SU seems to be the fill of a smaller circular cut within the larger cut. It appears that at some point the larger cut was partially filled by the compact yellow layer which surrounds and extends under SU 8087, possibly around some sort of storage vessel. After this vessel was removed, 8087 was deposited in the resultant depression, and then 8064 was deposited on top, filling the rest of the cut. These elements are not preserved in the other circular cuts in this area, and thus this SU may help to understand the others.
PM1496 SU8087
Grey deposit beneath 8064.