Earth Structure, Landforms, Volcanoes, and Synoptic Weather

Vocabulary flashcards covering the Earth's interior layers, folding and faulting landforms, volcano classification and structures, and synoptic weather map elements.

Continental Crust

The outermost layer of solid rock on which we live, measuring $6-90\,\text{km}$ thick, thicker under the continents and thinner under the oceans, broken into plates that float on the mantle.

Mantle

The layer beneath the crust that is $2\,900\,\text{km}$ thick, consisting of hot, plastic rock with temperatures that may reach up to $5\,000^\circ\text{C}$.

Outer Core

A very dense but liquid layer due to extremely high temperatures, $2\,250\,\text{km}$ thick, consisting of nickel ($\text{Ni}$) and iron ($\text{Fe}$) known as NiFe.

Inner Core

An extremely hot layer that is solid because of extreme pressure, measuring $1\,200\,\text{km}$ thick.

Moho

The boundary that separates the crust from the mantle.

Plates

Smaller segments of the Earth's crust that float on the mantle.

Fold Mountains

Rocky outcrops, hills, mountains, and entire mountain ranges formed at colliding, compressing boundaries where rocks and debris are warped and folded.

Symmetrical Fold

A fold formed as a result of equal pressure from both sides.

Asymmetrical Fold

A fold formed when pressure is greater from one side, causing the fold to lean to one side.

Over Fold

A fold formed when pressure is even greater on one side, resulting in one limb becoming very steep.

Over Thrust

A geological structure formed when pressure from one side results in a break in the Earth's crust.

Anticline

An upfold or arch-like structure of folded rock layers.

Syncline

A downfold or trough-like structure of folded rock layers.

Extrusive Volcano

A volcano formed when magma pours onto the Earth's surface as lava.

Intrusive Volcano

A volcanic feature formed when magma cools and solidifies within the Earth's crust.

Active Volcano

A volcano that erupts regularly.

Dormant Volcano

A volcano that is not currently erupting but is still capable of erupting.

Extinct Volcano

A volcano that has not erupted in recorded history.

Shield Volcano

A wide volcano with gentle slopes that forms volcanic islands, characterized by low viscosity lava that flows slow and far before it hardens to form a shield-like mound.

Composite Volcano / Stratovolcano

A tall, steep-sided, explosive volcano with a small crater and alternating layers of lava and ash, where highly viscous lava does not flow far before it hardens.

Cinder Cone Volcano

A steep-sided volcano smaller than a stratovolcano, with a large, bowl-shaped crater and mainly rock and ash deposits with less lava flow.

Magma Chamber

A chamber with liquid minerals located $100-200\,\text{km}$ below the surface of the Earth.

Lava Bombs

Chunks of lava thrown into the air during an eruption that cool quickly.

Eruption Cloud

A mixture of gas (carbon monoxide, sulphuric acid), ash, and rock fragments expelled during a volcanic eruption.

Pipe (Volcanic Neck)

The path taken by liquid minerals from the magma chamber to the surface of the volcano.

Pyroclastic Flow

Clouds of red-hot liquid ash flows that move down the slopes of a volcano, capable of killing living creatures.

Isobar

A line on a synoptic weather map connecting all places with equal pressure (e.g., $1\,008\,\text{hPa}$).

Isobar Interval

The pressure difference between two consecutive isobars on a weather map.

Weather Symbols

Standardized symbols used to represent weather conditions and elements at a particular place.

Cold Front

A weather front represented on a synoptic weather chart by a line with solid triangles.

Warm Front

A weather front represented on a synoptic weather chart by a line with solid semicircles.

Occluded Front

A weather front represented on a synoptic weather chart by a line with alternating triangles and semicircles.

Low Pressure System

A weather system labeled with an $\text{L}$ on a synoptic chart, around which air moves clockwise in the southern hemisphere.