Olson, 27, tallied 17 goals and 27 assists for 44 points in 75 AHL games with Abbotsford last season, and added one goal in four Calder Cup Playoff matches.
In two pro seasons, Olson has totaled 25 goals and 37 assists for 62 points in 145 AHL contests.
The Superior, Wis., native played four seasons (2008-12) at Michigan Tech, where he served as team captain for his senior season (2011-12) and twice earned WCHA All-Academic Team honors.
Zanon, 34, appeared in 24 AHL games with the Rampage in 2013-14, recording four assists. He has appeared in 493 career National Hockey League games for Nashville, Minnesota, Boston and Colorado, registering 12 goals and 50 assists for 62 points.
The Burnaby, B.C., native won the Calder Cup with Milwaukee in 2004, and returned to the Finals with the Admirals in 2006. He played four seasons (1999-2003) for the University of Nebraska-Omaha and was drafted by Ottawa in the fifth round in 2000.