Drilling continues...., page-37

I'll have to watch it again and I might be able to see the answer, but say we're drilling 800 m and the part we are particualy interested in is from 650 to 750 metres, does that mean that "rubbish broken rock" is collected for the first 650 m (and washed back to the surface) and then from 650 they start to take out core samples? ... Raises the question ... does that mean every new 10 metres or so they have to retrieve the whole 660 metres in order to take of the new 10 m core off at the end, just added ... Then after, return it all down again to get the next 10 m length - 660 to 670 ... ??? ... repeating the process 10 times to get the cores from 650 to 750 to the surface?