They asked the basic questions: "Why are you interested in Schlumberger?" "Talk about your past experiences". Although I did only interview for an internship they made the process very easy.

I applied through campus and was given an in person interview, it was a general HR interview, more like they wanted to get to know you. Then was offered a second round where they reserved a hotel for you and invited all the candidates for dinner to meet the interviewers. the next day was reserved for interviews, each person had two interviews.