Chap 1: Rocks and Minerals and their Exploitation Flashcards
Q: What is the Rock Cycle?
A: The Rock Cycle represents the changes between the three rock types (igneous, sedimentary, and metamorphic) and the processes causing these changes.
Q: How are igneous rocks formed?
A: Igneous rocks are formed when liquid magma cools to form solid rock.
Q: What is the difference between magma and lava?
A: Magma is molten rock below the Earth’s surface, while lava is magma that has reached the surface.
Q: What type of igneous rock forms from quick cooling of magma?
A: Extrusive igneous rock forms from quick cooling of magma, resulting in small crystals (e.g., basalt).
Q: What type of igneous rock forms from slow cooling of magma?
A: Intrusive igneous rock forms from slow cooling of magma, resulting in large crystals (e.g., granite).
Q: How are sedimentary rocks formed?
A: Sedimentary rocks are formed by the weathering of existing rocks, accumulation of sediments, and pressurization into layers.
Q: What are some common examples of sedimentary rocks?
A: Limestone, sandstone, and shale are common examples of sedimentary rocks.
Q: How are metamorphic rocks formed?
A: Metamorphic rocks are formed from existing rocks subjected to heat and/or pressure, causing changes without melting the rock.
Q: Name two examples of metamorphic rocks.
A: Marble and slate are examples of metamorphic rocks.
Q: What is prospecting?
A: Prospecting is the process of searching for minerals by examining the surface of rocks.
Q: What is an ore?
A: An ore is a rock containing enough valuable minerals to make it worth mining.
Q: What is remote sensing?
A: Remote sensing involves gathering information about the Earth’s surface from above, such as through aerial photography or satellites.
Q: How does satellite sensing help in mineral exploration?
A: Satellites send signals to the Earth’s surface and collect reflected signals, indicating the presence of minerals. The unique radiation pattern is analyzed by computers.
Q: What is geochemical analysis?
A: Geochemical analysis involves studying the chemical properties of rock samples taken from stream sediments, soil, or rocks.
Q: How does geophysics help in identifying mineral ores?
A: Geophysics uses seismic waves sent through the Earth’s surface to identify mineral ores based on the shock wave patterns reflected by different minerals.
Q: What are the two main methods of mineral extraction?
A: The two main methods are surface mining and sub-surface mining.
Q: What is open-pit mining used for?
A: Open-pit mining is used when a valuable deposit is located near the surface. It involves removing the topsoil and breaking up the rock with explosives.
Q: Describe strip mining.
A: Strip mining involves removing a thin strip of overburden to access a seam of mineral, commonly used for coal and lignite.
Q: What is the process of deep and shaft mining?
A: Deep and shaft mining involves sinking a vertical shaft into the rock layer, creating horizontal tunnels to extract minerals, and bringing the minerals to the surface.
Q: What are some environmental impacts of rock and mineral extraction?
A: Environmental impacts include loss of habitat, pollution (air, water, noise), and visual damage to the landscape.
Q: How does pollution from mining affect aquatic life?
A: Water pollution from mining can lead to the death of aquatic organisms through acidic water and toxic metal ions. Bioaccumulation and biomagnification also impact the food chain.
Q: What are some economic impacts of rock and mineral extraction?
A: Economic impacts include job creation, an increase in the country’s economy, and improvements in infrastructure.
Q: How can mining impact local communities?
A: Mining can improve the standard of living through economic gains but also negatively affect health due to pollution and unsafe conditions.
Q: What is the purpose of land restoration after mining?
A: Land restoration aims to improve soil fertility, reintroduce vegetation, and restore ecosystems.