North Carolina General Contractors Practice Exam

What type of rock is the easiest to excavate or rip?

1. Igneous Rock

2. Metamorphic Rock

3. Sedimentary Rock

4. Basalt Rock

The correct answer is: Sedimentary Rock

Sedimentary rock is generally the easiest type of rock to excavate or rip due to its formation process and physical characteristics. These rocks, which include formations like sandstone, limestone, and shale, are typically softer and less dense than igneous or metamorphic rocks. As a result, they tend to have a lower compressive strength, making them more amenable to excavation with standard construction machinery. Sedimentary rock is formed from the accumulation of sediments over time, which can include fragments of other rocks, minerals, and organic matter. This process often results in a layered structure that can create weaknesses along the layers, making them easier to break apart. In contrast, igneous rocks form through the solidification of molten material and usually exhibit a much more robust and dense structure, which can require more intensive drilling or blasting procedures to excavate. Metamorphic rocks, formed under high pressure and temperature conditions, also present a challenge due to their often interlocking crystal structures, making them harder and more resistant to excavation. Basalt rock, while technically classified as an igneous rock, is also dense and hard, requiring similar excavation methods as other igneous varieties. Thus, sedimentary rock stands out as the most favorable for excavation tasks in