Pore structural characteristics and methane adsorption capacity of transitional shale of different depositional and burial processes: a case study of shale from Taiyuan formation of the Southern North China basin

AbstractPore structural characteristics and methane adsorption capacity are two significant aspects affecting shale gas potential, but the impact of deposition and burial processes on these two aspects is not clear. Hence, the shale samples of Taiyuan Formation deposited continuously and experienced multi-stage tectonic uplift in Fuyang-Bozhou area of Southern North China Basin were collected in this study. Based on the total organic carbon content analysis, mineral composition determination, low-pressure CO2 and N2 adsorption, high-pressure methane adsorption and argon ion polishing-field emission scanning electron microscope observation. The impact of depositional and burial processes variation on shale reservoir physical properties and adsorption performance is studied. The results display that the pore types of shale samples which were continues deposited and experienced multi-stage tectonic uplift have no obvious differences, while the pore volume as well as specific surface area (SSA) of micropores and mesopores of shale samples under multi-stage tectonic uplift are larger significantly. Meanwhile, the roughness of shale pores increases also. The decrease of loading pressure caused by multi-stage tectonic uplift may be the main factor for the pore structure changes of shale sample. Compared with the continuous deposited samples, the shale samples under multi-stage tectonic uplift have stronger methane adsorption capacity, which is relevant to the greater SSA of micropores as well as mesopores. This study provides an example and new revelation for the influence of depositional and burial processes on shale pore structure and methane adsorption capacity.

Download Full-text

Quantitative characterization of pore network and influencing factors of methane adsorption capacity of transitional shale from the southern North China Basin

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-021-01340-w ◽

2021 ◽

Author(s):

Wen Liu ◽

Qiuchen Xu ◽

Haizhou Wang ◽

Peng Liu ◽

Ruiliang Guo ◽

...

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

Clay Minerals ◽

Influencing Factors ◽

North China ◽

Methane Adsorption ◽

Quantitative Characterization ◽

Petroliferous Basin ◽

North China Basin

AbstractQuantitative characterization of pore structure and analysis of influencing factors of methane adsorption are important segments in shale gas reservoir and resources evaluation and have not been systematically carried out in marine–continental shale series. A series of integrated methods, including total organic carbon (TOC) contents, Rock-Eval pyrolysis, mineral composition analysis, pore structure measurement, high-pressure CH4 adsorption analysis and FE-SEM observation, were conducted on 12 transitional shale samples of well WBC-1 in the southern North China Basin (SNCB). The results indicate that TOC contents of the transitional shales range from 1.03 to 8.06% with an average of 2.39%. The transitional shale consists chiefly of quartz, white mica and clay minerals. Interparticle pore, intraparticle pore, dissolution pore and microfracture were observed in the FE-SEM images. The specific surface area (SSA) of BET for the samples ranges from 3.3612 to 12.1217 m2/g (average: 6.9320 m2/g), whereas the DR SSA for the samples ranges from 12.9844 to 35.4267 m2/g (average: 19.67 m2/g). The Langmuir volume (VL) ranges from 2.05 to 4.75 cm3/g (average = 2.43 cm3/g). There is unobvious correction between BET and DR SSA with TOC contents, which means inorganic pores are the main component of pore space in the transitional shale from the SNCB. The relationship of SSA and pore volume shows that micropore has a greater impact on the CH4 adsorption capacity than mesopore–macropore in the transitional shale. Different from shales in other petroliferous basin, clay minerals are the primary factor affecting adsorption capacity of CH4 for transitional shale in this study. The pore structure of the transitional shale for this study is characterized by higher fractal dimension and more heterogeneous pore structure compared to shale in other petroliferous basin. This study provides an example and new revelation for the influencing factors of pore structure and methane adsorption capacity of marine–continental transitional shale.

Download Full-text

Investigation of the Pore Structure of Tight Sandstone Based on Multifractal Analysis from NMR Measurement: A Case from the Lower Permian Taiyuan Formation in the Southern North China Basin

Energies ◽

10.3390/en13164067 ◽

2020 ◽

Vol 13 (16) ◽

pp. 4067

Author(s):

Kaixuan Qu ◽

Shaobin Guo

Keyword(s):

Pore Structure ◽

Probability Density ◽

North China ◽

Lower Probability ◽

Tight Sandstone ◽

Quartz Content ◽

Thin Sections ◽

Taiyuan Formation ◽

Mineral Compositions ◽

North China Basin

Understanding the pore structure can help us acquire a deep insight into the fluid transport properties and storage capacity of tight sandstone reservoirs. In this work, a series of methods, including X-ray diffraction (XRD) analysis, casting thin sections, scanning electron microscope (SEM), nuclear magnetic resonance (NMR) experiment and multifractal theory were employed to investigate the pore structure and multifractal characteristics of tight sandstones from the Taiyuan Formation in the southern North China Basin. The relationships between petrophysical properties, pore structure, mineral compositions and NMR multifractal parameters were also discussed. Results show that the tight sandstones are characterized by complex and heterogenous pore structure, with apparent multifractal features. The main pore types include clay-dominated micropores and inter- and intragranular dissolution pores. Multifractal parameters of sandstone samples were acquired by NMR and applied to quantitatively describe the pore heterogeneity in higher and lower probability density regions (with respect to small and large pore-scale pore system, respectively). The multifractal parameter (D−10) of lower probability density areas has better correlation with the petrophysical parameters, which is more suitable for evaluating the reservoir properties of tight sandstone. However, the multifractal parameter (D10) of higher probability density areas is more conducive to characterize the pore structure of tight sandstone. Additionally, the mineral compositions of sandstone have a complex effect on multifractal characteristics of pores in different probability density areas. The D10 increases with the decrease of quartz content and increase in clay mineral content, whereas D−10 decreases with the increase in clay minerals and decrease of authigenic quartz content and feldspar content.

Download Full-text

Full-size pore structure characterization of deep-buried coals and its impact on methane adsorption capacity: A case study of the Shihezi Formation coals from the Panji Deep Area in Huainan Coalfield, Southern North China

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2018.10.100 ◽

2019 ◽

Vol 173 ◽

pp. 975-989 ◽

Cited By ~ 10

Author(s):

Qiang Wei ◽

Xianqing Li ◽

Jizhen Zhang ◽

Baolin Hu ◽

Wenwei Zhu ◽

...

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

North China ◽

Methane Adsorption ◽

Structure Characterization ◽

Full Size ◽

Huainan Coalfield ◽

Deep Area

Download Full-text

Geological controls on methane adsorption capacity of Lower Permian transitional black shales in the Southern North China Basin, Central China: Experimental results and geological implications

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2017.03.017 ◽

2017 ◽

Vol 152 ◽

pp. 456-470 ◽

Cited By ~ 23

Author(s):

Wei Dang ◽

Jinchuan Zhang ◽

Xiaoliang Wei ◽

Xuan Tang ◽

Qian Chen ◽

...

Keyword(s):

Adsorption Capacity ◽

North China ◽

Methane Adsorption ◽

Black Shales ◽

Experimental Results ◽

Central China ◽

Lower Permian ◽

Geological Implications ◽

North China Basin

Download Full-text

Changes in Pore Structure of Coal Caused by CS2 Treatment and Its Methane Adsorption Response

Geofluids ◽

10.1155/2018/7578967 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Run Chen ◽

Yong Qin ◽

Pengfei Zhang ◽

Youyang Wang

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

Gas Adsorption ◽

Recovery Process ◽

Micropore Volume ◽

Methane Adsorption ◽

Coal Bed ◽

Methane Recovery ◽

Before And After ◽

Key Issues

The pore structure and gas adsorption are two key issues that affect the coal bed methane recovery process significantly. To change pore structure and gas adsorption, 5 coals with different ranks were treated by CS2 for 3 h using a Soxhlet extractor under ultrasonic oscillation conditions; the evolutions of pore structure and methane adsorption were examined using a high-pressure mercury intrusion porosimeter (MIP) with an AutoPore IV 9310 series mercury instrument. The results show that the cumulative pore volume and specific surface area (SSA) were increased after CS2 treatment, and the incremental micropore volume and SSA were increased and decreased before and after Ro,max=1.3%, respectively; the incremental big pore (greater than 10 nm in diameter) volumes were increased and SSA was decreased for all coals, and pore connectivity was improved. Methane adsorption capacity on coal before and after Ro,max=1.3% also was increased and decreased, respectively. There is a positive correlation between the changes in the micropore SSA and the Langmuir volume. It confirms that the changes in pore structure and methane adsorption capacity due to CS2 treatment are controlled by the rank, and the change in methane adsorption is impacted by the change of micropore SSA and suggests that the changes in pore structure are better for gas migration; the alteration in methane adsorption capacity is worse and better for methane recovery before and after Ro,max=1.3%. A conceptual mechanism of pore structure is proposed to explain methane adsorption capacity on CS2 treated coal around the Ro,max=1.3%.

Download Full-text

Influence of solvents on pore structure and methane adsorption capacity of lacustrine shales: An example from a Chang 7 shale sample in the Ordos Basin, China

Journal of Petroleum Science and Engineering ◽

10.1016/j.petrol.2019.03.052 ◽

2019 ◽

Vol 178 ◽

pp. 419-428 ◽

Cited By ~ 4

Author(s):

Yan Cao ◽

Hui Han ◽

Hou-wu Liu ◽

Jian-chao Jia ◽

Wei Zhang ◽

...

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

Ordos Basin ◽

Methane Adsorption ◽

Shale Sample ◽

The Ordos Basin ◽

Influence Of Solvents

Download Full-text

Effect of nanometer pore structure on methane adsorption capacity in organic-rich shale

Petroleum Science and Technology ◽

10.1080/10916466.2018.1542443 ◽

2019 ◽

Vol 37 (11) ◽

pp. 1243-1250 ◽

Cited By ~ 1

Author(s):

Cheng Zhong ◽

Qirong Qin ◽

Cunhui Fan ◽

Dongfeng Hu

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

Methane Adsorption

Download Full-text

Effects of Pore Structure and Wettability on Methane Adsorption Capacity of Mud Rock: Insights from the Organic Matter/Clay Minerals Mixtures

10.3997/2214-4609.201903016 ◽

2019 ◽

Author(s):

P. Luo ◽

N.N. Zhong ◽

Z.P Guo

Keyword(s):

Organic Matter ◽

Pore Structure ◽

Adsorption Capacity ◽

Clay Minerals ◽

Methane Adsorption

Download Full-text

INVESTIGATION OF FRACTAL CHARACTERISTICS AND METHANE ADSORPTION CAPACITY OF THE UPPER TRIASSIC LACUSTRINE SHALE IN THE SICHUAN BASIN, SOUTHWEST CHINA

Fractals ◽

10.1142/s0218348x19400115 ◽

2019 ◽

Vol 27 (01) ◽

pp. 1940011 ◽

Cited By ~ 2

Author(s):

LEI CHEN ◽

ZHENXUE JIANG ◽

KEYU LIU ◽

WEI YANG ◽

SHU JIANG ◽

...

Keyword(s):

Pore Structure ◽

Adsorption Capacity ◽

Sichuan Basin ◽

Southwest China ◽

Upper Triassic ◽

Methane Adsorption ◽

Relative Pressure ◽

Pore Surface ◽

Fractal Characteristics ◽

The Sichuan Basin

To better understand the nanopore characteristics and their effects on methane adsorption capacity of shales, we performed fractal analysis of nine shale samples collected from the fifth member of Upper Triassic Xujiahe Formation in the Sichuan Basin, southwest China. [Formula: see text] adsorption results show that shales have different adsorption characteristics at relative pressure of 0–0.5 and 0.5–1. Two fractal dimensions [Formula: see text] and [Formula: see text] were calculated using the Frenkel–Halsey–Hill (FHH) equation. Results show that the methane adsorption capacity increases with the increase of [Formula: see text] and [Formula: see text], of which [Formula: see text] has a more significant influence on adsorption capacity than [Formula: see text]. Further studies indicate that [Formula: see text] represents the pore surface fractal characteristics caused by the irregularity of shale surface, whereas [Formula: see text] represents the pore structure fractal characteristics, which is mainly affected by shale components (e.g. TOC, clay minerals) and pore parameters (e.g. average pore diameter, micropores content). A higher [Formula: see text] corresponds to a more irregular pore surface, which provides more space for methane adsorption. While a higher [Formula: see text] indicates a more complex pore structure and a stronger capillary condensation action on the pore surface, which in turn enhances the methane adsorption capacity.

Download Full-text