The asteroid which created the Vredefort impact crater in South Africa is estimated to have been between 10 and 16 km in diameter (the uncertainty is due to the age of the crater, which is more than 2 billion years).
Assuming the maximum estimate is correct, how deep could this asteroid have penetrated into the Earth's crust, and would the resulting crater have become filled or partly filled with magma like some of those on the moon?
The reason no mass extinction is associated with it is that at that time the most complex life on Earth was only single-celled. It should be remembered that the crust was thinner in those days, as was the case with the magma-filled craters on the moon.
Another important factor is the sped of the asteroid at the moment of impact, which we cannot know,therefore an average of mega-meteorite velocities will do. It is important to read this question carefully before answering,otherwise I have to keep repeating myself.