A cloud of ash from an erupting volcano in southern Chile has – for a third day, Tuesday – disrupted air travel in South America, Australia and New Zealand, causing widespread delays. More than 60,000 passengers have been stranded.

While flights in some areas have resumed, including Melbourne, planes to and from New Zealand and Adelaide, Australia remain grounded Tuesday.

The volcano in the Puyehue-Cordon Caulle chain in Chile has been erupting for several days, putting South American air travel into chaos as it spews ash high into the atmosphere, spreading eastward around the globe until reaching Australia, New Zealand and beyond in the Pacific.

In addition to Argentina and Chile, flights have been disrupted in the South American countries of Brazil and Uruguay.

A flight carrying U.N. Secretary-General Ban Ki-moon to Buenos Aires late Sunday was diverted to Cordoba in northern Argentina because of the ash, which can damage aircraft bodies and engines. Mr. Ban was forced to travel to Buenos Aires by bus overnight for a meeting with Argentine President Cristina Fernandez de Kirchner.