Showing papers in "International Journal of Coal Geology in 2016"

TL;DR: In this article, a review of organic petrography applications in the North American shale plays through discussion of incident light photographic examples is presented. But, the work is limited to the use of high-resolution imaging techniques and in situ geochemical probing.

TL;DR: In this article, the authors used the smoothness of a normalized REY distribution pattern for testing the quality of REY chemical analyses for coal and other sedimentary rocks, including terrigenous source rocks, ingress of hydrothermal fluids, influence of marine environments, percolating natural waters, volcanic ashes, and sedimentary environments of peat formation.

TL;DR: In this paper, a review of the methods that may be used to evaluate the percentage of mineral matter for a coal sample, as opposed to the ash yield, and to identify the minerals, their individual percentages, and their modes of occurrence within the coal.

TL;DR: In this article, a unified model is established to describe gas-water-clay interactions, in which, gas-solid Langmuir equation and gas-liquid Gibbs equation are integrated by water coverage coefficient, and a mathematical model is presented to quantify thickness of water films by considering surface force interactions between liquid film and clay.

TL;DR: In this paper, a series of methane adsorption isotherms were measured at 35.4°C, 50.6°C and 65.4°C at pressures up to 15.74%.

TL;DR: In this paper, structural information of two coals from the Manisa Soma region, two from the Mugla Yatagan region and one from Kutahya Seyitomer region was reported.

TL;DR: In this paper, the pore structure characteristics of Lower Silurian Longmaxi shales from southern Sichuan Basin were investigated using a combination of field emission scanning electron microscope (FE-SEM) and argon ion beam milling.

TL;DR: In this article, a unique contrast agent technique using X-ray micro-computed tomography (micro-CT) was developed for studying micrometer-sized features in coal, which allows for the visualization of coal fractures not visible with conventional imaging methods.

TL;DR: Li et al. as mentioned in this paper focused on 21 core samples of Niutitang Shale from Well Yuke #1 in the southeast of Chongqing, to better understand their vertical reservoir characteristics and pore evolution.

TL;DR: In this paper, the geochemical and mineralogical compositions of the Late Permian No. 25 coal (semi-anthracite) and its host rocks (roof and floor strata) from the Guxu (Gulin-Xuyong) Coalfield, Sichuan Province, China were reported.

TL;DR: In this paper, four eastern Kentucky Pennsylvanian coals (from oldest to youngest, the Manchester, Pond Creek, Fire Clay, and Hazard coals) were examined for their total rare earth element (REY) concentration and the possible mechanisms for enrichment of the rare earths.

TL;DR: In this paper, geochemical data for Ordovician Wufeng Formation and Silurian Longmaxi Formation black shale deposition in the Sichuan Basin are presented and applied as proxies for deciphering paleoenvironment (detrital influx, redox conditions, paleoproductivity) and providing insight to paleoenvironmentsal conditions responsible for organic carbon accumulation.

TL;DR: In this article, Li et al. reported that although the tight sandstones have a certain hydrocarbon generation potential, mudstones are evidently higher quality source rocks and the silt-fine sandstones' reservoir quality is best among the three rock types.

TL;DR: In this article, a focused ion beam-scanning electron microscope (FIB-SEM) technique was employed to describe the optical characteristics and micro-nanopores of the graptolites of the Wufeng-Longmaxi Formations (Ordovician-Silurian) to determine the contribution of the Graptolite and to evaluate the thermal maturity.

TL;DR: In this article, the authors investigated how coal microstructure is related to changes in effective stress and how these parameters are interrelated, and found that when effective stress increased, the cleats became narrow and closed or disconnected.

TL;DR: Li et al. as mentioned in this paper examined nine Sinian-Cambrian shale samples from South China using ion-milling, FE-SEM, nitrogen adsorption and mercury intrusion.

TL;DR: In this paper, a 2D microstructural characterization of porosity and in particular organic-matter porosity of two organic-rich Posidonia Shale samples with different maturity using Broad Ion Beam milling and Scanning Electron Microscopy (BIB-SEM) was presented.

TL;DR: In this paper, an exploratory study on improving coal porosity and permeability by microwave treatment was proposed, and the pore size distribution of four unconstrained coals (lignite, subbituminous, bituminous and anthracite) before and after microwave treatment, were evaluated using the nuclear magnetic resonance.

TL;DR: In this article, the authors investigated the characteristics of coal macrolithotypes across multiple length scales using optical microscopy and X-ray computed tomography (CT) and found that the bright coal has the highest gas adsorption capacity, due to the largest smaller micropores.

TL;DR: In this article, the effect of polishing on the Raman spectra of vitrinites is not significant up to maximum reflectance values of ~ 7% and a linear and robust maturity index is established.

TL;DR: In this paper, the Fourier transform infrared (FTIR) spectroscopy equipped with in-situ reactor cell was introduced to investigate the change in the methyl and methylene groups of different classes of coals (lignite, sub-bituminous and bituminous) during their low-temperature oxidation at temperatures below 230°C.

TL;DR: In this article, two new RSCM parameters, termed Raman Area Ratio (RAR) and Scaled Total Area (STA), are introduced, which are tested on a sample suite of organic rich shales and slates of the Teuschnitz Syncline (Thuringia, Germany) of well constrained very low to low metamorphic grade, defined by illite crystallinty and vitrinite reflectance.

TL;DR: In this article, a review summarises the current knowledge regarding biogenic CH4 in SG and CBM: from the nature of the rocks to the producing microbial community and the indicators of biogenicCH4, illustrating how these two environments show remarkably similar opportunities for the stimulation of BCH4 generation.

TL;DR: In this paper, the authors study the lower third Member (Es3L) of the Eocene Shahejie Formation in the Zhanhua Depression, Bohai Bay Basin, eastern China to understand how paleoclimate influenced depositional processes and organic matter accumulation of lacustrine organic-rich mudstone.

TL;DR: Mudrocks and shales contain pores within the size range of 2-100nm as discussed by the authors. Flow of supercritical gas in these pores at reservoir pressure-temperature conditions falls within the slip-flow and early transition-flow regime (0.001).

TL;DR: Wang et al. as discussed by the authors used the UDEC-Voronoi method to investigate the process of progressive roof failure in a wide coal roadway from water-rich roofs, where the studied domain was partitioned into polygonal blocks bonded through contacts with pre-defined dimensions.

TL;DR: In this article, the authors apply an integrated analytical program to carbonate-dominated mudrocks from the Lucaogou Formation in Santanghu Basin to document the nature of organic matter (OM) in the context of an evolving lake system.

TL;DR: In this paper, the authors developed a simple extension of the Terzaghi effective stress model to include the independent effects of pore and confining pressures and the sorption strain, which was tested by applying it to a data base of laboratory measurements of coal core permeability with helium, nitrogen, methane, and carbon dioxide over a range of Pore and Confining pressures where it was shown to accurately match the observations with generally consistent model properties.

TL;DR: In this paper, a fully coupled mathematical model was developed by incorporating coal permeability with coal mechanical properties and gas adsorption/desorption and was then implemented into a Finite Element software.

TL;DR: In this article, the authors measured the permeability of shale under anisotropic true triaxial stress conditions using a newly developed True Triaxial Geophysical apparatus and established a permeability model based on a consideration of shale anisotropy.