opaque minerals
Recently Published Documents


TOTAL DOCUMENTS

154
(FIVE YEARS 28)

H-INDEX

15
(FIVE YEARS 1)

2022 ◽  
Vol 19 (2) ◽  
pp. 2016
Author(s):  
Burapha Phajuy ◽  
Vimoltip Singtuen

One of the oldest lime manufactures in Chiang Mai Province is located in a hillside village, Ban Pong, Hang Dong District, the western part of Chiang Mai City. Villagers still have conserved traditional production methods using wood-fired kilns and the primary material selection, an Ordovician marble. There are 2 massive amounts of carbonate rocks distributed in Chiang Mai Province; Permian limestone and Ordovician marble. However, the Ordovician carbonate rocks in Ban Pong were selected to produce high-quality lime by their primitive method (man-made) for a long time. Petrographical studies suggest that the Ordovician rock samples show a granoblastic texture with a slightly foliation represents by mica flakes. They are made up mainly of calcite, with very small amounts of quartz, muscovite, talc, and opaque minerals that can be identified as marble. The mineral compositions are according to the value of CaO, SiO2, Al2O3, K2O, and Fe2O3 in whole-rock analysis by XRF. The geochemical data suggest that marble in the Ban Pong area has a high CaO ratio and contains small amounts of muscovite, quartz, talc, and opaque minerals that may reduce the decomposition temperature during the calcination process. The Ordovician marble in Ban Pong is an appropriate raw material for traditional lime manufacture to saving energy in the production system. HIGHLIGHTS Limestone has been a geologic material in the lime industry from the past to the presence of human society Villagers in Ban Pong (Chiang Mai Province, Thailand) selected the western Ordovician limestone mountains to produce lime by a primitive process instead of the eastern Permian limestone mountains The mineral- and chemical compositions of the Ordovician limestones were intensively analyzed to characterize the suitable raw materials for a primitive lime kiln The mineral composition indicated that the Ordovician limestone in this area is metamorphosed into an impure fine-grained marble GRAPHICAL ABSTRACT


Atmosphere ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1385
Author(s):  
Hannan Younis ◽  
Farooq Ahmad ◽  
Ramoona Shehzadi ◽  
Ishrat Asghar ◽  
Tanveer Ahmad ◽  
...  

Radioactivity in Granites of Pakistan systematically increases from south to north. The Ambella Granite found at the northern edge of Pakistan is highly radioactive. Radioactivity measurements made on, so called, Bajaur Granite, located in northern Pakistan, have been found to be lowest among all the granitic rock of the area. In order to find out the exact nature of Bajaur rocks, mineralogical studies were carried on rock chips and powdered samples. The Bajaur Norite contains plagioclase feldspar more than 45% as the chief constituent. Orthopyroxene and clinopyroxene are 27% and 18%. Quartz, biotite, and some opaque minerals are also found in accessory amounts. Bajaur Granite is in fact not a granite but Norite, which is rich in Na-Ca plagioclase series of feldspars. The plagioclase feldspar rich in Na-Ca are low in radioactivity. Moreover, the average gamma activities of 226Ra, 232Th, and 40K (4.98 ± 0.13 Bqkg−1, 4.03 ± 0.31 Bqkg−1, 204.40 ± 4.72 Bqkg−1 and a total of all three radionuclides are 214.00 ± 5.39 Bqkg−1) for Bajaur Norites are found too be much less than the average of the world’s Granites. Indoor and outdoor hazard indices of Bajaur Norite are much below building materials used throughout the world and largely beneath their criterion restrictions. As per radiations’ hazards are concerned, the Bajaur Norite as a building stone may be considered as the safest material available in the area that does not pose any radiological hazard.


Author(s):  
Hafiz Muhammad Zulfiqar Ali ◽  
Muhammad lrfan Zubair ◽  
Hassan Ali ◽  
Ghulam Akbar ◽  
Adnan Alam Awan

Present research exertion provides the information about the stratigraphy, geological structure, geochemistry and petrographic characteristics of the exposed sedimentary rock units and igneous intrusions around Zhob and Qila Saifullah districts of Balochistan. Sedimentary deposition in this area is attribute to both Pashin basin and Suleiman basin. The litho-stratigraphic sections of Suleiman basin are Spingwar formation and Loralai formation (Allozai Group) of Jurassic age and Goru formation, Parh limestone and Pab sandstone of Cretaceous age, whereas Pashin basin comprises of Nisai formation of Eocene age and Multana formation of 0ligocene - Miocene age. The structural features of the area are comprising of complex, doubly plunging, anticlines and synclines which have been truncated by reverse faults at different places.Geochemical analysis (X-Ray diffraction and X-Ray fluorescence) displays that Igneous Intrusions are comprising of Clay, Mica, Plagioclase and Spinal mineral with abundance of Al203 (11-14% wt.), Si02 (27-34 % wt.), Ca0 (6-17% wt.) and Fe203 (19-32% wt.), whereas sedimentary rocks are rich in Quartz, Calcite and Albite with abundance of Al203 (0-17% wt.), Si02 (1.35-78% wt.), Ca0 (0.92-55% wt.) and Fe203  (0.07-13% wt.). The petrographic studies of the carbonates indicate mudstone to wackstone, carbonate fabric with skeletal grains of Alveolina, Miliolids, Globotrancana, Algae, Stylolites and foraminifera, whereas the sandstone samples are rich in sub rounded to rounded quartz grain, feldspar and mica. Petrographic analysis of igneous intrusion shows muscovite, pyroxene needles, chlorite and opaque minerals. Economically the research area is appropriate for cement factory, glass industry and building stones.  


2021 ◽  
Vol 37 (4) ◽  
pp. 380-390
Author(s):  
Jae Hwan Kim ◽  
Min Su Han

The purpose of this study is to scientifically analyze the rocks of the Obongsan Mountain in Boseong, Jeollanam-do, which contains the largest extant quarry of Gudlejang (flat stone for heating) in Korea, and to scientifically determine the petrological characteristics of the area and the reasons for its use as a quarry. The rocks in the quarry are composed of light-green lapilli tuff, containing various types of lithic fragments and crystalline fragments in a vitreous matrix consisting of the fine feldspar crystals. The main constituent minerals were identified as quartz, plagioclase, mica, chlorite and opaque minerals. When the major element compositions were plotted on a Na2O+K2O versus SiO2 diagram, all samples were situated in the same compositional area as rhyolite. In addition, the result of magnetic susceptibility measurement also showed a similar range of values, of 1.30 ∼ 4.85 (×10<sup>-3</sup> SI), indicating that samples were fractionated from the same magma. Both rock types showed similar apparent specific gravity values of 2.32 ~ 2.60. In particular, plate-shaped joints are well developed in the Obongsan Mountain area, and many areas exhibit talus terrain. In conclusion, the rocks of this area is interpreted to used for a site of Gudlejang quarrying, because the rocks were easily obtainable due to the terrain characteristics, and their petrological properties made them suitable for use as Gudlejang stone.


2021 ◽  
Vol 8 ◽  
Author(s):  
Song Mao ◽  
Qin Zhang

Anode carbon residue is produced in the production of electrolytic aluminum. Its properties need to be studied for secondary utilization. In this paper, mineralogy of anode carbon residue from an electrolytic aluminum plant in Guizhou was studied. The anode residue chemical composition, structure, mineral composition, occurrence state of main elements, etc, was investigated. The results show that: Anode carbon residue is mainly composed of 14 minerals such as cryolite, cryolithionite, elpasolite and graphite. Among them, the opaque minerals are mainly graphite and the transparent minerals are mainly cryolite. Carbon in the form of independent mineral occurrence in graphite; fluoride in the form of independent mineral occurrence in cryolite, cryolithionite, elpasolite and fluorite; aluminum in the form of independent mineral occurrence in cryolite, cryolithionite, elpasolite, aluminium oxide and magnesium aluminate; sodium in the form of independent mineral occurrence in cryolite, cryolithionite, elpasolite. The mineralogical characteristics and occurrence state of carbon and electrolyte were studied, which provided a basis for the separation and recovery of carbon and electrolyte in anode carbon residue.


2021 ◽  
Vol 170 ◽  
pp. 107007
Author(s):  
Michel Pedro Filippo ◽  
Otávio da Fonseca Martins Gomes ◽  
Gilson Alexandre Ostwald Pedro da Costa ◽  
Guilherme Lucio Abelha Mota

2021 ◽  
Vol 2 (2) ◽  
pp. 33-46
Author(s):  
A. D. Adedoyin ◽  
J. G. Atat ◽  
E. E. Ekott

Petrographic and provenance studies of heavy minerals in Ifelodun sediment were carried out. Sediment samples from eight locations were obtained from the study area; sieved to allow only sand-size lithology. The result was achieved after subjecting this sieved lithology obtained to analyses using a binocular (transmitted and reflected light) microscope. Minerals were separated in a funnel using bromoform with a specific gravity of about 2.89 (gravity method). The heavy minerals present in lithologic sand units are mainly staurolite, tourmaline, zircon and other opaque minerals including cassiterite. The most dominant non-opaque mineral is staurolite with 27.5% of the total minerals counted in the area. Staurolite is very appreciable in locations AR1 with 60% presence (which is 80% of the non-opaque minerals), AR3, AR5, AR7 and OL15b (each with 30%). OL15b also recorded a better amount of tourmaline (20%); Zircon is better in OL6b with 20% of the heavy minerals available in this location. The source rock predicted is porphyroblastic schists.


2021 ◽  
pp. jgs2020-171
Author(s):  
Mutlu Özkan ◽  
Ömer Faruk Çelik ◽  
Andrea Marzoli ◽  
Rahmi Melih Çörtük ◽  
Mehmet Zeki Billor

Unusual carbonate dykes, which have a thickness of up to 4 meters, crosscut the amphibolites from the high-grade metamorphic rocks in the Armutlu Peninsula (NW Turkey). They are described as carbonatites based on their petrographic, geochemical, and isotope-geochemical characteristics. The carbonatites, which show commonly equigranular texture, are composed of calcite and clinopyroxene with other minor phases of plagioclase, mica, garnet, K-feldspar, quartz, epidote, titanite, and opaque minerals. They contain abundant xenoliths of pyroxenite and amphibolite. Geochemical characteristics of the carbonatites are significantly different from those of mantle-derived carbonatites. They have remarkably low incompatible elements (e.g. Ba, Th, Nb) and total REE contents (11-91 ppm) compared to mantle-derived carbonatites. The high 87Sr/86Sr(i) (0.70797-0.70924) and low εNd(t) (-8.08 to -9.57) of the carbonatites confirm that they were derived from the continental crust rather than from a mantle source. Mica from carbonatite was dated by the 40Ar/39Ar method and yielded Late Jurassic – Early Cretaceous (148-137 Ma). This age is significantly younger from the age (Upper Triassic) of adjacent amphibolites. All data from field studies, as well as petrographic, geochemical and geochronological observations, suggest that these carbonatites were formed from the anatectic melting of a carbonated source area in the continental crust.Supplementary material: A complete description of the analytical methods (Whole rock chemistry, mineral chemistry, Strontium and Neodymium isotopes and 40Ar/39Ar measurements) and mineral chemistry and 40Ar-39Ar dating results are available at https://doi.org/ 10.6084/m9.figshare.12946955


2021 ◽  
pp. 1-16
Author(s):  
Mansoor Ahmad ◽  
Abdul Qayoom Paul ◽  
Priyanka Negi ◽  
Salim Akhtar ◽  
Bibhuti Gogoi ◽  
...  

Abstract The Proterozoic Chotanagpur Granite Gneiss Complex (CGGC) at the northern boundary of the Central Indian Tectonic Zone (CITZ) of the eastern Indian shield preserves relics of fossilized oceanic back-arc crust. We describe the field, petrographical and geochemical characteristics of the mafic rocks comprising pillow basalts and dolerites from the Bathani area of the northern fringe of the CGGC, eastern India. The basalts consist of plagioclase feldspar, hornblende, opaque minerals (Fe–Ti oxide) and chlorite, and the dolerite consists of plagioclase, hornblende and opaque minerals. Our data indicate that the Bathani mafic rocks have tholeiitic to transitional composition and are overprinted by greenschist facies metamorphic conditions; however, REE and fluid immobile elements preserve their primary geochemical signatures. The (La/Sm)N ratios (1.38–2.15) and chondrite-normalized REE patterns point to an enriched mid-ocean ridge basalt (E-MORB) mantle source. Geochemical characteristics indicate a mixed signature of MORB and arc tholeiite with enrichment of Ba, Th, Eu and Sr, similar to that of back-arc supra-subduction zone ophiolites. These mafic rocks are the product of MORB-like magma derived from a depleted mantle corresponding to < 2% partial melting of spinel lherzolite, enriched by subduction-induced slab metasomatism and melting. The Bathani mafic rocks are representative of the upper part of a supra-subduction zone columnar ophiolite section, which was emplaced onto the present-day northern margin of the CGGC during suturing of the northern and southern Indian block at c. 1.9 Ga during the Nuna amalgamation.


2021 ◽  
Author(s):  
Alp Ünal ◽  
Şafak Altunkaynak

&lt;p&gt;Bal&amp;#305;kesir Volcanites (BV) are included into the Bal&amp;#305;kesir Volcanic Province and contain various products of Oligo-Miocene volcanic activity in NW Anatolia. BV are formed from trachyandesite, andesite and dacite lavas with associated pyroclastic rocks. In this study, we report the petrographical investigations, mineral chemistry results and geothermobarometry calculations of the Bal&amp;#305;kesir Volcanites in order to deduce the magma chamber processes and crystallization conditions. Andesites present a mineral composition of plagioclase (An35&amp;#8211;50) + amphibole (edenitic hornblende) +biotite &amp;#177; quartz and opaque minerals. The major phenocryst phases in dacite lavas are plagioclase (An39&amp;#8211;53), quartz, amphibole (magnesio-hornblende), biotite, sanidine and opaque minerals. The mineral composition of the trachyandesites, on the other hand, is represented by plagioclase (An38&amp;#8211;57) + amphibole (pargasitic hornblende) + biotite + clinopyroxene (endiopside- augite) &amp;#177; sanidine &amp;#177; quartz &amp;#177; opaque minerals. Bal&amp;#305;kesir Volcanites present distinct textural properties such as rounded plagioclase phenocrysts with reaction rims, oscillatory zoning, honeycomb and sieve textures in plagioclase, reverse mantled biotite and hornblende crystals. The plagioclase- amphibole geothermobarometry calculations of Bal&amp;#305;kesir volcanites indicate that, andesite and dacite lavas present similar crystallization temperature and pressures conditions of 798- 813&amp;#176;C and 1,98- 2.17 kbar. Oppositely, trachyandesites were crystallized under 857&amp;#176;C and 3,72 kbar temperature and pressure conditions. These results show that the andesite and dacite lavas were originated from the same magma chamber with the depth of 7km whereas trachyandesites were evolved in a deeper magma chamber with 13 km depth. Combined mineral chemistry, petrography and geothermobarometry studies indicate that the open system processes such as magma mixing/mingling and/or assimilation fractional crystallization (AFC) were responsible for the textural and compositional variations of the Bal&amp;#305;kesir Volcanites.&lt;/p&gt;


Sign in / Sign up

Export Citation Format

Share Document