In Jolinar's Memories (1999), Martouf puts the memory device on Sam behind her ear so that the Goa'uld won't see it. When Apophis completely activates the device, it is behind her ear. However, when the Jaffa guards throw her back in the cell with the rest of the team plus Martouf and her father, the imprint from the device is seen, not behind her ear, but on her temple.
Netu's volcanic explosions start small and get ever more powerful, which is atypical of volcanic behavior: prior to any volcanic eruption, the side vents and steam vents lessen in intensity, in some cases actually going out, as the pressure builds in the main magma chamber.