Oil and gas industry was one of the earliest adopters of data science. However it wasn’t known as data science back then. Exploration of oil was and is heavily based on Bayesian Statistics, which is more or less a pillar of data science. I’ve worked for an oil and gas analytics company, as one of the answer mentions below BHP Biliton was one of our clients. Every E&P company is adopting data science for optimizing drilling operations, equipment selection, crew selection, production optimization, storage optimization. Couple of examples of the top of my head and in my own language are given below, please know that I’ve worked in drilling optimization hence most of the topics below are related to drilling.