Endo-Exogenic

Continental Drift Theory

- Theory that continents were once part of a single landmass that broke apart and have moved to their present locations.

- Can drift apart from one another and have done so in the past

Divergent Boundaries:
Tension

Rock gets THIN in the middle as it is PULLED apart. This stress is called ____

Normal Fault

- It happens when the rock snaps from the stress of tension
- Rock drops down as it breaks

Mid-ocean ridges
Rift Valleys
Fissure Volcanoes

Features of Divergent Boundaries

Type 1: Oceanic-Continental

Ocean plate colliding with a less dense continental plate

Type 1: Oceanic-Continental
Type 2: Oceanic-Oceanic
Type 3: Continental-Continental

There are 3 types of Convergent Boundaries:

Type 2: Oceanic-Oceanic

Ocean plate colliding with another ocean plate

Trench
Ex: Aleutian Islands, Alaska

The more dense plate slides under the more less plate creating a subduction zone

Type 3: Continental-Continental
Ex: Himalayas or the Rockies

- A continental plate colliding with another continental plate
Have Collision Zones:
_ A place where folded and thrust faulted mountains form

Alfred Wegener

- A German scientist who proposed the theory of continental drift in the 1900s (PANGAEA)

Pangaea

- The single landmass that was present 200 million years ago

1. Continents "fit together like a puzzle piece"
2. Fossil Evidence
3. Mountain ranges match
4. Climatic evidence (glaciers) close to the equator

Wegener's Evidences

Satellites (Laser Geodynamics Satellite) LAGEOS

- They are used to measure the movements of continents

Plates

- Large pieces of earths crust and upper mantle (Lithosphere) that move on top due to convection currents
- Broken into sections

Theory of Plate Tectonics

The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.

True

Plates move slowly in different directions and cause different geologic events

Convection Currents

They are in the mantle that move the plates as the core heats the slowly-flowing asthenosphere

Asthenosphere

The elastic/plastic-like part of the mantle

Plate Boundaries

The edges of Earth's tectonic plates

Fault

A break in the Earth's crust where rocks have slipped past each other

Divergent, Convergent, and Transform Boundaries

3 Types of Plate Boundaries

Divergent Boundaries

A plate boundary where two plates move AWAY from each other

Key words: Rifting causes Seafloor Spreading, Rift Valleys on Continents

Convergent Boundaries

- A plate boundary where two plates move toward each other
- Places where plates crash(crunch) together or subduct (one sinks under)

Keywords: Connecting, rock goes up (crunches) to make folded mountains
Rock goes down "under" subduction zones

Convergent Boundaries:
Compression

- Boundaries between two plates that are colliding. This stress is called ___________

Subduction Zone

- The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary
- Volcanoes occur

Reverse Fault

- What happens when the rock is squeezed from the Stress of Compression?
- Rock is forced UPWARD as it is squeezed

Transform Boundaries

- A plate boundary where two plates move past each other in opposite direction
- May cause Earthquakes when the rock snaps from the pressure

Keywords: They shake the ground, Scissors/Sheers

Shearing (or "cut")

- How is the rock broken at Transform Boundaries?
- Rock is PUSHED in two OPPOSITE DIRECTIONS (or sideways but no rock is lost) -- This stress is called

San Andreas Fault in California

Famous fault at a Transform Boundary

A strike-slip fault

What happens when the rock is sheared from the stress of shearing?
- Rocks on each side of the fault SLIP PAST EACH OTHER as they break

Gradation Processes

Weather, Mass Wasting, Erosion, Transportation and Deposition

Geomorphic Processes

Physical processes which create and modify landforms on the surface of the Earth

Endogenous Processes

- Large-scale landforms building and transforming processes
- They create relief

a. Volcanism
b. Plutonism

Igneous Processes

Volcanism

Volcanic eruptions --> Volcanoes

Plutonism

Igneous intrusions

a. Folding
b. Faulting
c. Lateral Faulting

Tectonic Processes (also called Diatrophism)

Folding

Anticlines, Synclines, Mountains

Faulting

Rift Valleys, Graben, Escarpments

Lateral Faulting

Strike-Slip faults

Earthquakes

Evidence of present-day tectonic activity

Exogenous Processes

- Also called Gradational Processes, they comprise degradation and aggradation - they modify relief

Weathering --> Mass Wasting --> Erosion --> Transportation --> Deposition

Gradational Processes:
- A continuum of Processes

1. Gravity, Flowing Water(from rivers),
2. Moving Ice (Glaciers),
3. Waves and Tides (Oceans and Lakes),
4. Wind,
5. Plants,
6. Organisms,
7. Animals,
8. and Humans

Geomorphic Agents

Degradation Processes
a. Weathering
b. Mass Wasting
c. Erosion and Transportation

- Also called Denudation Processes

a. Deposition

Aggradation Processes

Weathering

- Is disintegration and decomposition of rocks.
- If No transportation involved --> produces REGOLITH
- involves mechanical or physical disintegration and/or chemical decomposition
- processes begin in microscopic spaces

1.) Physical or Mechanical Weathering
2.) Chemical Weathering
3.) Biological Weathering

Types of Weathering

Physical or Mechanical Weathering

- via weather elements (high temp, extreme cold)
- disintegration and decay of rocks and freeze-thaw cycles
- no change in chemical compositions of rocks

Exfoliation

Due to thermal expansion/contraction and/or release of pressure when buried rocks are uplifted and exposed

Frost Wedging

Cycles of freezing and thawing causes frost weathering

Salt Wedging

- Salts in rocks expand due to thermal action, hydration and crystallization
- Salts like (Ca, Na, Mg, K and Ba) have a tendency to expand

Chemical Weathering

- Decomposes rocks through a chemical change in its minerals

Oxidation

Important in iron-rich rocks -reddish coloration like RUST

Hydrolysis

Igneous rocks have much silica which readily combines with water

Carbonation and Solution

Carbon dioxide dissolves in rainwater to form weak carbonic acid, this reacts with calcium carbonate, leading to the formation of soluble calcium bicarbonate

Biological Weathering

- Plants and animals contribute to weathering

Roots

Physically break or wedge rock

Lichens

- Algae and Fungi living as single unit
- Remove minerals and weaken rocks by releasing acids
- Burrowing animals can increase weathering

Erosion and Transportation

Various Geomorphic Agents, associated Processes,
and resulting Erosional Features

Erosional:
Fluvial Morphology

Erosional:
Flowing Water

Perennial streams and entrenched channel, rapids, waterfalls, plunge, pools, potholes, meandering, streams, bank erosion, oxbow lakes, etc.

Humid Regions

Erosional:
- Eolian Landscapes
- Deflation hollows, ventifacts, yardang, etc.

Erosional:
Wind

Erosional:
- Coastal Morphology
- Sea cliffs, sea caves, sea arches, sea stacks, wave-cut beaches, etc.

Erosional:
Tides and Waves

Erosional:
- Glacial Morphology
- Glacial Troughs (U-shaped valleys), Hanging Valleys, Glacial Lakes

Erosional:
Moving Ice

Deposition

Various geomorphic agents, associated processes and resulting Depositional Features

Deposition:
Fluvial

Deposition:
Humid Regions and Arid Regions

Alluvial fans, Baja, Das Piedmont Alluvial Plains, Playas, Playa Lakes, Salinas (Salt Flats)

Arid Regions

Deposition:
Eolian

Deposition:
Sand dunes (Barchans, Parabolic, Transverse, Star) and Sand Sheets

Deposition:
Coastal

Deposition:
Sea beaches and coral reefs

Deposition:
Glacial

Deposition:
Alpine and Continental

Deposition:
Alpine

Deposition:
Glacial Drifts, Tills, Moraines (Lateral, Medial, End, Terminal, Recessional, and Ground)

Deposition:
Continental

Deposition:
Till plains, outwash plains, drumlins, eskers, kames, erratic