Mineral Content Of Rocks Research Articles

Analisis Pengaruh Mineral terhadap Nilai Kuat Tekan Batuan

To determine the mineral content and composition of a rock, a petrographic test is carried out using a thin section method. Petrographic test is known as an efficient test of time and energy with accurate results in obtaining the composition and mineral content of rocks. The Point Load test is an index test that has been widely used to predict the UCS value of a rock indirectly in the field. This is due to the simple test procedure, easy sample preparation and can be done in the field, so that the strength of the rock can be quickly known in the field before testing in the laboratory.

Hydrogen-water-rock interaction from the perspective of underground hydrogen storage: Micromechanical properties and mineral content of rock

Underground hydrogen storage (UHS) in depleted oil and gas reservoirs is recognized as the most promising large-scale hydrogen storage method. The hydrogen-water-rock interaction during the long-term storage of hydrogen is an important factor affecting the long-term stability of the formation and evaluating the effect of hydrogen storage. This study focuses on the influence of hydrogen-water-rock interaction on the micromechanical properties and mineral content of different rocks in the process of UHS, compares the differences in the influence of gas medium and water content characteristics on rock properties, and then evaluates the best hydrogen storage conditions. Hydrogen-water-rock interaction can significantly improve the microscopic mechanical properties of rocks and enhance the stability of reservoirs and cap rocks, which is beneficial for long-term hydrogen storage. H2O and H+ are important media for the reaction of H2 with rocks, which can promote the reaction and dissolution of some silicate minerals (such as clay and feldspar) and carbonate minerals. However, H2O and CH4 are more likely to be adsorbed on the surface of hydrophilic inorganic minerals to form water film and gas film, hindering the direct contact of H2 with minerals, which reduces the reaction intensity of hydrogen with rocks, indicating a decrease in hydrogen loss. Compared with sandstone, shale contains a large amount of organic matter and clay. H2 and CH4 will preferentially be adsorbed on the surface of the pores of these substances, reducing the content of hydrogen that contacts and reacts with inorganic minerals, so the reaction intensity of shale is generally weaker than that of sandstone. Considering the influence of hydrogen-water-rock interaction on rock properties and hydrogen loss during long-term hydrogen storage, depleted shale gas reservoirs with less water content and cushion gas such as CH4 may be a better large-scale UHS method than conventional depleted gas reservoirs. This work helps to screen the optimal hydrogen storage conditions and provides a reference for the site selection and construction of UHS in depleted oil and gas reservoirs.

Factor Analysis of XRF and XRPD Data on the Example of the Rocks of the Kontozero Carbonatite Complex (NW Russia). Part II: Geological Interpretation

Numerical comparison of mineralogical and geochemical data, which is required in a variety of geological applications, is a challenging task, especially when analyzing extensive sample collections. Herein, we apply factor analysis (FA) to a collection of 198 diffraction patterns of bulk rock samples from the Kontozero carbonatite complex. The mineralogical information hidden in the X-ray powder diffraction (XRPD) data is thereby squeezed down to a set of two dozen variables represented by factor scores (FS). The values of these FSs show a functional relationship with the contents of the minerals composing the rocks. Therefore, factor scores can be considered as a beneficial tool for rapid qualitative and semiquantitative analysis of the mineral composition of rocks. Supplementing principal component analysis (PCA) with FSs as independent variables characterizing the mineral content of rocks allows for the numerical comparison of mineralogical and geochemical data. By PCA, we reveal the main trends in the mineralogical and geochemical evolution of the investigated rocks of the Kontozero complex. Furthermore, the results are obtained in the very first stages of the research. This fact elucidates the potential use of the proposed technique in geological studies and mining.

Arid Environment and Rock Mineral Content as a Catalyst for Higher Vulnerability to Cancer Morbidity in the Northern State of Sudan

This study is based on the statement that arid environment and type of mineral content of rocks work together as a catalyst for absorption of higher rates of solar irradiation that will inevitably ...

Influence of Hydrothermal and Pyrolysis Processes on the Transformation of Organic Matter of Dense Low-Permeability Rocks from Domanic Formations of the Romashkino Oil Field

The model experiments regarding the conversion of organic matters from carbonate rock samples of Dankov-Lebedyan deposits of Zelenogorskaya area and siliceous-carbonate rocks of Semiluki-Mendym deposits of Berezovskaya area of Domanic formations of Romashkino oil field were carried out. Two types of experiments were carried out: (1) the hydrothermal treatment of rocks at a temperature of 350°C in the presence of carbonic acid and a water content of 30%; (2) pyrolysis at temperatures of 350 and 600°C in the presence of hydrogen. The yield and quality of extracted hydrocarbons from the rocks depending on the mineral composition of rocks, content and composition of organic matter, and thermal stability of kerogen under hydrothermal influences were evaluated. Application of electron paramagnetic resonance in pyrolysis processes revealed the difference in mineral content of rocks (Mn2+, SO3−, and SO2− ions) and free radicals R∗, as well as in vanadyl ion (VO2+) concentration. It is established that an increasing temperature of pyrolysis promotes the formation of new free organic radicals in rock samples: in Domanic rocks of Semiluki-Mendym deposits at 350°С and in carbonate rocks of Dankov-Lebedyan horizon at 600°С. This indicates different ability of oil-generating potential of rocks with hydrothermal and pyrolysis technologies.

Klasifikasi Batuan Beku Gabbro Pada Citra Sayatan Tipis Menggunakan Multilevel Otsu’s Thresholding

Citra sayatan tipis batuan merupakan metode pengaman yang digunakan untuk menentukan jenis batuan dan nama dari batuan berdasar pada mineral penyusun. Melakukan pengamatan sayatan tipis sulit dilakukan jika hanya menggunakan bantuan mikroskop polarisasi karena kemampuan mata manusia tidak dapat melakukan identifikasi secara mendetail. Oleh karena itu analisis dan identifikasi mineral menjadi lebih mudah dilakukan dengan bantuan pengolahan citra digital dengan menggunakan algoritma Multilevel Otsu’s Thresholding untuk mengetahui kelimpahan mineral batuan beku. Data yang digunakan dalam penelitian ini menggunakan citra sayatan tipis batuan beku yang diakuisisi dari penggunaan mikroskop polarisasi dengan perbesaran 10x. preprocessing yang dilakukan dengan 2 perlakuan yang berbeda yaitu garyscale dan grayscale dengan k-means untuk mengetahui hasil yang maksimal. Selanjutnya tahap pengolahan dilakukan segmentasi Multilevel Otsu’s Thresholding dengan dua nilai ambang. Selanjutnya analisis pada hasil segmentasi untuk mengetahui kelimpahan mineral. Hasil perhitungan dan analisis yang telah dilakukan pada preprocessing yang menggunakan grayscale dan grayscale dengan k-means yang kemudian di lakukan segmentasi Multilevel Otsu’s Thresholding memiliki akurasi paling tinggi 40% dan 33,57%. Dari kedua perlakuan dapat disimpulkan bahwa penggunaan k-means pada preprocessing memiliki pengaruh pada pengolahan citra sayatan tipis batuan beku jenis gabbro dengan nilai akurasi tertinggi dari dua perlakuan yaitu 40% dengan menggunakan preprocessing k-means dengan nilai k=7.

Comparative Imaging of Liquids in Rocks by NMR and Differential X Ray CT

ABSTRACTWe have applied NMR Imaging and X_Ray Computerized Tomography to the study of the structural properties of rocks. Samples from different porous rocks; sandstones, granites, limestones have been successively examined by both techniques. NMR images have been obtained on water saturated samples. The spatial distribution of liquid indicates the effective porosity. By constrast, X_Ray images display the mineral content of rocks. Standard tomographs do not have the required resolution to see pores smaller than 100 μm. We used water as a constrast agent to localize porosities by “differential” CT. Comparative results are shown.