scholarly journals Provenance of the Sawa Formation Sandstones, Vindhyan Super Group, Southeast Rajasthan, India

2021 ◽  
Vol 38 (1) ◽  
pp. 93-102
Author(s):  
JYOTI MATHUR

Integrated petrographical and geochemical analysis of Sawa Formation sandstones was analyzed to reconstruct their source area weathering, paleoclimate, tectonic setting and provenance conditions. Petrographically, quartz is dominant detrital mineral followed by feldspar, mica, rock fragments and heavy minerals. Sawa Formation sandstones have been classified as quartzarenite with subordinate sub-arkose and sub-litharenite type. Major oxide element abundances revealed the sandstones have high SiO2 concentration, high K2O/ Na2O ratio, which is consistent with the petrographic data. These sandstones were derived mainly from stable cratonic with minor collision suture and fold thrust belt source and deposited in rifted continental margin basin setting, reflecting high maturity of sediments and high stability of the source area. The CIA, CIW and PIA values of these sandstones indicate high intensity of weathering condition in the source area under warm and humid climate.

2014 ◽  
Vol 6 (2) ◽  
pp. 47 ◽  
Author(s):  
Ikhane P. R. ◽  
Akintola A. I. ◽  
Bankole S. I. ◽  
Oyinboade Y. T.

The petrography, as well as the major, trace and rare earth element compositions of ten (10) sandstone samples of Maastrichtian Afowo Formation exposed near Igbile, Southwestern Nigeria, have been investigated to determine their provenance, source area weathering conditions, paleoclimate and tectonic setting using petrographic analysis and Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). Results of the petrographic analysis revealed that quartz is the most dominant detrital mineral with (86%) followed by weathered plagioclase feldspar (5.10%) and rock fragments (10.9%). The quartz grain is sub-angular to sub-rounded in shape and the sandstones were classified as quartz arenites, sublitharenites and subarkoses based on framework composition of quartz, feldspar and rock fragment plots. This suggests a recycled orogen source for the sandstones and deposition in a humid climate, evidenced by the weathered feldspars. Eleven (11) major, seventeen (17) trace and fourteen (14) rare earth elements were obtained from the geochemical analysis. The major elements values range in concentration from 0.01%–81.39% with SiO2 being the dominant oxide followed by Al2O3 and Fe2O3 constituting over 95% of the major oxides; K2O, TiO2, Na2O, CaO, MgO and P2O5 made up the remaining 5%. The average ratio of SiO2/Al2O3 valued 4.31 for the sandstone is appreciably high indicating that it has been heavily weathered. The trace elements range in concentration from 0.2 ppm–1651.2 ppm with Zr being the most dominant element an indication of orogenic recycling. The rare earth elements range in concentration from 0.01 ppm–163.7 ppm with Ce having the highest concentration, depicting that the sandstones were deposited in an oxidizing environment. Also, the trace element relationship illustrated from the spider plot shows chemical coherence and uniformity of the sandstones. The chondrite normalized rare earth elements (REE) plot shows enrichment in the Light REE over the heavy REE for the sediment with strong negative Eu anomaly values between (0.57–0.69) suggesting a felsic provenance derived from upper continental crust for the sandstones.


2015 ◽  
Vol 154 (1) ◽  
pp. 1-23 ◽  
Author(s):  
HOSSAM A. TAWFIK ◽  
IBRAHIM M. GHANDOUR ◽  
WATARU MAEJIMA ◽  
JOHN S. ARMSTRONG-ALTRIN ◽  
ABDEL-MONEM T. ABDEL-HAMEED

AbstractCombined petrographic and geochemical methods are utilized to investigate the provenance, tectonic setting, palaeo-weathering and climatic conditions of the Cambrian Araba clastic sediments of NE Egypt. The ~ 60 m thick Araba Formation consists predominantly of sandstone and mudstone interbedded with conglomerate. Petrographically the Araba sandstones are mostly sub-mature and classified as subarkoses with an average framework composition of Q80F14L6. The framework components are dominated by monocrystalline quartz with subordinate K-feldspar, together with volcanic and granitic rock fragments. XRD analysis demonstrated that clay minerals comprise mixed-layer illite/smectite (I/S), illite and smectite, with minor kaolinite. Diagenetic features of the sandstone include mechanical infiltration of clay, mechanical and chemical compaction, cementation, dissolution and replacement of feldspars by carbonate cements and clays. The modal composition and geochemical parameters (e.g. Cr/V, Y/Ni, Th/Co and Cr/Th ratios) of the sandstones and mudstones indicate that they were derived from felsic source rocks, probably from the crystalline basement of the northern fringe of the Arabian–Nubian Shield. The study reveals a collisional tectonic setting for the sediments of the Araba Formation. Palaeo-weathering indices such as the chemical index of alteration (CIA), chemical index of weathering (CIW) and plagioclase index of alteration (PIA) of the clastic sediments suggest that the source area was moderately chemically weathered. On the northern margin of Gondwana, early Palaeozoic weathering occurred under fluctuating climatic conditions.


2021 ◽  
Vol 13 (1) ◽  
pp. 1187-1225
Author(s):  
Temitope Love Baiyegunhi ◽  
Kuiwu Liu ◽  
Oswald Gwavava ◽  
Christopher Baiyegunhi ◽  
Maropene Rapholo

Abstract An inorganic geochemical investigation of mudrocks and sandstone from the southern Bredasdorp Basin, off the south coast of South Africa was carried out to unravel the provenance, paleoweathering, and tectonic setting of the basin. Seventy-seven representative samples from exploration wells E-AH1, E-AJ1, E-BA1, E-BB1, and E-D3 underwent geochemical analysis involving major and trace elements. The major oxide compositions show that the sandstones could be classified as sub-arkose and sub-lithic arenite. The provenance discrimination diagrams based on major oxide geochemistry revealed that the sandstones are mainly of quartzose sedimentary provenance, while the mudrocks are of quartzose sedimentary and intermediate igneous provenances. The discrimination diagrams indicate that the Bredasdorp sediments were mostly derived from a cratonic interior or recycled orogen. The bivariate plots of TiO2 versus Ni, TiO2 against Zr, and La/Th versus Hf as well as the ternary diagrams of V–Ni–Th∗10 suggest that the mudrocks and sandstones were derived from felsic igneous rocks. The tectonic setting discrimination diagrams support passive-active continental margin setting of the provenance. Also, the closely similar compositions of the analysed samples and recent sedimentary rocks of the East African Rift System perhaps suggest a rifted basin tectonic setting for the Bredasdorp Basin. Chemical index of alteration (CIA) indices observed in the sandstones suggest that their source area underwent low to moderate degree of chemical weathering. However, the mudrocks have high CIA indices suggesting that the source area underwent more intense chemical weathering, possibly due to climatic and/or tectonic variations.


Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 813
Author(s):  
Md Aminur Rahman ◽  
Sudeb Chandra Das ◽  
Mark I. Pownceby ◽  
James Tardio ◽  
Md Sha Alam ◽  
...  

Sediments from stable sand bars along a 40 km section of the Brahmaputra River in northern Bangladesh were analyzed for their major, trace and rare earth element contents to determine their provenance, compositional maturity, source area weathering and tectonic setting. Geochemically, the sediments were classified as litharenites and the Index of Compositional Variability (ICV) varied between 1.4 and 2.0, indicating low compositional and mineralogical maturity. A high mean SiO2 concentration (72.9 wt.%) and low Al2O3 (11.1 wt.%) were consistent with a low abundance of shale and clay components. The depletion of the oxide components Na2O, CaO and K2O relative to average upper crustal compositions (UCC) reflected loss of feldspar during chemical weathering in the source region. Average TiO2 values for most samples were higher than average crustal levels, consistent with the northern section of the Brahmaputra River being a potential resource for valuable Fe-Ti oxide heavy minerals. Major and trace element ratios indicated the sediments represented erosional products from typical felsic upper continental crustal materials with contamination (30%–40%) from more intermediate/mafic compositions. The rare earth element patterns showed negative Eu anomalies (0.57–0.71), indicating they were derived mainly from fractionated felsic rocks. Resemblance of the sediment compositions to mean compositions from Higher Himalaya crystalline rocks pointed to these being potential source rocks but with components from a mafic source also present. Major element chemistries and low to intermediate weathering indices for all sediments indicated a lack of substantial chemical weathering. Evidence from tectonic discrimination diagrams suggested the Brahmaputra River sediments were derived from rock types that formed in a transitional tectonic setting ranging from an ancient passive margin to an active continental margin. Deposition occurred under cool to semi-arid climatic conditions in an oxic environment.


1962 ◽  
Vol 65 (6) ◽  
pp. 107-137 ◽  
Author(s):  
Gilbert Kelling

SynopsisThe petrology of a group of geosynclinal rudites and arenites of Upper Ordovician age from the Rhinns of Galloway, south-west Scotland, is described. The rudites are confined to the oldest formation, the Corsewall Group, and consist of pebbly microbreccias and “boulder-beds” interbedded with coarse greywackes and platy siltstones. The composition of the microbreccias and boulder-beds varies little with stratigraphic level.The arenites comprise lithic, coarse-grained greywackes with occasional quartzose or feldspathic varieties. They carry, in aggregate, a wide range of igneous, metamorphic and sedimentary rock-fragments, quartz of variable source, a variety of feldspars, ferromagnesian minerals, micas, chlorites and a common to conspicuous argillaceous matrix. The greywackes are well defined stratigraphically as regards both overall composition and the character of the large mineral grains and rock-fragments (“granules”). Moreover composition appears to be related to grain-size in a consistent manner. The size-distribution, sorting and skewness of the greywackes based on thin section measurements show little stratigraphic variation.The aggregate suite of heavy minerals is meagre and only minor differences exist in the individual formation-suites.The character of the rock-fragments and mineral grains suggests that the earlier formations were derived from a nearby source-area in which plutonic and hypabyssal acid and basic igneous rocks were extensively exposed, together with spilitic lavas and glaucophane schists. The petrology of the upper formations reveals that a metamorphic terrain of Southern Highlands aspect became an important additional source of material. However, the highest beds were derived from a region dominated by andesitic and spilitic tuffs and lavas.The principal directional sedimentary structures are described briefly and it is suggested that the lower part of the Corsewall Group, derived mainly from the north and north-east, was deposited in a sheltered pro-delta environment, but that the boulder-beds and associated rocks were formed within a more boisterous region. The Kirkcolm Group is a turbidite-sequence deposited in a marine trough of moderate depth by currents which at first flowed dominantly in opposing directions, towards either north-east or south-west. However, transport from the north-east became progressively established. The Portpatrick Group is another turbidite-sequence but this formation was deposited by currents flowing from the west or south-west.


2021 ◽  
Vol 14 (4) ◽  
Author(s):  
Armel Zacharie Ekoa Bessa ◽  
Paul-Désiré Ndjigui ◽  
Gentry Calistus Fuh ◽  
John S. Armstrong-Altrin ◽  
Thierry Bineli Betsi

AbstractThis study investigates the provenance, paleoweathering, and paleoclimate of the Ossa lake sediments, based on the mineralogy and geochemistry data. Ossa lake sediments are characterized by silt and clay with high content of total organic carbon (TOC). Clay minerals are identified as kaolinite and illite types. Other dominant minerals identified are quartz, zircon, rutile, goethite, gibbsite, feldspar, and accessory vivianite. The major, trace, and rare earth element concentrations indicate that the sediments were derived from felsic rocks, such as gneisses and granitoids. The tectonic discrimination diagrams revealed an active margin setting. Weathering indices such as the chemical index of alteration (CIA), the plagioclase index of alteration (PIA), and chemical index of weathering (CIW) suggest intense chemical weathering in the source area. K2O/Na2O ratio and index of compositional variation (ICV) are consistent with high maturity of the sediments. The mineral assemblages and trace elemental ratios and climatic index “C” of the Ossa Lake sediments suggest a warm to semi-humid climate and deposition in an oxic shallow environment.


2017 ◽  
Vol 46 (1) ◽  
pp. 3-25
Author(s):  
Athanas Chatalov

Quartz-rich sandstones and ironstone crusts occur in the lowermost part of the Upper Triassic Moesian Group exposed in the western Balkanides. On the basis of performed field studies, micropetrography, X-ray diffraction, and major-element chemistry, these deposits are defined as first-cycle quartz arenites and laterites, respectively. The former were deposited in an alluvial environment, while the latter developed in gravel-dominated fluvial sediments. The main control on their formation was warm to hot humid climate conditions combined with low relief, quiescent tectonic setting, mixed source area, and slow sedimentation rate. The decreasing compositional maturity of the sandstones forming the Glavatsi Member (quartz arenites→feldsarenites→litharenites), the disappearance of the lateritic crusts upwards in the continental succession, and the presence of thick overlying fluvial and playa deposits in the Komshtitsa Formation (or Chelyustnitsa Formation) reflect gradual transition from humid to subhumid climate, and then to persistent semi-arid climate regime. This irreversible trend correlates with other Upper Triassic strata deposited in the Western Tethys realm and adjacent areas. The coeval formation of quartz arenites and laterites must have been related to the most distinctive climate change during the Triassic, i.e., the global Carnian Humid Episode. The new results and interpretations appear to be the first geological record for the effect of pronounced mid-Carnian humidity reported from Eastern Europe. They also present indirect sedimentological evidence for the stratigraphical range of the Moesian Group in NW Bulgaria.


2020 ◽  
Vol 8 (2) ◽  
pp. 279
Author(s):  
G. U. Ozulu ◽  
A. U. Okoro ◽  
V. O. Ndubueze

The petrography and geochemistry of major and trace elements distribution pattern for the Lokoja Sandstones, Southern Bida Basin, Nigeria; were used to interpret their provenance, weathering conditions and paleotectonic setting. A total of seven (7) representative sandstone samples were selected for petrographic, heavy minerals and inorganic geochemical analyses; that is X- ray diffraction (XRD), X-ray fluorescence (XRF) and Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Results of the petrographic analysis showed 52.14 % quartz, 39.29 % feldspar, 2.00 % rock fragments, 5.14 % matrix and cement fraction as well as 1.43 % unfilled voids. Results of major elements and oxides suggests intermediate to felsic source rocks while the dominance of Na-rich feldspar to the k-feldspar and high value of Fe2O3+MgO shows contribution from ferromagnesian minerals of mafic igneous source provenance and oceanic island arc region. Average concentrations of designated trace elements in the studied sandstones are low in concentrations. The lower concentrations of Cr, Co, and Ni and higher concentrations of Zr, Ba, and Sr suggest a felsic progenitor rock. But significantly high values of Ni (7.02 ppm), La/Co (7.99), and Ni/Co (3.28) as well as the low concentration value of Y, (3.23 ppm) suggests contributions from mafic source rocks. Low average ratios for La/Co, Th/Co, Th/Sc, Ni/Co, Cr/Ni, Cr/Sc, Cr/Th, Ni/Co, Cr/Ni, Cr/Th, Cr/Sc, Th/Sc, La/Co and Th/Co also suggest a felsic source provenance. An average CIA value of 78.04% is indicative of an intense recycling in the source area while an average MIA value of 56.13% suggests a moderate degree of weathering. The high clay matrix and feldspar content have been used to classify the sandstones as feldspathic greywackes deposited in dry arid climatic conditions under a basement uplifted tectonic setting.   


2013 ◽  
Vol 64 (1) ◽  
pp. 23-38 ◽  
Author(s):  
Marek Vďačný ◽  
Anna Vozárová ◽  
Jozef Vozár

Abstract The Permian sandstones of the Malužiná Formation in the northern part of the Malé Karpaty Mts are dominantly quartzofeldspathic and quartzolithic in composition with abundant feldspars and volcanic, plutonic igneous and less metasedimentary lithic fragments, indicating the sand grains were derived from a basement uplift and recycled orogen. The Malužiná Formation sandstones have moderate to high SiO2 contents (68-85 wt. %; on average 76 wt. %), TiO2 concentrations averaging 0.3 wt. %, Al2O3 contents of about 12 wt. %, and Fe2O3 (total Fe as Fe2O3) + MgO contents of around 2.9 wt. %. The Chemical Index of Alteration (CIA) values for the Permian Malužiná Formation sandstones vary from 45 to 68 with an average of 55, indicating low to moderate weathering of the source area. The bulk chemical composition and selected trace elements preserve the signatures of a felsic and intermediate igneous provenance, and suggest mostly an active continental margin tectonic setting of the source area for the Malužiná Formation sandstones. The Eu/Eu* (~0.78), La/Sc (~7.28), Th/Sc (~2.10), La/Co (~6.67), Th/Co (~1.85), and Cr/Th (~6.57) ratios as well as the chondrite-normalized REE patterns with flat HREE, LREE enrichment, and negative Eu anomalies indicate derivation of the Malužiná Formation sandstones from felsic rock sources. The deposition of the Malužiná Formation sandstones took place in a rifted continental margin environment supplied from collision orogen on a thick continental crust composed of rocks of older fold belts.


2019 ◽  
pp. 1498-1506
Author(s):  
Mustafa Najm Al-Shamary ◽  
Mazin Yousif Tamar-Agha

     The purpose of this study is to determine the mineralogical composition of Lower Diyala River, northeastern of Baghdad, and attempt to define the sources of sediments. 10 samples were collected from Lower Diyala River from the area between Himreen Dam to south Baghdad, where these samples are dealings by the heavy liquid to separated into light and heavy minerals. The light minerals contents are composed mainly of quartz, feldspars, and rock fragments. The main rocks fragments consist of; igneous, metamorphic, carbonate, chert rock fragments, and evaporites. The heavy minerals contents are opaques minerals, chlorite, amphiboles, pyroxenes, epidote, zircon, garnet, muscovite, biotite, kyanite, tourmaline, staurolite, and rutile. The source area of these sediments is the outcrops of Upper Miocene-Pliocene rocks at the northeastern part of the studied area, igneous, and metamorphic rocks in the northeastern Iraq and Iran.


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