A New Method to Quantify Wettability from Resistivity Measurements: Workflow Development and Experimental Core-Scale Verification
- Chelsea Newgord (The University of Texas at Austin) | Artur Posenato Garcia (The University of Texas at Austin) | Zoya Heidari (The University of Texas at Austin)
- Document ID
- Society of Petroleum Engineers
- SPE Europec featured at 81st EAGE Conference and Exhibition, 3-6 June, London, England, UK
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Petroleum Engineers
- 4.3.4 Scale, 2.6 Acidizing, 5.6.1 Open hole/cased hole log analysis, 5.4 Improved and Enhanced Recovery, 2 Well completion, 1.6 Drilling Operations, 2.5.2 Fracturing Materials (Fluids, Proppant), 5.4 Improved and Enhanced Recovery, 5.6 Formation Evaluation & Management, 5 Reservoir Desciption & Dynamics, 2.4 Hydraulic Fracturing, 1.6.9 Coring, Fishing, 1.1 Well Planning
- Wettability, Pore Geometry, Mixed-Wet Rocks, Resistivity Measurements
- 2 in the last 30 days
- 190 since 2007
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The wettability of reservoir rocks impacts many aspects of well planning and production, from estimating hydrocarbon saturation to enhanced oil recovery. Wettability is often experimentally quantified through laboratory measurements; however, in-situ wettability assessment is challenging. In this work, we introduce a new method to quantify wettability using resistivity measurements obtained from either well logs or core measurements. The objectives of this paper are (i) to introduce a resistivity-based wettability index from our recent analytically-derived resistivity model that takes into account wettability and (ii) to verify the reliability of the new resistivity-based wettability index using Amott Index, U.S. Bureau of Mines (USBM), and/or contact angle wettability measurements as reference.
We quantify the resistivity-based wettability index using our new analytically-derived resistivity model which requires as inputs the resistivity of the rock-fluid system and brine, water saturation, porosity, and pore-geometry-related parameters. Water saturation and porosity can be estimated from the interpretation of borehole geophysical or core measurements. The pore-geometry-related parameters can be estimated from image analysis performed on three-dimensional pore-scale images (e.g. micro-computed tomography) or through a physics-based calibration method. Next, we calculate the resistivity-based wettability index by minimizing the error between the measured and predicted resistivity of the rock-fluid system. To verify this method, we prepare core samples covering a wide range of wettability states and saturation levels. We vary the wettability of the samples by injecting brine, an anionic surfactant solution, or a naphthenic acid and decane solution to make the core samples water-, mixed-, or oil-wet, respectively. Finally, we obtain the resistivity-based wettability index in the core samples and verify its reliability by comparing the estimates against the Amott Index and the contact angle measurements. We also used previously documented data in Berea sandstone for further verification of the new method.
We successfully demonstrated the reliability of the introduced resistivity-based wettability index for limestone and sandstone core samples. The resistivity-based wettability indices were in agreement with both Amott and USBM Indices for the limestone and sandstone samples, respectively. The average absolute difference between the resistivity-based wettability index and the Amott and USBM Indices was less than 0.4 for all the core samples documented in this paper. The outcomes of this work can potentially be used for assessment of wettability from borehole geophysical measurements, to deliver in-situ properties of rocks in real-time. Additionally, the new resistivity model consists only of physically meaningful parameters and minimizes calibration efforts. Furthermore, if the wettability, porosity, and pore-geometry-related parameters are known, then we can use this resistivity model to obtain water saturation without the need for calibration.
|File Size||1 MB||Number of Pages||15|
Abledu, K.O. and Laird, D.N. 1992. Measurement of Substation Rock Resistivity. Transactions on Power Delivery 7 (1) 295-301. https://doi.org/10.1109/61.108921.
Amott, E., 1959. Observations Relating to the Wettability of Porous Rock. Journal of Petroleum Science and Engineering 52 (1) 172-186. https://doi.org/10.1016/j.petrol.2006.3.008.
Anderson, W.G. 1986a. Wettability Literature Survey-Part 1: Rock/Oil/Brine Interactions and the Effects of Core Handling on Wettability. Journal of Petroleum Technology 38(10) 1125-1144. https://doi.org/10.2118/13932-PA.
Anderson, W.G., 1986b. Wettability Literature Survey-Part 2: Wettability Measurement. Journal of Petroleum Technology 38 (11) 1246-1262. https://doi.org/10.2118/13933-PA.
Archie, G.E. 1942. The Electrical Resistivity Log as an Aid in Interpreting Some Reservoir Characteristics. Transactions of the AIME 146 (1) 54-62. https://doi.org/10.2118/942054-G.
Donaldson, E.C., Thomas, R.D., and Lorenz, P.B. 1969. Wettability Determination and its Effect on Recovery Efficiency. Society of Petroleum Engineers Journal 9 (1) 13-20. https://doi.org/10.2118/2338-PA.
Gant, P.L., and Anderson, W.G. 1988. Core Cleaning for Restoration of Native Wettability. SPE Formation Evaluation 3 (1) 131-138. http://doi.org/10.2118/14875-PA.
Han, Y., Zhou, C., Yu, J., et al. 2019. Experimental Investigation on the Effect of Wettability on Rock-Electricity Response in Sandstone Reservoirs. Fuel 239 (1) 1246-1257. https://doi.org/10.1016/j.fuel.2018.11.072.
Li, K. and Firoozabadi, A. 2000. Experimental Study of Wettability Alteration to Preferential Gas-Wetting in Porous Media and its Effects. SPE Reservoir Evaluation and Engineering 3(2) 139-149. https://doi.org/10.2118/62515-PA.
McPhee, C., Reed, J. and Zubizarreta, I. 2015. Electrical Property Tests. Core Analysis: A Best Practice Guide 356-358. Elsevier, Waltham, MA. https://doi.org/10.2118/28140-PA.
Mohanty, K. and Salter, S. 1983. Multiphase Flow in Porous Media: Oil Mobilization, Transverse Dispersion, and Wettability. SPE Annual Technical Conference and Exhibition, San Francisco, California, USA, October 5-8. SPE 12127. https://doi.org/10.2118/12127-MS.
Montaron, B.A. 2007. A Quantitative Model for the Effect of Wettability on the Conductivity of Porous Rocks. SPE Middle East Oil and Gas Show and Conference, Manama, Bahrain, March 11-14. SPE-105041. https://doi.org/10.2118/105041-MS.
Neumann, A.W. and Good, R.J. 1979. Techniques of Measuring Contact Angles. Surface and Colloid Science 31-91. Springer, Boston, MA. http://doi.org/10.1007/978-1-4615-7969-4&#x005F;2.
Newgord, C., Garcia A.P., Rostami, A., and Heidari, Z. 2018. Improved Interpretation of Electrical Resistivity Measurements in Mixed-Wet Rocks: An Experimental Core-Scale Application and Model Verification. Petrophysics 59(5) 703-718. http://doi.org/10.30632/PJV59N5-2018a9.
Owen, J.E. 1952. The Resistivity of a Fluid-Filled Porous Body. Journal of Petroleum Technology 4 (7) 169-174. http://doi.org/10.2118/952169-G.
Sen, P.N. 1980. The Dielectric and Conductivity Response of Sedimentary Rocks. SPE Annual Technical Conference and Exhibition, Dallas, Texas, USA, September 21-24. SPE-9379. https://doi.org/10.2118/9379-MS.
Sweeney, S.A. and Jennings Jr, H.Y. 1960. Effect of Wettability on the Electrical Resistivity of Carbonate Rock from a Petroleum Reservoir. The Journal of Physical Chemistry 64 (5) 551-553. http://doi.org/10.1021/j100834a009.
Volkmann, J. and Klitzsch, N. 2015. Wideband Impedance Spectroscopy from 1 mHz to 10 MHz by Combination of Four-and Two-Electrode Methods. Journal of Applied Geophysics (114) 191-201. http://doi.org/10.1016/j.jappgeo.2015.01.012.