On the occurrence of microscale chemical patches in fractal aggregates

The occurrence of microscale chemical patches inside large marine fractal aggregates has a major role on the biogeochemical processes in the ocean interior. In the present work the concentrations of a diffusing compound around fractal aggregate assuming steady state conditions are computed using the Laplace equation. The results are in agreement with experimental observations, showing well developed chemical patches for large colloids and an adsorption process limited by diffusion, while the occurrence of chemical patches is highly dependent on the fractal dimension when the process is limited by reaction.