Geological-Structural Setting of Massif and the Levels of Quartz - Sulphide M...IJERA Editor
Kaptina gabbro massif is placed in the northern half of the eastern Mirdita ophiolitic belt and is spreaded in a relatively large area. Petrology of Kaptina gabbro massif is very complicated as in view of the diversity of rocks that are spreaded within it as well in view of structurally construction. In this region are exposed all components of the Mirdita ophiolitic Complex, as well as oceanic sedimentary cover, the Cretaceous one and the newer mollasic formations of Pliocene-Quaternary. Kaptina gabbro massif has an irregular shape, however is seen a certain extension in the meridional - submeridional direction. This massif is plunged in the South and the West under volcanogenic formations to come back in the small output in the lower Bisaku and to join more south with the Bulshari gabbro massif. The outputs of massif are expanded towards the north - northeast. In construction of gabbro massif take part a range of rocky types that stay in various reports regarding surface spreading. Greater spreading in all the massif have gabbronorite, in close connection with them stay norite and gabbro.
Exploration in Deep Weathering Profiles, Supergene, R-mode factor analysis; Multi-element association geochemistry; Assessment of Au-Zn potentiality in Gossan; Rodruin-Egypt
Geological and Geochemical Characterization of the Neoproterozoic Derudieb Me...Premier Publishers
The meta- volcano - sedimentary sequences in the northern part of the Red Sea Hills comprise a sequence of metamorphosed rocks at low green schist facies of metamorphism consisting of lava flows, tuffs to breccias and agglomerates range in composition from basalts and andesites to rhyolites. Geologically the meta volcano sedimentary sequences is divided into metavolcanic rocks and metasediments. The metavolcanic rocks range in composition from mafic to felsic. The metasediments are represented by banded schist, quartzite and marble. The samples collected for study lie within the field of sub-alkaline rocks except one mafic volcanic sample, which plot near the boundary in the alkaline field and thus follow a transitional tholeiitic to calc-alkaline trend (increasing FeO* relative to MgO). The behavior of the large ion lithophile element (LILE) in the studied metavolcanics confirms the early fractionation of plagioclase. These rocks display negative Nb anomalies, suggesting that the melt source was modified by subduction-related fluids. Tectonically all felsic samples fall in the field of volcanic arc granitoids whereas the mafic units plot firmly within the plate margin field.
Grossular bearing jadeite omphacite rock in the myanmar jadeite areaYMCA Mandalay
The Myanmar jadeitite deposits near Hpakant have attracted remarkable attention of geologists and gemologists not only for being the largest jadeite jade deposit in the world, producing high quality jade with the glassy imperial green for more then 300 years.
Geological-Structural Setting of Massif and the Levels of Quartz - Sulphide M...IJERA Editor
Kaptina gabbro massif is placed in the northern half of the eastern Mirdita ophiolitic belt and is spreaded in a relatively large area. Petrology of Kaptina gabbro massif is very complicated as in view of the diversity of rocks that are spreaded within it as well in view of structurally construction. In this region are exposed all components of the Mirdita ophiolitic Complex, as well as oceanic sedimentary cover, the Cretaceous one and the newer mollasic formations of Pliocene-Quaternary. Kaptina gabbro massif has an irregular shape, however is seen a certain extension in the meridional - submeridional direction. This massif is plunged in the South and the West under volcanogenic formations to come back in the small output in the lower Bisaku and to join more south with the Bulshari gabbro massif. The outputs of massif are expanded towards the north - northeast. In construction of gabbro massif take part a range of rocky types that stay in various reports regarding surface spreading. Greater spreading in all the massif have gabbronorite, in close connection with them stay norite and gabbro.
Exploration in Deep Weathering Profiles, Supergene, R-mode factor analysis; Multi-element association geochemistry; Assessment of Au-Zn potentiality in Gossan; Rodruin-Egypt
Geological and Geochemical Characterization of the Neoproterozoic Derudieb Me...Premier Publishers
The meta- volcano - sedimentary sequences in the northern part of the Red Sea Hills comprise a sequence of metamorphosed rocks at low green schist facies of metamorphism consisting of lava flows, tuffs to breccias and agglomerates range in composition from basalts and andesites to rhyolites. Geologically the meta volcano sedimentary sequences is divided into metavolcanic rocks and metasediments. The metavolcanic rocks range in composition from mafic to felsic. The metasediments are represented by banded schist, quartzite and marble. The samples collected for study lie within the field of sub-alkaline rocks except one mafic volcanic sample, which plot near the boundary in the alkaline field and thus follow a transitional tholeiitic to calc-alkaline trend (increasing FeO* relative to MgO). The behavior of the large ion lithophile element (LILE) in the studied metavolcanics confirms the early fractionation of plagioclase. These rocks display negative Nb anomalies, suggesting that the melt source was modified by subduction-related fluids. Tectonically all felsic samples fall in the field of volcanic arc granitoids whereas the mafic units plot firmly within the plate margin field.
Grossular bearing jadeite omphacite rock in the myanmar jadeite areaYMCA Mandalay
The Myanmar jadeitite deposits near Hpakant have attracted remarkable attention of geologists and gemologists not only for being the largest jadeite jade deposit in the world, producing high quality jade with the glassy imperial green for more then 300 years.
The southern Indian granulite terrane is known for granulite - facies rocks which is formed during the ‘Pan-African orogeny.
The region is composed of Neoproterozoic to Cambrian crustal blocks, dissected by large-scale shear zones (Palghat-Cauvery and Achankovil).
The Palghat-Cauvery Shear Zone System (PCSZ), separates the terrane into two parts, Archean Dharwar Craton in the north and the Neoproterozoic Madurai Block in the south.
The southern margin of this block is defined by the Achankovil Shear Zone.
Geology of the study area
The Achankovil Shear Zone (ACSZ) is major lineament of 8-10 km width and >100 km length.
The rocks in the zone display a prominent NW-SE trending foliation with steep dips to southwest.
Estimation of pressure and temperature (P-T) of this lithology was first carried out by Santosh (1987) based on conventional geothermometers and mineral equilibrium, that gave 700-800◦ C at 5.5-7.0 kbar.
Later study done by Nandakumar and Harley (2000) which is slightly higher 925 ± 20◦ C at 6.5-7.0 kbar .
3.1. Grt- Opx- Crd Gneiss
The Grt-Opx-Crd gneiss is a coarse-grained, granulite-facies rock with a probable pelitic protolith.
The mineralogy of a representative sample (KR19-5G1) is plagioclase (30-40%), ortho-pyroxene (20-30%), garnet (10-20%), K-feldspar (10-20%), quartz (5-10%), and cordierite (2-5%) with accessory of biotite, spinel, and sillimanite (Fig. 2a).
Garnet is very coarse-grained (3-6 mm) ,subidioblastic, and contains numerous fine-grained inclusions of sillimanite (0.05-0.2 mm), biotite (0.05-0.4 mm), spinel (0.05-0.1 mm), and quartz (0.05-0.1 mm).
The most significant feature of this rock is the direct contact relation of fine grained spinel and quartz (Spl + Qtz), which occur only as inclusions in garnet.
Spl + Qtz association has been regarded as one of the indicators for decompression at UHT conditions. This is the first finding of such an assemblage from the ACSZ.
Heavy Mineral Studies of Beach Sands of Vagathor, North Goa, IndiaIJMER
Vagator beach is situated 22 km away from panjim on the northern side Bardez taluk
approachable via Candolim are Mapusa by road. The beach is projected on both the sides by
promontories. The beach is in arcuate shape, the area included with survey of India toposheet No
48/E/14 which is bounded by latitudes 15º35ˈN 15º38ˈN and longitude 78º43ˈE. The Chapora river
and its tributaries drain the entire region that is the Vagator beach. It flows from North-East to
South-West direction. The drainage pattern is structurally controlled; the Chapora River has its
source in the Ramghat hills of Belgaum district in Karnataka then it flows through the Thilari ghat
and enters Goa. Its length in Goa is about 31 km and the mouth of the river bank, mud bank and
mangroves swamps are common.
In laboratory techniques heavy mineral separation are based mass separation in a liquid
with specific gravity and magnetic separation using hand magnet and Frantz isodynamic separator
at different volts. X-ray analysis was carried out by using RIGAKU ALTIMA IV copper target on the
basis of Bragg’s law. The non magnetic sand grains was observed under optical microscope to
identify diagnostic properties of minerals.
The heavy mineral shoot comprises of opaque (magnetite and illmenite) and transparent heavy
minerals like hornblende, epidote, garnet, rutile, zircon, enstatite and minor amounts of tourmaline.
The light minerals are mainly quartz and feldspars. The magnetite concentration ranges between 2.01
to 56.86% and Ilmenite between 2.83 to 41.04% and non mangnetics between 1.18 to 44.81%. X ray
diffraction studies and SEM (Scanning electron microscope) studies were employed to study the
mineralogical composition of beach sands of Vagator and detailed investigations are dealt in the
paper.
Lithology, Structure and Geomorphology of the Nagari outliers, Chittoor distr...iosrjce
Nagari Quartzite of the Nallamali Group of the Cuddapah Supergroup occurs as outliers in the
southern end of the Cuddapah basin. These are also called Nagari outliers named after the type area of Nagari
Quartzite. All the Nagari outliers exhibit a sequence of basal conglomerate, grit and quartz arenite/quartzite.
Conglomerate is mature and an oligomictic one with the pebbles of quartzite dominating over the chert, quartz,
jasper and vein quartz with siliceous and ferruginous matrix. The clasts in the southern part of the outlier of Sri
Kalahasti have been subjected to shearing resulting in the elongation of pebbles. The grit unit is similar to
conglomerate in composition, but the grains are sub-rounded to angular, medium to coarse grained and set in a
siliceous matrix. The quartzite unit in the Nagari outliers is predominantly fine grained quartz arenite and
occasionally ferruginous in nature. Fining upward of this sequence can be easily recognised in this unit. There
are a number of mini and intermediate cycles, the former is less than half- a- meter and the latter is up to 1
meter in thickness. The varying thickness of the quartzite in different outliers can be considered as a major
cycle. These outliers reflect 2nd order topography. This also exemplifies one of the fundamental concept of
geomorphology that “lithology and structure control the evolution of land forms” put forward by Woolridge.
The major land forms that are clearly visible, even from a distance are the escarpments and cuestas. The hills
are synclinal in structure and are made up of highly resistant quartzite. The intervening valleys that are
anticlinal have granite in the core. The relative competency has played a major role in carving out the mature
topography. It is evident that the synclinal structure that has developed at the time of formation has been refined
by the subsequent tectonics, resulting in the formation of synclinal hills
PROSPECTING TECHNIQUES AND EXPLORATION FOR COAL AT GSI CAMP AMARWARA, CHINDWARA Shivam Jain
PROSPECTING TECHNIQUES AND EXPLORATION FOR COAL AT GSI CAMP AMARWARA, CHINDWARA
for download...click on this https://dlsharefile.com/file/NzA2YTI2YTYt
https://khabarbabal.online/file/NzA2YTI2YTYt
The southern Indian granulite terrane is known for granulite - facies rocks which is formed during the ‘Pan-African orogeny.
The region is composed of Neoproterozoic to Cambrian crustal blocks, dissected by large-scale shear zones (Palghat-Cauvery and Achankovil).
The Palghat-Cauvery Shear Zone System (PCSZ), separates the terrane into two parts, Archean Dharwar Craton in the north and the Neoproterozoic Madurai Block in the south.
The southern margin of this block is defined by the Achankovil Shear Zone.
Geology of the study area
The Achankovil Shear Zone (ACSZ) is major lineament of 8-10 km width and >100 km length.
The rocks in the zone display a prominent NW-SE trending foliation with steep dips to southwest.
Estimation of pressure and temperature (P-T) of this lithology was first carried out by Santosh (1987) based on conventional geothermometers and mineral equilibrium, that gave 700-800◦ C at 5.5-7.0 kbar.
Later study done by Nandakumar and Harley (2000) which is slightly higher 925 ± 20◦ C at 6.5-7.0 kbar .
3.1. Grt- Opx- Crd Gneiss
The Grt-Opx-Crd gneiss is a coarse-grained, granulite-facies rock with a probable pelitic protolith.
The mineralogy of a representative sample (KR19-5G1) is plagioclase (30-40%), ortho-pyroxene (20-30%), garnet (10-20%), K-feldspar (10-20%), quartz (5-10%), and cordierite (2-5%) with accessory of biotite, spinel, and sillimanite (Fig. 2a).
Garnet is very coarse-grained (3-6 mm) ,subidioblastic, and contains numerous fine-grained inclusions of sillimanite (0.05-0.2 mm), biotite (0.05-0.4 mm), spinel (0.05-0.1 mm), and quartz (0.05-0.1 mm).
The most significant feature of this rock is the direct contact relation of fine grained spinel and quartz (Spl + Qtz), which occur only as inclusions in garnet.
Spl + Qtz association has been regarded as one of the indicators for decompression at UHT conditions. This is the first finding of such an assemblage from the ACSZ.
Heavy Mineral Studies of Beach Sands of Vagathor, North Goa, IndiaIJMER
Vagator beach is situated 22 km away from panjim on the northern side Bardez taluk
approachable via Candolim are Mapusa by road. The beach is projected on both the sides by
promontories. The beach is in arcuate shape, the area included with survey of India toposheet No
48/E/14 which is bounded by latitudes 15º35ˈN 15º38ˈN and longitude 78º43ˈE. The Chapora river
and its tributaries drain the entire region that is the Vagator beach. It flows from North-East to
South-West direction. The drainage pattern is structurally controlled; the Chapora River has its
source in the Ramghat hills of Belgaum district in Karnataka then it flows through the Thilari ghat
and enters Goa. Its length in Goa is about 31 km and the mouth of the river bank, mud bank and
mangroves swamps are common.
In laboratory techniques heavy mineral separation are based mass separation in a liquid
with specific gravity and magnetic separation using hand magnet and Frantz isodynamic separator
at different volts. X-ray analysis was carried out by using RIGAKU ALTIMA IV copper target on the
basis of Bragg’s law. The non magnetic sand grains was observed under optical microscope to
identify diagnostic properties of minerals.
The heavy mineral shoot comprises of opaque (magnetite and illmenite) and transparent heavy
minerals like hornblende, epidote, garnet, rutile, zircon, enstatite and minor amounts of tourmaline.
The light minerals are mainly quartz and feldspars. The magnetite concentration ranges between 2.01
to 56.86% and Ilmenite between 2.83 to 41.04% and non mangnetics between 1.18 to 44.81%. X ray
diffraction studies and SEM (Scanning electron microscope) studies were employed to study the
mineralogical composition of beach sands of Vagator and detailed investigations are dealt in the
paper.
Lithology, Structure and Geomorphology of the Nagari outliers, Chittoor distr...iosrjce
Nagari Quartzite of the Nallamali Group of the Cuddapah Supergroup occurs as outliers in the
southern end of the Cuddapah basin. These are also called Nagari outliers named after the type area of Nagari
Quartzite. All the Nagari outliers exhibit a sequence of basal conglomerate, grit and quartz arenite/quartzite.
Conglomerate is mature and an oligomictic one with the pebbles of quartzite dominating over the chert, quartz,
jasper and vein quartz with siliceous and ferruginous matrix. The clasts in the southern part of the outlier of Sri
Kalahasti have been subjected to shearing resulting in the elongation of pebbles. The grit unit is similar to
conglomerate in composition, but the grains are sub-rounded to angular, medium to coarse grained and set in a
siliceous matrix. The quartzite unit in the Nagari outliers is predominantly fine grained quartz arenite and
occasionally ferruginous in nature. Fining upward of this sequence can be easily recognised in this unit. There
are a number of mini and intermediate cycles, the former is less than half- a- meter and the latter is up to 1
meter in thickness. The varying thickness of the quartzite in different outliers can be considered as a major
cycle. These outliers reflect 2nd order topography. This also exemplifies one of the fundamental concept of
geomorphology that “lithology and structure control the evolution of land forms” put forward by Woolridge.
The major land forms that are clearly visible, even from a distance are the escarpments and cuestas. The hills
are synclinal in structure and are made up of highly resistant quartzite. The intervening valleys that are
anticlinal have granite in the core. The relative competency has played a major role in carving out the mature
topography. It is evident that the synclinal structure that has developed at the time of formation has been refined
by the subsequent tectonics, resulting in the formation of synclinal hills
PROSPECTING TECHNIQUES AND EXPLORATION FOR COAL AT GSI CAMP AMARWARA, CHINDWARA Shivam Jain
PROSPECTING TECHNIQUES AND EXPLORATION FOR COAL AT GSI CAMP AMARWARA, CHINDWARA
for download...click on this https://dlsharefile.com/file/NzA2YTI2YTYt
https://khabarbabal.online/file/NzA2YTI2YTYt
Jabalpur_geology , lithology, economic parts of JabalpurShahWanKhan
The oldest exposed rocks in the region are the Mahakoshal group with ages ranging from Archaean to Paleoproterozoic. These are mainly metamorphic rocks, which are folded, faulted and sheared. The rock types of this group exposed in and around Jabalpur are phyllites, dolomitic marbles, metabasalts and quartzites. here was study and submission of geology around jabalpur area .
The prospecting and mining of base metal in India
dates back to 3000 B.C. All the base metal deposit of India has
surface manifestations in various forms. From 19th century to the
middle of the present century, certain European companies
started a modern phase of base metal exploration and
development. Earlier, the search for base metal was confined to
the close study of surface features. In 1940 ground geophysical
survey work has been introduced in order to search the mineral
deposits. The total world production of lead and zinc metals are
about 3.9 and 11.4 million tonnes respectively in 2009. The
leading producing countries for lead is China (41% of world
production), followed by Australia (15%), USA (10%), Peru (8%)
and Mexico (4%). The Indian production of lead and zinc ore is
7.10 million tonnes in the year 2009-10, it includes 136095 tonnes
of lead concentrate and 1224077 tonnes zinc concentrate. In
India, the Western Indian Craton (Rajasthan) is the main
provider of base metal to the country. It contributes nearly 85%
of the estimated lead and zinc. In Western India Craton, the main
metallotect of lead and zinc from an elongated NE – SW trending
polygon, this covers an area of about 20000 sq. km. It comprises
three metalliferous belts mainly, the Pur-Banera belt, the
Rajpura-Dariba- Bethumni belt, and the Sawar belt and two
metalliferous enclaves namely; the Agucha and the Kayar
enclave.
The 20 km. long crescent shaped, Rajpura-Dariba-Bethumni
belt striking N-S to NNE-SSW. The ancient mining and smelting
activities have been noticed at both ends of the belts. Towards the
southernmost part of the belt, the typical gossan is exposed in the
form of hill. B.C. Gupta, Geological survey of India (G.S.I) first
reported Dariba – Bethumni belt, in the year 1934. The
systematic exploration of the belt was initiated by G.S.I in 1962
and continuing till present. In the Rajpura-Dariba-Bethumni belt
Rajpura and Dariba blocks are under active production since
1983, whereas in the Sindesar Khurd block the production was
started in 2007, under the ownership of Hindustan Zinc Limited
of Vedanta Group. Recently the exploration activity is going on in
the Sonariya Khera block, Chittor block and Bethumni block
under the possession of Hindustan Zinc Limited.
The Wadi Sikait Complex:
A Fertile- Post-Collisionl Granite-Pegmatite Suite, Eastern Desert, Egypt.
The Pan-African, Wadi Sikait Complex (WSC), in the south Eastern Desert of Egypt, is a late-tectonic, subsolvus strongly peraluminous, S-type, post-collisionl granite in the Sikait area that features an unambiguous genetic linkage with a proximal, zoned cluster of Be-, REE- and Nb-Ta bearing pegmatites (Abu Rusheid and Nugrus-Sikait area). The WSC is an arcuate belt of orthogneisses, migmatites and other high-grade metamorphic rocks, which mark the boundary between the central Eastern and the south Eastern Deserts of Egypt. The WSC consists of seven internal units (WSC-1 to -3 and PL-1 to -4) that range from chemically primitive biotite, garnet and sillimanite granites (WSC-1 and –2) to a highly evolved, tourmaline- and muscovite- bearing pegmatite granite facies (PL-1 to –4) locally containing endogenous emerald/beryl, molybdinite and cassiterite. Salient petrochemical attributes include A/CNK molar which varies from 1.15 to 1.75, a wide range of SiO2 (68.7-76.9%), high Al2O3 (14.1-16.0%), low CaO (<2.35%) and FeOt+MgO+TiO2 (0.36-6.62%), and with increasing fractionation, enrichment of Na2O, K2O, B, F, Be, Rb, Ga and Li, and depletion of Ba, Sr, Zr, REE and LREE. Strong fractionation is also revealed by Al/Ga (1370-6789), Ba/Rb (<0.01-12), Ca/Sr (21-201), K/Ba (19-9545), Mg/Li (4.26-1421), Na2O/K2O (0.21-34), (Ce/Yb)CN (0.89-83.25), and Eu/Eu* (<0.05-2.29). REE distribution patterns of rare-element pegmatites are lower in REE contents and flatter with prominent negative Eu anomaly than those of the related granites. The REE concentration and the (Ce/Yb)CN ratio decrease from the WSC-1 and -2 through PL-1 and -2 (fine-grained leucogranite) and PL-3 (pegmatitic leucogranite) to the PL-4 (potassic pegmatites).
Genesis of the strongly peraluminous, S-type granite and the associated rare-element pegmatite in the Sikait-Nugrus area is explained by a complex interplay of petrogenetic processes. Rare-elements and boron were previously concentrated in (wackes and mudstone) pelitic sediments deposited in large basins. These rocks underwent step-wise rock dehydration reactions involving muscovite and biotite, under fluid-absent conditions, and successively released these elements to anatectic melt. Rare-elements and volatiles were progressively concentrated via crystal-melt fractionation, the Harker trends of which were obscured by two stages of extraction of residual melt and by episodic, subsolidus redistribution via base-cation leaching. The late magmatic history of the WSC is marked by widespread exsolution of a volatile-rich phase, dispersion of a rare-element- F-B-Be-rich fluid along shear zones and ensuing emigration of rare-element-rich melt-fluid systems upward from the cupola, which led to the regionally zoned Sikait-Nugrus area
A Petrographical Approach to Study Mineral Phases Paragenesis of Gold Bearing...Premier Publishers
India hosts several world class gold prospects like Kolar Gold Fields (KGF), Hutti Gold Fields (HGF) and Gadag Gold Fields (GGF). Karnataka is the prime state for gold production since all of these gold deposits are located within. Apart from these world class gold deposits, several other gold prospects in India were identified and exploration activities are under progress. The present study aims to characterize the mineral assemblage and paragenetic phases of gold bearing Precambrian rocks around Hosur village in Gadag Schist Belt through detailed examination by Ore Microscopy. Gadag Schist Belt (GSB) is known by its significance of gold deposits for centuries. Gold mineralization in GSB is associated with tholeiitic meta-andesite, quartz porphyries and argillite greywacke assemblage. The Gadag Gold Field (GGF) constitutes one of the most important auriferous zones of the Archaean Greenstone terrains in Southern India. All known mineralization is in the form of structurally controlled vein systems. The occurrence of the gold is intimately associated with arsenopyrite. Representative samples were studied under polarizing reflected-light microscope to identify and to characterize the mineral phases of gold occurrences and its textural relationships. It has been observed that there are five phases of mineralization only in the third phase gold has formed along with arsenopyrite. Surface morphology of gold and sulphide mineralization was examined under SEM; whereas the elemental analysis of selected sample was carried out using EDS.The present work reveals the clear perception of gold occurrence and mineral phases paragenesis using ore microscopic approach.
Petrological and Geochemical Characteristics of Al-rich Pelitic Granulites/Paragneiss from Thana, District-Bhilwara Rajasthan: Implication for Its Origin
New Five Southern Tethyan Agglutinated Foraminiferal Species
An Overview of Stratospheric Ozone and Climate Effects
An Account of Field and Petrographic Characteristics of Granitic Rocks of Che...ijtsrd
Field geological and petrographic characteristics of granitic rocks of Cherlapally area, Nalgonda district, Telangana, within the eastern Dharwar craton are described in this paper. Field traverses revealed four types of granitic rocks in the study are viz., quartz diorite, granodiorite, monzogranite and syenogranite. The variations in the texture and mineralogical composition of these plutons are so distinct that the term migmatite' has to be applied, wherein mutual field relations always remain enigmatic. The complex nature of the batholiths is also evident from the structural fabrics observed in the present investigation. N. Ningam | P. R. C. Phani "An Account of Field and Petrographic Characteristics of Granitic Rocks of Cherlapally Area, Nalgonda District, Telangana" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25202.pdfPaper URL: https://www.ijtsrd.com/other-scientific-research-area/geology/25202/an-account-of-field-and-petrographic-characteristics-of-granitic-rocks-of-cherlapally-area-nalgonda-district-telangana/n-ningam
Preliminary Studies of the Litho-Structural Evolution of Areas Around Obudu N...IJRESJOURNAL
ABSTRACT: Rocks underlying the northeastern sector of Obudu area forms part of the Bamenda massif which is a westward extension of the Precambrian terrains of Cameroon into southeastern Nigeria. These rocks are frequently found in the basement complex of Nigeria and include the migmatitic gneiss as the early metamorphic tectonites constituting over 60% of the outcropping rocks in the study area. The basement rock of the study area comprised of the migmatite gneiss and biotite-hornblende garnetiferous gneiss as well as the porphyroblastic gneiss and granite gneiss which formed the basement intruded by the Older granites (Pan-African granitoids). The Older granites in this area include charnockite, porphyritic granite, medium grained granite, diorite and pegmatite/aplite with relatively undeformed veins of dolerite and quartz. The presence of garnet nodules in the biotite-hornblende gneiss indicates high grade tectono-thermal metamorphism of a possible sedimentary protholith. The shearing observed in some rock outcrops are indication that there have been a series of structural deformation alongside magmatism and metamorphism in the area.
Petrological and Geochemical Studies on Granitoids in BibinagarBhongir Area, ...IJERA Editor
The Granitoids of the Bibinagar- Bhongir area in the Nalgonda district are purely high potassic calc alkaline and
meta aluminous and A-type belongs to Peninsular Gneissic Complex of the Eastern Dharwar Craton. The
petrographic study of granitoids indicates that of pure magmatic origin in the form of different magmatic
textures viz. perthitic, porphyritic and poiklitic textures. Geochemically the granitoids are rich in K2O & Na2O
suggesting source from calc-alkaline magma. The Granitoids are falling mostly in the volcanic arc field on Yb
vs Ta discrimination plot. The REE pattern shows strong Eu negative anomaly, suggesting early separation of
plagioclase and the enhanced level of LILE relative to HFSE in Bibinagar-Bhongir granitoids points to the
subduction zone enrichment and/or crustal contamination of the source region.
Measurement of Pan-African Strain in Zaria Precambrian Granite Batholith, Nor...iosrjce
The Zaria granite batholith in northern Nigeria is an example of syn-tectonic batholith emplaced
about 600 ± 150 Ma, ago during the Pan - African orogeny. Its strain history and strain marker behavior have
been studied in order to further elucidate the tectonics of the Pan- African orogeny. Field observations,
measurements and different methods of strain estimation were applied on 623 data to determine the strain
intensity, direction of maximum elongation (σ3) and compression direction (σ1). The different methods produced
strain values between 2.66 and 2.07, maximum elongation took place in the N - S direction while the σ1
(maximum compression) trajectory was oriented E – W, making the direction the least favourable for strain
marker (phenocryst and xenolith) growth. Strain partitioning revealed that the N - S direction experienced the
highest strain while the NE - SW orientation showed a lower strain value than the NW - SE direction regardless
of the number of markers preferring the directions. Xenoliths, faults and joints lend credence to the measured
strain results. It would seem that the E - W compression during the Pan - African orogeny was widespread and
fairly constant throughout most of the period tracked by the granites.
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
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Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Venturesgreendigital
Willie Nelson is a name that resonates within the world of music and entertainment. Known for his unique voice, and masterful guitar skills. and an extraordinary career spanning several decades. Nelson has become a legend in the country music scene. But, his influence extends far beyond the realm of music. with ventures in acting, writing, activism, and business. This comprehensive article delves into Willie Nelson net worth. exploring the various facets of his career that have contributed to his large fortune.
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Introduction
Willie Nelson net worth is a testament to his enduring influence and success in many fields. Born on April 29, 1933, in Abbott, Texas. Nelson's journey from a humble beginning to becoming one of the most iconic figures in American music is nothing short of inspirational. His net worth, which estimated to be around $25 million as of 2024. reflects a career that is as diverse as it is prolific.
Early Life and Musical Beginnings
Humble Origins
Willie Hugh Nelson was born during the Great Depression. a time of significant economic hardship in the United States. Raised by his grandparents. Nelson found solace and inspiration in music from an early age. His grandmother taught him to play the guitar. setting the stage for what would become an illustrious career.
First Steps in Music
Nelson's initial foray into the music industry was fraught with challenges. He moved to Nashville, Tennessee, to pursue his dreams, but success did not come . Working as a songwriter, Nelson penned hits for other artists. which helped him gain a foothold in the competitive music scene. His songwriting skills contributed to his early earnings. laying the foundation for his net worth.
Rise to Stardom
Breakthrough Albums
The 1970s marked a turning point in Willie Nelson's career. His albums "Shotgun Willie" (1973), "Red Headed Stranger" (1975). and "Stardust" (1978) received critical acclaim and commercial success. These albums not only solidified his position in the country music genre. but also introduced his music to a broader audience. The success of these albums played a crucial role in boosting Willie Nelson net worth.
Iconic Songs
Willie Nelson net worth is also attributed to his extensive catalog of hit songs. Tracks like "Blue Eyes Crying in the Rain," "On the Road Again," and "Always on My Mind" have become timeless classics. These songs have not only earned Nelson large royalties but have also ensured his continued relevance in the music industry.
Acting and Film Career
Hollywood Ventures
In addition to his music career, Willie Nelson has also made a mark in Hollywood. His distinctive personality and on-screen presence have landed him roles in several films and television shows. Notable appearances include roles in "The Electric Horseman" (1979), "Honeysuckle Rose" (1980), and "Barbarosa" (1982). These acting gigs have added a significant amount to Willie Nelson net worth.
Television Appearances
Nelson's char
Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Ventures
14. rajiullah khan, mohd shaif
1. 89
Journal of Global Resources Volume 6 (01) August 2019-January 2020 Page 89-95
UGC–CARE Listed Journal in Group D ISSN: 2395-3160 (Print), 2455-2445 (Online)
14
PETROGRAPHIC CHARACTERISTICS OF HOST AND ASSOCIATED ROCKS IN THE PB-
ZN DEPOSIT OF RAMPURA-AGUCHA AREA, BHILWARA BELT (RAJASTHAN) INDIA
Rajiullah Khan1
, Mohd Shaif2
, F.N. Siddiquie3
and Masood Ahmed4
1
Research Scholar, 2
Assistant Professor, 3
Professor, 4
Independent Scholar
Department of Geology, Aligarh Muslim University, Aligarh (UP), India
Email: rajiullahkhan17@gmail.com, msaif125@gmail.com, fnaseem2000@yahoo.com
Abstract: The present study is to confine the Rampura-Agucha area, Bhilwara district,
Rajasthan, which occurs in Bhilwara Super group at the contact with Banded Gneissic
Complex. The Bhilwara belt is a thick pile of metasedimentary rocks in the eastern part of
Aravalli-Delhi belt that consists dominant litho-units viz: graphite–sillimanite–garnet schist,
garnet–biotite–sillimanite gneisses with garnet-bearing leucosomes as well as amphibolites,
pegmatites and some scattered calc-silicates while the Pb-Zn ore deposit mainly occurs within
graphite-biotite-sillimanite schist. The mineralogical assemblages of host rocks explain that
they are formed under the high grade of metamorphism, primarily upper amphibolite to
granulite facies condition. These Pb-Zn bearing ore are intimately associated with schist. The
inclusions of quartz are common in garnets, while ore minerals also contain the inclusion of
quartz and feldspar. The highly fractured grains of garnet, hornblende and pyroxene due to
deformation, and pressure are observed in these host rocks while the contact between the
quartz grains is of suture type in the calc-silicate rock.
Key words: Pb-Zn, Bhilwara Super group, Petrography, Rocks and Minerals
Introduction
The Pb-Zn deposits of the Rampura-Agucha area occur within Mesoproterozoic meta-
sedimentary rocks belonging to the Bhilwara supracrustal belt of Aravalli-Delhi orogen in the
Bhilwara district of Rajasthan state (Deb & Sarkar, 1990), which is located about 220 km to the
SW of the state capital, Jaipur. The area is very much renowned due to its largest Pb-Zn
deposits, where the ore body is extending over a strike length of about 1.55 km with on average
width of 60 m while at places the maximum width goes up to 100 m. The rough estimation of
Pb-Zn ore reserve is around 63.65 million tonnes with an average content of 13.38 percent Zn,
1.9 percent Pb and 9.58 percent Fe (Gandhi et al., 1984). The Pb-Zn bearing rocks
encountered in the present study area are metamorphosed to mainly upper amphibolite to
granulite facies, estimated by Ranawat et al. (1988), Deb & Sarkar (1990). Several pioneer
workers Gandhi et al. (1984), Ranawat et al. (1988), Ranawat & Sharma (1990) and Sharma &
Singh (1990) are continuously involved in the study of these ores and its associated rocks.
Recently, Chattopadhyay (2017), mentioned that a large scale of remobilization of ore during
metamorphism is evidenced mainly in the cleavage and fracture of the associated silicates.
Finally, the present authors did the petrographic studies of the rocks to understand the petro-
mineralogical associations in the study area. However, such type of study always provides
relevant information over mineralogy, textural properties, P-T conditions and paragenetic
history of rocks, which formed the base for depth studies of the area.
Geology of the Study Area
The regional geology of south-eastern Rajasthan is shown by the Banded Gneissic Complex
(BGC), Aravalli Supergroup and Delhi Super group (Heron, 1953). The pre-Aravalli group was
renamed as Bhilwara Super group, representing the Bhilwara geological cycle of Archean age,
however, there is a controversy regarding the separate status of Bhilwara Super group.
According to Raja Rao (1976), Bhilwara Super group is older than the Aravalli but Roy et al.
(1981), Naha & Halyburton (1974 & 1977) and Naha & Roy (1983), stress that there is a
striking similarity in the structures of the Bhilwara Super group and the Aravalli rocks. The Pb-
Zn deposits of Rampura-Agucha area are located close to the Delwara lineament (Gupta et al.,
1980) between the Mangalwar complex and the Sandmata complex that form a part of Bhilwara
Super group/Banded Gneissic Complex. Geologically, the study area comprises an
2. 90
assemblage of pelitic rocks that constitutes the graphite-biotite-sillimanite schist and garnet-
biotite-sillimanite gneiss. These pelitic rocks constitute the most dominant lithologic unit
exposed in the study area along with garnet-bearing leucosomes, calc-silicate gneisses,
amphibolites and pegmatites (Gandhi et al., 1984; Mishra & Bernhardt, 2009). The host rocks
in the study area show NE-SW strike with a steep dip in hanging wall side (750-800SE) and
moderate dip in the footwall side (600-650SE). The general strike of the ore zone is parallel to
the enclosing rocks (NE-SW) while the dip of the ore zone is varying along the strike. The rocks
of the Rampura-Agucha area are metamorphosed sedimentary enclaves with an unknown
stratigraphic contact with the Archean basement (Sinha-Roy, 1989). According to Deb and
Sehgal (1997), the sequence of litho-units is seen from eastern hanging wall to western footwall
of Rampura-Agucha Pb-Zn ore deposits are as follows:
Garnet-biotite-sillimanite gneiss (GBSG) with intermittent bands of amphibolites and
calc-silicate rocks, intruded by aplite and pegmatite;
Graphite-mica-sillimanite schist (ore body);
GBSG with lenses of amphibolites, quartzo-feldspathic bands and calc-silicate rocks
intruded by pegmatite/aplites veins;
Granite-gneiss;
Severely mylonitized GBSG;
Banded and augen gneiss.
The rocks in the area have been subjected to polyphase deformation and metamorphosed up
to high grade with zones of mylonite (HZL, 1992). According to Ray (1982), the area around the
Rampura-Agucha ore deposits has suffered three-phase of deformation namely-
i. An initial isoclinal folding with a variable plunge and axial plane that produced WNW-
ESE trending folds;
ii. Subsequent isoclinal folding which folded the S1 axial plane about a NE-SW axis;
iii. A weak, local phase of upright, steeply plunging fold.
Figure 01: Simplified geological map of Rampura-Agucha Ore body and Surrounding
Rocks (Simplified after Holler & Gandhi, 1995)
Sampling and Analytical Methods
The author visited the Rampura-Agucha mines and its surrounding area, Bhilwara District,
Rajasthan. Due to the scanty and non- availability of rock exposures in the study area, samples
of different rocks types were collected from the Rampura-Agucha mine, small stone queries
and available rock exposures along the Mansi River. About 40 samples of all rock types were
collected from a different location, from each collected samples, few thin sections were
prepared by following Grundmann & Scholz (2015). Thin sections studied in transmitted light
3. 91
under the petrological microscope and powdered the five selected samples to 200 mesh size in
grinding mill (for XRD analysis) was carried out in the Department of Geology, AMU., Aligarh.
The powdered rock samples were analyzed in the Department of Mechanical Engineering,
AMU, Aligarh. The XRD pattern was recorded from 50 to 900 with a step size of 0.050 /sec,
using nickel filtered Cu Kα radiations. The data was interpreted and plotted by X'pert High
Score Plus and Origin Pro 8.5, respectively.
PETROGRAPHY
Graphite-biotite-sillimanite Schist
It is the main rock type that hosts the mineralization of the ore. In the field, it shows a very
sharp contact with other surrounding rocks and within these rock units, there are few bands of
calc-silicates which are barren of ore mineralization except for sporadic specks of pyrite
(Gandhi et al., 1984). Megascopically, it is coarse-grained and shows well-developed
schistosity and also contains pink color garnet porphyroblasts. The lead and zinc ore are
associated with graphite-biotite-sillimanite schist mostly in laminated form. Under the
microscope, it chiefly consists of quartz, biotite and sillimanite with a considerable amount of
graphite as well as potash feldspar, garnet and opaque minerals. The accessory minerals are
apatite and tourmaline. The graphite mineral occurs as a subhedral fragments along with
feldspar, biotite, and quartz (Fig.3.e). On the other hand, sillimanite is associated with biotite
and garnet along well developed foliation. Deformation in the twin planes of plagioclase
commonly observed in the thin section (Fig.3.f). Quartz and biotite are common inclusion in the
garnet formed the poikiloblastic texture. Quartz grains are xenoblastic and show undulose
extinction. Biotite flakes uniformly cleaved with preferred orientation results in the formation of
the schistosity. Generally, garnet grains are fractured and occur same time with biotite and
sillimanite. The 2θ position of different minerals in the graphite-biotite-sillimanite schist of the
study area has given in figure 2.A.
Garnet-biotite-sillimanite Gneiss
It is the prevailing lithology within and around the mine. It represents a metasedimentary
sequence of shale and slate. Megascopically, these rocks are medium to coarse grained,
showing gneissose structure. They are foliated and contain the leucocratic bands of quartz and
feldspar with insignificant amount of tourmaline alternating with melanocratic layers rich in
biotite and garnet. It is very heterogeneous and shows a well-developed augen structure in
which fine grained minerals wrapped around the garnet porphyroblasts. Garnet and feldspar
porphyroblasts are ranged from few mm to 100 mm in size and set in a gneissic to schistose
groundmass (Gandhi et al., 1984; Ranawat & Sharma, 1990; Sharma & Singh, 1990). Under
the thin section studies, gneiss samples are medium to coarse grained and consist of quartz,
microcline, plagioclase, sillimanite, garnet, and accessory minerals, including zircon, apatite,
tourmaline and magnetite. Garnet grains are highly shattered and show the inclusions of quartz
(Fig.3.h). These inclusions are limited to the central part of the garnet porphyroblasts while the
outer side is generally lacking any such inclusions. The dominant garnet composition is
almandine (Holler, Touret, & Stumpfl, 1996). Garnet and feldspar occur as a porphyroblast
while sillimanite grains occur as needles and form clusters. Biotite occurs as a tabular
aggregate with traces of sericite. The 2θ position of biotite, graphite, quartz and sillimanite in
the garnet-biotite-sillimanite gneiss has given in figure 2.B.
Calc-silicate Rock
The samples of calc-silicate rocks are collected from the Rampura-Agucha open cast mine and
Mansi River. It is the minor component of the lithological assemblages and occurs as irregular
bands within the gneiss. It is hard and compact, consequently resistant to weathering, forming
prominent boulder outcrops. In hand specimens, these rocks are fine to medium grained types
with frequent garnet porphyroblasts of various sizes.
4. 92
Figure 02. (A) 2θ Position of biotite, galena, microcline, quartz and sphalerite in Schist; (B) 2θ
Position of biotite, graphite, quartz and sillimanite in Gneiss; (C) 2θ Position of anorthite,
enstatite, labradorite and quartz in Calc- silicate; (D) 2θ Position of actinolite, andesine,
hornblende, labradorite and quartz in Amphibolite; (E) 2θ Position of biotite, plagioclase and
quartz in pegmatite, Bhilwara belt, Rajasthan.
Figure 03: Representative Transmitted Light Microphotograph of Different Rock Units
(B)(A)
(C) (D)
(E)
5. 93
(a) Showing coarse grained quartz (Qtz), biotite (Bt) and garnet (Grt) in Pegmatite, near Bhopalpura village, (b)
Showing highly recrystallized quartz grains (suture contact) in calc-silicate at Rampura-Agucha open cast mines,
Bhilwara belt, (c) Showing the large hornblende (Hbl) and clinopyroxene (Cpx) crystal breaking down to an
aggregate of small crystals (mortar texture) in amphibolite at stone quarry near Amartiya road, (d) Amphibolite,
showing hornblende with plagioclase (lamellar twinning), microcline (Mic), quartz and biotite, stone quarry near
Amartiya road, Bhilwara belt, Rajathan.
Fine laminations of a millimeter-scale and compositional variations are also seen in this
rock. Microscopically, various samples of calc-silicate rock have been taken for petrographic
studies which show the presence of diopside, plagioclase and garnet with minor quartz, k-
feldspar and rare hornblende as principal constituents, and scapolite, zoisite, titanite and
sphene occur as accessory minerals. Plagioclase occurs as tabular and sub-idioblastic grains
while microcline grains are xenoblastic to sub-idioblastic grains. Quartz grains are highly
crystallized, showing the suture contact (Fig.3.b). The 2θ positions of different minerals in calc-
silicate rock shown in figure 2.C.
Amphibolite
Amphibolite samples are collected from stone quarry near Amartiya road and Rampura-Agucha
mines. Amphibolites in the study area show an inter-fingering relationship with the calc-silicate
rocks and occur as bands of different width in the garnet-biotite-sillimanite gneiss. Two types of
amphibolite have seen in the study area (i) schistose amphibolite and (ii) granoblastic
amphibolite. They are generally medium to coarse grained in nature. Out of both varieties,
schistose amphibolites occur as enclaves, while granoblastic amphibolites show intrusive
nature with country rocks. Megascopically, it appears dark green to black color, and are
generally medium to coarse grained rocks.
Figure 3. (e) Fine grained garnet-biotite-sillimanite schist showing orientation of quartz and micaceous
minerals, Rampura-Agucha open cast mines, (f) Garnet-biotite-sillimanite schist, showing the plagioclase
with deformation twins, Rampura-Agucha open cast mines, (g) GBSG, showing garnet, microcline (cross
hatched twinning) and angular shaped quartz at Mansi river, (h) GBSG, showing inclusions of quartz and
biotite in garnet, Mansi river, Bhilwara belt, Rajasthan.
6. 94
It shows a granoblastic to loosely foliated texture. Garnet grains in the amphibolite of
the study area occur as a porphyroblast. Microscopically, it is composed of essentially
hornblende, plagioclase and garnet along with diopside, biotite and quartz. Pyroxene and
hornblende crystals are breaking down to an aggregate of small crystals forming the mortar
texture (3.c). Pyroxene grains are riddled with inclusions of quartz and hornblende, while the
hornblende grains are relatively free from the inclusions. Hornblende is showing perfect two set
cleavages while both plagioclase and microcline are showing their characteristic properties i.e.,
lamellar and cross-hatched twinning respectively (Fig.3.d). Triple junctions are clearly seen in
the hornblende grain (Fig.3.c), indicating the dynamic recrystallization. According to Roy
(2000), amphibolite of the study area to be para-amphibolite formed by high-grade
metamorphic facies of impure dolomitic limestone. X-ray diffraction pattern of different minerals
in amphibolite has given in fig.2.D.
Pegmatite
In the study area, the pegmatite samples are collected from Rampura-Agucha mines.
Pegmatites are common in the study area with individual pegmatite components may be up to
40 meters in thickness locally (Gandhi et al., 1984). Thin veins of pegmatite are seen as
intrusive in the garnet-biotite-sillimanite gneiss, amphibolites and calc-silicate rocks. In hand
specimens study, It is coarse grained rocks. Garnet grains of different sizes are also present in
the pegmatite. Microscopically, pegmatites consist of mainly coarse grained quartz, plagioclase
and biotite with a minor percentage of garnet (Fig. 3.a). Quartz occurs as a xenoblastic grain,
while biotite found as elongated grains. Quartz and feldspar form a graphic intergrowth texture.
The 2θ position of biotite, plagioclase and quartz in pegmatite is shown in figure 2.E.
Mineral Assemblages
Based on petrographic and X-ray diffraction studies of various rock types in the study area, the
followings mineralogical assemblages are identified and listed in table1.
Table 01: Mineral Assemblage in the Host and Associated Rocks of the Study Area
# Rock types Mineral assemblages
1 Graphite-biotite-sillimanite-schist Quartz, biotite, sillimanite, graphite, microcline, garnet,
apatite, tourmaline and opaque minerals
2 Garnet-biotite-sillimanite gneiss Quartz, microcline, plagioclase, sillimanite, garnet, zircon,
apatite, tourmaline and magnetite
3 Calc-silicate rock Diopside, microcline, anorthite, labradorite, quartz,
enstatite, sillimanite, garnet, scapolite, zoisite, titanite and
sphene
4 Amphibolite Hornblende, actinolite, plagioclase (andesine, labradorite),
garnet, diopside, biotite and quartz
5 Pegmatite Quartz, plagioclase, biotite, tourmaline and garnet
Conclusion
The Pb-Zn deposits of the Rampura-Agucha area occur within meso-proterozoic meta-
sedimentary rocks belonging to the Bhilwara supracrustal belt and consist of pelitic rocks that
constitute the graphite-biotite-sillimanite schist, garnet-biotite-sillimanite gneisses along with
calc-silicate, amphibolite and pegmatite. On the basis of petrographical investigations, it
appears that regional metamorphism has played an important role in metamorphism of pelitic
rocks up to upper amphibolite to granulite facies, which are the prominent host rocks of
Rampura-Agucha Pb-Zn deposit. The textures observed in the rocks under investigation reveal
the pre-tectonic crystallization of mineral grains as well as the multiphase of deformation. Thin
section studies and X-ray diffraction patterns of different rock types in the area suggest the Pb-
Zn ores are found in schist and deposited along the mineral grain boundaries and generally,
found as dark color patches in thin sections.
Acknowledgments
The author is grateful to Prof. Syed Ahmed Ali, Chairman, Department of Geology, AMU,
Aligarh, and Dr. S. A. Rashid, Associate Professor, Department of Geology, AMU, for the
laboratory work. Mr. Bingi Murli, AGM, Rampura-Agucha mine, his cooperation in field
assistance is appreciated. The author is grateful to CSIR-JRF for financial support.
7. 95
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