What type of weathering involves the breakdown of rocks through chemical reactions?
A Chemical weathering
B Physical weathering
C Biological weathering
D Erosion
Chemical weathering occurs when rocks undergo chemical reactions, often with water, oxygen, or acids, leading to the breakdown of minerals within the rocks. This process can alter the composition of the rock, unlike physical weathering, which only breaks the rocks into smaller pieces.
What is the primary cause of erosion in coastal areas?
A Wind
B Ice
C Water
D Biological factors
Water is the primary cause of erosion in coastal areas. Wave action, tides, and currents gradually wear away rock and sediment along shorelines, shaping coastal features like cliffs and beaches. Wind and ice contribute to erosion but are less significant in coastal regions.
What is the main purpose of a geotechnical investigation?
A To study weather patterns
B To assess subsurface conditions
C To measure air quality
D To predict earthquakes
A geotechnical investigation is conducted to evaluate subsurface conditions, including soil composition, strength, and groundwater levels. This information is vital for designing safe and stable foundations for construction projects. It helps determine the suitability of the ground for various structures.
What is the term used for the movement of soil down a slope due to gravity?
A Landslide
B Erosion
C Deposition
D Seismic activity
A landslide is the downward movement of soil and rock caused by gravity, often triggered by factors like heavy rainfall, earthquakes, or volcanic activity. Erosion and deposition involve the removal and settling of materials but are not typically associated with sudden movements like landslides.
What is the main cause of slope instability?
A Low moisture content
B High vegetation cover
C Excessive water infiltration
D Low mineral content
Excessive water infiltration is a major cause of slope instability as it weakens the soil and reduces friction between particles. This can cause landslides, particularly in areas with steep slopes. High vegetation cover generally stabilizes slopes, and low moisture content helps maintain stability.
Which of the following is commonly used to obtain samples of rock or soil for testing?
A Seismograph
B Geophone
C Magnetometer
D Borehole
A borehole is drilled into the ground to obtain rock or soil samples for geotechnical testing. These samples are analyzed to assess subsurface conditions and are essential for determining soil properties and making decisions about construction. Seismographs and geophones measure seismic activity.
What is the term for the deposition of materials carried by wind?
A Aeolian deposition
B Glacial deposition
C Fluvial deposition
D Marine deposition
Aeolian deposition refers to the deposition of materials carried by wind. This process is common in desert regions, where sand and dust are transported by wind and create features like dunes. Glacial, fluvial, and marine deposition are related to ice, water, and ocean processes.
Which of the following can cause landslides?
A Strong winds
B Earthquakes
C High temperatures
D Excessive plant growth
Earthquakes can trigger landslides by shaking the ground and causing unstable slopes to collapse. While strong winds and high temperatures can contribute to erosion, they do not directly cause landslides. Excessive plant growth usually helps stabilize slopes.
What type of rock is typically used for tunnel construction?
A Limestone
B Sandstone
C Granite
D Shale
Granite is commonly used in tunnel construction due to its strength and durability. It can withstand high pressures and is less likely to erode or collapse over time. Limestone, sandstone, and shale are less ideal due to their tendency to weather and weaken more easily.
What is the term used for the process of rock formation from accumulated sediment?
A Metamorphism
B Lithification
C Crystallization
D Erosion
Lithification is the process by which accumulated sediments are compacted and cemented together to form sedimentary rocks. This process occurs over time as pressure builds up, turning loose sediments into solid rock. Metamorphism involves heat and pressure altering existing rocks.
What geological hazard is associated with volcanic activity?
A Lava flows
B Earthquakes
C Tsunamis
D Sinkholes
Lava flows are a common geological hazard associated with volcanic activity. When a volcano erupts, molten rock (lava) can flow down the sides, destroying anything in its path. Earthquakes and tsunamis can also be triggered by volcanic activity, but lava flows are the direct result.
What is the process of water seeping through the soil called?
A Erosion
B Percolation
C Evaporation
D Infiltration
Infiltration is the process by which water enters the soil and moves through the pores between soil particles. This process is crucial for replenishing groundwater supplies. Percolation refers to the downward movement of water through the soil layers, which follows infiltration.
What is the primary factor influencing the engineering properties of rocks?
A Color
B Texture
C Mineral composition
D Weight
The mineral composition of rocks plays the largest role in determining their engineering properties such as strength, durability, and stability. Rocks with hard minerals like quartz tend to have higher strength. Texture, color, and weight are secondary factors.
What is the term for a type of rock that has undergone significant changes due to heat and pressure?
A Igneous
B Metamorphic
C Sedimentary
D Volcanic
Metamorphic rocks are formed when existing rocks (either igneous or sedimentary) undergo significant changes due to heat and pressure. This process alters the rock’s mineral structure. Common examples include marble (from limestone) and slate (from shale).
Which type of soil is most prone to compaction?
A Clay
B Gravel
C Sand
D Loam
Clay is the most prone to compaction because its fine particles can easily pack together, reducing pore space and increasing density. This makes it harder for water to flow through, while gravel and sand are less prone to compaction and allow better drainage.