30 min interview at a conference. Recruiter told me immediately that I made it to the 2nd round. They flew me to TX two weeks after that for a group interview. Interview atmosphere was very laid back and relaxing. They gave presentations on the different company segments, spoke about their experiences so far, then I gave a group presentation on topics they had given us the week before. The whole thing started a 6pm and ended at 3am. Next day we were up at 7am for breakfast and drove to a site at 8am. Then lunch, then a 10 min exit interview. After the exit interviews we went for dinner at a steakhouse, recruiters drank a bit too much...to the point that I thought "Are they serious". I encourage you to be honest about your interest in SLB, ask questions, and try to get all recruiters to notice you.

1st round interview included short technical question, and telling about myself and the projects I worked on. Not difficult/or hard, but just need to explain well enough to tell the logic process