A 5.3 earthquake shook Victoria, Australia tonight. That's not massive, but it's one of the biggest ever in Australia. Would seem to fit into your chain reaction theory. Hope we don't get a 'biggest ever' earthquake here. Though the dogs were going nuts last night.
"LARGE areas of Victoria, including Melbourne, were rocked last night by the state's biggest earthquake in more than a century.

The quake, measuring 5.3 on the Richter scale, struck at 8.53 pm. It rattled buildings and frightened residents from Gippsland to the western district, and almost as far north as the NSW border."

Read more: http://www.theage.com.au/victoria/quake-shakes-state-20120619-20m88.html#ixzz1yFV39ZKw