Pore - Throat size distribution indices and their relationships with the petrophysical properties of conventional and unconventional clastic reservoirs

Sharawy, Mohamed S. El; Gaafar, Gamal Ragab

doi:10.1016/j.marpetgeo.2018.10.006

Cited by 17 publications

(7 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One hundred and thirty‐nine samples were analysed with AutoPore IV9500 mercury porosimeter to characterize capillary pressure curves and parameters, PSD, as well as pore‐throats connectivity (El Sharawy & Gaafar, 2019; Lai, Wang, Wang, et al, 2018; Pittman, 1992; Swanson, 1981). When the intrusion pressure reached the maximum pressure of 30 MPa, the mercury was expelled from the sample as the pressure progressively decreased.…”

Section: Samples and Methodologymentioning

confidence: 99%

Diagenetic controls on pore structure variations in fan deltaic sandstones of the Eocene Shahejie Formation, Bohai Bay Basin, China: Implications for reservoir quality and oiliness heterogeneities

et al. 2023

Geological Journal

View full text Add to dashboard Cite

The fan deltaic sandstones in the third section of the third member of the Eocene Shahejie Formation (Es33) are important hydrocarbon exploration targets in the northern Nanpu sag, Bohai Bay Basin, China. The Es33 sandstones are characterized by highly variable pore structures. A total of 364 Es33 sandstone samples were measured by a series of petrological and petrophysical analyzes to investigate these variations and their controls on reservoir quality and oiliness heterogeneities. The heterogeneity of Es33 sandstone can be manifested by type I, type II and type III pore structures. Primary intergranular pores and dissolution pores were the main storage spaces for type I sandstones, while dissolution pores and intercrystalline pores were the main storage spaces for type II and type III sandstones, respectively. These results indicate that compaction is the main factor in the loss of primary intergranular porosity, with an average loss of 78%. The grain size controlled the preservation of primary pores in Es33 sandstones with a carbonate cement content of less than 6%. The different types of clay minerals have various effects on the pore structure. Chlorite plays an active role in the preservation of intergranular pores and the improvement of reservoir quality, while mixed layers of illite and smectite greatly reduced the pore size and connectivity and lowered the reservoir quality. The Es33 sandstones have undergone a more open diagenetic system. Dissolution significantly increased the porosity of type I and type II sandstones with more primary intergranular pores, but exerted a minor role in contributing to the permeability. Furthermore, a pore‐throat radius of approximately 0.4 μm is considered to be the threshold for oil accumulation in Es33 fan deltaic sandstones.

show abstract

Section: Samples and Methodologymentioning

confidence: 99%

Diagenetic controls on pore structure variations in fan deltaic sandstones of the Eocene Shahejie Formation, Bohai Bay Basin, China: Implications for reservoir quality and oiliness heterogeneities

et al. 2023

Geological Journal

View full text Add to dashboard Cite

show abstract

“…The computed values of fractal dimension based on these models differ from each other. Their relationship with the rock heterogeneity is always similar in a way that the greater the fractal dimension, the stronger the heterogeneity of the rock's pore structure (Li, 2010;Li et al, 2017;Zhang et al, 2017;Song et al, 2018;Xiao et al, 2018;Zhang et al, 2018;Sharawy and Gaafar, 2019). This is because these models are derived theoretically and interrelated on the basis of fractal modeling of porous media (Li, 2004;Li et al, 2010;Song et al, 2018).…”

Section: Fractal Dimension Calculationmentioning

confidence: 99%

“…Several methods can be utilized to characterize the heterogeneous pore structure of carbonate rocks, including their pore geometry, connectivity and size distribution. These techniques include optical microscopy, scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), mercury intrusion capillary pressure (MICP), nitrogen gas adsorption (N2GA), nano X-ray computed tomography facility (CT), nuclear magnetic resonance (NMR), and digital image analysis (Rezaee et al, 2012;Anovitz et al, 2013;Clarkson et al, 2013;Norbisrath et al, 2015;Gundogar et al, 2016;Cao et al, 2018;Njiekak et al, 2018;Xiao et al, 2018;Zhao et al, 2018;El Sharawy and Gaafar, 2019;Górniak, 2019). The combined use of multiple pore structure characterization methods (such as optical microscope, SEM, and the combination of MICP and N2GA tests) can reveal the wide range of pore sizes and pore size distributions (PSDs) from the nanometer to the micrometer scale (Ross and Bustin, 2009;Schmitt et al, 2013;Cao et al, 2015;Gao et al, 2019), their full aperture and the overall pore throat structure of tight carbonate cap rocks (Wu et al, 2019a).…”

Section: Introductionmentioning

confidence: 99%

“…The capillary leakage limits the capacity for retention of natural hydrocarbon accumulations (Vavra et al, 1992;Ingram et al, 1997;Wilkinson et al, 2014). The sealing capacity of carbonate cap rocks is controlled by the capillary pressure (McPhee et al, 2015;Wu et al, 2018a) and can be estimated by measuring the displacement pressure at 10% mercury saturation during MICP analysis (El Sharawy and Gaafar, 2019). This technique has recently been adopted by Lohr and Hackley (2018) to evaluate the sealing capacity of marine shales from the Tuscaloosa Group in Mississippi (USA).The fractal geometry theory can be used to study the features of pore networks of sedimentary rocks and to characterize reservoirs (Pfeifer and Avnir, 1983).…”

Section: Introductionmentioning

confidence: 99%

“…The fractal dimensions calculated through different models, such as the Brunauer-Emmett-Teller (BET) (Brunauer et al, 1938), the Barret-Joyner-Halenda (BJH) (Joyner et al, 1951) and the Frenkel-Halsey-Hill (FHH) models (Avnir and Jaroniec, 1989) quantitatively reflect the heterogeneity of rock pore structures. The fractal characteristics of carbonate rocks have historically been less studied than those of tight sandstone and shale reservoirs (Clarkson et al, 2013;Cao et al, 2015;Zhang et al, 2018;El Sharawy and Gaafar, 2019). This is partly because carbonate rocks undergo complex diagenesis (He et al, 2016;Adelinet et al, 2019), resulting in heterogeneous pore connectivity, and therefore pore structures that are challenging to characterize quantitatively (Krohn, 1988;Lesniak and Such, 2006;Gundogar et al, 2016;Wu et al, 2019a).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Fractal characteristics of pore networks and sealing capacity of Ordovician carbonate cap rocks: A case study based on outcrop analogues from the Tarim Basin, China

Wu¹,

Tang²,

Gomez‐Rivas³

et al. 2021

Bulletin

View full text Add to dashboard Cite

. Jun Wu is grateful to the China Scholarship Council (201806400037) for supporting his study as a joint Ph. D. candidate at the University of Barcelona. Enrique Gomez-Rivas acknowledges funding 2 by the AGAUR-Agència de Gestió d'Ajuts Universitaris i de Recerca of the Generalitat de Catalunya ("Beatriu de Pinós" fellowship 2017SGR-824), and the Spanish Ministry of Science, Innovation and Universities ("Ramón y Cajal" fellowship RYC2018-026335-I). We are grateful to Editor-in-Chief Prof. Robert Merrill, Associate editor Prof.Barry Jay Katz and two anonymous reviewers for their thoughtful suggestions and critical comments that significantly improved the manuscript.Abstract：Understanding and predicting the main controls on the sealing capacity of carbonate cap rocks is of great significance for ultra-deep carbonate reservoir exploration and production. This study focuses on revealing the pore networks and sealing capacity of the Ordovician carbonate cap rocks in the Tarim Basin, by analyzing samples from outcrop analogs using optical and scanning electron microscopy and a combination of mercury intrusion capillary pressure and nitrogen gas adsorption. Three classes of cap rocks are defined here according to their pore throat structure, fractal dimension and sealing capacity. These carbonate cap rocks are dominated by limestones and dolomitic limestones. Four pore types are identified: microfracture, intragranular pore, intercrystalline pore and intracrystalline pore. Six pore structure types show multiscale variability from macropores to micropores. The pore structures present multiple fractal behaviors, with fractal dimensions showing an increasing trend as the pore diameter decreases. The cover coefficient, a parameter that allows characterization of the cap rock sealing performance, shows an increasing trend along with increasing the fractal dimension of pore structure. The average cover coefficients of six pore 3 structure types not only show good correlations (either exponential or linear) with certain fractal dimensions, but they also demonstrate a strong positive correlation with the average fractal dimension. These results suggest that the sealing capacity of the studied rocks increases with increasing fractal dimension. The sealing performance of cap rocks significantly decreases with increasing the amount of macropores. This work provides a relevant case study for further understanding of pore structures and sealing capacity of carbonate cap rocks.

show abstract

Development and Identification of Petrophysical Rock Types for Effective Reservoir Characterization: Case Study of the Kristine Field, Offshore Sabah

et al. 2021

View full text Add to dashboard Cite

Pore - Throat size distribution indices and their relationships with the petrophysical properties of conventional and unconventional clastic reservoirs

Cited by 17 publications

References 6 publications

Diagenetic controls on pore structure variations in fan deltaic sandstones of the Eocene Shahejie Formation, Bohai Bay Basin, China: Implications for reservoir quality and oiliness heterogeneities

Diagenetic controls on pore structure variations in fan deltaic sandstones of the Eocene Shahejie Formation, Bohai Bay Basin, China: Implications for reservoir quality and oiliness heterogeneities

Fractal characteristics of pore networks and sealing capacity of Ordovician carbonate cap rocks: A case study based on outcrop analogues from the Tarim Basin, China

Development and Identification of Petrophysical Rock Types for Effective Reservoir Characterization: Case Study of the Kristine Field, Offshore Sabah

Contact Info

Product

Resources

About