Hasil untuk "Mineralogy"

Marenco F., Kezoudi M., Papetta A. et al.

The Cyprus Institute has acquired expertise during the ASKOS campaign, for the Cal/Val of Aeolus, through the deployment of our UAVs in Cabo Verde, equipped with aerosol and cloud instruments (optical particle counters, backscatter sonde, and impactors for dust sample collection). The UAVs reached altitudes up to ~5,000 m above sea level, and measured the height-resolved particle size-distribution and the mineralogy of airborne dust, and were co-located with ground-based remote sensing activities. These observational platforms will also be deployed for the Cal/Val of EarthCARE, expected to be launched this year, together with our ground-based lidar, sunphotometers and ceilometers. In this presentation, I will present these efforts, discuss the strategic location of Cyprus for aerosol studies, and highlight the great potential coming from the collaboration with the nearby remote sensing facilities of the ERATOSTHENES centre of excellence.

Christian Leipe, David Handfried, Tengwen Long et al.

Here, we present the first fully varve-based chronology for the deposits of the deep-water Lake Shira (Chulym-Yenisei Basin, South Siberia), derived from a new sediment core. The very well-preserved varves show typical properties of the clastic-biogenic and endogenic types that can be subdivided into four sublayers representing winter–early spring, late spring, early summer and late summer–autumn. The analysed sediment section of 147 cm length comprises 2491 varve years with a total counting error of 1.6 % (i.e. ±40 years), making the new sediment core from Lake Shira a unique high-resolution archive for multi-proxy studies of past climate/environmental change and human-environment interactions. Direct comparison of nine AMS radiocarbon (14C) dates based on sediment bulk organic fractions with an age-depth model based on varve counting made it possible to examine the 14C reservoir effect in the lake. The reservoir effect is a common issue when estimating the age of environmental proxies from lacustrine sedimentary archives in Inner Asia. Although a constant reservoir effect is commonly used to correct the 14C dates from a single core or lake basin, our results from Lake Shira demonstrate that it varies significantly over the last 2500 years, ranging from 240 ± 30 to 1045 ± 30 years. The spatiotemporal variability of the reservoir effect can considerably reduce the accuracy of age-depth models based solely on the bulk organic sediment fraction. Where varved sediment is unavailable, as is usually the case, lignin phenols, terrestrial plant remains and purified pollen concentrates should be considered as alternative dating materials.

Assaf Miron, Rafael Tadmor, Victor Multanen et al.

Abstract This study investigates the fundamental frictional behavior of granules through experimental analysis under two direct-shear testing scenarios: grains-assembly shearing and grains-to-surface shearing (when the shear plane is between the grains and a flat solid surface), incorporating new experimental data with comparison to previous findings. By varying grain mineralogy, morphology, and pore liquids, we identify key differences between the two systems. The results show that grain-assembly friction is influenced by grain morphology but not by mineralogy, whereas grains-to-surface friction exhibits the opposite trend. The presence of pore liquid also has contrasting effects: it reduces friction in grain-assemblies due to lubrication but increases friction of grains-surface systems due to solid-liquid adhesion. This paper explains these trends by hypothesizing a link between each shearing scenario to distinct grain displacement mechanisms—particle sliding or rolling (rearrangement). It also shows that the friction of an ‘ideal’ granular system, made of uniform, rigid, and smooth spheres, sets a threshold for the effects of lubrication and adhesion.

V. V. Marusin, B. B. Kochnev, G. A. Karlova et al.

The Precambrian to Cambrian strata at the southwestern margin of the Siberian Platform are ubiquitously characterized by a gradual transition from red-colored alluvial and deltaic deposits to shallow-marine carbonates, reflecting a transgressive infill of the accommodation space of the foreland basin. However, a supposed synchronicity of the Early Precambrian marine transgressive events calls for verification by geochronological and bio- and chemostratigraphic dating. The herein-presented data on small skeletal fossils, trace fossils and variations in the carbon isotope composition of carbonates from the mixed carbonate-terrigenous succession (Redkolesnaya and Ostrovnoy formations) in the southern Yenisei ridge show that the base of the Cambrian Fortunian stage is placed within the Redkolesnaya formation. Age distribution of detrital zircons in the studied succession suggests the Siberian craton to be a major source of the clastic material in the foreland basin during the development of the Redkolesnaya formation. An increase in the amount of zircons derived from "non-Siberian" sources, located at the southwestern periphery of the paleocontinent at that time, in the coeval strata of the northern part of the southern Yenisei ridge, indicates a complex morphology of the paleobasin and considerable differentiation among the sources of clastic material therein.

Sin Yi Ling, Junaidi Asis, Baba Musta

The type of minerals in sediments control the geochemical distribution of metals which serve as an indicator of the pollution status to the marine environment. The type of minerals was determined from X-ray diffraction (XRD) and scanning electron microscope (SEM) which shows the dominance of carbonate (calcite, aragonite, dolomite), silicate (quartz) and minor clay (illite, kaolinite) minerals. The elemental concentrations were also determined using the Inductively Coupled Plasma (ICP-OES) analysis that shows the major elements Ca > Fe > Mg > Al > Mn for all locations, whereas the heavy metals differ as Ni > Cr > Zn > Co > Pb, Cr > Ni > Zn > Pb > Co and Zn > Pb > Cr > Ni, respectively. The correlation between the major elements and heavy metals were also performed using the Pearson Correlation analysis via IBM SPSS which showed the positive Al–Fe–Mn correlation with the heavy metals but negative correlation with Ca. The correlations between the elements were influenced by the adsorption and precipitation of the major minerals in the sediment. The objective of this study is to determine the geochemical distribution of metals due to the influence of minerals in the coastal sediment of Kota Belud, Kudat and Mantanani Island. Therefore, this study could serve as a geochemical baseline data to understand the abundance of metals from the coastal region of northwest Sabah, Malaysia.

Xianzhi Lu, Peiyao Lu, Yingjie Chen et al.

The process mineralogy of an ilmenite in Yunnan Province was studied. The results showed that the grade of titanium in the ore sample was 5.62%. The main metal minerals in the ore were ilmenite and vanadium ilmenite, which occupied for 61.39% and 11.03% of the total titanium, respectively. The gangue minerals were plagioclase and titanaugite. The contents of SiO2 and Al2O3 were 42.35% and 12.53%, respectively. Most of the coarse ilmenite minerals in the samples were closely associated with vanadium ilmenite, sphene and silicate. Meanwhile, the particle size of the aggregation was mainly concentrated in 0.02～0.30 mm, whereas, 27.58% of titanium occurred in sphene and silicate minerals. Exploratory experimental results of low intensity-high intensity magnetic separation indicated that the strong magnetic minerals could be recovered and plenty of gangue minerals could be removed effectively, resulting in the concentration of ilmenite minerals. Thus, the ore belonged to a low grade refractory ilmenite and it will be significant importance to recover the ilmenite effectively for the exploitation and utilization of this resource.

E. Kolesnikov, I. Kupenko, M. Achorner et al.

Elastic anisotropy of iron-bearing alloys and compounds can lead to a variation of seismic velocities along different directions in planetary cores. Understanding the deformation properties of candidate core-forming materials is thus necessary to reveal the details about the interior of distant planets. Silicon has been considered to be one of the dominant light elements in the cores. Here we investigated the deformation of the ε-FeSi phase up to 49 GPa and 1100 K employing the radial X-ray diffraction technique in diamond anvil cells. Stoichiometric FeSi is a good approximation for the deformation behavior of the Fe-FeSi system and the low-pressure polymorph of FeSi may be the stable phase in the cores of small terrestrial planets such as Mercury. Yield strength in ε-FeSi is higher than in hcp-Fe and hcp-Fe-Si alloys, in the temperature range we investigated here the temperature has little influence on the lattice strain parameters, yield strength, and anisotropy within experimental precision. The azimuthal anisotropy of the longitudinal sound waves in ε-FeSi is below 0.6% at low pressure and decreases further with compression, while the shear wave contrast is below 1.25% in the entire investigated pressure range. Therefore, polycrystalline aggregates of iron silicide are nearly isotropic at extreme conditions. Consequently, any observed anisotropy in planetary cores will be incompatible with silicon being the dominant light element in the core composition.

N. P. Pokhilenko, V. P. Afanasiev, A. M. Agashev et al.

We discuss herein the differences both in composition and structure of the lithospheric mantle of the Siberian Platform under kimberlite fields of different ages. Having analyzed the pyrope garnets from kimberlites of different ages this study aimed to identify the genesis, extent and probable causes for the evolution of the composition and structure of the lithospheric mantle within various SP blocks. Acquired results revealed noticeable differences in the lithosphere thickness of different blocks for Middle Paleozoic and Mesozoic, as well as within the same time. It was found, that the greatest differences in the thickness of the lithosphere individual blocks are typical for the Middle Paleozoic. The results obtained for pyrope garnets from the Paleozoic sedimentary secondary collectors was used to get direct evidence on the existence of thick lithosphere blocks (230–240 km) under the southern margin of the Olenek uplift, north and south of the Kyutyungde trough, as well as under the western and eastern margins of the Udzhinsky uplift. Significant variations in the intensity and extent of silicate-type metasomatism were identified by investigating of pyropes from peridotites of the lithospheric mantle, sampled by kimberlites of both Middle Paleozoic and Triassic fields. Direct evidence indicates high prospects for discovering new fields of diamondiferous high-grade kimberlites of the Middle Paleozoic age in some areas of the Siberian Platform, primarily in its Arctic region.

I. V. Karmysheva, V. A. Yakovlev, A. M. Sugorakova et al.

Based on the isotope-geochronological (zircons, U-Pb method), petrogeochemical, and structural and petrologic data, the following paper provides a detailed description of the characteristics of the Late Paleozoic basic and granitoid magmatism in the eastern part of the Kaakhem magmatic area (Eastern Tuva). During the formation of the Shivey alkaline-granitoid and Chadal gabbroid massifs in the period of 292–283 Ma, there were revealed two stages of contrasting magmatism. The early stage is characterized by the formation of plutonic mingling structures and intermediate rocks. Deformation structures, widespread in the early-mingling rocks, are superimposed and formed in extensional regime. At a later stage, there occurred a sequential intrusion of salic and mafic magmas into the zones of local extension in the early-mingling host rocks. A similar petrogeochemical composition of basic rocks of the early and late mingling indicates that they all formed from enriched magma. Granosyenites and granites are derived from melting of tonalities and metasedimentary rocks with a significant contribution of the mantle component. The simultaneous formation of the Chadal gabbroid and Shivei granitoid massifs took place at the intraplate stage of the development of geological structures of Eastern Tuva in the Late Paleozoic.

Erdinç Öksüm, Şakir Şahin

The East Anatolian Fault Zone (EAFZ) is one the main tectonic elements of Turkey, which borders the Anatolian plate from the east. EAFZ, which is NE-SW direction, consists of many fault segments. In the historical and instrumental period, many damaging earthquakes occurred, the largest being 6.8 (Ms) as the 1971 Bingöl earthquake. The last magnitude 6.6 (Ml) (Mw = 6.8) earthquake occurred on January 24, 2020 in Elazığ - Sivrice Hazar - Sincik segment of EAFZ. However, considering the historical and instrumental activity, it is seen that many fault segments are silent. In this study, the silent and active segments, and their seismic velocity (as % Vp and Vp) and attenuation pattern (as Q-1 p) are determined in order to determine the earthquake behavior of EAFZ in the near future. From the results obtained by using the data of the earthquakes that occurred from 2007 to the end of 2019, it was clearly determined that the velocity and attenuation increased on the Hazar - Sincik segment. It has been determined that Vp is 4.08-8.2 km/sec, Q-1 p is ± 0.005 and the frequency dependency varies between 0 - 1.08 along the zone. The variation of velocity and attenuation on the segments where the earthquake occurred and in the silent section were revealed.

Syed Asim Hussain, Syed Asim Hussain, Syed Asim Hussain et al.

The Kohat Basin (KB) lies on the Himalayan Foothills and is of scientific importance as it directly recorded the closure of the Tethys Sea and the Himalayan collision between India, Asia, and a number of other small plates. During the Eocene, after the collision between the Indian and Eurasian plates terminated the Tethys Sea, thick-bedded marine evaporite sequences developed in the KB. In this study, we combined mineralogy, geochemistry, fluid inclusion and chlorine stable isotope compositions to discuss the origin and evolution of the KB Eocene halite deposits with the ultimate objective of defining the paleoclimate that was prevailing in Asia during the Eocene. Our results showed that halite samples were SO42− rich (225–370.103 ppm) and Br− poor (<3 ppm). Cl−, B+, Mg2+, K+, SO42− and very low Br concentrations as well as the (Br/Cl) ratios indicated that halite resulted of a mixture of solutions with variable compositions and that dissolution, recrystallization and a progressive decrease in dolomitization were the mechanisms leading to the formation of these evaporites. A Br/Cl vs Cl plot revealed that the end members involved were: seawater (sw), saline waters and/or freshwaters. The recrystallization process prevented identifying the primary structures and primary fluid-inclusions. Most of Cl isotope compositions (−0.54‰<δ37Cl < 0.83‰) were within the usual range (0 ± 0.5‰) associated to seawater as the initial source for the halite. The higher isotope compositions (δ37Cl ≥ 0.83‰) comforted the hypothesis of the genesis by mixing of solutions of different origins as well as the involvement of recrystallization. Based on our results, we are proposing the following to explain the regional paleoclimate sequence: 1) shallow water conditions; 2) halite precipitation induced by evaporation, 3) unstable paleoclimatic conditions that resulted in the morphing from an evaporite basin into a terrestrial foreland basin. All these events were controlled by regional tectonic and linked to both the overall uplift times of the NW Indian Craton and the Eocene thermal maximum one during the Eocene-Oligocene period.

Espinoza D. Nicolas

Unconventional oil and gas resources have transformed the energy industry in the United States. Likewise, other countries have followed up with hydrocarbon exploitation from tight unconventional formations. One of the most developed unconventional fields outside North America is the Vaca Muerta Formation in the Neuquén Basin, Argentina. This study summarizes experimental results of quasi-static loading and elastic wave propagation in rocks from the Vaca Muerta Formation along the entire producing interval. The work summarizes experimental results from our laboratory and from the literature. The results highlight the variability of mechanical properties with mineralogy and composition, and the mechanical anisotropy induced by layering. The discussion section explores the implications of spatial variability and anisotropy on in-situ stresses and fluid-driven fractures. Accurate characterization of rock mechanical properties is critical for predicting the geometry of fluid-driven fractures in unconventional rock formations, particularly those subjected to a tectonically active environment such as the Vaca Muerta Formation.

Mihaela Glamoclija, Steven Ramirez, Kosala Sirisena et al.

The hypersaline sediment and groundwater of playa lake, Lake Lucero, at the White Sands National Monument in New Mexico were examined for microbial community composition, geochemical gradients, and mineralogy during the dry season along a meter and a half depth profile of the sediment vs. the groundwater interface. Lake Lucero is a highly dynamic environment, strongly characterized by the capillary action of the groundwater, the extreme seasonality of the climate, and the hypersalinity. Sediments are predominantly composed of gypsum with minor quartz, thenardite, halite, quartz, epsomite, celestine, and clays. Geochemical analysis has revealed the predominance of nitrates over ammonium in all of the analyzed samples, indicating oxygenated conditions throughout the sediment column and in groundwater. Conversely, the microbial communities are primarily aerobic, gram-negative, and are largely characterized by their survival adaptations. Halophiles and oligotrophs are ubiquitous for all the samples. The very diverse communities contain methanogens, phototrophs, heterotrophs, saprophytes, ammonia-oxidizers, sulfur-oxidizers, sulfate-reducers, iron-reducers, and nitrifiers. The microbial diversity varied significantly between groundwater and sediment samples as their temperature adaptation inferences that revealed potential psychrophiles inhabiting the groundwater and thermophiles and mesophiles being present in the sediment. The dynamism of this environment manifests in the relatively even character of the sediment hosted microbial communities, where significant taxonomic distinctions were observed. Therefore, sediment and groundwater substrates are considered as separate ecological entities. We hope that the variety of the discussed playa environments and the microorganisms may be considered a useful terrestrial analog providing valuable information to aid future astrobiological explorations.

Engin MERİÇ, İpek F. BARUT, Atike NAZİK et al.

Bu çalışma, Kuşadası Körfezi’nin kuzey ucunu oluşturan Doğanbey Burnu’nun kıyı alanındaki farklı noktalarda bulunan deniziçi sıcak su çıkışlarının, yakın çevrede yaşamını sürdüren çeşitli mikro ve makrofauna toplulukları üzerindeki etkisini araştırmak amacıyla yapılmıştır. Doğanbey Burnu’nun güneydoğusunda farklı derinliklerde 15 noktadan kepçe ile genç çökel örnekleri alınıp, bunların içermiş olduğu bentik foraminifer, ostrakod ve mollusk faunası değerlendirilmiştir. Bentik foraminiferler 35 cins, 61 tür, ostrakodlar 16 cins 20 tür, gastropodlar 14 cins ve 18 tür, bivalvler ise 14 cins ve 15 tür olarak bulunmuştur.. Ayrıca çalışma alanında, Ege kıyılarında sıkça rastlanılan foraminifer kavkılarındaki renklenme, şekil bozukluğu ile göçmen bentik foraminiferlerin varlığı tespit edilmiştir. Çalışılan bölgede tanımlanan foraminifer, ostrakod ve mollusk faunası tipik Ege faunasına paralellik sunmaktadır. Tipik Ege bentik foraminifer topluluğu içindeki Amphistegina lobifera Larsen bireylerinin yaşadığı ekolojik koşullarının bolluk dağılımı üzerinde etkisi bilinmektedir. Bölge için Amphistegina lobifera Larsen’nın ideal yaşam aralığı 18.00-32.00 m derinlik ve yaklaşık 19-20o C sıcaklık olarak belirlenmiştir. Bir diğer özellik olarak CTD cihazı ile yapılan ölçümlerde iletkenlik değerlerinin sıcak su kaynağına yaklaştıkça arttığı ancak birey sayısının azaldığı tespit edilmiştir. Sediment örneklerinde kimyasal analizler X-Işını Floresans Analiz Spektrometresi (WDXRF) ile yapılmıştır. Sediment örneklerinde ağır metallerden Cr, Mn, Co, Ni, Cu, Zn ve Pb değerlerine bakılmış, bu değerlerin. DB1-DB6 arası örneklerde ve DB15 de Cr>Ni>Mn, DB8-DB11 arası örnekler ile DB13 ve DB14 de Mn>Cr>Ni, DB7 ve DB12 de Cr>Mn>Ni, olduğu tespit edilmiştir. Radyoaktif elementlerden U ve Th DB9, DB10 ve DB11 de yüksek değerdedir. Eser elementlerden Sr değeri DB7-DB11 arası örneklerde yüksektir. Sedimentlerin kimyasal ve radyoaktif özelliklerinin bentik foraminifer kavkılarında etkisi gözlenirken ostrakod ve mollusk kavkılarında herhangi bir etki belirlenmemiştir.

T P Mangan, J D Atkinson, J W Neuberg et al.

Fine particles of ash emitted during volcanic eruptions may sporadically influence cloud properties on a regional or global scale as well as influencing the dynamics of volcanic clouds and the subsequent dispersion of volcanic aerosol and gases. It has been shown that volcanic ash can trigger ice nucleation, but ash from relatively few volcanoes has been studied for its ice nucleating ability. In this study we quantify the efficiency with which ash from the Soufriere Hills volcano on Montserrat nucleates ice when immersed in supercooled water droplets. Using an ash sample from the 11th February 2010 eruption, we report ice nucleating efficiencies from 246 to 265 K. This wide range of temperatures was achieved using two separate droplet freezing instruments, one employing nanolitre droplets, the other using microlitre droplets. Soufriere Hills volcanic ash was significantly more efficient than all other ash samples that have been previously examined. At present the reasons for these differences are not understood, but may be related to mineralogy, amorphous content and surface chemistry.

Arezoo Moradi, Nahid Shabanian Boroujeni , Ali Reza Davoudian Dehkordy

Introduction Studied mylonitic granite-gneiss body is located in the Northwest of the Azna region in the Lorestan province close to the June dimension stone mine. It is a part of the metamorphic- magmatic complex including granite-gneiss, amphibolite, marble and schist. The crystalline basement is attributed to late-Neoproterozoic and it indicates a Panafrican basement, which yields a laser-ablation ICP–MS U–Pb zircon ages of 608 ± 18 Ma and 588 ± 41 Ma (Shakerardakani et al., 2015). There are two granite-gneiss plutons in the complex that are Galeh– Dezh (Shabanian et al., 2009), and June plutons. The Galeh-Doz pluton are previously proposed as syn-deformation pluton with a major S-shaped bend which has been imparted during dextral shearing with a Late Cretaceous (Mohajjel and Fergusson, 2000). However, new age dating on the pluton using U–Pb in the magmatic zircon produced the late-Neoproterozoic dates (Nutman et al., 2014; Shakerardakani et al., 2015). The granite-gneiss plutons show mylonitic fabrics and microstructures (Shabanian et al., 2010). The geochemical characteristics of mylonitic granite-gneiss body near June mine in NW Azna, is in the focus of our research. Materials and methods Petrographic investigations of 30 thin sections were made. Then eight samples were selected and analyzed for whole rock major, trace and REE compositions by ICP-emission spectrometry and ICP-mass spectrometry using natural rock standards as reference samples for calibration at the ACME Analytical Laboratories in Vancouver, British Columbia, Canada. Results The studied gneiss- granitic body has lepido-granoblastic texture as its major texture. It variably shows evidence of dynamic deformation from ultramylonite to protomylonite. The gneiss- granite consists of quartz, alkali feldspar (mostly as perthite), plagioclase, biotite, white mica (muscovite and phengitic muscovite). Accessory phases in the granitoid include, tourmaline, zircon, magmatic epidote, allanite, apatite, and magnetite. The mylonitic gneiss-granite has a mantled porphyroclast texture that may be characterized by large asymmetrical porphyroclasts of K-feldspar and plagioclase with a mantle which includes white-mica, biotite, quartz and feldspar aggregates. Some of the petrographic evidence show dynamic deformation during the crystallization such as grain boundary migration (GBM) or sub-grain rotation (SGR), patchy perthite. Evidence of strain, such as deformation twins, bent or curved twins, undulatory extinction occur characteristically in plagioclase and display dynamic deformation in solid state. The rocks exhibit identical compositional ranges with 71.24–78.35 wt.% SiO2; high levels of alkalies (Na2O ranges from 3.07 to 4.02 %, K2O varies from 4.18 to 5.53 %); low levels of Fe2O3tot (0.80 to 2.60 %). Also, the trace element compositions display significant variations, such as Zr (157.7-330.5 ppm), Eu (0.07-0.28 ppm), Nb (40.9-77.3 ppm), Ga (19.7-25.97 ppm). The studied rocks are strongly enriched in LREE and HFSE and show a strong depletion in Ba, Sr, Eu and Ti and enrichment in Rb and Zr. The element contents are also similar to typical A-type granite (Whalen et al., 1987). The rocks are alkali to alkali-calcic, metaluminous to mildly peraluminous granite and ferroan in new geochemical classification scheme for granitoids (proposed by Frost et al., 2001). Discussion The chondrite-normalized rare-earth element patterns of the mylonitic gneiss- granitic rocks indicate the LREE over HREE fractionation with significant negative Eu anomalies. Primitive-mantle-normalized spidergrams (Sun and McDonough, 1989) normalized trace element patterns with negative Ba and Nb anomalies, and positive Rb, Th and Ce anomalies, simulate the collisional and post-collisional granitoids of Pearce et al (Pearce et al., 1984). All of the samples fall in the A2 group in Eby classification (Eby, 1992). On the tectonic discrimination plots, the granites show a within-plate granite (WPG) character (Pearce et al., 1984). Acknowledgements The study was completed at the Shahrekord University and it was supported by the office of graduate studies. The authors are grateful to the office for their support. References Eby, G.N., 1992. Chemical subdivision of the A-type granitoids: petrogenetic and tectonic implications. Chemical Geology, 20(7): 641–644. Mohajjel, M. and Fergusson, C.L., 2000. Dextral transpression in Late Cretaceous continental collision, Sanandaj–Sirjan Zone, western Iran. Journal of Structural Geology, 22(8): 1125-1139. Nutman, A.P., Mohajjel, M., Bennett, V.C. and Fergusson, C.L., 2014. Gondwanan Eoarchean Neoproterozoic ancient crustal material in Iran and Turkey: zircon U–Pb–Hf isotopic evidence1. Canadian Journal of Earth Sciences, 51(3): 272–285. Pearce, J.A., Harris, N.W. and Tindle, A.G., 1984. Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. Journal of Petrology, 25(4): 956–983. Shabanian, N., Davoudian, A.R., Khalili, M. and Khodami, M., 2010. Texture evidences imply on dynamic conditions in late-stage to post magmatic crystallization from dynamo-magmatic gnessies of Ghaleh-Dezh, Azna. Iranian Society of Crystallography and Mineralogy, 18(3): 463-472. (in Persian with English abstract) Shabanian, N., Khalili, M., Davoudian, A.R. and Mohajjel, M., 2009. Petrography and geochemistry of mylonitic granite from Ghaleh-Dezh, NW Azna, Sanandaj-Sirjan Zone, Iran. Neues Jahrbuch Fur Mineralogie-Abhandlungen, 185(3): 233-248. Shakerardakani, F., Neubauer, F., Masoudi, F., Mehrabi, B., Liu, X., Dong, Y., Mohajjel, M., Monfaredi, B. and Friedl, G., 2015. Panafrican basement and Mesozoic gabbro in the Zagros orogenic belt in the Dorud–Azna region (NWIran): Laser-ablation ICP–MS zircon ages and geochemistry. Tectonophysics, 647–648: 146–171. Sun, S.S. and McDonough, W.E., 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In: A.D. Saunders and M.J. Norry (Editor), Magmatism in the Ocean Basins. Geological Society 42, London, pp. 313–345. Whalen, J.B., Currie, K.L. and Chappell, B.W., 1987. A-type granites: geochemical characteristics, discrimination and petrogenesis. Contributions to Mineralogy and Petrology, 95(4): 407–419.

Kate Tungpalan, Elaine M. Wightman, Emmy Manlapig

Gerhard Laus, Volker Kahlenberg, Herwig Schottenberger

5-Azido-4-(dimethylamino)-1-methyl-1,2,4-triazolium hexafluoridophosphate was synthesized from the corresponding 5-bromo compound with NaN3. Reaction with bicyclo[2.2.1]hept-2-ene yielded a tricyclic aziridine, addition of an N-heterocyclic carbene resulted in a triazatrimethine cyanine, and reduction with triphenylphosphane gave the 5-amino derivative. The crystal structures of three nitrogen-rich salts were determined. Thermoanalysis of the cationic azide and triazene showed exothermal decomposition. The triazene exhibited negative solvatochromism in polar solvents involving the dipolarity π* and hydrogen-bond donor acidity α of the solvent.