I'm from Pakistan where we have two two types of undergraduate degrees i.e. BS(4 year) and BSc(3 years + 1 additional year), its a stupid thing on part of the universities but anyways, BS students here are compelled to take additional subjects for e.g. Communication Skills,Functional Biology,Computer Applications etc( these subjects may seem interesting and worth taking but they aren't, they're more or less the same things one learns in middle and high school) and in the BSc system students apart from Geology subjects study just mandatory subjects like Calculus,Physics etc. So I'm changing over to the MSc system. My question is that will my decision not to take those classes result in me having to take extra classes when I go abroad for higher education(US/Canada)?
Its no different here in the states. The Deans of the various schools collude to get students from other departments to take classes in their departments in the guise of helping the students get a more well rounded education. I taught a class called Geology for Engineers, basically Physical Geology for Civil Engineers with an emphasis on engineering disasters caused by the ignorance of engineers of geological principles and processes.
To answer your question, yes. To get into a MS program you need to pass the Graduate Record Exam. It covers various things, and most BS programs in the states for geology, require a semester of calculus and a year of physics, some computere science etc. Today, geologists are required to be more quantitative. Software runs the oil and gas exploration process, so computer science is also a good class to have. If your school does no have one of the top three geology and geophysics software packages, Kingdom/Petra, Petrel, or Landmark, ask them why? They are free to universities. All they have to do is apply for them. Coming out of school, having knowledge of them is a big plus in finding a job. I think some schools do not want them because the professors do not want to have to learn them. Students benefit a lot by having them and learning to use them, even if it is on their own time. My alma mater refused an offer I made to give the Kingdom. The professors who I knew, did so for ego reasons, not the best interests of the students.