Wiebe, from Stittsville, Ont., took the women's 75-kilogram division.
She won all four of her matches, capping her run by defeating Indian wrestler Jyoti by pinfall. She also beat England's Sophie Edwards, Cameroon's Annabel Ali and Nigeria's Blessing Onyebuchi on points.
Jarvis, from Elliot Lake, Ont., won the men's 125-kg class.
He defeated Rajeev Tomar in the final, outscoring the Indian 3-0. Tomar took silver, while England's Chinu Xxx and Nigeria's Sinivie Boltic took bronze.
Also Tuesday, Jasmine Mian of Barrie, Ont., won bronze in the women's 48-kilogram event, defeating Nigeria's Rosemary Nweke 13-2 in a bronze-medal match.
Canadians also won gold medals Tuesday in the women's mountain bike (Catharine Pendrel) and the women's 75-kg weightlifting division (Marie-Ève Beauchemin-Nadeau).