BUENOS AIRES, Jan 17 (Reuters) - Mexico-based Oil company Vista Oil & Gas (VISTAA.MX)on Monday said it was buying 50% of German unlisted oil and gas company Wintershall Dea"s stake in two concessions in Argentina"s Vaca Muerta shale oil deposit. The price of the transaction was agreed at $140 million, including the anullment of a $77 million upfront payment made by Vista in September. Wintershall, which said it was focusing on its Argentine gas production, separately announced that it was closing all of its Brazil operations. Vista Chief Executive Miguel Galuccio said the acquisition of the areas called "Aguada Federal" and "Bandurria Norte" would allow the company to expand its leadership in Vaca Muerta and redouble its commitment to the shale region"s development. Vista recently said that it will invest $2.3 billion from 2022 to 2026 in to double its production and increase its exports from Vaca Muerta. Vista, Argentina"s second biggest shale oil operator, acquired 25,231 net acres in the deal, increasing its total acreage in Vaca Muerta to 183,084 acres. In addition, it added up to 150 new wells to its portfolio in the formation, bringing its total to 850. The company plans to reach a production of more than 80,000 barrels of oil equivalent per day in 2026 and export 60% of all its production, from the 30% it currently exports. Vaca Muerta is estimated to be the world"s fourth largest shale oil reserve and second-biggest shale gas deposit.