title: Quantifying mineral surface energy by scanning force microscopy.
abstract: Fundamental understanding of the wettability of carbonate formations can potentially be applied to the development of oil recovery strategies in a complex carbonate reservoir. In the present study, surface energies of representative carbonate samples were evaluated by direct quantitative force measurements, using scanning force microscopy (SFM) at sub-micron scale, to develop a reliable method to predict reservoir wettability. Local adhesion force measurements were conducted on appropriate calcite and dolomite samples and performed in air as well as in the presence of polar and nonpolar fluids. This study demonstrated that, by comparing measurements of adhesion forces between samples of the same mineral in different fluids, it is feasible to determine the surface energy of a given mineral as well as its polar and nonpolar components. The derived values are in agreement with literature. A proof-of-principle protocol has been established to quantify surface energy using SFM-based adhesion measurements. This novel methodology complements the conventional contact angle measurement technique, where surface energy can only be examined at large length scale. The reported methodology has great potential for further optimization into a new standard method for fast and accurate surface energy determination, and hence provides a new tool for reservoir rock wettability characterization.
authors.affiliation: Schlumberger Middle East, S.A., Schlumberger Dhahran Carbonate Research Center, Dhahran Techno Valley, P.O. Box 39011, Dammam 31942, Saudi Arabia.
authors.forename: Bastian
authors.initials: B
authors.lastname: Sauerer
authors.affiliation: Schlumberger Moscow Research, Pudovkina 13, Moscow 119285, Russia.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Stukan
authors.affiliation: Schlumberger Middle East, S.A., Schlumberger Dhahran Carbonate Research Center, Dhahran Techno Valley, P.O. Box 39011, Dammam 31942, Saudi Arabia. Electronic address: WAbdallah@slb.com.
authors.forename: Wael
authors.initials: W
authors.lastname: Abdallah
authors.affiliation: Department of Chemical & Process Engineering, University of Strathclyde, Montrose Street, Glasgow G1 1XJ, UK.
authors.forename: Maryam H
authors.initials: MH
authors.lastname: Derkani
authors.affiliation: Department of Physics, Scottish Universities Physics Alliance (SUPA), University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, UK.
authors.forename: Maxim
authors.initials: M
authors.lastname: Fedorov
authors.affiliation: Reservoir Characterization Department, Saudi Aramco, Dhahran 31311, Saudi Arabia.
authors.forename: Jan
authors.initials: J
authors.lastname: Buiting
authors.affiliation: School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. Electronic address: z.j.zhang@bham.ac.uk.
authors.forename: Zhenyu J
authors.initials: ZJ
authors.lastname: Zhang
keywords: Calcite; Dolomite; SFM; Surface energy; Wettability