Tectonics and Landforms

What are the two types of convergent plate boundaries?

1. Collision (continent–continent); 2. Subduction (oceanic–continental or oceanic–oceanic)

Where do you find each type of convergent boundary?

Collision: Where two continental plates meet (e.g., Himalayas); Subduction: Where an oceanic plate sinks beneath another plate (e.g., Andes).

What landforms are associated with tectonic collision?

Folded mountain ranges and high plateaus.

What landforms are associated with tectonic subduction?

Volcanic mountain chains, ocean trenches, and frequent earthquakes.

What is a transform plate boundary?

A boundary where plates slide past each other horizontally.

What is a famous North American example of a transform boundary?

San Andreas Fault, California.

What are divergent plate boundaries?

Boundaries where plates move apart, allowing magma to rise from the mantle.

Why are volcanoes common at divergent boundaries?

Rising magma fills the space created by plate separation and erupts as lava.

What are mantle hot spots?

Fixed plumes of hot magma from the mantle that "burn" through moving plates above them.

Name two U.S. hot‑spot locations.

Hawaii and Yellowstone.

What is a fault?

A fracture in Earth’s crust where significant movement has occurred.

What are the four main types of faults?

1. Normal; 2. Reverse; 3. Thrust; 4. Strike‑slip

What is a normal fault?

A fault where the hanging wall moves downward relative to the footwall due to tensional (pulling) force.

What is a reverse fault?

A fault where the hanging wall moves upward due to compressional (squeezing) force.

What is a thrust fault?

A specific type of low‑angle reverse fault, very common in major mountain-building events.

What is a strike‑slip fault?

A fault where the motion is primarily horizontal (side‑to‑side).

What type of fault is the San Andreas Fault?

Strike‑slip fault.

What is a syncline?

A fold in rock layers that bends downward, forming a U-shape.

What is an anticline?

A fold in rock layers that bends upward, forming an arch or $\cap$-shape.

What is a dome?

A circular or elliptical uplifted structure where rock layers dip outward in all directions from the center.

What is a basin?

A circular or elliptical structural depression where layers dip inward toward the center.

Why can synclines become highs and anticlines lows after erosion?

Erosion removes weaker rock first; the underlying structure doesn’t always equal surface resistance, so the harder layers eventually determine the highest points of topography.

What are cuestas?

Asymmetrical ridges formed by tilted sedimentary layers; they feature a gentle slope on one side (dip slope) and a steep scarp on the other.