Earth Science Quiz Regular

Which of the following is an igneous rock?

• Sandstone

• Granite

• Shale

• Limestone

Answer explanation

Granite is an igneous rock formed from the cooling and solidification of magma. In contrast, sandstone, shale, and limestone are sedimentary rocks, which are formed from the accumulation of sediments.

Which rock type is formed from compacted sediments?

• Igneous

• Sedimentary

• Metamorphic

• Fossiliferous

Answer explanation

Sedimentary rocks are formed from the compaction and cementation of sediments. This process involves layers of particles accumulating over time, making sedimentary the correct answer.

Metamorphic rocks form primarily due to:

• Cooling and crystallization

• Weathering and erosion

• Heat and pressure

• Melting

Answer explanation

Metamorphic rocks form primarily due to heat and pressure, which alter existing rocks without melting them. This process changes the mineral composition and structure, distinguishing them from igneous and sedimentary rocks.

Marble is an example of which type of rock?

• Igneous

• Sedimentary

• Metamorphic

• Fossiliferous

Answer explanation

Marble is a metamorphic rock formed from limestone under heat and pressure. It is not igneous or sedimentary, and fossiliferous refers to rocks containing fossils, which does not apply to marble.

Which is the correct order of Earth's layers from outermost to innermost?

• Mantle → Crust → Outer core → Inner core

• Crust → Mantle → Outer core → Inner core

• Crust → Outer core → Mantle → Inner core

• Mantle → Crust → Inner core → Outer core

Answer explanation

The correct order of Earth's layers from outermost to innermost is Crust → Mantle → Outer core → Inner core. This sequence reflects the structure of the Earth, with the crust being the outermost layer.

The Earth's lithosphere is made up of:

• Crust only

• Mantle only

• Crust and uppermost mantle

• Core and mantle

Answer explanation

The Earth's lithosphere consists of the crust and the uppermost part of the mantle. This rigid layer is crucial for tectonic activity, making 'Crust and uppermost mantle' the correct choice.

Which layer of Earth is liquid and responsible for Earth's magnetic field?

• Crust

• Mantle

• Outer core

• Inner core

Answer explanation

The outer core is the only liquid layer of Earth, composed mainly of molten iron and nickel. Its movement generates electric currents, which produce Earth's magnetic field.

What type of plate boundary occurs when two plates move apart?

• Convergent

• Divergent

• Transform

• Subduction

Answer explanation

A divergent plate boundary occurs when two tectonic plates move apart, allowing magma to rise and create new crust. This is in contrast to convergent boundaries where plates collide, and transform boundaries where plates slide past each other.

The asthenosphere is described as "plastic" because:

• It is completely solid and rigid

• It can flow slowly like a thick liquid under pressure

• It is made of molten magma only

• It is part of the outer core

Answer explanation

The asthenosphere is described as "plastic" because it can flow slowly like a thick liquid under pressure, allowing tectonic plates to move. This distinguishes it from being completely solid or made of molten magma.

As you go deeper into Earth, which of the following increases?

• Temperature and pressure

• Volume and density

• Fossil content

• Plate movement speed

Answer explanation

As you go deeper into Earth, both temperature and pressure increase due to the weight of the overlying material and geothermal gradients. This makes 'Temperature and pressure' the correct choice.