The '70s is easily my favorite decade for film, so I am not going to even attempt to list just 10 films:
1970
Colossus: The Forbin Project
Little Fauss and Big Halsy
1971
The Andromeda Strain
Carnal Knowledge
Klute
1972
The Candidate
The Mechanic
Silent Running
Slaughterhouse-Five
1973
Bang...