Oliver struck for a pair of goals as the Newfoundland and Labrador girls defeated New Brunswick 3-0.
Melissa Bazan also scored for the provincial girls in the win.
Bazan opened the scoring in the 27th minute, which was the only goal of the first half.
Oliver went rapid-fire with her two markers, bulging the mesh in the 63rd and 70th minutes.
In the other girls game, Nova Scotia blanked Prince Edward Island 6-0.
Helen Opitz (2), Adrianna Timmons, Allyson Wilton, Alli Kelly and Hannah Lewis did the damage for the winning side.
In action from the boys division, Newfoundland and Labrador were downed 3-1 by New Brunswick.
Harrison McGinn, Jun Lin and Daniel Keripe got on the scoreboard for the victors.
Colin Connors was the lone marksman for the host club.
Later, the Nova Scotia boys edged P.E.I. 1-0 thanks to a goal from Calum Anthony.
Tournament action continues today.