Total, BP unit, YPF announce $1.15 bln investment in Argentina

BUENOS AIRES, July 18 (Reuters) - Argentina's state-run oil firm YPF SA, France's Total, Wintershall Energía SA and BP unit Pan American Energy LLC announced on Tuesday a $1.15 billion joint investment to increase shale gas production. (Reporting by Eliana Raszewski; Writing by Caroline Stauffer and Luc Cohen; Editing by Jonathan Oatis)