Rock Properties of Berea Sandstone, Baker Dolomite, and Indiana Limestone

Abstract

A complete understanding of the various rock properties is essential in determining the rockfluid interactions that take place during coreflood experiments. Although Berea sandstone, Baker dolomite and Indiana limestone have been used by the petroleum industry as reference materials, very few data have been reported in the literature regarding their basic rock properties. This paper contains petrographic and petrophysical data for these rock types. Twelve representative samples were selected to study the variability and the relationship of several rock properties, including mineral content, grain and pore size, porosity, permeability, specific surface area, mercury capillary pressure, and electrokinetic properties. The results indicate: 1) the Upper Berea sandstone samples studied exhibit correlations between porosity, permeability, specific surface area, and various parameters obtained from the mercury capillary pressure analyses that may be used to predict certain rock properties, 2) Baker dolomite and Indiana limestone contain a small amount of clays and organic matter, 3) These carbonates show a bimodal pore throat size distribution based on mercury capillary pressure analyses, and 4) The surface charges of these rocks are very dependent on the brine composition and pH. The specific surface area and surface charge data can be used to determine the amount of chemical retention during corefloods using these or similar reservoir rocks. This information is necessary to optimize chemical processes used in the oilfield.

Wettability and Oil Recovery by Imbibition and Viscous Displacement from Fractured and Heterogeneous Carbonates

“…However, Churcher et al (1991) reported that Indiana limestone showed large variations in both porosity (12.1 to 21.1%) and permeability (4 to 57 mD) for the three tested samples. The two Baker dolomite samples, other than showing porosity difference, appeared to have thin layers of organic acids absorbed on the rock surfaces.…”

“…Very strongly water-wet rocks would have an index of unity. Churcher et al (1991) obtained comparable values of Amott Index to water and recommended extraction with a chloroform/methanol mixture for Baker dolomite samples to obtain uniform wetting before using them in flow experiments but did not test this recommendation.…”

“…To date, no comparable model rock has been adopted widely for study of carbonates. Indiana limestone, which, for example, has sometimes been employed in past studies, exhibits a large degree of macroscopic heterogeneity at the core scale (Churcher et al, 1991). In the present work, change in wettability induced by adsorption from crude oil was investigated for three selected outcrop limestones: a reef boundstone from Mt.…”

Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir Analysis

“…Figure 2.22 represents the total single-collector contact efficiency, and the magnitude of individual collision mechanisms (diffusion, interception and sedimentation), calculated for the silica particles used in this study, with particle density of 2.2 g/cm 3 , average grain size for Berea sandstone of 150 µm (Churcher et al, 1991) with porosity of 21%, fluid velocity of 1.5×10…”

“…It is well understood that smaller grain size corresponds to smaller pore size for certain types of grain packing. For the Berea sandstone used in this study, an average grain size of 150 µm was assumed, based on Churcher et al (1991). Considering the silica particles of 2 and 5 µm, the ratio of ( ⁄ ) would be 0.013 and 0.033, respectively.…”