Review of Earth History

Review of Earth History

Multiple Choice

Based on current scientific evidence, how old is the Earth?

• 6,000 years old

• 460 million years old

• 4.6 billion years old

• 46 billion years old

Evidence

How does scientists know the age of Earth?

Multiple Choice

When an unstable element like uranium turns into a more stable element like thorium, it is called:

• plate drifting.

• transformation.

• a chemical reaction.

• radioactive decay.

Multiple Choice

The amount of time it takes for 50% of a sample of a radioactive element to decay is called its:

• decay rate.

• half-life.

• half-blood.

• lifespan.

Multiple Choice

The geological time scale is divided into units of time scale. Which is the correct order in descending duration?

• period, era, epoch, eon

• eon, era, period, epoch

• eon, epoch, era, period

• epoch, period, era, eon

First life on Earth

Stromatolites

layered rocks, lithified remnants of microbial communities with or without active microbes

Multiple Choice

What type of fossil is this?

• Mold

• Cast

• Trace

• Preserved

Multiple Choice

What type of fossil is this?

• Mold

• Cast

• Trace

• Preserved

Multiple Choice

Where would paleontologists more likely to find fossils?

• Igneous rocks

• Sedimentary rocks

• Metamorphic rocks

Used along with

• radioisotope dating

• stratigraphy

Oxygenic Earth

Poll

"Appearance of oxygen in the atmosphere". Is this an evidence?

• Yes

• No

Evidence of oxygen in the atmosphere

• Iron ore (Fe_xO_y) in

• Sulfate (SO₄^2-) in ocean sediments

• Cyanobacteria

EVIDENCE

a sign or indication (object, date) to prove that something (an event) is or is not true