Analyze the relationship between 'Chuquicamata' and 'Codelco' within the context of the input sentence.
Options: publisher, operator, parent organization, location of formation

SANTIAGO, July 28 World no.1 copper miner Codelco halted operations Tuesday at its key Chuquicamata mine as a week-long contract workers' strike intensified, chief executive Nelson Pizarro said.
operator