Rav,
Since you indicate that this may have happened suddenly, you should check with your local Conservation District Forester, Extension Forester, or professional consulting Forester to determine what the cause of death was and if the wood is infected and useable or will a require specific disposal.
If the problem is oak wilt, there could be some problem. If its oak die back, gypsy moth, etc. there may not be a problem. Its best to find out the "cause of death" first.