What is the procedure with regard to unfinished thesis if I am terminated from the program?
Departments generally do not terminate PhD students without letting the student's advisor know in advance. The fact that your advisor has not responded to you for 3 weeks, suggests the possibility that he/she is ignoring you. This is reasonable behaviour, if in fact your advisor was behind your termination.

As you are not currently in the US, you need to call your department chair and/or the chair of graduate studies and figure out what is going on. In my opinion, it is too soon to look for a new program or to start really worrying about your data.