Granite is an igneous rock that forms from the cooling of molten magma beneath the Earth’s surface. It is characterized by its coarse texture and composition of minerals such as quartz, feldspar, and mica. Sandstone and limestone are sedimentary, while marble is metamorphic.
What is the main component of the Earth’s crust?
A Oxygen
B Iron
C Silicon
D Nitrogen
Oxygen is the most abundant element in the Earth’s crust, making up about 46% by weight. It combines with other elements like silicon to form minerals such as silicates, which are predominant in the Earth’s crust. Iron is abundant in the core, not the crust.
What is the primary role of the geotechnical engineer?
A To design buildings
B To study soil and rock properties
C To monitor air quality
D To construct roads
A geotechnical engineer focuses on studying the properties of soil, rock, and other subsurface materials. Their primary role involves determining the suitability of these materials for supporting construction projects, ensuring safety and stability. This involves conducting site investigations and soil tests.
What does a geologist use to measure the age of rocks?
A Seismographs
B Satellites
C Radiometric dating
D Tectonic mapping
Radiometric dating is a method used by geologists to determine the age of rocks by measuring the decay of radioactive isotopes. This technique provides accurate age estimates for rocks and minerals, particularly useful for dating igneous rocks. Other methods like seismographs measure seismic activity, not rock age.
What type of rock forms from the compression of sediments?
A Metamorphic
B Igneous
C Sedimentary
D Volcanic
Sedimentary rocks form from the compaction and cementation of sediments over time. These rocks are often layered and can contain fossils. Common examples include limestone, sandstone, and shale. Metamorphic rocks form under heat and pressure, and igneous rocks form from cooled magma or lava.
What is the term for the movement of water through soil?
A Infiltration
B Erosion
C Stratigraphy
D Lithification
Infiltration refers to the process by which water penetrates and moves through the soil. This process is crucial for replenishing groundwater supplies. Erosion refers to the removal of soil, stratigraphy studies rock layers, and lithification is the process of turning sediments into rock.
What is a fault in geology?
A A type of mineral
B A layer of rock
C A crack in the Earth’s surface
D A type of sediment
A fault is a crack or fracture in the Earth’s surface along which movement has occurred due to tectonic forces. These movements can cause earthquakes. Faults are key to understanding seismic activity and are classified based on their movement direction, such as strike-slip or thrust faults.
What is the primary cause of earthquakes?
A Volcanic eruptions
B Soil erosion
C Heavy rainfall
D Movement along faults
Earthquakes are primarily caused by the sudden movement along faults within the Earth’s crust. These movements release energy in the form of seismic waves. While volcanic eruptions can also trigger earthquakes, faults are the most common source of seismic activity. Soil erosion and rainfall do not directly cause earthquakes.
What is the primary characteristic of metamorphic rocks?
A Formed by cooling of magma
B Formed from high temperature and pressure
C Composed mainly of sand particles
D Layered with fossils
Metamorphic rocks are formed by heat and pressure that alter existing rocks (either igneous or sedimentary) without melting them. Common examples include marble (from limestone) and slate (from shale). These rocks do not form from cooling magma, and while they may have layers, they do not necessarily contain fossils.
What is the purpose of a borehole in geotechnical investigation?
A To collect soil samples
B To measure the temperature
C To extract groundwater
D To detect seismic activity
A borehole is drilled into the ground to collect soil or rock samples for analysis. These samples are then tested to determine properties such as strength, moisture content, and compaction. Boreholes are a vital part of geotechnical investigations, helping engineers assess the suitability of the ground for construction.
What is the primary role of an aquifer?
A To provide minerals
B To filter contaminants
C To store water
D To support plant growth
An aquifer is a geological formation that stores groundwater. It is made up of porous rock or sediment that allows water to flow through it, providing a natural source of freshwater. Aquifers are critical for drinking water, irrigation, and other water needs. They do not directly filter contaminants or support plant growth.
What is the effect of weathering on rocks?
A It makes them harder
B It causes them to break down into smaller pieces
C It changes their chemical composition
D It causes them to become more compact
Weathering is the process that breaks down rocks into smaller particles through physical, chemical, and biological processes. It can cause rocks to disintegrate, change color, or alter chemically. This is different from processes like compaction, which occurs during sedimentary rock formation.
Which rock type is formed from the solidification of magma?
A Shale
B Metamorphic
C Sedimentary
D Igneous
Igneous rocks form from the solidification of magma (if formed beneath the Earth’s surface) or lava (if formed on the surface). These rocks, such as granite and basalt, are classified into intrusive or extrusive depending on where they form. Metamorphic and sedimentary rocks form through different processes.
What is the function of structural geology?
A To study the deformation of rocks
B To analyze Earth’s mineral composition
C To determine the age of rocks
D To predict weather patterns
Structural geology focuses on understanding the deformation of rocks due to tectonic forces. It studies how rocks fold, fracture, and fault under pressure, which helps in understanding earthquake mechanisms and tectonic plate movements. It does not directly deal with the mineral composition or age of rocks.
What is the main purpose of conducting a geophysical survey?
A To analyze soil pH
B To detect seismic waves
C To explore subsurface features
D To predict weather changes
A geophysical survey is conducted to explore subsurface features without the need for drilling. It uses methods like seismic reflection, electrical resistivity, and ground-penetrating radar to study the properties and conditions of the ground. These surveys help in site investigations for construction, mining, and environmental studies.