/pdf/high-resolution-x-ray-computed-tomography-in-geosciences-a-3sj7249knj.pdf

High-resolution X-ray computed tomography in geosciences: A review of the current technology and applications

Comparisons of pore size distribution: A case from the Western Australian gas shale formations

Wettability alteration is an important method to increase oil recovery from oil-wet carbonate reservoirs. Chemical agents are used as wettability modifiers in carbonate systems; however, the role of Nanoparticles in this field is still in its infancy and consequently has attracted the attention of many researchers in the last decade. In this work, the impact of SiO2 Nanoparticles on the wettability of a carbonate reservoir rock was experimentally studied. The impact of these Nanoparticles on the wettability of carbonate systems is still in its infancy. For this purpose, the effect of Nanofluid’s concentration on wettability and interfacial tension were investigated to determine the optimum concentration of Nanofluid for injection into core samples. The result suggests that a concentration of 4 g/L of Nanofluid could significantly alter the wettability of the rock from a strongly oil-wet to a strongly water-wet condition. Moreover, we studied the Nanofluids’ potential in enhanced oil recovery of oil-wet core plugs. The results show that a considerable amount of oil can be recovered right after start of water injection to the aged core plug with Nano fluid.

/pdf/experimental-investigation-of-sio2-nanoparticles-on-enhanced-3fjak66i85.pdf

Experimental investigation of SiO2 nanoparticles on enhanced oil recovery of carbonate reservoirs

Porosity and permeability characterization of coal: A micro-computed tomography study

Carbonate rocks are well known for their complex petrophysical behavior where, in contrast to siliciclastic rocks, different parameters, including porosity and permeability, usually are not directly related. This behavior is the result of thorough reorganization of porosity during diagenesis, and it turns prediction of reservoir quality of carbonate rocks into a challenge. The study presented here deals with the problem of utilizing NMR techniques in prediction of petrophysical properties in carbonates. We employ a visual porosity classification as a priori knowledge for better interpreting NMR data for prediction purposes. This allows for choice of suitable T2 cutoff values to differentiate movable from bound fluids adapted for the specific carbonate rock, thus resulting in better interpretation of NMR data. The approach of using a genetic pore type classification for adapting the conventional method for T2 cutoff determination, which originally was developed for siliciclastic rocks, is promising. Similarly, for permeability determination on the basis of NMR measurements, the classification of carbonate rocks based on porosity types also shows potential. The approach implemented here has the promise to provide a basis of standardized interpretation of NMR data from carbonate rocks.

NMR measurements in carbonate rocks: Problems and an approach to a solution

bility due to large permeability contrasts. The most accurate upscaling
technique is employing Darcy’s law. A key part of the study is the establishment of porosity transforms between highresolution
and low-resolution images to arrive at a calibrated porosity map to constraint permeability estimates for the whole
core.

Permeability Upscaling for Carbonates from the Pore-Scale Using Multi-Scale Xray-CT Images

Fifty Years of Wettability Measurements in the Arab-D Carbonate Reservoir

Results and discussions in this paper relate to a Lower Cretaceous carbonate reservoir located in southeastern Saudi Arabia. It is a heterogeneous carbonate formation with various facies due to diagenetic alteration of the original rock fabric. The reservoir is large and prolific with mixed-wet characteristics. Because of the economic importance and variety of oil-recovery mechanisms operative or possible in the reservoir, the multiphase recovery behavior has been extensively studied. Also, various wettability tests were carried out using Amott and USBM methods. This paper describes the variation in wettability and relative permeability of Lower Cretaceous carbonate reservoir and the multi-phase simulations of the experimental results. It shows that measurements are consistent with recent theories of the relationship between water saturation, relative permeability, and wettability as described by Jadhunadan and Morrow, 1991. However, the results indicate that the wettability of the reservoir changes from water-wet low on structure near the oil/water contact to mixed or neutral wet behavior higher on structure. Oil-wetting character increases towards the top of oil column and is correlated to decreasing water saturation. The results revealed that changes in wettability are accompanied by changes in waterflood efficiency and facies of deposition.

https://www.ux.uis.no/~s-skj/ipt/Proceedings/SCA.1987-2004/1-SCA2001-03.pdf

James J. Funk

Papers

Permeability Upscaling for Carbonates from the Pore-Scale Using Multi-Scale Xray-CT Images

Fifty Years of Wettability Measurements in the Arab-D Carbonate Reservoir

Wettability and Relative Permeability of Lower Cretaceous Carbonate Rock Reservoir, Saudi Arabia

Techniques for Extracting Reliable Density and Porosity Data From Cuttings

Calibration of Permeability Derived from NMR Logs in Carbonate Reservoirs