What is petroleum?
a) Gas hydrates of methane and carbon dioxide
b) Minerals deposited from biogenous secretions
c) Oil and natural gas formed from remains of ancient microorganisms buried within marine sediments
d) A combination of siliceous and calcium carbonate oozes that decompose
Question 2
What is the significance of stromatolites?
a) They are composed of benthic patches of bacteria found at hydrothermal vents.
b) Cyanobacteria produce carbonate structures in warm shallow seas that can date back to 3 billion years ago.
c) They are composed of siliceous deposits of diatoms and dinoflagellates.
d) They are composed of biogenous deposits of foraminiferans and coccolithophores.