About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

Environmental Geosciences (DEG)

Abstract

DOI: 10.1306/eg.04021515002

Carbon dioxide sealing capacity: Textural or compositional controls? A case study from the Oklahoma Panhandle*

Constantin Cranganu1 and Hamid Soleymani2

1The Graduate Center, Brooklyn College, The City University of New York, 2900 Bedford Avenue, Brooklyn, New York 11210; [email protected]
2Earth and Environmental Science, The Graduate Center, The City University of New York, 365 Fifth Avenue, Room 4306, New York, New York 10016; [email protected]; [email protected]

*This article represents an extension of a presentation made at AAPG 43rd Eastern Section, London, Ontario, Canada, September 27–30, 2014, and posted at .


ABSTRACT

One of the challenges confronting carbon dioxide capture and sequestration (CCS) in geologic media over extended periods of time is determining the caprock sealing capacity. If the pressure of supercritical carbon dioxide EG15002eq1 injected in the repository overcomes the caprock sealing capacity, leaking of EG15002eq2 may enter other porous formations, compromising the storage formation, or even may go back to the atmosphere, and thus the process of sequestration becomes futile.

Carbon dioxide sealing capacity is controlled by two groups of parameters: (1) texture (e.g., the pore-throat size, distribution, geometry, and sorting; median grain size, porosity, degree of bioturbation, specific surface area, preferred orientation of matrix clay minerals, orientation, and aspect of ratio of organic particles) and (2) composition (mineralogical content, proportion of soft, deformable mineral grains to rigid grains, organic matter content, carbonate content, silt content, cementation, ductility, compaction, and ash content). The primary goal of this study was to investigate several parameters listed above and to estimate their respective contributions to sealing capacity to better understand its role in shale and carbonates. To assess the effect of textural and compositional properties on EG15002eq3 maximum retention column height, we collected 30 representative core samples from caprock formations in three counties (Cimarron, Texas, and Beaver) in the Oklahoma Panhandle. The study area was chosen because it hosts three depleted gas fields with a storage capacity of more than 35 million bbl and is situated at a crossroad leading to some significant EG15002eq4 stationary sources from North Texas, South Kansas, and northern Oklahoma. We used mercury injection porosimetry, scanning electron microscopy (SEM), Sedigraph energy dispersive spectra (EDS), x-ray diffraction (XRD), Brunauer–Emmett–Teller-specific surface area, and total organic carbon (TOC) measurements to assess textural and compositional properties of collected samples.

The range of EG15002eq5 column height for the samples used in this study is between 0.2 and 1358 m (0.66 and 4455 ft). The average EG15002eq6 column height is 351 m (1152 ft). The depth interval approximately 1400 m (4593 ft) could reach relatively high values of EG15002eq7 column height, up to 1200 m (3937 ft). The above-mentioned interval is composed of mainly Cherokee and Morrowan Formations (shale seals).

Principal component analysis (PCA) was carried out to infer the possible relationships between textural and compositional parameters.

Generally, composition of our samples (shales vs. carbonates and sandstones) indicates a relatively stronger control on caprock sealing capacity, although individual mineral makeup of shale samples seems not correlated with EG15002eq8 retention column heights. In the same time, many textural parameters play a significant role in determining the sealing capacity of carbonate caprocks.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24