What type of rock is formed from the remains of living organisms?
A Igneous
B Sedimentary
C Volcanic
D Metamorphic
Sedimentary rocks form from the compaction of sediments, which often include remains of plants and animals. These rocks, such as limestone, often contain fossils. Igneous rocks form from cooling magma, while metamorphic rocks result from heat and pressure.
Which of the following is a characteristic of clay soil?
A Drains quickly
B Large particle size
C Poor load-bearing capacity
D Easily compacts
Clay soil has small, fine particles that compact easily, reducing its permeability and making it less suitable for construction without proper treatment. It retains water and does not drain well. It also has a relatively high load-bearing capacity compared to sandy soils.
Which of the following minerals is commonly found in granite?
A Feldspar
B Calcite
C Gypsum
D Halite
Feldspar is a primary mineral in granite, an igneous rock. It forms the largest component of granite along with quartz and mica. Calcite and gypsum are sedimentary minerals, while halite is associated with evaporite deposits.
What is the key characteristic of fault zones?
A Stable and unchanging
B Areas of high mineral content
C They are areas of significant movement
D They contain fossils
Fault zones are regions where tectonic plates or rock masses have experienced significant movement due to tectonic forces. These movements can lead to earthquakes, and the areas often contain fractures in the Earth’s crust. They do not necessarily contain fossils or minerals.
Which type of seismic wave travels the fastest?
A Surface waves
B S-waves
C P-waves
D Rayleigh waves
P-waves (primary waves) are the fastest type of seismic wave and can travel through both solid and liquid. They are the first to be detected by seismographs. S-waves are slower and can only travel through solids, while surface waves are the slowest and cause more surface damage.
What is the role of a geophysical survey in site investigation?
A To map subsurface conditions
B To measure soil moisture
C To identify seismic activity
D To assess air quality
A geophysical survey is used to map subsurface conditions without drilling. It employs techniques like seismic reflection, electrical resistivity, and ground-penetrating radar to detect soil properties, rock formations, and groundwater levels. It helps in understanding the geological conditions before construction.
What is the purpose of core sampling in geotechnical investigation?
A To study rock texture
B To collect soil for analysis
C To determine groundwater flow
D All of above
Core sampling involves extracting cylindrical samples of soil or rock from the ground to analyze their physical properties, such as strength, moisture content, and mineral composition. This process helps in determining the suitability of soil or rock for construction projects.
Which process leads to the formation of igneous rocks?
A Deposition
B Cooling of magma
C Pressure and heat
D Compaction of sediments
Igneous rocks form when magma or lava cools and solidifies. The process of cooling leads to the formation of different textures depending on the rate of cooling. Metamorphic rocks form under pressure and heat, while sedimentary rocks form through deposition and compaction.
What is the role of stratigraphy in geology?
A To study earthquakes
B To measure groundwater levels
C To analyze the layers of rock
D To map tectonic plate movements
Stratigraphy is the branch of geology that focuses on the study of rock layers (strata). It helps geologists understand the sequence of geological events and the history of the Earth’s surface. Stratigraphy is crucial in dating rocks and understanding geological time.
What is the primary characteristic of metamorphic rocks?
A Formed under heat and pressure
B Contain fossils
C Formed from cooling lava
D Made of layered sediments
Metamorphic rocks are formed when existing rocks are subjected to heat and pressure, which causes changes in their mineral composition and structure. Common examples include marble (from limestone) and slate (from shale). These rocks do not form from cooling lava.
Which type of rock is most likely to contain fossils?
A Igneous
B Volcanic
C Metamorphic
D Sedimentary
Sedimentary rocks are most likely to contain fossils because they form from the accumulation of sediments, including organic material. These rocks often trap and preserve plant and animal remains. Igneous and metamorphic rocks are formed under different conditions and typically do not contain fossils.
What is the effect of weathering on rocks?
A Hardens rocks
B Creates new minerals
C Breaks rocks into smaller pieces
D Increases rock density
Weathering is the natural process that breaks down rocks into smaller particles. This can be physical (like freeze-thaw cycles), chemical (like oxidation), or biological (like plant root expansion). The process weakens rocks and leads to their fragmentation.
What is a common geotechnical test for determining soil compaction?
A Sieve analysis
B Proctor test
C X-ray diffraction
D Tensiometer test
The Proctor test is a common method used to determine the compaction characteristics of soil. It helps engineers understand the optimal moisture content at which soil achieves maximum density. Sieve analysis is used for particle size distribution, and X-ray diffraction analyzes minerals.
What does the term “aquifer” refer to in geology?
A A layer of rock that stores groundwater
B A mineral deposit
C A type of soil
D A volcanic eruption
An aquifer is a layer of rock or sediment that can store and transmit groundwater. It acts as a natural reservoir for water that can be extracted for use in irrigation, drinking, and industrial applications. Aquifers are typically found in porous rock formations.
What is the primary cause of slope instability in hilly areas?
A Fault lines
B Soil compaction
C Water infiltration
D Volcanic activity
Water infiltration is a primary cause of slope instability in hilly areas, as it adds weight and reduces the friction between soil particles, making the slope more prone to landslides. Fault lines and volcanic activity can also affect stability, but water infiltration is the most common factor.