Question

Aquifers composed primarily of loose sand and gravel materials are classified as

• A. Consolidated formations
• B. Unconsolidated formations
• C. Igneous rocks
• D. Metamorphic rocks

Hint:

Aquifers: \[ \boxed{ \begin{aligned} \text{Sand \& Gravel} &\rightarrow \text{Unconsolidated aquifer}\\ \text{Sandstone/Limestone} &\rightarrow \text{Consolidated aquifer} \end{aligned} } \]

Answer 1

The Correct Option is B

Step 1: Recall the two broad classes of water-bearing material.
Geological formations are grouped as consolidated (cemented, hard rock) or unconsolidated (loose grains not stuck together).
Step 2: Apply this to sand and gravel.
Loose sand and gravel grains simply sit next to each other without any cementing material binding them, which is the definition of an unconsolidated formation.
Step 3: Rule out the rock options.
Igneous and metamorphic rocks are hard, cemented rock types, and consolidated formations are also cemented, so none of these describe loose sand and gravel.
\[ \boxed{\text{Unconsolidated formations}} \]