Since I was abroad during the interview process, it took me about 10-12 hours overall. This is because you have to do a lot of activities for the application, such as role plays and presentations. First there were normal interviews about myself, and what I do. Then there was a technical interview about petrophysics itself. After that you get to do the numerical exam, the logical exam. Also one true/false exam where you get to read about 3 pages of data and answer questions on it. After that you get to do a role play. (Very difficult). You get about 15-20 pages of data, and only 30 minutes to read it. I did mine on the computer on skype with the interviewer which was very difficult because I could not make any marks. Then, after reading all the information, you have to protect your view on a certain position (in my case I had to prove to my manager that her technology was too old and needed changing). After you do that, you get another massive document (30 pages) to go through and make a presentation on how you think you could improve.