An Alberta petition to trigger a referendum on independence from Canada, driven in part by a belief that the government in Ottawa hasn’t done enough to accelerate projects to expand oil production, reached a deadline for signatures on Saturday. | BLOOMBERG Alberta, the major oil-producing province of Canada, is one step closer to a referendum on independence after leaders of a separatist group said they’ve gathered more than enough signatures to force a vote. The group, Stay Free Alberta, had until May 2 to collect roughly 178,000 signatures on their petition for a provincewide vote. On Monday, organizers said they collected more than 301,000 signatures to submit to Elections Alberta, the independent elections agency. If the referendum goes ahead, it would ask: “Do you agree that the Province of Alberta should cease to be part of Canada to become an independent state?” But there are still a number of obstacles.…