The phrase "which was triggered by" is grammatically correct and can be used in written English.
Example: The fire alarm, which was triggered by a faulty wire, caused the entire building to evacuate.
He added: "The avalanche was caused by heavy snow, which was triggered by a strong wind.
About 50 MPs out of 650 were present for the debate, which was triggered by a petition signed by more than half a million people.
It also contested the Batley and Spen byelection, which was triggered by the death of Cox, winning 1% of the vote.
"This is outrageous given the plight of elephants, which was triggered by these same countries selling ivory in 2008 to China and Japan.
Cameron visited the constituency six times during the campaign, which was triggered by the resignation of Labour's Ian Gibson following the MPs' expenses scandal.
The findings will help to explain why Farage decided not to contest the Newark byelection, which was triggered by the resignation of the former Tory MP Patrick Mercer.
Initially, I didn't want to get too involved in the Great "Homeland" Plausibility War of December 3 , 2012 which was triggered by Sunday night's episode, "Broken Hearts".
Kenneth Baker followed with his barmy Dangerous Dogs Act, which was triggered by a spate of tabloid stories about rottweilers biting babies.
But Woolfe had been under pressure to withdraw after the fracas in Strasbourg, which was triggered by the revelation that he had considered defecting to the Conservatives.
Enver Oren, the family head, pins the blame on last December's liquidity crunch, which was triggered by a criminal probe into ten failed banks.
The Malheur occupation, which was triggered by disputes over ranchers' use of public lands, has also been a theatrical public argument about the scope of legal violence in America.
