Retention of Nanoparticles: From Laboratory Cores to Outcrop Scale

Figure 1

Irreversible and reversible retention sites for NPs illustrated using (a) a SEM picture of a sand grain from crushed Boise sandstone sieved between the size range of 90–105 μm (adapted from [46]) and (b) a schematic of rough sand grain surface with NPs. Red circles represent NPs trapped permanently, whereas black circles represent NPs that have the potential to escape from their site of retention.