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.

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

Probing pore structure of virus filters using scanning electron microscopy with gold nanoparticles

2018 ◽  
Vol 552 ◽  
pp. 144-152 ◽  
Author(s):  
Hadi Nazem-Bokaee ◽  
Fatemeh Fallahianbijan ◽  
Dayue Chen ◽  
Sean Michael O'Donnell ◽  
Christina Carbrello ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Gold Nanoparticles ◽  
Pore Structure ◽  
Scanning Electron

scholarly journals Experimental investigation of the effects of different types of fracturing fluids on the pore structure characteristics of Shale Reservoir Rocks

2019 ◽  
Vol 38 (3) ◽  
pp. 682-702 ◽  
Author(s):  
Zepeng Sun ◽  
Yue Ni ◽  
Yongli Wang ◽  
Zhifu Wei ◽  
Baoxiang Wu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pore Structure ◽  
Reservoir Rocks ◽  
Fracturing Fluids ◽  
Different Types ◽  
Shale Reservoir ◽  
Mineral Compositions ◽  
Over Time ◽  
Scanning Electron

The chemical and physical capabilities of shale can be altered by the interactions between fracturing fluid and shale formation, affecting the long-term reservoir productivity. To obtain information regarding how fracturing fluids with different components impact the pore structure, porosity and mineral compositions of shale reservoir rocks over time, two different types of commercial fracturing fluids (slick water and crosslinked gel) were used to react with the shales from Longmaxi Formation of Lower Silurian in the Sichuan Basin of South China. Experiments were conducted with various time intervals (1, 4 and 10 days) in a reactor at 50 MPa and 100°C, and then analytical methods including X-ray diffraction, low pressure nitrogen adsorption, field emission scanning electron microscopy and porosity measurement were used to examine the changes of mineralogical compositions, pore structure and porosity. The results demonstrated that the mineral compositions of shale samples were significantly changed after treatment with two different fracturing fluids for 4 days. The analysis of field emission scanning electron microscopy revealed that the carbonate minerals were dissolved and developed many dissolution pores after slick water treatment, while the crosslinked gel mainly caused the precipitation of carbonate minerals. After exposure to different fracturing fluids, the total pore volume and specific surface area decreased over time. Moreover, the fractal dimensions (D1 and D2) of shale showed an apparent decrease trend after treatment with two different fracturing fluids, indicating that the pore surface and structure become smooth and regular. The porosity of shale significantly decreased by 15.9% and 17.8%, respectively, after 10 days of slick water and crosslinked gel treatment. These results indicated that the injection of the two different types of fracturing fluids may negatively impact the shale gas production through reducing the nanopore structure and porosity of shale reservoir rocks.

Effect of sedimentary environment on shale lithofacies in the lower third member of the Shahejie Formation, Zhanhua Sag, eastern China

2017 ◽  
Vol 5 (4) ◽  
pp. T487-T501 ◽  
Author(s):  
Tingwei Li ◽  
Zhenxue Jiang ◽  
Chenlu Xu ◽  
Yuan Yuan ◽  
Pengfei Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Early Stage ◽  
Eastern China ◽  
Sedimentary Environment ◽  
Gas Production ◽  
Bohai Bay ◽  
Calcareous Shale ◽  
Shahejie Formation ◽  
Scanning Electron

Research on shale lithofacies is important for shale oil and gas production. This study focused on the lower third member of the Shahejie Formation ([Formula: see text]) in the Luo-69 well in the Zhanhua Sag, Jiyang Depression, Bohai Bay Basin, eastern China. Several methods, including thin section observations, total organic carbon (TOC) analysis, X-ray diffraction analysis, quantitative evaluations of minerals by scanning electron microscopy, major and trace-element analyses, and field emission-scanning electron microscopy, are used to investigate the effect of sedimentary environment on the type and distribution of shale lithofacies. Our research indicates that 36 types of shale lithofacies can be classified based on the TOC content, mineral composition, and sedimentary structure, of which five types are identified in the study area. The [Formula: see text] shale has a high calcareous mineral content (average of 49.64%), low clay and siliceous minerals contents (averages of 19.54% and 19.02%, respectively), a high TOC content (average of 3.00 wt%), and well-developed horizontal bedding. The sedimentary environment during the deposition of the [Formula: see text] shale in the Zhanhua Sag had a warm and moist climate, limited provenance, saline water, and strong reducibility. The sedimentary environment in the early stage had a drier climate, more limited provenance, higher salinity, and stronger reducibility than that in the later stage. Shale lithofacies can reflect a certain sedimentary environment and depositional process; similarly, a depositional environment controls the type and distribution of shale lithofacies. Due to the characteristics of the [Formula: see text] sedimentary environment, organic-rich massive mixed shale, organic-rich bedded mixed-calcareous shale, organic-rich laminated calcareous shale, and organic-fair laminated calcareous shale are developed in the [Formula: see text] formation from top to bottom.

Pore Structure and Microstructure of Foam Concrete

2010 ◽  
Vol 177 ◽  
pp. 530-532 ◽  
Author(s):  
Xin Gang Yu ◽  
Shi Song Luo ◽  
Yan Na Gao ◽  
Hong Fei Wang ◽  
Yue Xiang Li ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Image Analysis ◽  
Light Microscopy ◽  
Pore Structure ◽  
Digital Image ◽  
Digital Image Analysis ◽  
Foam Concrete ◽  
Structure And Microstructure ◽  
Scanning Electron

The pore structure and microstructure of the foam concrete was analyzed by scanning electron microscopy and light microscopy combined with digital image analysis. The results show that: (1) even-distributed fine and close pores resulting in high strength and low permeability; (2) uneven-distributed large size pores and open pores lead to low strength and high permeability; (3) light microscopy combined with digital image analysis is a cheap and convenient tool fitting for the pore structure analysis of the foam concrete; (4) scanning electron microscopy is very appropriate for the pore structure and microstructure analysis of the foam concrete.

scholarly journals Porosity in Polysilsesquioxane Xerogels

1999 ◽  
Vol 576 ◽  
Author(s):  
Brigitta M. Baugher ◽  
Duane A. Schneider ◽  
Douglas A. Loy ◽  
Kamyar Rahimian
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Pore Structure ◽  
Convenient Method ◽  
Sol Gel ◽  
Monomer Concentration ◽  
Inorganic Materials ◽  
Sol Gel Process ◽  
Very High ◽  
Scanning Electron

ABSTRACTPolymerization of organotrialkoxysilanes is a convenient method for introducing organic functionality into hybrid organic-inorganic materials. However, not much is known about the effects of the organic substituent on the porosity of the resulting xerogels. In this study, we prepared a series of polysilsesquioxane xerogels from organotrialkoxysilanes, RSi(OR′)3, with different organic groups (R = H, Me, Et, dodecyl, hexadecyl, octadecyl, vinyl, chloromethyl, cyanoethyl). Polymerizations of the monomers were carried out under a variety of conditions, varying monomer concentration, type of catalyst, and alkoxide substituent. The effect of the organic substituent on the sol-gel process was often dramatic. In many cases, gels were formed only at very high monomer concentration and/or with only one type of catalyst. All of the gels were processed as xerogels and characterized by scanning electron microscopy and nitrogen sorption porosimetry to evaluate their pore structure.

scholarly journals Microstructure and microwave absorbing properties of reduced graphene oxide/Ni/multi-walled carbon nanotubes/Fe3O4 filled monolayer cement–based absorber

2019 ◽  
Vol 11 (1) ◽  
pp. 168781401882288 ◽  
Author(s):  
Yafei Sun ◽  
Min Chen ◽  
Peiwei Gao ◽  
Tianshu Zhou ◽  
Hongwei Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Scanning Electron Microscopy ◽  
Graphene Oxide ◽  
Pore Structure ◽  
Reduced Graphene Oxide ◽  
Reduced Graphene ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Scanning Electron

In this article, reduced graphene oxide/Ni/multi-walled carbon nanotubes/Fe3O4 filled paste is synthesized with the aim of developing a novel shielding material. To do so, nano-dispersion presenting homogeneous distribution is made by ultrasonic dispersing technology. Next, the effects of nano-absorbent content on the fluidity, mechanical strength, pore structure, resistivity, and absorbing reflectivity of paste are studied. At the end, the microstructure of composite is uncovered by scanning electron microscopy, Fourier transformer infrared, X-ray diffraction images as well as the pore size distribution and absorbing reflectivity are revealed. The results indicate that a small load of reduced graphene oxide and other nano-absorbents can significantly reduce the fluidity and resistivity of paste, but its pore structure is improved so that its mechanical properties are increased. Scanning electron microscopy images indicate that reduced graphene oxide promotes the increasing and thickening of the cement hydration products as well as the growth of a large number of flower-like and compact bulk crystals. Furthermore, the minimum reflectivity of −10.6 dB is obtained in the range of 2–18 GHz while the effective bandwidth of 16 GHz is obtained when reflectivity is less than −5 dB. This research provides a new pathway for the preparation of monolayer cement–based absorber.

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