First there was an on-campus interview. Following the on-campus interview, I was invited for a group interview in Sugar Land, TX.
The evening before the on-site interview, there was a group dinner. Following dinner, there was an information session and a team-building exercise, where we divided into groups and had to build an "oil rig" using marshmallows and straws.
The following day each candidate gave a 7 minute presentation (previously prepared in Powerpoint) to a group of senior engineers and managers. Following the presentation, we had a series of four short interviews with four different people (senior engineers or managers). Following the interviews, there was a tour of Schlumberger's cable winding facility in Sugar Land. It was an incredibly boring tour, but done because they were unwilling to show us anything interesting that might possibly be confidential.