scholarly journals PETROLOGICAL CHARACTERISTICS OF CLASTIC SEDIMENTARY ROCKS FROM THE ST. BARBARA ORE MINE IN RUDE NEAR SAMOBOR

2021 ◽  
Vol 36 (1) ◽  
pp. 121-135
Author(s):  
Šime Bilić ◽  
Vesnica Garašić
Keyword(s):  
Iron Ore ◽  
Sedimentary Rocks ◽  
Source Rocks ◽  
Chemical Index ◽  
Quartz Arenite ◽  
Petrographic Analyses ◽  
Chemical Index Of Alteration ◽  
Geochemical Analyses ◽  
Clastic Sedimentary ◽  
Very High

In the scope of this research, the petrographic and geochemical analyses of clastic sedimentary rocks from the St. Barbara, copper and iron ore mine in Rude near Samobor, have been made, aiming to classify and determine the provenance and environment of formation of clastic sedimentary rocks, as well as the influence of hydrothermal fluids on their properties. Eight samples were collected in total from different locations in the mine. Six of those samples have been studied in detail. The results showed structural and geochemical variability and uneven hydrothermal alteration intensity in the samples. Based on petrographic analyses, three rocks are classified as sublithoarenite, quartz arenite and quartz greywacke. Three of the samples are classified as ore breccia, ore sandstone, and ore silt-sandstone due to the pronounced hydrothermal alterations and ore mineralisation. Comprehensively, petrographic and geochemical analyses indicate that the source rocks of the investigated clastic sedimentary rocks were felsic (La/Sc = 0.9-6.2; Th/Sc = 1.3-2.4), most probably sedimentary, possibly resedimented rocks. The extent of source rock weathering was very high (Chemical Index of Alteration CIA = 52.1 - 81.3 %) and the geotectonic position of the sedimentary basin was very likely to be at the passive continental margin.

The lower Proterozoic Fern Creek Formation, northern Michigan: mineral and bulk geochemical evidence for its glaciogenic origin

2002 ◽  
Vol 39 (4) ◽  
pp. 481-492 ◽  
Author(s):  
Anne Argast
Keyword(s):  
Rare Earth ◽  
Chemical Weathering ◽  
Chemical Index ◽  
Quartz Arenite ◽  
Bulk Chemical ◽  
Chemical Index Of Alteration ◽  
Rare Earth Mineral ◽  
Chemical Trends ◽  
Northern Michigan ◽  
Bulk Chemistry

Bulk chemical data indicate the Fern Creek Formation (Early Proterozoic, Marquette Range Supergroup, Lower Chocolay Group) originated as a glacial till, resolving an old argument about the correct interpretation for diamictite-containing units within the formation. There are poor correlations among SiO2, Al2O3, and K2O, and the chemical index of alteration averages 55. These are qualities characteristic of tills and other sediments accumulated in the absence of chemical weathering and transport-induced sorting and inconsistent with an origin as a fluvial deposit (the principal alternate hypothesis). The Archean Carney Lake Gneiss might be the source for at least the lower portions of the Fern Creek Formation. Compositions are similar, and rare earth element trends in the Fern Creek Formation are consistent with derivation from an Archean high-grade terrane. Pegmatites in the gneiss could be the source for monazite, huttonite, and an unnamed fluor-hydroxy-rare earth mineral that occurs in the midsection of the Fern Creek Formation. In addition, mineral and bulk chemical trends are consistent with models involving deep erosion of a complex Archean source, similar to models previously developed for Gowganda tills in the Huronian Supergroup. Samples of the Sturgeon River Quartzite occurring above the Fern Creek Formation were also analyzed. The bulk chemistry is consistent with a well-sorted, supermature quartz arenite.

scholarly journals Sedimentary petrological characteristics of lateral and frontal moraine and proglacial glaciofluvial sediments of Bertilbreen, Central Svalbard

2011 ◽  
Vol 1 (1) ◽  
pp. 11-33 ◽  
Author(s):  
Martin Hanáček ◽  
Jan Flašar ◽  
Daniel Nývlt
Keyword(s):  
Sedimentary Rocks ◽  
Rock Avalanche ◽  
Middle Part ◽  
Source Rocks ◽  
Ice Age ◽  
Lateral Moraine ◽  
Material Sources ◽  
The Right ◽  
Clastic Sedimentary ◽  
The Impact

Bertilbreen is a valley glacier located in the central part of the Spitsbergen Island, Svalbard. Glacier bedrock is composed of Devonian Old Red facies sedimentary rocks, Carboniferous clastic sedimentary rocks and Carboniferous to Permian limestones. Cobble clasts from the right-hand lateral moraine, frontal moraine and proglacial glaciofluvial sediments were studied. The upper part of the lateral moraine is composed mostly of passively transported supraglacial debris (originally unmodified scree, snow and scree/rock avalanche deposits) with a small proportion of actively transported clasts or reworked glaciofluvial sediments. Clasts in the middle part of the lateral moraine originate predominantly from the frontal moraine of a small glacier in the lateral valley. The lower part of the lateral moraine and frontal moraine of Bertilbreen are rich in subglacially transported material, which is supported by isometric clast shapes, roundness degree and common clast surface striations. Coarse gravel forms longitudinal bars in the glaciofluvial stream flowing from the glacier front. In the southern mouth of the valley, the proglacial stream grades into a braided outwash fan. Clast nature is affected by the source from the surrounding glacial deposits and bedrock outcrops, the impact of glaciofluvial transport on the clast nature increases in the braided outwash fan. Clast shapes are primarily influenced by bedding and fractures of source rocks, but are also significantly influenced by the type and proximity of material sources. Striation is cleared away the clast surface during the glaciofluvial transport. A morphostrati-graphically older glaciofluvial terrace formed by glaciofluvial sediments deposited during the glacier advance culminating during the Little Ice Age (LIA) is located at the southern end of the valley. The comparison of active proglacial stream sediments and those from older glaciofluvial terrace was done using the coarse pebble fraction.

PROVENANCE, TEXTURE, AND RELATIVE AGE CONTROLS ON THE CHEMICAL INDEX OF ALTERATION (CIA) IN PLEISTOCENE TILLS, MINNESOTA USA

2018 ◽  
Author(s):  
Chad Wittkop ◽  
◽  
Christian Piper ◽  
Julie K. Bartley ◽  
Russell Krueger ◽  
...  
Keyword(s):  
Relative Age ◽  
Chemical Index ◽  
Chemical Index Of Alteration

Deep fluids and their role in hydrocarbon migration and oil deposit formation exemplified by supercritical СO2

2021 ◽  
pp. 1-11
Author(s):  
Sara LIFSHITS
Keyword(s):  
Supercritical Fluid ◽  
Oil And Gas ◽  
Gas Permeability ◽  
Sedimentary Rocks ◽  
Source Rocks ◽  
Reservoir Properties ◽  
Hydrocarbon Migration ◽  
Geological Processes ◽  
Before And After ◽  
Oil Source

ABSTRACT Hydrocarbon migration mechanism into a reservoir is one of the most controversial in oil and gas geology. The research aimed to study the effect of supercritical carbon dioxide (СО2) on the permeability of sedimentary rocks (carbonates, argillite, oil shale), which was assessed by the yield of chloroform extracts and gas permeability (carbonate, argillite) before and after the treatment of rocks with supercritical СО2. An increase in the permeability of dense potentially oil-source rocks has been noted, which is explained by the dissolution of carbonates to bicarbonates due to the high chemical activity of supercritical СО2 and water dissolved in it. Similarly, in geological processes, the introduction of deep supercritical fluid into sedimentary rocks can increase the permeability and, possibly, the porosity of rocks, which will facilitate the primary migration of hydrocarbons and improve the reservoir properties of the rocks. The considered mechanism of hydrocarbon migration in the flow of deep supercritical fluid makes it possible to revise the time and duration of the formation of gas–oil deposits decreasingly, as well as to explain features in the formation of various sources of hydrocarbons and observed inflow of oil into operating and exhausted wells.

scholarly journals Provenance of sediments from Barra del Tordo and Tesoro beaches, Tamaulipas State, northwestern Gulf of Mexico

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Mayla A. Ramos-Vázquez ◽  
John S. Armstrong-Altrin
Keyword(s):  
Gulf Of Mexico ◽  
Age Groups ◽  
Source Area ◽  
Detrital Zircons ◽  
Sediment Provenance ◽  
Geochemical Composition ◽  
Chemical Index ◽  
Beach Sediments ◽  
Chemical Index Of Alteration ◽  
Ree Patterns

AbstractThe mineralogy, bulk sediment geochemical composition, and U–Pb ages of detrital zircons retrieved from the Barra del Tordo (Tordo) and Tesoro beach sediments in the northwestern Gulf of Mexico were analyzed to determine their provenance. The beach sediments are mainly composed of quartz, ilmenite, magnetite, titanite, zircon, and anorthite. The weathering proxies such as the Chemical Index of Alteration (CIA), Chemical Index of Weathering (CIW), and Plagioclase Index of Alteration (PIA), reveal a moderate-to-high intensity of weathering in the source area. The chondrite-normalized rare earth element (REE) patterns are similar to felsic igneous rocks, with large negative europium anomaly (Eu/Eu* = ~ 0.47–0.80 and ~ 0.57–0.67 in the Tordo and Tesoro beach sediments, respectively).Three major zircon U–Pb age groups are identified in the Tordo and Tesoro beach sediments, i.e., Proterozoic (~ 2039–595 Ma), Mesozoic (~ 244–70.3 Ma), and Cenozoic (~ 65.9–1.2 Ma). The differences of the zircon age spectrum between the Tordo and Tesoro beach sediments are not significant. The comparison of zircon U–Pb ages in this study with ages of potential source terranes suggests that the Mesozoic and Cenozoic zircons of the studied Tordo and Tesoro beach sediments were derived from the Eastern Alkaline Province (EAP) and Mesa Central Province (MCP). Similarly, the likely sources for the Proterozoic zircons were the Sierra Madre Oriental (SMOr) and Oaxaquia in the northwestern Gulf of Mexico. The results of this study further indicate that the sediments delivered to the beaches by rivers and redistributed by longshore currents were crucial in determining the sediment provenance.

Factors dominating deterioration of clastic sedimentary rocks

2011 ◽  
pp. 939-944
Author(s):  
P Chan ◽  
S Lyu ◽  
T Wang ◽  
F Jeng ◽  
T Ueng
Keyword(s):  
Sedimentary Rocks ◽  
Clastic Sedimentary

scholarly journals X-RAY FLUORESCENCE AND STABLE ISOTOPES ANALYSES OF IKPESHI MARBLE, SOUTH SOUTHERN NIGERIA

2020 ◽  
Vol 10 ◽  
pp. 102
Author(s):  
Phillips Reuben Ikhane ◽  
Olalekan Olayiwola Oyebolu ◽  
Afolabi Omotayo Alaka
Keyword(s):  
Stable Isotopes ◽  
Stable Isotope ◽  
Precipitation Process ◽  
Dolomitic Marble ◽  
X Ray ◽  
Humid Condition ◽  
Major Oxides ◽  
Chemical Index ◽  
Isotopic Analyses ◽  
Chemical Index Of Alteration

Integration of X-ray fluor escence and stable isotope spectrometric techniques for quality assessment and provenance study of exposed marble deposit at Fakunle Quarry, Ikpeshi, South Western Nigeria constitute the fundamental aims of this research. Fourteen fresh (14) marble samples obtained at different localities within the quarry were subjected to geochemical and isotopic analyses to ascertain the quantitative abundance of major oxides and stable isotopes using X-Ray Fluorescence and Thermo Fisher mass spectrometer respectively. The major oxides revealed by XRF analysis of the marble samples are CaO, MgO, SiO2, Al2O3, Fe2O3 and Na2O with percentage composition ranging between 11.66 – 13.25, 7.75 – 9.65, 41.36 – 47.55, 12.36 – 15.23, 7.79 – 10.55 and 1.44 – 1.75respectively. Na2O + K2O value ranges between 1.48 and 1.78.The classification of marble in relation to percentage of calcite-dolomite indicate a percentage range of -5 to 4% and 93-103% for Calcite and Dolomite respectively. Chemical Index of Alteration (CIA) ranges from 45.16 to 51.59 % and Chemical Index of Weathering (CIW) ranges from 46.19 to 52.30 %. Stable isotope ( ? –180) of marble ranges from -10.50 to -7.00 with a corresponding value from 25.50 to 55.33.Interpretation of the overall results indicates an impure quartz-rich dolomitic marble; metamorphosed from a low carbonate sedimentary/meta sedimentary protolith which shallowly precipitated within a passive marginal marine environment under humid condition. The high silica impurity can however be attributed to the inordinate influx of terrigenous sediments during the precipitation process. Weathering effect is minimal on the marble deposit. Conclusively, strong correlation is apparent between the obtained geochemical result and the basement geology of the study area.

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