Notes, summaries, assignments, exams, and problems for Geology

Causes of Soil Pollution

• Industrial Activities

  • Chemical Spills and Discharges: Factories and manufacturing plants often handle chemicals that, if spilled or improperly disposed of, can seep into the soil.
  • Mining Operations: Mining activities expose and disperse heavy metals and other pollutants, which can contaminate surrounding soils.
  • Industrial Waste: By-products of industrial processes, such as slag and sludge, are often disposed of in landfills or directly onto land, leading to soil contamination.

• Agricultural Practices

  • Pesticides and Herbicides: These chemicals are used to control pests and weeds but often contain harmful substances that can persist in the soil and disrupt ecosystems.
  • Fertilizers: Excessive use of nitrogen and phosphorus-based

Tunnel Lining Fundamentals

Purpose of Tunnel Lining

• Support tunnel structure.
• Prevent water ingress.
• Improve durability.

Types of Tunnel Lining

• Concrete
• Shotcrete
• Steel
• Masonry

Sections of Tunnel Lining

• Crown: Top of the tunnel.
• Inverts: Bottom of the tunnel.
• Walls: Sides of the tunnel.

Types of Foundation Footings

• Spread Footing (Pad footing) – Supports a single column.
• Strip Footing (Continuous footing) – Continuous foundation beneath a wall.
• Raft Foundation – Covers the entire building footprint; distributes load on weak soils.

Understanding Foundation Settlement

• Definition: Downward movement due to soil compression.
• Notes:
  • Coarse soils: Settlement often ≤ 25 mm (rarely > 50 mm).
  • Loose sands below water table: More settlement.
  • Clay: Consolidation settlement,

Aircraft Flight Dynamics

The relationship between the four primary forces acting on an aircraft:

• Lift > Weight: Plane rises
• Weight > Lift: Plane falls
• Drag > Thrust: Plane slows
• Thrust > Drag: Plane accelerates

Definitions of Flight Forces

What is Thrust?

Answer: Thrust is a force that moves the airplane forwards through the air.

What is Drag?

Answer: Drag is a force that opposes thrust. It is a type of friction and makes objects harder to move.

What is Lift?

Answer: Lift is a force that allows an aircraft to climb or stay in the air.

What is Weight?

Answer: Weight is the effect of gravity on an object.

Airport Ground Operations Vocabulary

Key terms and their Spanish translations:

• De-ice
• Sweeper - camión limpiador
• Tow truck - grúa
• Push back - empujador
• Baggage

Material Failure Mechanisms and Concepts

Creep Phenomenon

Creep is the slow and permanent deformation of a material when it is subjected to a constant load or stress for a long period of time at high temperature. Creep becomes significant when the temperature is above 0.4 times the melting temperature of the material (in Kelvin).

Stages of Creep:

Creep occurs in three stages, shown by a creep curve:

1. Primary Creep (Transient Stage)
   • Creep rate decreases with time.
   • Material becomes strain-hardened.
2. Secondary Creep (Steady-State Stage)
   • Creep rate becomes constant.
   • This is the longest and most important stage.
3. Tertiary Creep
   • Rapid increase in creep rate.
   • Formation of cracks and necking.
   • Ends with fracture.

Factors Affecting Creep:

• Temperature
• Applied stress
• Time

Cenozoic Era Periods

The periods of the Cenozoic Era, in order from oldest to youngest, are Paleogene, Neogene, Quaternary.

Plate Tectonics and Orogenies

Convergent and Transform Margins

• What is an example of a continental-continental convergent plate margin? Himalayas
• What is an example of a transform plate margin? San Andreas Fault

North American and Alpine Orogenies

• The orogenic event of the North American Cordillera, which began in the Late Cretaceous and extended into the Cenozoic, is the Laramide Orogeny.
• The Alpine orogeny resulted in the formation of which mountains? Alps, Atlas, and Pyrenees.
• The rapid northward movement of India resulted in the formation of the Himalayan mountains.
• How did orogens in the Pacific region differ from the Himalayan

1. What are the innermost layers of Earth?

The inner core is the innermost physical layer of the Earth. The core is the innermost chemical layer.

2. What evidence indicates that the outer core is liquid?

Evidence from earthquake waves indicates that the outer core is liquid.

3. How does Earth generate a magnetic field?

It surrounds Earth.

4. Compare the lithosphere and the asthenosphere

The lithosphere is a rigid layer. The asthenosphere is a plastic layer.

5. How is the crust different from the mantle?

The mantle has more iron. The crust is less dense than the mantle.

6. What are the four layers of the mantle?

• Lithosphere
• Asthenosphere
• Uppermost mantle
• Lower mantle

7. Which layer of the mantle has the greatest pressure? Explain

The lower mantle because pressure... Continue reading "Earth's Layers and Systems: Composition and Properties" »

1. Global Concepts & Protocols

Problems and Global Issues

• Resource Depletion: Finite resources, renewable resources, and resource degradation.
• Environmental Pollution: Air, water, and soil pollution, including causes and mitigation methods.
• Global Climate Change (全球气候变化)
  • Key Substances (GHGs): Primarily $\text{CO}_2$ (Carbon Dioxide), $\text{CH}_4$ (Methane), $\text{N}_2\text{O}$, and CFCs.
  • Mechanism (Greenhouse Effect): Solar shortwave radiation enters Earth $\rightarrow$ Ground heats up and emits longwave infrared radiation $\rightarrow$ GHGs absorb this heat in the atmosphere $\rightarrow$ Global warming.
  • Consequences: Sea level rise, extreme weather, loss of biodiversity.
  • Corresponding Conventions: Kyoto Protocol & Paris Agreement.