Grade 10 Science - 1st Mid-Quarter Examination Reviewer

A comprehensive set of vocabulary flashcards covering Earth's layers, volcanic activity, earthquake dynamics, and the evolution of tectonic theories based on the Grade 10 Science Reviewer.

Crust

The outermost and thinnest layer of the Earth, consisting of continental crust ($30\text{--}70\,km$ thick) and oceanic crust ($5\text{--}10\,km$ thick).

Granite

The main rock type that composes the continental crust.

Basalt

The main rock type that composes the oceanic crust.

Mantle

The thickest layer of the Earth, approximately $2,900\,km$ thick, composed of silicate rocks rich in magnesium and iron.

Outer Core

A layer composed of liquid iron and nickel that is responsible for generating the Earth's magnetic field.

Inner Core

The hottest layer of the Earth, made of solid iron and nickel due to extremely high pressure.

Lithosphere

The layer consisting of the crust and the uppermost mantle, broken into tectonic plates.

Asthenosphere

The soft, semi-fluid layer beneath the lithosphere that allows tectonic plates to move.

Mesosphere

Technically defined in the text as the boundary between the outer core and the lower mantle.

Magma Chamber

A reservoir that stores molten rock beneath the Earth's surface.

Conduit

The underground passage through which magma travels to the surface.

Dike

A vertical sheet of solidified magma that cuts across rock layers.

Sill

A horizontal sheet of solidified magma between rock layers.

Shield Volcano

A broad volcano with gentle slopes formed by fluid basaltic lava; an example is Mount Apo.

Composite (Stratovolcano)

A tall, steep volcano with alternating layers of lava and ash that produces explosive eruptions, such as Mayon or Pinatubo.

Cinder Cone

A small, steep volcano built from cinders and volcanic fragments, like Smith Volcano.

Lava Dome

A rounded, slow-growing volcanic feature formed from thick, sticky lava.

Plinian Eruption

A very explosive eruption style that produces tall eruption columns.

Phreatic Eruption

A steam-driven explosion where no new magma reaches the surface.

Phreatomagmatic Eruption

An explosion caused by the interaction of magma and water.

Pyroclastic Flow

An extremely hot and fast-moving mixture of ash, rocks, and gases.

Lahar

A volcanic mudflow composed of a mixture of ash, rocks, and water.

Focus (Hypocenter)

The point inside the Earth where an earthquake begins.

Epicenter

The point on the Earth's surface directly above the focus.

P-Waves

The fastest seismic waves that can travel through solids, liquids, and gases.

S-Waves

Seismic waves that are slower than P-waves and can travel only through solids.

Surface Waves

The slowest seismic waves which cause the greatest damage; examples include Love Waves and Rayleigh Waves.

Magnitude

The measure of the amount of energy released during an earthquake.

Normal Fault

A fault caused by tension where the hanging wall moves downward relative to the footwall.

Reverse Fault

A fault caused by compression where the hanging wall moves upward relative to the footwall.

Strike-Slip Fault

A fault caused by horizontal movement, categorized as right-lateral (dextral) or left-lateral (sinistral).

Triangulation Method

A method used to locate an earthquake epicenter using data from three seismic stations.

Ridge Push

A cause of plate movement where new crust formed at mid-ocean ridges pushes older crust away.

Slab Pull

A cause of plate movement where dense oceanic crust sinks into the mantle, pulling the rest of the plate.

Divergent Boundary

A plate boundary where plates move apart, producing rift valleys and mid-ocean ridges.

Convergent Boundary

A plate boundary where plates move toward each other, producing volcanoes, mountain ranges, and ocean trenches.

Transform Boundary

A plate boundary where plates slide past each other, producing faults and earthquakes like the San Andreas Fault.

Continental Drift Theory

The theory proposed by Alfred Wegener in 1912 suggesting all continents were once joined as Pangaea.

Seafloor Spreading Theory

The theory proposed by Harry Hess in 1962 stating new oceanic crust forms at mid-ocean ridges and older crust is recycled by subduction.

Glonar Challenger

The vessel that sent a $6\,km$ pipe to the ocean floor to collect drilling samples to support seafloor spreading.

Magnetic Stripes

Alternating bands of magnetic polarity on both sides of mid-ocean ridges used as evidence for seafloor spreading.

Plate Tectonic Theory

A unifying theory developed by several scientists that combines Continental Drift and Seafloor Spreading.