3. PetroAmerica Oil (TSXV:PTA); current price: $0.35; year-to-date gain: 238.10 percent; 52-week high: $0.37.PetroAmerica is a junior oil and gas exploration company with a large portfolio of prospective oil properties in the Llanos Basin in Colombia. On December 17, the company announced a material increase to the reserves at the Las Maracas field. The company had previous announced a new discovery at Las Maracas-3 in July, when it tested 30-degree API oil at a rate of 1,491 barrels of oil per day (bopd). Las Maracas reached production of 6,850 bopd on December 3 when Las Maracas-5 was brought on stream. The company is continuing with its drilling and testing at La Casona-1, where in November the company discovered light oil. 4. Wellstar Energy (TSXV:WSE.H); current price: $0.15; year-to-date gain: 211.11 percent; 52-week high: $0.19. Wellstar Energy is a Canada-based junior oil and gas exploration company. The company signed up for a purchase and sale agreement with a private Colorado company and aims to acquire oil and gas assets in North Dakota. Wellstar announced on December 17 that it is set to acquire $51.5 million worth of North Dakota Bakken oil assets. The acquisition includes a 40-percent joint venture on approximately 18,000 contiguous acres of land. 5. Primeline Energy Holdings (TSXV:PEH); current price: $0.57; year-to-date gain: 171.43 percent; 52-week high: $0.84. Primeline Energy is an oil and gas exploration company that is focused on upstream opportunities in China. Though still at an early stage, the company aims to become a major supplier of oil and gas to the East Chinese market. Share prices for Primeline started climbing in June when the company received approval for its environmental impact assessment for the LS36-1 gas field from the State Oceanic Administration. The company is now waiting on final approval from the Overall Development Commission of the Chinese Central Government.