Characteristics of the Nanoscale Pore Structure in Northwestern Hunan Shale Gas Reservoirs Using Field Emission Scanning Electron Microscopy, High-Pressure Mercury Intrusion, and Gas Adsorption

2014 ◽  
Vol 28 (2) ◽  
pp. 945-955 ◽  
Author(s):  
Yang Wang ◽  
Yanming Zhu ◽  
Shangbin Chen ◽  
Wu Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Pressure ◽  
Pore Structure ◽  
Field Emission ◽  
Shale Gas ◽  
Gas Adsorption ◽  
Gas Reservoirs ◽  
Mercury Intrusion ◽  
Scanning Electron

Characteristics of Micro/Nanopores and Their Petroleum Significance in the Eastern Segment of the Altun Piedmont, Qaidam Basin, Western China

2021 ◽  
Vol 21 (1) ◽  
pp. 181-194
Author(s):  
Qing-Bin Xie ◽  
Xin Li ◽  
Chuan-Long Li ◽  
Yong-Shu Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Pressure ◽  
Field Emission ◽  
Qaidam Basin ◽  
Western China ◽  
Tight Sandstone ◽  
Eastern Segment ◽  
Scanning Electron ◽  
Nuclear Magnetic

With continuous improvements in nanotechnology, the development of micro/nanoscale pores and fractures in reservoirs can be more clearly identified, and great progress has been made in tight sandstone and shale. Bedrock has an ultralow porosity and is a reservoir with low permeability. To study the characteristics of micro/nanoscale pore development and reveal their petroleum significance in the eastern segment of the Altun Piedmont, research has been conducted with the use of cathodoluminescence, field emission scanning electron microscopy and energy spectrum analysis, formation microresistivity image logging, high-pressure mercury injection and nuclear magnetic logging. The results have shown that the porosity of the bedrock reservoir in the eastern segment of the Altun Piedmont, as measured by helium injection and nuclear magnetic logging, is between 0.004% and 9.76%, the average porosity is between 1.663% and 3.844%, and the permeability is between the maximum of 0.002 mD and 33.239 mD. The average permeability is between 0.02 mD and approximately 3.836 mD. Micro/nanopores are generally developed, with the majority being intragranular micro/nanopores, intercrystalline micro/nanopores and microcracks, as summarized by the field emission scanning electron microscopy and energy dispersive spectroscopy analysis. Four differently sized pores develop: micropores account for approximately 20%, transition pores account for approximately 30%, and mesopores and macropores account for approximately 25% each. The pore throat development below 100 nm is greater than 50% according to the collation of experimental data from high-pressure mercury intrusion; therefore, micro/nanopores are the main storage space in the study area, and the gas logging shows good results. Micro/nanopores are also one of the main reservoir spaces of bedrock reservoirs in conjunction with the conventional reservoir space, and thus, micro/nanopores have important petroleum significance.

Pore structure characterization of different rank coals using gas adsorption and scanning electron microscopy

Fuel ◽  
2015 ◽  
Vol 158 ◽  
pp. 908-917 ◽  
Author(s):  
Baisheng Nie ◽  
Xianfeng Liu ◽  
Longlong Yang ◽  
Junqing Meng ◽  
Xiangchun Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pore Structure ◽  
Gas Adsorption ◽  
Structure Characterization ◽  
Scanning Electron

Pore structure characterization of North American shale gas reservoirs using USANS/SANS, gas adsorption, and mercury intrusion

Fuel ◽  
2013 ◽  
Vol 103 ◽  
pp. 606-616 ◽  
Author(s):  
C.R. Clarkson ◽  
N. Solano ◽  
R.M. Bustin ◽  
A.M.M. Bustin ◽  
G.R.L. Chalmers ◽  
...  
Keyword(s):  
Pore Structure ◽  
Shale Gas ◽  
North American ◽  
Gas Adsorption ◽  
Structure Characterization ◽  
Gas Reservoirs ◽  
Mercury Intrusion ◽  
Shale Gas Reservoirs

Effect of laminae development on pore structure in the lower third member of the Shahejie Shale, Zhanhua Sag, Eastern China

2020 ◽  
Vol 8 (1) ◽  
pp. T103-T114
Author(s):  
Tingwei Li ◽  
Zhenxue Jiang ◽  
Pibo Su ◽  
Xi Zhang ◽  
Weitao Chen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pore Structure ◽  
Gas Adsorption ◽  
Eastern China ◽  
Spontaneous Imbibition ◽  
Reservoir Property ◽  
Shale Reservoirs ◽  
Interconnected Pores ◽  
Scanning Electron

Similar to mineral composition and organic geochemical features, laminae development significantly influences pore structure. Taking the lower third member of the Shahejie Shale (Es3l), Zhanhua Sag, Eastern China as the research object, we introduced various methods to analyze the influence of laminae development on pore structure, including thin section observations, field emission scanning electron microscopy, gas adsorption, high-pressure mercury injection, nano-computed tomography (CT), quantitative evaluation of minerals by scanning electron microscopy, and spontaneous imbibition. We draw the conclusions that various minerals present a mixed distribution in nonlaminated shale, whereas laminated shale is characterized by alternating bright and dark laminae. Dark laminae comprise clay and quartz, whereas bright laminae consist of calcite. Microfractures are abundant at the edges of the bright and dark laminae. Nonlaminated shale possesses a pore volume (PV) of [Formula: see text] and a specific surface area (SSA) of [Formula: see text]. In contrast, laminated shale has a PV of [Formula: see text] and an SSA of [Formula: see text] with good reservoir property. Pores, especially macropores and micropores, are much more developed in laminated shale than in nonlaminated shale. Interconnected pores in sheet form are extremely developed in laminated shale, whereas most of the interconnected pores in nonlaminated shale are distributed in isolated spherical and tubular forms. Because of the abundant interconnected pores and throats, laminated shale presents good connectivity. The slopes of the spontaneous imbibition curves in the first and second stages for laminated shale are greater than those for nonlaminated shale. Laminae development could provide microfractures as dominant pathways for fluid migration as well as promote the interconnection of pores, greatly increasing the connectivity of shale reservoirs.

Microstructure and Pore Systems Development of Ternary Gypsum-Based Mortars

2018 ◽  
Vol 760 ◽  
pp. 67-72
Author(s):  
Magdaléna Doleželová ◽  
Jitka Krejsová ◽  
Lenka Scheinherrová ◽  
Petr Svora ◽  
Alena Vimmrová
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pore Structure ◽  
Silica Fume ◽  
Mercury Intrusion Porosimetry ◽  
Hydrated Lime ◽  
Systems Development ◽  
Elementary Composition ◽  
Mercury Intrusion ◽  
Scanning Electron

Paper deals with ternary gypsum-based mortars with higher resistance against water, prepared from gypsum, hydrated lime, several pozzolans (crushed ceramic, silica fume, granulated blast slag) and sand. The samples were stored in the water and the pore systems development in time was studied by mercury intrusion porosimetry. The change of pore structure in samples with pozzolans were observed, the size of pores shifted to the smaller pores during tested period. The elementary composition and microstructure of all materials were also studied by scanning electron microscopy (SEM).

A New Image Processing Technique for STEM

1974 ◽  
Vol 32 ◽  
pp. 432-433
Author(s):  
Yasushi Kokubo ◽  
Hirotami Koike ◽  
Teruo Someya
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Scanning Electron Microscopy ◽  
Elastic Scattering ◽  
Field Emission ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Energy Analyzer ◽  
Scanning Microscope ◽  
Scanning Electron

One of the advantages of scanning electron microscopy is the capability for processing the image contrast, i.e., the image processing technique. Crewe et al were the first to apply this technique to a field emission scanning microscope and show images of individual atoms. They obtained a contrast which depended exclusively on the atomic numbers of specimen elements (Zcontrast), by displaying the images treated with the intensity ratio of elastically scattered to inelastically scattered electrons. The elastic scattering electrons were extracted by a solid detector and inelastic scattering electrons by an energy analyzer. We noted, however, that there is a possibility of the same contrast being obtained only by using an annular-type solid detector consisting of multiple concentric detector elements.

Scattering of Electrons at High - Pressure and Restoration of Image Contrast in High Pressure Scanning Electron Microscopy

1990 ◽  
Vol 48 (1) ◽  
pp. 384-385
Author(s):  
J. S. Shah ◽  
R. Durkin ◽  
A. N. Farley
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Pressure ◽  
Cross Sections ◽  
Single Scattering ◽  
Image Contrast ◽  
Experimental Scheme ◽  
Medium Resolution ◽  
Scattering Approximation ◽  
Scanning Electron

It is now possible to perform High Pressure Scanning Electron Microscopy (HPSEM) in the range 10 to 2000 Pa. Here the effect of scattering on resolution has been evaluated by calculating the profile of the beam in high pressure and assessing its effect on the image contrast . An experimental scheme is presented to show that the effect of the primary beam ionization is to reduce image contrast but this effect can be eliminated by a novel use of specimen current detection in the presence of an electric field. The mechanism of image enhancement is discussed in terms of collection of additional carriers generated by the emissive components.High Pressure SEM (HPSEM) instrumentation is establishing itself as commercially viable. There are now a number of manufacturers, such as JEOL, ABT, ESCAN, DEBEN RESEARCH, selling microscopes and accessories for HPSEM. This is because high pressure techniques have begun to yield high quality micrographs at medium resolution.To study the effect of scattering on the incident electron beam, its profile - in a high pressure environment - was evaluated by calculating the elastic and inelastic scattering cross sections for nitrogen in the energy range 5-25 keV. To assess the effect of the scattered beam on the image contrast, the modification of a sharp step contrast function due to scattering was calculated by single scattering approximation and experimentally confirmed for a 20kV accelerated beam.

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