Earth's History

What is unique about the K-T boundary?

• The color it has
• It's enormous width
• The position in the sediments
• Its high concentration of Iridium

Where did the Iridium in K-T boundary come from ?

• The explosion of a Supernova
• An asteroid that crashed into the Earth
• The Sun
• The vulcanism that occurred during Carboniferous

why was it important to find a huge crater for Alvarez's investigation?

• To find the Iridium
• To prove the impact of a huge asteroid
• To prove the extinction of dinosaurs
• To find the fossil of the oldest dinosaur

Why can the K-T boundary be considered  like a "last frontier" for Dinosaurs?

• They loved this layer of clay
• No dinosaur fossils have been found above this layer
• No dinosaur fossils have been found below this layer
• They lived in this layer of clay

What kind of plants resisted the catastrophic impact the best?

• Oaks
• Grass
• Ferns
• All of above

Which layer is oldest?

• A
• W
• G
• Z

Why was shocked quartz a key piece of evidence?

• because we know shocked quartz occurs when explosions (like nuclear bombs) happen, so it meant a large impact occurred

• because quartz is only found on the sea floor so the crater had to be in the water

• because quartz is a rare metal from outer space

• because shocked quartz was not found above the K/T boundary

WHICH GAS IS THE MOST PLENTIFUL IN THE ATMOSPHERE?

• NITROGEN

• OXYGEN

• WATER VAPOUR

• CARBON DIOXIDE

Oxygen is the most common gas in the atmosphere.

• True
• False
• Both True and False
• Neither True nor False

The ozone layer

• is green and purple
• absorbs dangerous solar radiation
• smells like sulphur
• is made of carbon dioxide