Geologic Time Scale and Fossils

How long has life existed on Earth?

• About 1 billion years

• About 2.5 billion years

• About 4 billion years

• About 541 million years

What is the scientific study of interpreting layers of rock in Earth's outer surface called?

• Paleontology

• Stratigraphy

• Archaeology

• Meteorology

Which principle states that in undisturbed rock layers, the layers closer to the surface are younger than the layers below them?

• Principle of Superposition

• Law of Faunal Succession

• Principle of Original Horizontality

• Law of Cross-Cutting Relationships

What was the key to William Smith's method for comparing the ages of rock formations from different locations?

• Analyzing the chemical composition of the rocks.

• Measuring the thickness of the rock layers.

• Comparing the fossils found within the rock layers.

• Observing the color variations in the rock strata.

What is the largest division of time in the Geologic Time Scale?

• Era

• Period

• Eon

• Epoch

Which eon is characterized by Earth being a searing wasteland with volcanic activity, cosmic bombardments, and no fossil evidence of life?

• Archean Eon

• Proterozoic Eon

• Phanerozoic Eon

• Hadean Eon

What type of organisms flourished during the Archean Eon, forming mats of microbes in the primordial seas?

• Dinosaurs

• Stromatolites

• Trilobites

• Eukaryotes

What significant event occurred during the Proterozoic Eon that led to a major change in Earth's atmosphere and paved the way for new life forms?

• The formation of the first continents.

• The appearance of photosynthetic bacteria releasing oxygen.

• A massive asteroid impact.

• The cooling and solidification of Earth's crust.

What major event marked the beginning of the diversification of visible life in the world's oceans?

• The formation of Pangaea

• The Cambrian Explosion

• The Great Dying

• The first Ice Age

Which of these geological time periods is NOT part of the Precambrian Eon?

• Hadean Eon

• Archean Eon

• Proterozoic Eon

• Paleozoic Era