WeeklyInvestment pours in to Vaca MuertaChevron, ExxonMobil, Shell, Total and Schlumberger have joined Argentinian players Tecpetrol, Pluspetrol and state-controlled YPF in the prolific regionRoom for all: a Vaca Muerta shale rig site in the Patagonian province of Neuquen, ArgentinaGareth ChetwyndRio de Janeiro