[2] At the time of the blackout, sufficiently many transmission lines and capacitor banks had been removed from service that the system was no longer in an (n-1)-secure state.
[2] The electric system in Turkey split in half at CET 09:36:11 and separated from the Central European (CE) synchronous zone, i.e. connecting lines to Greece and Bulgaria also tripped.
The Eastern part suffered from hydropower oversupply (41%) that wasn't able to flow westward.
Power plants tripped due to overfrequency and the initially oversupplied Eastern part collapsed at underfrequency values less than 47.0 Hz.
6.5 hours after the blackout - the Western and Eastern part were resynchronised, while the Turkish grid was already about 80% energized.