Time eddy
A time eddy was a distortion in the space-time continuum. Anyone displaced through time would be covered in time particles and leave behind a space-time shadow.
History
When the Time Lords attempted to bring the Doctor's first incarnation to his future incarnations to help fight Omega, his transportation unit became trapped in a time eddy. (TV: The Three Doctors)
Whitaker used time eddies to transport dinosaurs from the past to 1970s London as part of Operation Golden Age. A 12th century peasant was inadvertently transported too. (TV: Invasion of the Dinosaurs)
When Borusa attempted to bring the Doctor's fourth incarnation and his companion Romana to the Death Zone, they became trapped in a time eddy. (TV: The Five Doctors)
Audrey Mohinson once created time eddies to make her immersive reality game Fugitives more realistic and therefore hold back the Ravagers. After witnessing them place Roman Centurions in 1959 London and Soviet Union tanks in the Battle of Waterloo, the Ninth Doctor and Nova worked to stop them without setting the Ravagers free. (AUDIO: Sphere of Freedom)
When travelling with Donna Noble, the Tenth Doctor believed that a time eddy was causing turbulence in the TARDIS. (AUDIO: The Forever Trap)
Zorgo attempted to trap the Twelfth Doctor in a time eddy, was was unsuccessful. (COMIC: Zorgo the Terrible)
The Thirteenth Doctor once got trapped in a time eddy. She contacted human and Zygon Osgood via text message at some point in 2020, complaining about the boredom it induced for her. (WC: The Zygon Isolation)
In the final moments of Atlantis, the Crystal of Kronos created a time eddy encompassing the entire city, infinitely extending its final moments in a temporally-anomalous manner. This turned it into a space-time Waypoint. When the Fourth Doctor visited this Atlantis with K9 Mark I, K9 began to malfunction, which the Doctor recognised immediately as an effect of the time eddy. He also noted that his TARDIS wasn't working, although this was part of a wider temporal crisis sweeping through the universe, which affected all his other incarnations. Like them, he was able to depart by using some of the Waypoint's vortex energy as emergency power for the TARDIS. Later, Martha tried to get to Atlantis in her "present", and called for UNIT backup, only for it to arrive in the form of a young Liz Shaw, from the earlier generation of UNIT. (GAME: Lost in Time)
Narvin, the Fourth Doctor, and Adric were subject to a time eddy on Bellascon due to time experiments being used to change the timeline, though only the Doctor and Narvin were aware of its effects. Adric was temporarily erased from time due to the eddy, but was restored by Narvin altering events to their correct course. (AUDIO: Erasure)