Injection of a Smart Water, with a modified and optimized ionic composition, is an environmentally friendly and cheap enhanced oil recovery (EOR) method. To be able to optimize the ionic composition to cause wettability alteration in the reservoir, one must understand the initial wetting of the reservoir. Experimental studies have confirmed that acidic material in the crude oil, especially negatively charged carboxylates, R−COO − , are the most important wetting parameters toward positively charged carbonate surfaces that dictate the rock wettability. The carboxylate molecules bond strongly to the carbonate surface, and these crude oil anchor molecules can only be removed from the calcite surface by chemical reactions. Generating representative core wettability during core restoration in the laboratory is important for doing realistic oil recovery studies, capillary pressure and relative permeability measurements. Water-wet outcrop chalk cores showing good reproducibility were used to study adsorption of carboxylic material onto chalk. Crude oil with a known acid number (AN) was flooded in different quantities through water-wet chalk cores containing 10% formation water saturation. The core wetting was evaluated by spontaneous imbibition tests, forced imbibition tests, and chromatographic wettability tests. The results of the work showed that the core wetting was determined by the amount of crude oil flooded through the core. The one core that had seen only 5 pore volumes (PV) of crude oil behaved much more water-wet than the core that had seen 15 PV of the same crude oil. Oil recovery by spontaneous imbibition was both lower and slower from the core that had seen the most oil, owing to the difference in wetting and capillary forces. With forced imbibition, viscous forces were introduced and the oil recovery immediately increased in both cores. The increase in oil recovery from the most water-wet core was larger than that of the less water-wet core, despite the residual oil saturation and, consequently, the EOR potential being lower in the most water-wet core. This suggested that the capillary forces not only influenced the spontaneous imbibition but also the forced imbibition, leading to a difference in recovery, which was related to a difference in wetting.

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The aim of this article is to illuminate the effect of morphology and material used in the wallscape of urban space in creating a sense of place.