The number of mass layoffs in Alberta so far this year has nearly doubled compared to the totals for 2013 and 2014 combined, according to provincial data.

By law, employers in Alberta are required to give the provincial government written notice before terminating 50 or more employees at a single location within a four-week period.

There have been 114 group layoff notices so far in 2015, impacting a total of 18,006 workers, according to the latest available data.

That compares to 62 notices in all of 2013 and 2014, affecting 11,694 employees.

The province attributes the major swing in mass terminations to the downturn in natural resource prices.

Oil and gas companies and "other manufacturing and service companies related to the sector" account for 78 per cent of the reported layoffs in 2015, according to Alberta Jobs spokeswoman Shirley Lin.