristics, petrography, internal stratigraphy and mineral chemistry. Also, the interaction of a mantle plume with the late Paleozoic (Permian) northeast subduction zone of Paleo-Tethys in NE Iran is considered as the suitable petrogenetic model involved in the genesis of the Komatiitic magma. This model can well justify and interpret the various geochemical characteristics of the studied rocks.

In the northeast of Iran, there are some outcrops of high-Mg ultramafic volcanic rocks. These rocks have been interpreted as an ideal ophiolite sequence related to the closure of Paleo-Tethys. According to detailed field observations, the komatiitic lava flows in Shandiz- Virani- Mashhad Complex (SVMC) and Fariman Complex (FC) are interlayered with the Upper Paleozoic submarine turbiditic sediments (Carboniferous- Permian). These rocks have a wide range of volcanic facies and according to the lithofacies characteristics, are divided into three groups of differentiated, undifferentiated lava flows and pillow lavas with a variety of volcanic textures and glass groundmass and with the main minerals of olivine, chromian spinel, clinopyroxene and amphibole. In this paper, the komatiitic nature of these rocks has been proven by explicit evidence from the field features petrography, internal stratigraphy and mineral chemistry. Also, the interaction of a mantle plume with the late Paleozoic (Permian) northeast subduction zone of Paleo-Tethys in NE Iran is considered as the suitable petrogenetic model involved in the genesis of the Komatiitic magma. This model can well justify and interpret the various geochemical characteristics of the studied rocks. [ABSTRACT FROM AUTHOR]

Introduction Mineral composition is sensitive to variations in the composition of the magma and can be used to characterize the physical conditions of crystallization such as temperature, pressure, oxygen fugacity and water content. The studies have demonstrated that geobarometery by amphibole provides a tool for determining the depth of crystallization and knowledge of the depth of crystallization of hornblende through to solidification of calc-alkaline plutons (Anderson and Smith, 1995). The composition of pyroxene can be used as crystallization pressure and temperature indicators of pyroxene too. Anlytical methods The mineral compositions of the Nasrand intrusion were determined by electron microprobe, with special emphasis on the amphibole, feldspar, and pyroxene at the Naruto University, Japan, the EPMA (Jeol- JXA-8800R) was used at operating conditions of 15 kV, 20 nA acceleration voltage and 20s counting time. Results The Nasrand intrusion (33°13'–33°15' N, 52°33'–52°34'E) with an outcrop area of about 40 km2 is situated in the Urumieh–Dokhtar magmatic belt, SE of Ardestan. It is composed of granite and granodiorite and various dikes of diorite and gabbro which are intruded in it. It is intruded into Eocene volcanic rocks, including andesite, rhyolite, and dacite. The petrographical studies indicate that the granitic and granodioritic rocks contain major minerals such as quartz, K-feldspar, plagioclase, and amphibole, which are in an approximate equilibrium state. The gabbroic-dioritic dikes usually show microgranular porphyric texture. They mainly consist of plagioclase, amphibole, and pyroxene. The plagioclase shows variable composition from albite to oligoclase in the granitoid rocks and from oligoclase to bytownite in dioritic and gabbroic dikes (Deer et al., 1991). The amphiboles are calcic and their composition varies from hornblende to actinolite, whereas the composition of the basic dikes is inclined to hastingsite (Leake et al., 1997). Actinolitic probably crystallized as a subsolidus phase. Pyroxene in the dikes is clinopyroxene with augite- diopside composition (Morimoto, 1988). Discussion The total Al content of hornblende is a sensitive linear function of crystallization pressure and temperature (Schmidt 1992; Holland and Blundy, 1994). However, the computed pressure may reflect the level at which the hornblende crystallizes rather than the pressure at which the granite consolidates. Therefore, Al content in hornblende geobarometer is only applicable in the presence of quartz and plagioclase; alkali feldspars, biotite, hornblende, clearly limit compositional influences (Ague, 1997). Oxygen fugacity has a marked effect on the mineral system, so only hornblendes with Fe/(Fe+Mg) < 0.65, Si ≤7.5 and Ca ≥1.6 were used for geobarometry and are not applicable to subsolidus actinolite (Stein and Dietl, 2001). The average formation pressure in the intrusive rocks is evaluated to be 1.54 kbar by Schmidt (Schmidt, 1992) and Anderson and Smith (Anderson and Smith, 1995) equations, which is consistent with a depth of 5.9 Km, whereas the average pressure of amphibole crystallization in the dioritic dikes is calculated to be about 2.96 Kbar by the Ridolfi equation (Ridolfi et al., 2010), indicating 11.4 Km depth. The estimated pressure for clinopyroxene crystallization in the dikes is calculated to be about 4–8 kbar by the Soesoo (Soesoo, 1997) and Putirka (Putirka, 2008) equations which is reflecting the initial crystallization pressure of pyroxene from magma which corresponds to depths of about 15-30 km. The average formation temperature of the intrusive rocks and amphiboles in dioritic dikes is estimated to be 700 and 940 °C respectively, by the Holland and Blundy (Holland and Blundy, 1994), Vyhnal et al. (Vyhnal et al., 1991), and Ridolfi et al. (Ridolfi et al., 2010) equations. The highest temperatures from pyroxene thermometry in the dikes is about 1150 – 1250 °C by Soesoo (Soesoo, 1997) and Putirka (Putirka, 2008) equations which are assumed to reflect the actual temperature of initial pyroxene crystallization and are usually higher than temperatures obtained by hornblende-plagioclase thermometry. Oxygen fugacity in the granitoid rocks and dioritic dikes is above the Ni-NiO buffer and it is indicated to be -12.9 and 10.5 bars, respectively, by the Ridolfi et al. (Ridolfi et al., 2010) equation. Water contents in the granitoid rocks and dikes are calculated to be about 3.6 and 4.6 wt. % respectively, by the Ridolfi et al. (Ridolfi et al., 2010) equation, i.e. for typically subduction - related environments. References Ague, J.J., 1997. Thermodynamic calculation of emplacement pressures for batholithic rocks, California: Implications for the aluminum-in-hornblende barometer. Geology, 25(6): 563-566. Anderson, J.L. and Smith, D.R., 1995. The effects of temperature and ƒO2 on the Al-in-hornblende barometer. American Mineralogist, 80(5-6): 549-559. Deer, W.A., Howie, R.A. and Zussman, J., 1991. An introduction to the Rock forming minerals. Longman, London, 969 pp. Holland, T. and Blundy, J., 1994. Non-ideal interactions in calcic-amphiboles and their bearing on amphibole-plagioclase thermometry. Contribution to Mineralogy and Petrology, 116(4): 433-447. Leake, B.E., Woolly, A.R., Arps, C.E.S., Birch, W.D., Gilbert, M.C., Grice, J.D., Hawthorne, F.C., Kato, A., Kisch, H.J., Krivovichev, V.G., Linthout, K., Laird, J., Mandarino, J., Maresch, W.V., Nickel, E.h., Rock, N.M.S., Schmucher, J.C., Smith, D.C., Stephenson, N.C.N, Unungaretti, L., Whittaker, E.J.W. and Youzhi G., 1997. Nomenclature of Amphiboles, Report of the Subcommittee on Amphiboles of the International Mineralogical Association Commission on New Minerals Names. Europian Journal of Mineralogy, 9(3): 623-651. Morimoto, N., 1988. Nomenclature of pyroxenes. Fortschr mineral, 66(2): 237–252. Putirka, K.D., 2008. Thermometers and Barometers for Volcanic Systems. Reviews in Mineralogy and Geochemistry, 69(1): 61-120. Ridolfi, F., Renzulli, A. and Puerini, M., 2010. Stability and chemical equilibrium of amphibole in calc-alkaline magmas: an overview, new thermobarometric formulations and application to subduction-related volcanoes. Contributions to Mineralogy and Petrology, 160(1): 45–66. Schmidt, M.W., 1992. Amphibole composition in tonalite as a function of pressure an experimental calibration of the Al-hornblende barometer. Contributions to Mineralogy and Petrology, 110(2-3): 304-310. Soesoo, A., 1997. A multivariate statistical analysis of clinopyroxene composition: empirical coordinates for the crystallisation PT-estimations. Geological Society of Sweden, 119(1): 55-60. Stein, E. and Dietl, E., 2001. Hornblende thermo barometry of granitoids from the central Odenwald (Germany) and their implication for the geotectonic development of the Odenwald. Mineralogy and Petrology, 72(1-3): 185-207. Vyhnal, C.R., Mcsween, H.Y. and Speer, J.A., 1991. Hornblende Chemistry in Southern Appalachian Granitoids: implications for aluminum hornblende thermo barometry and magmatic epidote stability. American Mineralogist, 76(1-2): 176-188.

Introduction: cardiac surgery by cardiopulmonary bypass (CPB) is performed accompanying with hypothermia. Measuring the body temperature during hypothermia is very important. The aim of this study was to compare esophageal, tympanic and rectal temperatures in pediatric patients below 12 years old undergoing open heart surgery. Methods: This study was a cross-sectional descriptive and analytic study. The sample consisted of 70 patients below 12 years old undergoing open heart surgery in Rajaee Heart Centre in Tehran. Esophageal, rectal and tympanic temperatures were measured by thermometer in three phases: before CPB, during CPB and after weaning of CPB. The collected data were analyzed by SPSS 16 software using paired T-test and ANOVA (Analysis of Variance). Results: The mean of body temperature was different in the three sites. The difference between right and left ear was not significant, but the difference between esophagus –rectum, esophagus-tympanum and rectum-tympanum was significant (P

The zircon crystallization is a function of temperature, composition and water content of magma, also its crystal shape and size depends on velocity of crystallization and Zr saturation, then we have focused on the study of zircon crystals in Hormuz rhyolites from four salt domes in different localities (Gachin, Bandare Moallem, Hormuz and Larak Islands) based on the morphology study. The most of studied zircons are plotted in the P3 and P4 areas and the less lie in the P5, P2 and S15 domains. Crystals morphology, lack of hydrozircon overgrowth and apatite or monazite inclusions in zircons indicating that they have crystallized from an I-type rhyolitic magma. Zircon morphology pointing on moderately alkaline and dry nature of parental magma. Based on morphology, zircon saturation temperature and whole-rock geochemistry calculation, the minimum temperature of zircon crystallization is ranging from 750 to 840˚C. Coexistance of euhedral elongated zircons with wide and short zircon crystals indicate the super-saturation of Zr in the responsible magma from early stage, which is also confirmed by thin zonation features. [ABSTRACT FROM AUTHOR]

The Tutak metamorphic complex located in the southern part of the Sanandaj-Sirjan zone, is among the areas where the Paleozoic rocks are well exposed. This metamorphic complex mainly comprise of the Cambrian to the early Carboniferous marble, schist, amphibolite and genesis units. Garnet-biotite thermometric method and Garnet-biotite-muscovite barometric method carried out on dark schist from the Tutak metamorphic complex repersent 423 °C and 1.6 kb in the early stage of metamorphism to 708 °C and 5.9 kb during peak of metamorphism. These temperatures and pressures point to amphibolite facies conditions. The thermal cessation and also the marked difference in the degree of metamorphism between the Tutak complex and the late Carboniferous- early Permian succession in Surian, indicate that this phase of metamorphism probably occurred prior to the Late Carboniferous period. [ABSTRACT FROM AUTHOR]

There are various contact and regional metamorphic rocks, from low to high grade in contact of the Alvand plutonic body. These rocks have undergone regional dynamothermal metamorphism and in the later stage due to heat and fluids derived from the body have been subjected to contact metamorphism. Hornfelses from the east and the north-eastern part of the Alvand aureole have sedimentary protolith of shale type. In the studied hornfelses, garnets are almandine-rich; composition of biotite is sidrophyllite and of the plagioclase varies from albite to andesine. Based on thermometric cation-exchange method of garnetbiotite pair, using different calibrations, the obtained temperature for cordierite-free hornfels, is about 580 °C and for the cordierite-bearing hornfels 566 °C. In barometry with GPBQ system, calculated pressure for hornfelses is strongly consistent with pressure obtained from multiple equilibrium curves for these rocks and was estimated to be about 2.9 to 3.6 Kbar. The obtained temperature and pressure using composition from rim of minerals in cordierite- and aluminosilicate-bearing rocks, with multiple equilibrium curves and THERMOCALC software represent temperature of about 650 °C and pressure of 3 Kbar. [ABSTRACT FROM AUTHOR]