According to MMA Fighting:
The first two quarterfinal bouts will take place on Feb. 12, with Fedor Emelianenko taking on Antonio Silva, while Sergei Kharitonov will face Andrei Arlovski. Earlier Tuesday, MMA Fighting reported Emelianenko's contract extension with Strikeforce, paving the way for his entrance into the field.[UPDATE] - Tournament bracket via Strikeforce.com:
The other two quarterfinal bouts include Josh Barnett facing Brett Rogers and Alistair Overeem taking on Fabricio Werdum, the last man to beat Emelianenko.
While the Emelianenko-Silva and Kharitonov-Arlovski fights will take place at the Izod Center in East Rutherford, New Jersey, the location and date of the second set of quarterfinals is still to be determined.