Most of the petroleum found in the Persian Gulf area formed at a ...

[folubunmi]

Most of the petroleum found in the Persian Gulf area formed at a ___________________ _ continental
  margin where the remains of ___________________ _ were buried and converted to petroleum. Fill in the blank(s) with the appropriate word(s).

Question 2

The heat that drives thermal convection cells comes primarily from ___________________ _ and is
  supplemented by ___________________ _. Fill in the blank(s) with the appropriate word(s).

[perkiness]

Answer to Question 1

passive, microorganims

Answer to Question 2

the core, radioactive decay

[folubunmi]

Great answer, keep it coming

[Joy Chen]

Excellent