What is physical accretion, and what is an example of an accretion study?

What will be an ideal response?

Physical accretion involves the study of traces unintentionally left behind by human actors, and how they accumulate over time. The trace can be an accumulation of possessions, the amount of dust accumulated on a book, the layers of paint upon a rock, or even garbage. An example of studying accretion is Kephart and Berg's study of gang graffiti collected from various locations throughout a single city in Southern California. They were able to establish a typology of symbolic messages concealed in the various renderings of gang graffiti and to distinguish between certain categories of messages and tags (names and/or initials of individual artists left on walls, poles, and curbs).