Termination of Chromosome Replication in Bacteria

The two replication forks generated at oriC must eventually come together and fuse to generate two complete new chromosomes. The forks meet in the terminus region (tr) there is a specific mechanism to ensure that they do not meet outside this region. 

Question What is the mechanism whereby fork meeting and fusion are restricted to the terminus region  

On most occasions the forks meet and fuse in the vicinity of TerC. TerC appears to be the most frequently utilized terminator, probably because the clockwise fork would get to this site before the anticlockwise fork reached Ter A. Presumably the terminators flanking the innermost ones function as back-ups when TerA or C fails. 

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