Although the Origin Is Unclear, Most Cratons of the World

question 1

Multiple Choice

Although the origin is unclear, most cratons of the world experienced major episodes of metamorphism between about __________ billion years ago.

• A) 1.3 and 2.3
• B) 2.3 and 2.7
• C) 2.7 and 3.3
• D) 3.3 and 3.5

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Definitions:

Chemical Equation

A symbolic representation of a chemical reaction, with reactants on the left, products on the right, and an arrow indicating the direction of the reaction.

Iron

A strong, hard magnetic silvery-grey metal, very abundant in the earth's crust and the core element of hemoglobin in blood.

Pyrolysis

A thermochemical decomposition of organic material at elevated temperatures in the absence of oxygen.

Combustion

A chemical process involving the rapid combination of a substance with oxygen to produce heat and light, often resulting in fire or explosion.