ASBOG ASBOG - Association of State Boards of Geology Geochemistry and Soil Science Questions and Answers 1

Question 1

Which element is the most abundant by weight in the Earth's crust?

Accepted Answer

Oxygen

Answer

Oxygen is the most abundant element in Earth's crust, comprising approximately 46% by weight.

Question 2

Eh-pH (Pourbaix) diagrams are used in geochemistry to display the stability fields of what?

Accepted Answer

Minerals and aqueous species

Answer

Eh-pH diagrams display the thermodynamic stability fields of minerals and dissolved species as a function of redox potential and acidity.

Question 3

Which soil horizon is characterized by the accumulation of illuviated clay, iron oxides, and aluminum?

Accepted Answer

B horizon

Answer

The B horizon is the zone of illuviation where materials leached from overlying horizons accumulate, including clay, iron oxides, and aluminum compounds.

Question 4

What does CEC stand for in soil science?

Accepted Answer

Cation Exchange Capacity

Answer

Cation Exchange Capacity (CEC) measures the total capacity of a soil to hold exchangeable cations and is a key indicator of soil fertility and contaminant retention.

Question 5

Acid mine drainage (AMD) is primarily generated by the oxidation of which mineral?

Accepted Answer

Pyrite

Answer

Pyrite (FeS₂) oxidizes when exposed to water and oxygen, generating sulfuric acid that dramatically lowers pH and mobilizes heavy metals into drainage water.

ASBOG - Association of State Boards of Geology Practice Test

ASBOG - Association of State Boards of Geology Practice Test

ASBOG ASBOG - Association of State Boards of Geology Geochemistry and Soil Science Questions and Answers 1