Exam 8: Precambrian Earth and Life History the Hadean and the Archean Eon

The high Earth temperatures in the Archean probably played a role in the rapid rate of plate motion.

Areas of buried shield rock with younger sedimentary cover are known as ____________________.

Explain why Mercury, Venus, and Mars lack plate tectonics.

Komatiites are common from the Archean eon, although none are produced in modern tectonic environments.

What is one characteristic of Archean rocks?

Geologists believe that ____________________ are the remains of reef structures from one of the first photosynthesizing organisms.

Which event did not occur in the Hadean (4.6-4.0 bya)?

Describe and discuss the early atmosphere of Earth. What was its most likely composition? How was it different from the present atmosphere and why?

Discuss the characteristics and formation of greenstone belts. Why are these rocks important in explaining early Earth history?

Submarine hydrothermal vents commonly are found near mid-oceanic ridges where seafloor spreading occurs.