Journal articles on the topic 'Black Rocks'
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1
Wigmore, Gillian. "Black Rocks and Sea." Geographical Review 103, no. 2 (April 1, 2013): 256–59. http://dx.doi.org/10.1111/gere.12015.
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Liao, Xin, Xi Yong Wu, and Jiang Tao Duan. "Study on the Mechanism of Water-Rock Interaction of the Black Rock Strata." Advanced Materials Research 243-249 (May 2011): 3319–24. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.3319.
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Black rock strata with special engineering geological characteristics are distributed widely in different geological periods and areas. The scattered sulfide minerals in the rock strata are changed in a short time under the action of the oxygen-rich surface water and oxygen-rich groundwater. And the acidic water with strong erosiveness is formed. Then water--rock interaction between other minerals and the acidic water subsequently occurs with a series of chemical reactions. It can affect the stability of the black rocks themselves and other non-black rocks nearby directly, and cause engineering and environmental geological problems. Through the combination of engineering project and immersion test indoor, the mechanism of water-rock interaction of the black rock strata is researched. Engineering preventions and measures in the black strata region are proposed to avoid the damage to project and the ecological environment around.
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Liu, Wenjie, Ke Yang, Wei Zhen, Xiaolou Chi, Rijie Xu, and Xin Lv. "Energy Dissipation and Failure Characteristics of Layered Composite Rocks under Impact Load." Shock and Vibration 2021 (November 15, 2021): 1–14. http://dx.doi.org/10.1155/2021/8775338.
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Horizontal layered composite rock samples composed of white and black sandstones with large differences in physical and mechanical properties were tested to explore the dynamic characteristics of layered composite rocks under impact load. Using the split Hopkinson pressure bar test system, the dynamic compression tests of two incident states of stress waves, that is, stress waves from white sandstone to black sandstone (W⟶B) and from black sandstone to white sandstone (B⟶W), were designed and carried out under different impact velocities. Combining the ultrahigh-speed photography system and digital photogrammetry for deformation measurement (DPDM), we obtained the stress wave propagation characteristics, failure characteristics, and particle size distribution characteristics of broken rocks of the composite rocks under the two conditions. The experimental results were compared and analyzed, while stresses and strength conditions at the interface of the composite rock samples were theoretically assessed, yielding the following main findings. The energy dissipation pattern of composite rock had an obvious strain rate effect. The reflected energy and fragmentation energy density of composite rock increased approximately as quadratic functions of the incident energy. Affected by the wave impedance matching relationship, the W⟶B and B⟶W samples were significantly different in terms of the stress wave shape, energy dissipation, average particle size, and fractal dimension of the broken rocks at low impact velocities. However, with an increase in the impact velocities, the two gradually shared the same behavior. When composite rock samples deformed and failed, the macrocracks mostly initiated from the white sandstone. When the crack tip stress of the white sandstone at the interface exceeded the strength of the weakened black sandstone, the crack continued to develop through the two-phase rock interface due to the difference in Poisson’s ratios. The damage degrees and failure modes of the two parts of composite rocks were different: black sandstone was prone to tensile splitting with local shear failure, while white sandstone exhibited shear failure with local tensile splitting. The damage degree of white sandstone exceeded that of black sandstone.
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Zhu, Bao Long, and Xi Yong Wu. "Weathering Process of Black Strata." Applied Mechanics and Materials 71-78 (July 2011): 1451–54. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.1451.
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Black strata is a wildly distributed and special rock, whose weathering tends to speed up the weathering and the worsening of all rocks and the construction materials. The paper, via the geochemical process of the sulphide oxidation in the black strata, is to make analysis of the weathering features of the black strata in the west of Hunan province, China; the stability of other minerals in the black strata under acid condition, as well as the effect on the weathering of the black strata by rock components, geologic formation and different movements and moving speeds of the underground water.
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Chang, Tsang-Pi. "Blue-green algae from rocks of "Black Mountain"." Algological Studies/Archiv für Hydrobiologie, Supplement Volumes 75 (October 27, 1995): 97–99. http://dx.doi.org/10.1127/algol_stud/75/1995/97.
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Rashid, Alidu, Numair Ahmed Siddiqui, Nisar Ahmed, Muhammed Jamil, Daniel Asante Otchere, and Sani Ado Kasim. "Field Characteristics of Sedimentary Rocks in the Dohol Formation, Johor, Peninsular Malaysia." IOP Conference Series: Earth and Environmental Science 1087, no. 1 (October 1, 2022): 012064. http://dx.doi.org/10.1088/1755-1315/1087/1/012064.
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Abstract The Dohol formation is predominantly composed of sedimentary rocks; however, the black shales attract much attention because of their potential to generate hydrocarbons. Black shales generally have a high organic matter content and can serve as good source rocks for hydrocarbon generation. Therefore, this study was conducted to characterize the sedimentary rocks, including the black shales, which are of great importance and discover new areas where these rocks can be located. Four distinctive lithofacies of shales were observed on the field; the massive black shales facies, light grey shales facies with quartzite intrusion in some areas, the red sandy shales, and the dark brown shales facies. The black shales are dark-coloured, laminated, and some parts are fissile. The second type of shale, light grey, looks similar to the dark shales, but it probably contains less organic matter. In other areas, these grey shales have intrusions of quartzite. The third type of shale facies are the red shales which are sandy, fissile, and highly weathered, and pebbly sands overlie it. Finally, the dark brown shale facies are fissile, flaky, and weathered. The sandstones encountered are massive cream-colored, and composed of mainly quartz with a few scour marks in some areas. Several new outcrop locations of these sedimentary rocks were discovered, and they are spread across Jemaluang, Kota Tinggi, and the outskirts of Mersing town in East Johor. From the outcrop trends and the sedimentary features of the shale rock sequence, the deposition environment of the shales is probably from shallow to deep marine.
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Saupé, Francis, and Ghislaine Vegas. "Chemical and mineralogical compositions of black shales (Middle Palaeozoic of the Central Pyrenees, Haute-Garonne, France)." Mineralogical Magazine 51, no. 361 (September 1987): 357–69. http://dx.doi.org/10.1180/minmag.1987.051.361.03.
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AbstractThe epicontinental sedimentary, epi- to mesozonal rocks of the Middle Palaeozoic of the Central Pyrenees host several economic Pb-Zn concentrations and numerous occurrences of these metals. The authors have endeavoured to recognize the original mineralogical nature of the epizonal host rocks in the concession of Baren (Haute-Garonne). Seventy-two whole-rock analyses were used for this purpose and interpreted by means of chemico-mineralogical diagrams.These diagrams use parameters chosen so as to include in the projection planes the essential minerals forming the rocks under discussion. In this way, the nature and the possible initial mineralogical composition of the rocks, which are usually obliterated during metamorphism, are made visible. The chemical compositions of the different rock units are sufficiently typical to compensate for the absence of fossils and to allow stratigraphic identifications.No volcanic contribution could be recognized in the pelites. The latter demonstrate the existence of a continent, undergoing a kaolinite-producing alteration, especially during the Silurian. The analysed trace elements (Ba, Cr, Cu, Ni, Pb, Rb, Sr, Th, U, V and Zn) are not enriched with respect to the clarkes for these rocks, except slightly in the case of U and Th and more strongly for Cr and V. The carbonate rocks contain predominantly calcite, with subordinate dolomite. They show a strong enrichment in Ba, whereas the content of the other trace elements is normal.
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Owusu, Esther B., and Haylay Tsegab Gebretsadik. "The potential of shale gas resources in Peninsular Malaysia." IOP Conference Series: Earth and Environmental Science 1003, no. 1 (April 1, 2022): 012024. http://dx.doi.org/10.1088/1755-1315/1003/1/012024.
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Abstract Even though the black shales in Peninsular Malaysia covered a quarter of the total surface area and have been overlooked for their economic potential except few workers have evaluated their thermal maturity using rock-eval pyrolysis, vitrinite reflectance analysis and illite crystallinity. According to these research works, the shales have been categorized into immature, mature and overmatured successions, which in turn dictated the exploration activities of commercially viable shale gas in the onshore Peninsular Malaysia. In this work, published and unpublished data on the scattered black shales of Peninsular Malaysia were examined to assess exploration potential of shales from various stratigraphic windows. Thus, using comparative evaluation of all the thermal history plots of the black shales from Peninsular Malaysia; areas of thermally matured source rocks are identified. According to the thermal maturation assessment; the Palaeozoic black shales in the Peninsular Malaysia have minimal generative potential for economically viable source rock for hydrocarbon, whereas the younger successions of Oligocene to Miocene have considerable potential to serve as source rocks of feasible prospect, provided permissible geological settings are met.
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Hanger, Rex Alan, and Ellen E. Strong. "Correlation of Permian Rocks of the Black Rock Terrane, Northwestern Nevada." Paleontological Society Special Publications 8 (1996): 159. http://dx.doi.org/10.1017/s2475262200001611.
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Nogami, Lizandra, Antenor B. Paraguassú, José E. Rodrigues, and Rogério P. Ribeiro. "Influence of the Mineralogical and Mortar Components on the Adherence of Some “Granites”." Key Engineering Materials 548 (April 2013): 267–74. http://dx.doi.org/10.4028/www.scientific.net/kem.548.267.
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Rock plate setting can be performed with metal inserts or by mortar adhesion. For mortar setting, the adhesion bond strength values, as a rule, should be above 1 MPa. In the present work, tests with eight types of “granite” tiles were performed to compare the adherence of five types of mortars. The rocks chosen were: Red Brasilia (syenogranite), Black Indian (migmatite), Green Labrador (charnockite), Black Sao Gabriel (hypersthene diorite), Rose Jacaranda (nebulitic migmatite syenogranite), Fantastic Blue (biotite monzogranite megaporphyritic serial gneissified), Grey Swallow (monzogranite) and Yellow Ornamental (garnet porphyroblastic gneiss), which do not have similar petrographic and sawability characteristics, thereby resulting in different initial roughness values of the plates obtained by breaking apart the blocks on the gangsaw machine, which use granulated steel as an abrasive element. The adherence of these rocks with the mortars was determined in the rough surface as well as in the polished surface by the pullout traction test, standardized for ceramics. The results showed that the mortar adhesion is related to roughness, to mineralogy and to the texture of these rocks. To verify this relationship, tensile bond strength tests were performed with the main mineral components of these rocks using single crystals with known optical orientation. Moreover, the microstructure study of the standard substrate/mortar/rock set was also performed.
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Smolarek, Justyna, Leszek Marynowski, Karol Spunda, and Wiesław Trela. "Vitrinite equivalent reflectance of Silurian black shales from the Holy Cross Mountains, Poland." Mineralogia 45, no. 3-4 (December 1, 2014): 79–96. http://dx.doi.org/10.1515/mipo-2015-0006.
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Abstract A number of independent methods have been used to measure the thermal maturity of Silurian rocks from the Holy Cross Mountains in Poland. Black shales are characterized by diverse TOC values varying from 0.24-7.85%. Having calculated vitrinite equivalent reflectance using three different formulas, we propose that the most applicable values for the Silurian rocks are those based on Schmidt et al. (2015) equation. Based on this formula, the values range from % 0.71 VReqvVLR (the vitrinite equivalent reflectance of the vitrinite-like macerals) to % 1.96 VReqvVLR. Alternative, complementary methods including Rock Eval pyrolysis and parameters based on organic compounds (CPI, Pr/n-C17, Ph/n-C18, MPI1, and MDR) from extracts did not prove adequate as universal thermal maturity indicators. We have confirmed previous suggestions that Llandovery shales are the most likely Silurian source rocks for the generation of hydrocarbons in the HCM.
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A.A, Kinsara, Shabana E.I, and Qutub M.M.T. "Natural Radioactivity in Some Building Materials Originating from a High Background Radiation Area." International Journal for Innovation Education and Research 2, no. 6 (June 30, 2014): 70–78. http://dx.doi.org/10.31686/ijier.vol2.iss6.195.
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Twenty four samples of building materials, collected from utilized quarries dispersed randomly in a high natural background radiation area, were analyzed for 226Ra, 232Th and 40K by γ-spectrometry. This area lies in Hail province, Saudi Arabia. The collected samples were fragmented granites, granite gravels with clays, sands and crushed black rocks (mafic metavolcanic rocks). The results showed that the highest activity concentrations were found in the fragmented granite materials and ranged from 144-207, 671-1058 and 964-1440 Bq/kg with average values of 194, 912 and 1320 Bq/kg for 226Ra, 232Th and 40K, respectively. The lowest activity concentrations were found in the black rock materials which ranged from 19-39, 47-125 and 212-306 Bq/kg with average values of 24, 82 and 255 Bq/kg for 226Ra, 232Th and 40K, respectively. The radioactivity levels in the other materials lie somewhere in between. Granites and clays exceeded the proposed hazard indices for the usage as building materials and should be restricted, whereas the sands and the crushed black rocks complied with these indices and can be used without restrictions.
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Tan, Yunliang, Dongmei Huang, and Ze Zhang. "Rock Mechanical Property Influenced by Inhomogeneity." Advances in Materials Science and Engineering 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/418729.
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In order to identify the microstructure inhomogeneity influence on rock mechanical property, SEM scanning test and fractal dimension estimation were adopted. The investigations showed that the self-similarity of rock microstructure markedly changes with the scanned microscale. Different rocks behave in different fractal dimension variation patterns with the scanned magnification, so it is conditional to adopt fractal dimension to describe rock material. Grey diabase and black diabase have high suitability; red sandstone has low suitability. The suitability of fractal-dimension-describing method for rocks depends on both investigating scale and rock type. The homogeneities of grey diabase, black diabase, grey sandstone, and red sandstone are 7.8, 5.7, 4.4, and 3.4, separately; their average fractal dimensions of microstructure are 2.06, 2.03, 1.72, and 1.40 correspondingly, so the homogeneity is well consistent with fractal dimension. For rock material, the stronger brittleness is, the less profile fractal dimension is. In a sense, brittleness is an image of rock inhomogeneity in macroscale, while profile fractal dimension is an image of rock inhomogeneity in microscale. To combine the test of brittleness with the estimation of fractal dimension with condition will be an effective approach for understanding rock failure mechanism, patterns, and behaviours.
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Zakharikhina, Lalita, Yury Litvinenko, Alexey Ryndin, Ruslan Saburov, Sergey Shevelev, and Georgy Vareljyan. "Geochemical Characterization of Natural Groundwater on the Southern Slopes of the Caucasus Mountains on the Russian Black Sea Coast." Water 14, no. 14 (July 8, 2022): 2170. http://dx.doi.org/10.3390/w14142170.
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The Mzymta and Sochi watersheds, located on the southern slopes of the Caucasus Mountains on Russia’s Black Sea coast, are characterized by a remarkably complex geological setting. The predominant rocks are mudstones, siltstones, and shales, with smaller amounts of carbonate and clay-carbonate rocks, and occasionally igneous rocks. The area is also characterized by the occurrence of polymetallic, gold, sulfide, rare metal, and rare-earth mineralizations in addition to hosting a thermal hydrogen sulfide groundwater aquifer. The objective of this study was to determine groundwater genesis patterns in an area with such contrasting geological and hydrogeological structures. Based on the chemical analysis of 33 natural groundwater springs, five chemical types of water were identified dictated by the composition of the host rock as well as the occurrence of mineralizations, seepage of mineralized water, and local geochemical features of the host rock. The high sodium concentration and mineralization of groundwater near the thermal hydrogen sulfide groundwater aquifer are due to the infiltration of seawater. The consistent presence of excessive amounts of rare-earth elements (REEs) in all groundwaters in the area is a reflection of the regional geochemical specialization of the rocks. Groundwater, like the terrestrial components of the natural environment, inherits rare-earth fractionation patterns from the rocks that make up the area. Thus, rare-earth totals and fractionation patterns can be used as a reliable criterion to interpret the regional specificity of groundwater.
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Mulyanto, Djoko, and S. Surono. "Pengaruh Topografi dan Kesarangan Batuan Karbonat terhadap Warna Tanah pada Jalur Baron-Wonosari Kabupaten Gunungkidul, DIY." Forum Geografi 23, no. 2 (December 20, 2009): 181. http://dx.doi.org/10.23917/forgeo.v23i2.5010.
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Western part of the East Jawa Southern Mountains, which is distributed from Parangtritis, Yogyakarta to Pacitan Bay is the Gunung-Sewu Hills. The carbonate rocks on the Baron-Wonosari transect has some litofacies, and the soils overlying the rocks show some color varieties. Topography of Baron-Wonosari transect can be divided into two areas: southern part (Baron-Mulo) and northern part (Mulo-Wonosari). The southern part is a hilly land, whereas the northern part is a lowland plain. Soils on the southern part are dominated by red soils group, whereas on the northern part dominated by black soils group. The phenomenon is very interesting to be studied. The aim of research was to study relationship of soil colour with topography and pores of underlying carbonate rocks. Methods consist of landform especially topography observation, and soil colour by Munsell Soil Colour Chart, whereas laboratory analysis namely micro porosity and geochemical of carbonate rock. The results showed that micro pores of rocks have no effect to the soil colour formation. However, secondary pores (macro and mega) be suggested influent on red soil formation. Concentration of iron (Fe) and mangan (Mn) elements of carbonate rock have no effect on the formation of soil colour. Topography and rock secondary porosity be estimated have a role as controlling factors on the formation of soil colour by leaching process mechanism. An area, which has a high leaching capacity tend to be found much of red soils, whereas an area which has a low leaching capacity will be formed black soils.
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Cousineau, Pierre A., and Pierre St-Julien. "Stratigraphie et paléogéographie d'un bassin d'avant-arc ordovicien, Estrie-Beauce, Appalaches du Québec." Canadian Journal of Earth Sciences 31, no. 2 (February 1, 1994): 435–46. http://dx.doi.org/10.1139/e94-040.
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Two new formations, the Frontière and Etchemin formations, have been found to lie below the Beauceville and Saint-Victor formations, the two known formations of the Magog Group. The Frontière Formation, at the base of the group, is made up of centimeter-thick beds of medium- to coarse-grained litharenite and of greyish green mudstone; the sandstone, greyish green, contains abundant felsic volcanic rock fragments and chromite grains. The Etchemin Formation is composed mostly of centimeter-thick dusky yellow green siliceous mudstone; at the base, there is also a purple mudstone, and meter-thick beds of dusky green volcaniclastic rocks rich in intermediate to felsic volcanic rock fragments and crystals of feldspar and quartz occur near its top. The Beauceville Formation consists of interbedded centimeter-thick beds of black clayslate and centimeter- to meter-thick beds of black volcaniclastic rocks. The Saint-Victor Formation consists of classic turbidite beds with few meter-thick yellowish volcaniclastic rock beds similar to those of the Beauceville Formation; the sandstone is a litharenite rich in quartz grains and sedimentary rock fragments. Most rocks of the Frontière and Etchemin formations as well as the volcaniclastic rocks of the Beauceville and Saint-Victor formations were derived from a magmatic arc located to the southeast. However, the shale of the Beauceville Formation and the turbidites of the Saint-Victor Formation were derived from an orogenic source located to the northwest. The Magog Group is located between the Saint-Daniel Mélange and the Ascot Complex interpreted as remnants of an accretionary prism and a magmatic arc, respectively. The sediments of this group were thus deposited in a fore-arc basin active during the Taconian orogeny of the Middle to Late Ordovician.
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Frost, Carol D., and Fabio A. Da Prat. "Petrogenetic and tectonic interpretation of strongly peraluminous granitic rocks and their significance in the Archean rock record." American Mineralogist 106, no. 8 (August 1, 2021): 1195–208. http://dx.doi.org/10.2138/am-2022-8001.
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Abstract Strongly peraluminous granitic rocks (SPG), defined by an aluminum saturation index ≥1.1, become abundant in the rock record in the Neoarchean. This study identifies three different varieties of Neoarchean SPG in the Archean Wyoming Province, U.S.A. These include calcic SPG, represented by the Webb Canyon Gneiss and Bitch Creek Gneiss of the Teton Range; calc-alkalic to alkali-calcic suites composed entirely of SPG, including the Rocky Ridge garnet granite gneiss of the northern Laramie Mountains and the Bear Mountain granite in the Black Hills; and calc-alkalic to alkali-calcic suites that include both weakly and strongly peraluminous granitic rocks, such as the Mount Owen batholith, Wyoming batholith, and Bears Ears granite. Although the petrogenesis of all the SPG suites involves partial melting of crustal sources, the composition of those sources, the melting conditions, and the tectonic settings vary. The calcic suites originate by dehydration melting or water excess melting of hornblende-plagioclase rocks at relatively high temperature. The suites composed entirely of SPG formed by partial melting of metasedimentary rocks by reactions involving muscovite at lower temperatures. Suites with both weakly and strongly peraluminous granite may form by partial melting of metasedimentary rocks by reactions involving biotite or by assimilation of aluminous melts of felsic crust by differentiated calc-alkalic magma. Most of the Wyoming SPG appear to have formed in collisional orogens, but SPG of the Wyoming batholith and Bears Ears granite are associated with continental arc magmatism. The appearance of SPG in the Neoarchean rock record marks the time when subduction enabled the formation of strong, thick, increasingly felsic continental crust, which in turn allowed the development of a mature, clastic sedimentary cover. Lateral movement of crustal blocks led to collisional orogeny, SPG magma genesis, and the formation of the first supercontinents.
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Christiansen, F. G., and H. Nøhr-Hansen. "The Silurian shales of central and western North Greenland: evaluation of hydrocarbon source rock potential." Rapport Grønlands Geologiske Undersøgelse 143 (December 31, 1989): 47–71. http://dx.doi.org/10.34194/rapggu.v143.8057.
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The Silurian shales of central and western North Greenland form a more than 400 m thick succession which contains some potential hydrocarbon source rock intervals. Deposition of these organic-rich units was restricted in both time and space and potential source rocks only formed when and where black shales covered wide areas of sballow-water carbonates. Such deposition started in the middle Llandovery in Washington Land and continued tboughout the region in the late Llandovery. Neither the Wenlock nor the Ludlow shales contain sufficient organic matter to be considered as potential source rocks. The potential source rocks are dominated by oil-prone organic matter (large amorphous kerogen particles, mainly type Il) and typically show TOC values between 2% and 6%. The generative potential of immature to early mature samples is high with values up to 30 mg Hag rock. A drastic increase in thermal maturity of surface rocks is observed from south to north and most of the potential drainage area is thermally mature to postmature. This leaves only few chances of finding trapped hydrocarbons sourced by Silurian shales in North Greenland.
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Guo, Qiang, Da Kang Zhong, Yu Lin Wang, and Yan Chun Zhong. "Characteristics of Petroleum Geology and Prediction of Favorable Areas in Jiufotang Formation, Kazuo Basin." Advanced Materials Research 361-363 (October 2011): 3–7. http://dx.doi.org/10.4028/www.scientific.net/amr.361-363.3.
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Through the research on actual measurement 106km geological profile, the hydrocarbon source rocks mainly develop the third member of Jiufotang formation, followed by the second member. There are five distribution areas where have been divided hydrocarbon source rocks thickness is more than 400m in study area. Among them, Jiufotang area has the greatest sedimentary thickness of hydrocarbon source rocks, while Siguanyingzi-Sanjiazi area has the largest area where hydrocarbon source rocks are more than 400m. Oil shale is good hydrocarbon source rock, while dark gray and black gray mudstone (or shale) are relatively poor. The fan delta front subaqueous distributary channel and mouth bar are well-developed in basin’s fault zone and also the important favorable reservoir, followed by braided delta front mouth bar, subaqueous distributary channel and distal bar developing in northwestern area of the basin. There are four forms of source-reservoir-cap combination: (1) hydrocarbon source rock in the above layer and reservoir in the below layer; (2) hydrocarbon source rock and reservoir in the same layer; (3) normal form; (4) fingerlike intersection. The combination of fingerlike intersection is the most important forms in study area. Fan delta facies next to lacustrine facies is favorable exploration area.
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Zhang, Jie, En Lin Yang, Yong Ning Di, Fei Xie, and Guo Feng Yang. "Study of Material Characteristics about Lower Cambrian Black Shale in ZhiJin-KaiYang-XiFeng, Guizhou." Applied Mechanics and Materials 170-173 (May 2012): 1162–66. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.1162.
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The high cambrian black rock series of clay under Zhijin, Kaiyang, Xifeng and other areas of Guizhou , are high carbon black shale - clay rocks characterized by containing illite ores[1]. After deep processing, it will be served as illite ores belonging to a useful clay minerals, and the main directions of development and application include filler, new building materials and ceramics. After the activation, potassium can be extracted from illite that is often rich in potassium which can be prepared for potash fertilizer. Carrying out the study of mineral material science of high carbon black clay mineral rock , the aim is developing and using this type of non-metallic mineral. Based on this study, recoverying useful metal elements by exploring the reasonable technical process will be significant to enhance the comprehensive value of the type of deposit and improve its economic efficiency.
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Popp, Ihor, Petro Moroz, and Mykhaylo Shapovalov. "Lithogeochemistry of black shales of the Phanerozoic of the Western Ukraine ‒ unconventional hydrocarbon reservoirs." Geology and Geochemistry of Combustible Minerals 1-2, no. 187-188 (2022): 82–102. http://dx.doi.org/10.15407/ggcm2022.01-02.082.
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The purpose of this work is to compare the lithological, geochemical and mineralogical features of carbonaceous clayey and siliceous-clay rocks of Cretaceous-Paleogene flysch of the Ukrainian Carpathians and Lower Silurian of the Volyn-Podillya edge of the East European Platform and to determine the factors that contributed to the formation of zones of “unconventional reservoirs” in these sedimentary strata of cracked and mixed types. Data from the lithology, geochemistry and mineralogy of bituminous siliceous-clay rocks and siliceous rocks of Lower Cretaceous and Oligocene of the Carpathians and black argillites of Lower Silurian of the Volyn-Podillya edge of the East European Platform are presented. Sedimentogenesis of Lower Cretaceous and Oligocene bituminous deposits of the Carpathians and Lower Silurian deposits of Volyn-Podillya took place in anoxic conditions (phases of oceanic anoxic events: OAE-1 (Barrem–Albian), OAE-4 (Oligocene) and at the border of Ordovician and Silurian. Paleoceanographic conditions of their sedimentation differed significantly. The first are deep-sea formations at the foot of the continental slope of the Carpathian segment of the Tethys Ocean, the second were accumulated in the warm shallow sea on the eastern shelf of the West European Sea Basin. The layered texture of carbonaceous deposits, as well as the catagenetic transformation of rock-forming clay and siliceous minerals and their hydrophobization, played a significant role in the formation of the filtration capacity properties of “unconventional reservoirs”. In Cretaceous-Paleogene flysch deposits of the Carpathians, “unconventional reservoirs” are usually terrigenous-clay or siliceous-clay rocks with shale and layered texture or compacted sandstones localized in conventional oil, gas or condensate deposits. Lower Silurian clay deposits of Volyn-Podillya are promising for the search for “shale gas”.
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Kozhoukharov, Dimitar, Emil Vasilev, and Evgenia Kozhoukharova. "Lithostratigraphy of the Ordovician System in the Lozen Mountain." Geologica Balcanica 33, no. 3-4 (December 30, 2003): 3–14. http://dx.doi.org/10.52321/geolbalc.33.3-4.3.
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In the Lozen Mountain the rocks of the Ordovician System differ from the Ordovician rocks in the western Balkan Mts. in their composition, structure and relationship to the underlying diabase-phyllitoid complex. In the present paper they are described as a formal lithostratigraphic unit named Kroushovitsa Formation, which comprises four members. In ascending order these members are: Souha Gabra Member comprising metaconglomerates, meta-psammites with fragments of green schists, meta-tuffs and quartzites of the diabasephyllitoid complex; Choukite Member built of graygreenish phyllitized siltstones; Chouchouralchal Member comprising red phyllitized siltstones intercalated with yellow to light red meta-psammites, and Kitka Member represented by gray-greenish phyllitized siltstones intercalated with lamina of dark-gray to black argillites and siltstones. All rock varieties in the Kroushovitsa Formation have been subjected to week metamorphic alteration in greenschist facies that progressively attenuates from the lower to the upper levels of the section. The rock composition, structure and texture of the sequence in the Kroushovitsa Formation indicate for predominantly deep-sea sedimentation. In the lower part of the formation coarse clastic rocks indicate a shallowwater shelf environment.
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Malo, Michel, Pierre A. Cousineau, Paul E. Sacks, J. FV Riva, Esther Asselin, and Patrice Gosselin. "Age and composition of the Ruisseau Isabelle Mélange along the Shickshock Sud fault zone: constraints on the timing of mélanges formation in the Gaspé Appalachians." Canadian Journal of Earth Sciences 38, no. 1 (January 1, 2001): 21–42. http://dx.doi.org/10.1139/e00-072.
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Mélanges are common in the Humber and Dunnage zones of the Quebec Appalachians. Humber Zone mélanges are spatially associated with Taconian nappes and believed to be of tectonic origin. Dunnage Zone mélanges are interpreted as relicts of an Ordovician accretionary prism. The Ruisseau Isabelle Mélange (RIM) in the Gaspé Appalachians was first interpreted as a Dunnage Zone mélange, because of its tectonic position along the Baie Verte Brompton Line and lithological components, such as dark mudstone, blocks of ultramafic rocks, and greenish chromite-bearing sandstone. The RIM comprises sedimentary rock assemblages (Composite Shale, Black Shale, and Chromite-Bearing Sandstone assemblages), an Exotic Block, a Pebbly Mudstone Assemblage and slivers of Serpentinized Peridotite, and Metamorphic Tectonite. Most mélanges of the Dunnage Zone in the Quebec Appalachians contain partly similar rocks, but their age is not well constrained. Recent work on the RIM and Cap-Chat Mélange of the Humber Zone and new fossil finds in the RIM rock assemblages allow us to conclude that previous distinction between mélanges of the Dunnage and Humber zones on the basis of rock-type associations is not valid. According to the age of the RIM rock assemblages, mélanges in the northern Gaspé Appalachians continued forming after the mid-Caradocian, later than the Dunnage Zone mélanges of southern Gaspé Appalachians. The juxtaposition and structural features of the RIM rock assemblages result from repeated faulting along the Shickshock Sud fault from Late Ordovician to Middle Devonian.
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Lansing, Sarah W. "A Range Extension for the Rock Vole, Microtus chrotorrhinus, in Labrador." Canadian Field-Naturalist 119, no. 3 (July 1, 2005): 412. http://dx.doi.org/10.22621/cfn.v119i3.153.
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Rock Voles (Microtus chrotorrhinus) were previously documented only from the southern coast of Labrador and the Strait of Belle Isle south of Hamilton Inlet. During two field seasons in 2000 and 2001, both in July, six Rock Vole specimens were collected on Southern Island, off the north-central coast of Labrador, extending the range of the subspecies Microtus chrotorrhinus ravus approximately 250 km to the central Labrador coast north of Hamilton Inlet. Rock Voles were trapped primarily in stunted Black Spruce (Picea mariana) forest and areas associated with rocks, thick brush, and water.
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Rasbury, E. Troy, and Jennifer M. Cole. "Directly Dating Sedimentary Rocks." Paleontological Society Papers 12 (October 2006): 77–105. http://dx.doi.org/10.1017/s1089332600001364.
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This contribution seeks to provide a summary of radiometric dating techniques that are currently applicable to Phanerozoic sedimentary deposits and therefore relevant to paleontologists. First we overview the assumptions necessary for radiometric dating and introduce isochrons and concordia diagrams as methods for calculating ages and evaluating isotope systematics. We then focus on the four most promising systems: U-Pb dating of carbonates, Re-Os dating of black shales, and U-Pb and Lu-Hf dating of phosphates. We review expected geochemical behavior of daughter and parent isotopes in the context of both marine and terrestrial depositional environments. A critical evaluation of previously published ages and potential directions for future work are provided.
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Vernik, Lev, and Amos Nur. "Ultrasonic velocity and anisotropy of hydrocarbon source rocks." GEOPHYSICS 57, no. 5 (May 1992): 727–35. http://dx.doi.org/10.1190/1.1443286.
Full textAbstract:
An experimental study of the physical properties of black, kerogen‐rich shales, also including maturation analysis, scanning electron microscope (SEM) observations, and physical modeling, revealed fairly peculiar petrophysical parameters. Specifically, these rocks have very low porosity and density, but most importantly, both P and S ultrasonic velocities normal to bedding are extremely low, whereas they are much higher parallel to bedding, giving rise to a strong anisotropy even at high confining pressures. We found that these parameters primarily reflect kerogen content, microstructure, and maturation level of these rocks. We found also that microcracks inferred from ultrasonic velocity measurements occur only in mature shales. These microcracks are parallel to the bedding plane and further enhance strong intrinsic anisotropy, notably at low effective pressure. Our results show, that on a small scale, kerogen‐rich shales are transversely isotropic rocks and can be effectively modeled using the thin‐layer composite concept modified to account for the specific distribution of organic matter in the rock fabric.
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Lasheen, El Saeed R., Mohammed A. Rashwan, Hamid Osman, Sultan Alamri, Mayeen U. Khandaker, and Mohamed Y. Hanfi. "Radiological Hazard Evaluation of Some Egyptian Magmatic Rocks Used as Ornamental Stone: Petrography and Natural Radioactivity." Materials 14, no. 23 (November 28, 2021): 7290. http://dx.doi.org/10.3390/ma14237290.
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Magmatic rocks represent one of the most significant rocks due to their abundance, durability and appearance; they can be used as ornamental stones in the construction of dwellings. The current study is concerned with the detailed petrography and natural radioactivity of seven magmatic rocks. All are commercial granitic rocks and are identified as black Aswan, Nero Aswan, white Halayeb, Karnak, Verdi, red Hurghada and red Aswan. Their respective mineralogical compositions are classified as porpheritic granodiorite, granodiorite, tonalite, monzogranite, syenogranite, monzogranite and syenogranite. A total of nineteen samples were prepared from these seven rock types in order to assess their suitability as ornamental stones. Concentrations of 226Ra, 232Th and 40K radionuclides were measured using NaI (Tl) scintillation gamma-ray spectrometry. Among the studied magmatic rocks, white Halayeb had the lowest average values of 226Ra (15.7 Bq/kg), 232Th (4.71 Bq/kg) and 40K (~292 Bq/kg), all below the UNSCEAR reported average world values or recommended reference limits. In contrast, the other granitic rocks have higher values than the recommended limit. Except for the absorbed dose rate, other radiological hazard parameters including radium equivalent activity, annual effective dose equivalent, external, and internal hazard indices reflect that the White Halyeb rocks are favorable for use as ornamental stone in the construction of luxurious and high-demand residential buildings.
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Mohammed, Israa Imad, and Hamid A. Alsultan. "Facies Analysis and Depositional Environments of the Nahr Umr Formation in Rumaila Oil Field, Southern Iraq." Iraqi Geological Journal 55, no. 2A (July 31, 2022): 79–92. http://dx.doi.org/10.46717/igj.55.2a.6ms-2022-07-22.
Full textAbstract:
The Nahr Umr Formation (Albian) was studied in the Rumaila oil field, southern Iraq. It consists of sandstone with high porosity and permeability, and contains a few shale overlaps that permeate the sandstone in the lower part of it, while it consists of shale and a few limestone rocks from the electrification in the upper part. The upper contact surface of this formation is conformable and graded with the Mauddud Formation. The limestone at the base of the Mauddud Formation may be on top of the black shale of the Nahr Umr Formation, and this formation is bounded from below by the Shuaiba Formation in an unconformable, which corresponds when the black shale of the Nahr Umr Formation sits on the limestone to form the Shuaiba Formation. The monocrystalline Quartz mineral is the major component of the Sandstone, with small percentages of polycrystalline quartz, feldspar, and rock fragments, according to the petrographical investigation. Mineral and textural maturity were present in the formation of rocks. Compaction, cementation, were the most important processes that influenced the rock characteristics of Nahr Umr's sandstone rocks. Six lithofacies shale, lenticular bedded sandstone–mudstone, false bedded sandstone–mudstone, siltstone–shale, cross-bedded sandstone, and parallel and cross-lamination sandstone were identified as representing the different sub environments within the different parts of transitional environments (fluvial and deltaic depositional environments), which represented oscillations in sea level rise and stillstands of the relative sea level controlled by tectonics as sediments of the basin transitioned from freshwater to marine conditions.
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Heflik, Wiesław, Lucyna Natkaniec-Nowak, Paweł P. Zagożdżon, Katarzyna D. Zagożdżon, Magdalena Dumańska-Słowik, and Janina Jarocka. "Mineralogical and Petrographical Characteristics of Hornfels from Kowary (The Lower Silesia)." Gospodarka Surowcami Mineralnymi 32, no. 2 (June 1, 2016): 45–62. http://dx.doi.org/10.1515/gospo-2016-0013.
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Abstract Hornfels from the closed “Wolność” mine (Kowary, the Lower Silesia) are recognized as thermally metamorphosed rocks belonging to hornblende-hornfels facies or locally a facies of pyroxene hornfels. Their texture reveal the traces of some deformations such as folding or fractures. Their protholit is described as a pelitic deposit enriched with clay minerals. The sediment was altered into meta-pelities-aleurites after the diagenesis, and later the rock was intensely thermally metamorphosed at the contact with the intrusion of the Karkonosze granitoid. Three varieties are distinguished based on their colour: green, grey and black. Green and black colours result from the predominance of hornblende and biotite over other rock components, respectively. Whereas grey hornfels are composed of similar amounts of both mafic minerals: biotite and hornblende. Quartz, mica minerals (biotite and muscovite), amphibole, (hornblende), acid plagioclase and andalusite, epidote group (clinozoisite), orthoclase and pyroxene make up hornfels components. Locally, andalusite is accompanied by sillimianite, which indicates a higher degree of contact metamorphism alterations. Three generations of minerals are distinguished in the rocks: allogenic (I), metamorphic (II) and hydrothermal (III). The allogenic phases are represented by heavy minerals such as zircon, apatite and monazite, which are characteristic of the protholit. The main components of the rocks (e.g. quartz, hornblende, feldspars, andalusite, sillimanite, mica minerals) belong to metamorphic minerals. Chalcopyrite, pyrite and fluorite are surely hydrothermally originated phases. Granitoides found at the contact zone with hornfels indicate traces of metasomatic alteration as a result of endomorphism in this region.
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Khan, Salman, Abdul Ghaffar, Inayat Ullah, Fida Murad, Jalil Ahmad, and Muhammad Ishaq Kakar. "A Case Study on Distribution of Gemstone in Bela Ophiolite, District Khuzdar, Balochistan." International Journal of Economic and Environmental Geology 12, no. 4 (January 14, 2022): 1–10. http://dx.doi.org/10.46660/ijeeg.vol12.iss4.2021.636.
Full textAbstract:
Bela Ophiolite and suture zone host several types of gemstones in the underlain and overlain rocks such as garnet (demantoid and almandine), quartz, brucite, malachite, chrysocolla, azurite, calcite, natrolite, green chert, jasper, serpentine, agate, epidote, augite and prehnite. However, the rare gemstones including demantoid garnet are found as dodecahedron green crystals associated with the altered peridotite rocks such as serpentinite. Brucite is found in the botryoidal habit in the ultramafic rocks of Bela Ophiolite associated with the chromite mines in the Baran Lak and Amorzai area of Wadh in the host rock dunite. The serpentine is found in several locations associated with the altered ultramafic rocks formed after the serpentinization of peridotite. Furthermore, one of the rare gemstones such as petroleum and diamond quartz is formed due to the hydrothermal intrusion in the sedimentary rocks such as limestone; calcite also occurs in limestone as dogtooth crystals. While azurite, malachite and chrysocolla are formed as secondary deposits in the oxidized zone of copper and sulphide mines in the Manjawi, Nal and Sonaro associated adjacent to basalt. Moreover, epidote is found as green crystals having porphyritic texture in the host rock granite mainly in the Bakhalo area, Wadh. Agate, jasper, green chert and several other kinds of chert are found associated with the basalt chert unit in the mélange and gossan. In addition to that natrolite is found in the Nal ophiolite mainly in the Hazarghanji town found associated with the cracks and vugs of dolerite dykes as fibrous and cylindrical crystals. In metamorphic sole rocks of Bela Ophiolite in the Sonaro area, marble and quartzite are associated with the metamorphic rocks such as greenschist and amphibolite facies that are formed during the e volution period of the ophiolite. In pegmatite gabbro, the elongated and prismatic black crystals of augite are found in the host rock gabbro near the Ornach cross area, and the prehnite gemstone is found associated with the basalt and gabbroic rocks transition zone in the Ornach area.
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McKinney, Frank K. "Determining Age of Rocks and Fossils." Paleontological Society Papers 2 (October 1996): 115–25. http://dx.doi.org/10.1017/s1089332600003193.
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The Age of fossils intrigues almost everyone. Students not only want to know how old a fossil is, but they want to know how that age was determined. Some very straightforward principles are used to determine the age of fossils. Students should be able to understand the principles and have that as a background so that age determinations by paleontologists and geologists don't seem like black magic.
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Caplette, Jaime N., Michael Schindler, and T. Kurtis Kyser. "The black rock coatings in Rouyn-Noranda, Québec: fingerprints of historical smelter emissions and the local ore." Canadian Journal of Earth Sciences 52, no. 11 (November 2015): 952–65. http://dx.doi.org/10.1139/cjes-2015-0064.
Full textAbstract:
Smelting of base metal sulfide rich ore in Rouyn-Noranda, Québec, has led to the formation of black rock coatings on exposed rocks to a maximum distance of 6 km from the smelter centre. This study has shown that these coatings are excellent mineralogical and chemical fingerprints of smelter emissions, ore types, and elemental partitioning into mineral phases. The black coatings are composed of a silica-rich matrix that formed due to the intense chemical weathering of exposed silicate rocks interacting with acidic meteoric waters. They contain metal sulfate rich layers along the atmosphere-coating interface (ACI) and rock-coating interface (RCI) formed by the in situ dissolution and precipitation of metal(loid)-bearing phases. Entombed within the silica matrix are spherical particulates and particles composed of Cu- and Zn-bearing Fe oxides (e.g., spinels), Fe oxides (e.g., hematite), Pb silicates (e.g., alamosite), sulfates (anglesite (PbSO4) and minerals of the jarosite group), amphiboles, pyroxenes, micas, Na feldspar, and clinochlore. Concentrations of elements are low in proximity to the smelter but drastically increase ∼2 km from the stack, most likely the result of a shadow effect of the smelter. This shadow effect is more pronounced if an element is highly compatible with minerals of the jarosite and spinel groups; it is called the smelter-compatibility effect. Elements displaying a high smelter-compatibility effect are Ag, Cu, Se, and As, whereas elements such as Hg, which is incompatible with the jarosite and spinel groups, show a low smelter-compatibility effect. High δ34S (5.5‰) values in proximity to the smelter and their decrease with distance is the result of mixing processes between primary and secondary sulfates in the atmosphere. The relative enrichments of metal(loid)s in coatings at Rouyn-Noranda and Sudbury, Ontario, when normalised to the MUd standard from Queensland, Australia, (MUQ) reflect the composition of the smelter emissions, ore, and lithologies. Black rock coatings of the Rouyn-Noranda and Sudbury study areas are enriched, for example, in Pb and Fe, respectively, reflecting higher abundances of galena and Fe-bearing minerals in the respective ore, emissions, and rocks in the region.
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Motoki, Akihisa, Giannis Hans Petrakis, Rodrigo Soares, Susanna Eleonora Sichel, and José Ribeiro Aires. "New method of semi-automatic modal analyses for phenocrysts of porphyritic rocks based on quantitative digital colour specification technique." Rem: Revista Escola de Minas 60, no. 1 (March 2007): 13–20. http://dx.doi.org/10.1590/s0370-44672007000100003.
Full textAbstract:
This paper proposes a new method for modal analyses of centimetric phenocrysts and porphyroblasts using a digital rock image. The dot matrix image of the rock is imported into vectorial draw software as background. The outline of all of the phenocrysts is marked on the overlay by closed vectorial curves and their internal area is painted in black. After this operation, the rock image on the background is deleted and the background is painted in white. The vectorial objects composed of the background and the overlay are exported as a matrix image of BMP format. The percentage of the areas painted in black corresponds to modal abundance of the phenocrysts, and it is calculated by the Wilber colour specification software. This method has high precision in graphic processing. However the translucency of the groundmass causes uncertainness in vectorial phenocryst marking. Therefore, it is recommended for rocks with phenocrysts larger than 5 mm.
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Tugarova, M. A. "Indicator signs of carbonate microbialites in black shale formations: isotopic composition and biomarkers." Vestnik of Geosciences 11 (2021): 55–61. http://dx.doi.org/10.19110/geov.2021.11.5.
Full textAbstract:
Carbonate rocks represented by nodules, lenses, layers of different morphology and length are typical for the black shale formations of different ages. They are of the greatest interest in oil source rocks as indicators of complex and not always unambiguously interpreted geological processes. A special place among these sedimentary bodies is occupied by microbialites, which indicate suppression of development of marine organic biocenoses, and often reflect emanation processes in ancient strata. Proof of these phenomena is fundamentally important for predicting and assessing the oil and gas potential of unconventional reservoirs. On the example of carbonate solids of Triassic and Jurassic black shale formations, we present a complex analytical method to determine the microbial biochemical genesis of rocks on the base of the isotopic composition of carbon and oxygen, together with the hydrocarbon molecular markers of organic matter. The geochemical features of the isolated microbialites suggest that they are resulted from a complex history of black shale formations, which reflects both background lithogenetic transformations and superimposed processes, including high-temperature hydrothermal ones.
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Bilanchyn, Yaroslav, Mykola Tortyk, Iryna Leonidova, and Andrii Buyanovskyy. "Soils of Zmiiny island – a mirror of his landscape ecological past, present and future." Visnyk of the Lviv University. Series Geography, no. 51 (December 27, 2017): 33–42. http://dx.doi.org/10.30970/vgg.2017.51.8735.
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Zmiiny island soils described as a function of a mirror of past, present and future of his landscape and ecological conditions and soil-forming processes. The article estimates the generalized scheme of soil-formation on the on dense acidic rocks of the island that includes gradually changing stages of weathering of rocks and formation of rubble-rocky crust of their weathering and local curuda formation - primitive soil formation - black soil formation under the steppe herbaceous vegetation on areas with a crust of weathering capacity of more than 10–12 cm. The soils profile here usually grows up as the biomass grows above-ground vegetation. There are two main scenarios of soil-forming and soils evolution have been proposed – optimistic with steep herbaceous vegetation preservation and further soil formation, and hazardous with herbaceous vegetation cover destroying. The strategy of measures to preserve the unique steppe landscape of the island with peculiar black soils recommends to prioritize tourist-recreational, health-improving and educational activities and systematic monitoring of the natural and ecological environment. Key words: Zmiiny island, soils and soil cover, landscapes, soils and soil-forming evolution.
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Petitte, J. N., M. E. Clark, G. Liu, A. M. Verrinder Gibbins, and R. J. Etches. "Production of somatic and germline chimeras in the chicken by transfer of early blastodermal cells." Development 108, no. 1 (January 1, 1990): 185–89. http://dx.doi.org/10.1242/dev.108.1.185.
Full textAbstract:
Cells were isolated from stage X embryos of a line of Barred Plymouth Rock chickens (that have black pigment in their feathers due to the recessive allele at the I locus) and injected into the subgerminal cavity of embryos from an inbred line of Dwarf White Leghorns (that have white feathers due to the dominant allele at the I locus). Of 53 Dwarf White Leghorn embryos that were injected with Barred Plymouth Rock blastodermal cells, 6 (11.3%) were phenotypically chimeric with respect to feather colour and one (a male) survived to hatching. The distribution of black feathers in the recipients was variable and not limited to a particular region although, in all but one case, the donor cell lineage was evident in the head. The male somatic chimera was mated to several Barred Plymouth Rock hens to determine the extent to which donor cells had been incorporated into his testes. Of 719 chicks hatched from these matings, 2 were phenotypically Barred Plymouth Rocks demonstrating that cells capable of incorporation into the germline had been transferred. Fingerprints of the blood and sperm DNA from the germline chimera indicated that both of these tissues were different from those of the inbred line of Dwarf White Leghorns. Bands that were present in fingerprints of blood DNA from the chimera and not present in those of the Dwarf White Leghorns were observed in those of the Barred Plymouth Rocks.(ABSTRACT TRUNCATED AT 250 WORDS)
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AGRELL, S. O., G. A. CHINNER, and P. D. ROWLEY. "The black skarns of Pine Canyon, Piute County, Utah." Geological Magazine 136, no. 4 (July 1999): 343–59. http://dx.doi.org/10.1017/s0016756899002800.
Full textAbstract:
A small micromonzonite pluton intruding Miocene extrusives of the Marysvale volcanic field of southern Utah has undergone a sequence of explosive brecciation, syenite veining, rheomorphism, calcium metasomatism and zeolitization. Skarn-like occurrences of magnetite and Al-spinel-rich feldspathoidal rocks within the outcrop are of two main types: (1) an olivine-bearing variety with occasional REE-rich minerals (zirconolite) occurs as veins and seams in desilicated latite screens and xeno-liths.; (2) an aluminous, corundum- and hibonite-bearing variety with accessory zirconolite, perovskite and armalcolite occurs mainly as fillings to the micromonzonite breccias. The chemically disparate types are interpreted as having initiated as propylitic, and argillic/alunitic, alterations of latite country rock in the early hydrothermal system of the pluton. Subsequent intrusion of the micromonzonite to higher levels has incorporated these products into the igneous complex, in which they have experienced varying degrees of nephelinization, pyrometamorphism, rheomorphism and veining.
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Waldron, John W. F., Rebecca A. Jamieson, Hayley D. Pothier, and Chris E. White. "Sedimentary and tectonic setting of a mass-transport slope deposit in the Halifax Group, Halifax Peninsula, Nova Scotia, Canada." Atlantic Geology 51, no. 1 (March 24, 2015): 084. http://dx.doi.org/10.4138/atlgeol.2015.004.
Full textAbstract:
<p align="LEFT">Fine-grained metasedimentary rocks of the Halifax Group in southern mainland Nova Scotia can be subdivided into mappable units. In Halifax Peninsula, sulphide-rich hornfels, black slate, metasiltstone, and metasandstone of the Cunard Formation are overlain by grey metasedimentary rocks with abundant cross-laminations and local carbonate and calc-silicate concretions, assigned to the Bluestone Quarry Formation. No fossils are known from the Bluestone Quarry Formation but lithological correlatives elsewhere are Tremadocian. The Bluestone Quarry Formation is here divided into four members. The lowest (Point Pleasant member) contains thin parallel-laminated and cross-laminated <span style="font-family: MinionPro-Regular; font-size: small;"><span style="font-family: MinionPro-Regular; font-size: small;">metasandstone beds with Bouma T</span></span><span style="font-family: MinionPro-Regular; font-size: xx-small;"><span style="font-family: MinionPro-Regular; font-size: xx-small;">bcde </span></span><span style="font-family: MinionPro-Regular; font-size: small;"><span style="font-family: MinionPro-Regular; font-size: small;">and T</span></span><span style="font-family: MinionPro-Regular; font-size: xx-small;"><span style="font-family: MinionPro-Regular; font-size: xx-small;">cde </span></span><span style="font-family: MinionPro-Regular; font-size: small;"><span style="font-family: MinionPro-Regular; font-size: small;">structures, and thicker beds with Bouma ‘a’ divisions. The Black Rock </span></span>Beach member lacks the thicker massive beds and is dominated by rippled and cross-laminated metasedimentary rocks. The overlying Chain Rock member, an erosion-resistant ridge-forming unit, is disrupted by folds and boudinage. Bedding is truncated at the upper contact, and the internal structures are overprinted by (and therefore predate) the Neoacadian cleavage. They are interpreted as products of synsedimentary mass transport. Scarce folds in the Chain Rock member and current ripples in the underlying unit are consistent with a N or NW transport direction. The overlying Quarry Pond member consists of thinly bedded coherent metasedimentary rocks that generally resemble those of the Black Rock Beach member. Although there are indications of upward shallowing in equivalent successions elsewhere in the Halifax Group, the presence of a major mass transport deposit in the Bluestone Quarry Formation shows that this part of the Halifax Group was deposited on a submarine paleoslope. The failure of geologists to identify this feature in much-visited outcrops testifies to the difficulty of identifying synsedimentary deformation features that have been overprinted by later tectonic deformation.</p>
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Nourafkan, E., Z. Hu, M. Garum, H. Esmaeili, and D. Wen. "Nanomaterials for subsurface application: study of particles retention in porous media." Applied Nanoscience 11, no. 6 (May 7, 2021): 1847–56. http://dx.doi.org/10.1007/s13204-021-01843-2.
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AbstractThe ability to transport nanoparticles through porous media has interesting engineering applications, notably in reservoir capacity exploration and soil remediation. A series of core-flooding experiments were conducted for quantitative analysis of functionalized TiO2 nanoparticles transport through various porous media including calcite, dolomite, silica, and limestone rocks. The adsorption of surfactants on the rock surface and nanoparticle retention in pore walls were evaluated by chemical oxygen demand (COD) and UV–Vis spectroscopy. By applying TiO2 nanoparticles, 49.3 and 68.0 wt.% of surfactant adsorption reduction were observed in pore walls of dolomite and silica rock, respectively. Not surprisingly, the value of nanoparticle deposition for dolomite and silica rocks was near zero, implying that surfactant adsorption is proportional to nanoparticle deposition. On the other hand, surfactant adsorption was increased for other types of rock in presence of nanoparticles. 5.5, 13.5, and 22.4 wt.% of nanoparticle deposition was estimated for calcite, black and red limestone, respectively. By making a connection between physicochemical rock properties and nanoparticle deposition rates, we concluded that the surface roughness of rock has a significant influence on mechanical trapping and deposition of nanoparticles in pore-throats.
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Williams, H., K. L. Currie, and M. A. J. Piasecki. "The Dog Bay Line: a major Silurian tectonic boundary in northeast Newfoundland." Canadian Journal of Earth Sciences 30, no. 12 (December 1, 1993): 2481–94. http://dx.doi.org/10.1139/e93-215.
Full textAbstract:
The Dog Bay Line separates different Silurian rock groups in northeast Newfoundland. West of the line, terrestrial volcanic rocks and sandstones (Botwood Group) overlie marine greywackes and conglomerates (Badger Group). East of the line, red sandstones overlie shallow marine shales and limestones (Indian Islands Group). Throughout Dog Bay, the line is marked by a disrupted zone of dark grey to black shales, volcanic rocks, and gabbros. Pervasive dextral, transpressive ductile deformation followed by successively more brittle extension with renewed dextral movements mark the northwest side of the line on the coast.The Dog Bay Line is traceable for 100 km and it is open-ended. Dextral offset is deduced to be many tens of kilometres. The line trends northeast, parallel to outcrop belts, and both the line and outcrop belts are curved eastward at the coast. The Mount Peyton Batholith, dated at 420 ± 8 Ma, apparently cuts the line.The Dog Bay Line occurs within the Dunnage Zone whose Cambrian–Ordovician rocks represent vestiges of the Iapetus Ocean. Northwest of the line, the Silurian rocks were deposited on Ordovician rocks already accreted to Laurentia. Southeast of the line, the Silurian rocks were deposited on Ordovician rocks already amalgamated with the continental Gander Zone. Timing of major movement and a Silurian marine to terrestrial depositional change recorded on both sides of the line agree within error with isotopic ages for the onset of plutonism, regional deformation, and metamorphism in central Newfoundland. The Dog Bay Line may mark the terminal Iapetus Ocean.
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Stober, I. "Hydrogeological investigations in crystalline rocks of the Black Forest, Germany." Terra Nova 8, no. 3 (May 1996): 255–58. http://dx.doi.org/10.1111/j.1365-3121.1996.tb00754.x.
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Mulyaningsih, Sri, Muchlis Muchlis, Nur W. A. A. T. Heriyadi, and Desi Kiswiranti. "Volcanism in The Pre-Semilir Formation at Giriloyo Region; Allegedly as Source of Kebo-Butak Formation in the Western Southern Mountains." Journal of Geoscience, Engineering, Environment, and Technology 4, no. 3 (September 30, 2019): 217. http://dx.doi.org/10.25299/jgeet.2019.4.3.2262.
Full textAbstract:
Kebo-Butak Formation was known to be the oldest volcanic rocks limited in regional terms in the lower Baturagung Hills, Gedangsari area, Gunungkidul Regency. The main constituents of the Kebo-Butak Formation consist of intersection of volcanic-clastic rocks and calcareous sediments, locally also found basalt lava with pillow structures; which distinguished it from other volcanic rock formations in the Southern Mountains. This study aims to determine the relationship of volcanic rocks exposed in Giriloyo with the Kebo-Butak Formation in the Baturagung Hills; the chronostratigraphy and the history of volcanic activities that produced the volcanic rocks of Giriloyo. This research was approached by volcanic geological mapping using surface mapping suported by gravity anayses. From the bottom to the top of the frontier areas result volcaniclastic rocks consisting of black tuffs with several fragments of volcanic bombs with basalt composition intersecting with thin basaltic lava inserted by calcareous claystone having an age of N5-7 (Early Miocene); pyroxene-rich basalt volcanic sequence consists of thick layers of tuff with creamy-brown color intersecting with lava and breccia inserted by calcareous sandstone aged N7-8; dikes, lava and agglomerates with basaltic composition and lava and agglomerates with andesitic composition. Stratigraphically, the volcanic rocks exposed at Giriloyo correlated with the volcanic rocks exposed at Karangtalun (Wukirsari) were under the Semilir Formation, bordered with normal fault N210oE/77o, the hanging wall composed by light grey tuff of Semilir Formation. Gravity analyses found high anomalies below the Semilir Formation exposed at Karangtalun-Munthuk (east of study area) continued to below the Giriloyo area. The high anomalies were identified as the igneous/ignimbrite volcanic sequence. Descriptively and stratigraphically, the Giriloyo volcanic sequence are a part of Kebo-Butak Formation. The petrogenesis of the volcanic rocks will be discussed in further research to interpret magmatological properties, the evolving paleo-volcano, and the absolute age of the rocks.
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Colomban, Philippe. "Rocks as blue, green and black pigments/dyes of glazed pottery and enamelled glass artefacts ? A review." European Journal of Mineralogy 25, no. 5 (January 16, 2014): 863–79. http://dx.doi.org/10.1127/0935-1221/2013/0025-2305.
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Costa, Marcondes Lima da, Dirse Clara Kern, Alice Helena Eleotério Pinto, and Jorge Raimundo da Trindade Souza. "The ceramic artifacts in archaeological black earth (terra preta) from Lower Amazon Region, Brazil: chemistry and geochemical evolution." Acta Amazonica 34, no. 3 (September 2004): 375–86. http://dx.doi.org/10.1590/s0044-59672004000300004.
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This paper carried out a chemical investigation of archaeological ceramic artifacts found in archaeological sites with Black Earth (ABE) in the Lower Amazon Region at Cachoeira-Porteira, State of Pará, Brazil. The ceramic artifacts, mostly of daily use, belong to Konduri culture (from 900 to 400 years BP). They are constituted of SiO2, Al2O3, Fe2O3, Na2O and P2O5; SiO2 and Al2O3 together add up to 80 % and indicate influence of acid rocks, transformed into clay minerals basically kaolinite. The relative high contents of P2O5 (2.37 % in average) come out as (Al,Fe)-phosphate, an uncommon fact in primitive red ceramics, but found in some roman and egyptian archaeological sites. The contents of the trace elements are similar or below the Earth's crust average. This chemical composition (except P2O5) detaches saprolite material derived acid igneous rocks or sedimentary ones as the main raw material of the ceramics. The contents of K, Na and Ca represent the feldspars and rock fragments possibly introduced into saprolitic groundmass, indicated by mineralogical studies. The presence of cauixi and cariapé as well as quartz sand was confirmed by optical microscope, SEM analyses and by the high silica contents of ceramic fragments. Phosphorus was possibly incorporated into groundmass during cooking of foods, and ABE soil profile formation developed on yellow Latosols. The raw materials and its tempers (cauixi, or cariapé, feldspar, crushed rocks, old ceramic artifacts and quartz fragments) are found close to the sites and therefore and certainly came from them.
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Klasner, J. S., and E. R. King. "Precambrian basement geology of North and South Dakota." Canadian Journal of Earth Sciences 23, no. 8 (August 1, 1986): 1083–102. http://dx.doi.org/10.1139/e86-109.
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Combined analysis of drill-hole, gravity, and magnetic data indicates that the buried Precambrian basement rocks of the Dakotas can be divided into several lithotectonic terranes. Eastern North Dakota and northeastern South Dakota are underlain by Archean gneiss. Except for the Black Hills region of South Dakota, where Archean rocks are also exposed, the western third of both Dakotas is underlain mainly by Early Proterozoic gneiss and metasedimentary rocks. Part of this region is underlain by Archean crust with an Early Proterozoic tectonic overprint. A broad transition zone of strongly overprinted Archean crust occurs between the Proterozoic rocks to the west and the Archean rocks to the east. South central South Dakota is underlain by an Early Proterozoic batholith. Early Proterozoic felsic volcanic rocks occur in southeast South Dakota. The bootheel portion of South Dakota contains a diverse assemblage of basement rocks that are partly Archean in age.Churchill Province rocks of the Trans-Hudson foldbelt project into the western Dakotas. The Thompson nickel belt and the Pickwitonei gneiss belt correlate with the western and eastern halves, respectively, of the transition between Archean and Proterozoic crust, and the Archean Glennie – Hanson Lake microcontinent of the Churchill Province likely extends into western North Dakota. Archean rocks of Minnesota extend into the eastern Dakotas, and the Wyoming craton extends to the Black Hills region. The Cheyenne foldbelt projects into southwest South Dakota. The Penokean foldbelt of Michigan and Wisconsin does not extend into the Dakotas, but it most likely extends into northwest Iowa.Tectonic evolution of the Early Proterozoic terrane in the Dakotas was most likely similar to plate tectonic models for the evolution of the Trans-Hudson foldbelt in the Churchill Province. As in the Churchill Province, the western Dakotas are underlain by Early Proterozoic rocks, but it is not known whether these rocks formed as a result of rifting and subsequent closure of a once extensive Archean crust or as a result of collision of once widely separated blocks of Archean crust.
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Kozlova, T. V., and E. A. Cherkez. "IDENTIFICATION OF WAVE DEFORMATION PROCESSES OF LANDSLIDES IN THE NORTHWESTERN BLACK SEA USING THE INSTRUMENTAL OBSERVATION DATA." Odesa National University Herald. Geography and Geology 26, no. 2(39) (March 25, 2022): 149–64. http://dx.doi.org/10.18524/2303-9914.2021.2(39).247157.
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Problem Statement and Purpose. At present, considering the conditions of slopes equilibrium, only the stresses caused by gravity, hydrodynamic and seismic effects are most often taken into account. As for tectonic stresses, their effect on landslide slopes has hardly been studied. At the same time, landslides and deformations ofslopes in a wide spatio-temporal range (with the frequency from several months to several dozens of years and the levels of massifs tectonic discreteness from first tensof meters to first kilometres) is also recorded in fact. Empirical data indicate that wave mechanism caused by rotational regime of the Earth can be one of the possible mechanisms explaining the high-frequency quasi-cyclic spatio-temporal variability of the rock mass stress-strain state. Purpose of the work has been to identify wave deformation processes in the Earth’s upper crust according to the data of instrumentalobservation of landslide slopes and relatively long line facilities deformation regime. In this work, we also intend to substantiate the thesis that wave exotectogenesis isone of the factors reducing the overall stability of landslide slopes. Data&Methods. The data of instrumental observations of structural components deformation in the underground drainage facilities of the landslide prevention works on Odesa coast that have accumulated during 50 years of operation, as well as the results of geodetic monitoring of landslide slope and the crest of plateau on the right bank of the Malyi Adzhalyk Liman within the territory of the Port Plant (ammonium plant) in 2000–2019 have been used to study the dynamics of deformation wave processes in the Earth’s upper crust. Statistical and cartographic analyses of the data sets mentioned above were carried out according to traditional methods using the Statistica, Matlab and Surfer software packages. Results. It has been found that modern dynamics of landslide slopes is significantly influenced by the periodic change of the stress-strainstate of rocks in space and time. The authors interpret the empirically revealed alternating in space zones of compression and extension, which cause the dynamics of vertical and horizontal reference benchmarks displacements in the inter-annual regime of marks displacement on the right bank of the Malyi Adzhalyk Liman and in the tunnels of Odesa coast as thereflection of wave geodynamics with periodic change of the stress-strainstate of rocks in space and time. Hierarchical layering of the tectonosphere in depth (the presence of layers with different elastic properties), tectonic discreteness and blockiness of rock massifs determine the spatial framework of the dynamically complex structure of the deformation field. Multiple cycles of compression-extensionof rocks lead to decrease in the rocks strength, accumulation of plastic deformations and activation of landslide displacements even on the coastal areas where anti-landslide measures have been implemented. To prepare design models correctly, it is important to take into account both the landslide formation mechanism and the factors that reduce the overall stability of the slope. The latter include the quasiperiodic variability of the rock mass stress-strain state controlled by rotational dynamics via wave mechanism.
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Mulyanto, Djoko, S. Subroto P.S., and Herwin Lukito. "Genesis Pedon Tanah yang Berkembang di Atas Batuan Karbonat Wonosari Gunungkidul." Forum Geografi 25, no. 2 (December 20, 2011): 100. http://dx.doi.org/10.23917/forgeo.v25i2.5038.
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The variation of soil color that developed on carbonate rocks which are generally white, very interesting to be studied. The aim of the study is to examine the formation of two pedons of black soil and red soil by hue 10 YR and hue 5 to 2.5 YR which successively developed on marly limestones and calcarenite. Analysis of mineral properties consist of the total minerals of sand fraction, clay fraction and rock powders. Soil chemical properties include: pH, organic C, exchangeable cations and cation exchange capacity, CaCO3, the amorphous-crystalline of Fe and Mn, the total of Fe and Mn, the analysis of physical properties is the texture of seven fractions. The results showed that the development of the red soil is much more developed than black soil that shown by intensively decalcification process of red soil that impact on the low of pH, base saturation and cation exchange capacity, whereas the development of black soil is inhibited. The formation of black soil is more inherited of clay bearing marly limestone after carbonate dissolution, whereas the red soil development through rubification and illuviation.
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Selbmann, Laura, Gerardo A. Stoppiello, Silvano Onofri, Jason E. Stajich, and Claudia Coleine. "Culture-Dependent and Amplicon Sequencing Approaches Reveal Diversity and Distribution of Black Fungi in Antarctic Cryptoendolithic Communities." Journal of Fungi 7, no. 3 (March 16, 2021): 213. http://dx.doi.org/10.3390/jof7030213.
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In the harshest environmental conditions of the Antarctic desert, normally incompatible with active life, microbes are adapted to exploit the cryptoendolithic habitat (i.e., pore spaces of rocks) and represent the predominant life-forms. In the rocky niche, microbes take advantage of the thermal buffering, physical stability, protection against UV radiation, excessive solar radiation, and water retention—of paramount importance in one of the driest environments on Earth. In this work, high-throughput sequencing and culture-dependent approaches have been combined, for the first time, to untangle the diversity and distribution of black fungi in the Antarctic cryptoendolithic microbial communities, hosting some of the most extreme-tolerant microorganisms. Rock samples were collected in a vast area, along an altitudinal gradient and opposite sun exposure—known to influence microbial diversity—with the aim to compare and integrate results gained with the two approaches. Among black fungi, Friedmanniomyces endolithicus was confirmed as the most abundant taxon. Despite the much stronger power of the high-throughput sequencing, several species were not retrieved with DNA sequencing and were detectable by cultivation only. We conclude that both culture-dependent and -independent analyses are needed for a complete overview of black fungi diversity. The reason why some species remain undetectable with molecular methods are speculated upon. The effect of environmental parameters such as sun exposure on relative abundance was clearer if based on the wider biodiversity detected with the molecular approach.
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Svetova, Evgeniya N., Svetlana Y. Chazhengina, Alexandra V. Stepanova, and Sergei A. Svetov. "Black Agates from Paleoproterozoic Pillow Lavas (Onega Basin, Karelian Craton, NW Russia): Mineralogy and Proposed Origin." Minerals 11, no. 9 (August 25, 2021): 918. http://dx.doi.org/10.3390/min11090918.
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The present study provides the first detailed investigation of black agates occurring in volcanic rocks of the Zaonega Formation within the Onega Basin (Karelian Craton, Fennoscandian Shield). Three characteristic texture types of black agates were identified: monocentric concentrically zoning agates, polycentric spherulitic agates, and moss agates. The silica matrix of black agates is only composed of length-fast and zebraic chalcedony, micro- and macro-crystalline quartz, and quartzine. In addition to silica minerals, calcite, chlorite, feldspar, sulphides, and carbonaceous matter were also recognised. The black colour of agates is related to the presence of disseminated carbonaceous matter (CM) with a bulk content of less than 1 wt.%. Raman spectroscopy revealed that CM from black agates might be attributed to poorly ordered CM. The metamorphic temperature for CM from moss and spherulitic agates was determined to be close to 330 °C, whereas CM from concentrically zoning agates is characterised by a lower temperature, 264 °C. The potential source of CM in moss and spherulitic agates is associated with the hydrothermal fluids enriched in CM incorporated from underlaying carbon-bearing shungite rocks. The concentrically zoning agates contained heterogeneous CM originated both from the inter-pillow matrix and/or hydrothermal fluids.
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Vernik, Lev. "Hydrocarbon‐generation‐induced microcracking of source rocks." GEOPHYSICS 59, no. 4 (April 1994): 555–63. http://dx.doi.org/10.1190/1.1443616.
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Laboratory measurements of ultrasonic velocity and anisotropy in kerogen‐rich black shales of varying maturity suggest that extensive, bedding‐parallel microcracks exist in situ in most mature source rocks undergoing the major stage of hydrocarbon generation and migration. Given the normal faulting regime with the vertical stress being the maximum principal stress typical of most sedimentary basins, this microcrack alignment cannot be accounted for using simplified fracture mechanics concepts. This subhorizontal microcrack alignment is consistent with (1) a model of local principal stress rotation and deviatoric stress reduction within an overpressured formation undergoing hydrocarbon generation, and with (2) a strong mechanical strength anisotropy of kerogen‐rich shales caused by bedding‐parallel alignment of kerogen microlayers. Microcracks originate within kerogen or at kerogen‐illite interfaces when pore pressure exceeds the bedding‐normal total stress by only a few MPa due to the extremely low‐fracture toughness of organic matter. P‐wave and, especially, S‐wave anisotropy of the most mature black shales, measured as a function of confining pressure, indicate the effective closure pressure of these microcracks in the range from 10 to 25 MPa. Estimates of pore pressure cycles in the matrix of the active hydrocarbon‐generating/expelling part of the source rock formation show that microcracks can be maintained open over the sequence of these cycles and hence be detectable via high‐resolution in‐situ sonic/seismic studies.