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

Disaster Preparedness and Environmental Challenges

Preparing for Volcanic Eruptions

We already know what a volcano and a volcanic eruption are, as well as the Volcanic Explosive Index (VEI) and the damage they can cause. But what should we do? How do we protect ourselves?

It is clear that a volcanic eruption is a phenomenon we cannot avoid, and it is difficult to predict when it will happen. Therefore, we must be prepared for what might occur, especially if we live near major volcanoes, such as Mount St. Helens or the Tambora volcano.

Apart from taking preventative measures, it is our duty to be informed.

Essential Emergency Kits

The first thing we need, whatever the disaster, is an emergency kit. We may have to survive without external help after... Continue reading "Global Risks: Volcano Safety, Environmental Action, and Nuclear Waste Management" »

Core Energy and Power Concepts

Transform (verb): To change or alter the appearance or form of something.

Source: Origin.

Resource: A supply or source of material that can be used.

Heat: A form of energy generated by being hot.

Supply: The total amount of a specific good or service that is available to consumers.

Release (verb): To emit, give off, or discharge.

Absorb (verb): To take in or consume.

Electrical Grid and Distribution

Power station: Power stations generate electric current in very large quantities to supply the national grid.

National grid: A system of special wires that take electricity from power stations (places where electricity is made) to all parts of a country.

Substation: Substations are an important part of the national grid. They... Continue reading "Essential Energy and Electricity Infrastructure Terms" »

Coastal Sediment Transport Processes

The sea transports the load or sediment it obtains through erosion in the same ways that a river does. There are four primary methods of transportation:

• Suspension: Fine sediment is carried within the water, making it look muddy or murky.
• Solution: Dissolved material is carried along in solution, making it invisible to the naked eye.
• Traction: Larger pebbles and cobbles are rolled along the sea bed by the force of the water.
• Saltation: Small pebbles are moved when one pebble hits another, causing it to bounce in a chain reaction.

Understanding Longshore Drift

As well as being moved up and down a beach, sediment can also be moved along it if the incoming waves are driven by onshore winds at an oblique angle to the... Continue reading "Coastal Sediment Transport and Marine Deposition" »

Natural Disasters

• Avalanche

• Drought

  Drought is the unusual dryness of the soil caused by levels of precipitation.

• Earthquake

  An earthquake is the result of a sudden release of energy.

• Famine

• Flood

  A flood is an overflow of water that covers the earth.

• Hurricane

• Landslide

• Tornado

  A tornado is a column of violent rotating air.

• Tsunami

  A tsunami consists of huge waves caused by an underwater earthquake or a volcanic eruption.

• Volcano

  Volcanoes can cause widespread destruction and consequent disaster in various ways.

• Wildfire

Weather

• Blizzard

• Cloudy

• Damp

• Dry

• Foggy

• Hailstones

• Heatwave

• Icy

• Rainy

• Snowy

• Stormy

• Sunny

• Thunder and Lightning

• Warm

• Wet

• Windy

Preindustrial Societies

Hunter-Gatherer Societies

Hunting, fishing, and gathering fruits and roots were essential for survival in hunter-gatherer societies. These societies had very little impact on the environment.

Agricultural Societies

Agricultural societies formed larger groups. The agricultural revolution transformed the way resources were obtained through:

• Plant species cultivation
• Hydraulic work (reservoirs, dykes, terraces, canals, and channels)

The impact on the environment was relatively small.

Industrial Societies

Industrial Revolution

From the 18th to the 20th century, a new economic model emerged based on the mass production of goods using enormous amounts of energy. This led to serious environmental problems, including the over-exploitation... Continue reading "Environmental Issues and Sustainable Solutions" »

Convergent Boundaries and Plate Tectonics

Convergent boundaries are where the edges of two plates are moving towards each other. The lithosphere is destroyed.

Three Types of Convergent Boundaries

1. Converging Continental and Oceanic Plates

At boundaries where a continental plate and an oceanic plate collide, a phenomenon called subduction takes place; in other words, the denser oceanic plate slides under the continental plate. The subducting plate sinks into the mantle and forms a trench. This sinking can be detected as the lithosphere rubs against the rocks in the mantle, causing earthquakes at many points of the Benioff zone, which is the surface of the sinking plate. The force of the plates raises the continental crust, creating a boundary... Continue reading "Convergent Plate Boundaries and Cellular Genetics" »

Localitation:

• Amazon
• Congo
• Indonesia

Temperature:

• High around 25º all months
• Hot weather

Spaciouness:

• Low temperature
• Less than 3º

Precipitation:

• High and regular more than 2000 mm

Vegetation:

• Rainforest
• Central Africa
• India
• Central America
• Surrounds the Equatorial climate

Temperature:

• High more than 20º all months
• Hot weather

Spaciouness:

• A few between (3º-10º)

Precipitation:

• Irregular, two seasons: summer and Winter
• High 1000 mm
• More than 2000 mm

Vegetation:

• Tropical Gallery Forest
• Sahara
• Kalahari

Temperature:

• High temperature
• Average temperature higher than 20º

Spaciouness:

• Big spaciouness termal
• Differents
• Day/night
• Summer/winter

Precipitation:

• Low (< than 200 mm)
• Irregulars

Vegetation:

• Just Oasis

Localitation:

• Occidental Europe
• South Coast of Chile
• West of Canada
• New Zealand

Temperature:

Physical Geography and Climate Science Quiz

1. Tropical rainforests would most likely be found in:
   a. Brazil
   b. North Africa
   c. Cuba
   d. Italy
2. Climates exhibiting continentality:
   a. Have severe winters
   b. Often have very warm summers
   c. Exhibit great temperature ranges
   d. Exhibit all of the above
3. In comparison with the west coast of the United States, the east coast has a climate that is:
   a. Milder in summer but more severe in winter
   b. More severe in summer but milder in winter
   c. More severe in both summer and winter
   d. Milder in both summer and winter
4. Many of the major and most extensive wheat-producing regions on Earth are located where ____ climates prevail.
   a. Savanna
   b. Temperate Grasslands
   c. Tropical Rainforest
   d. Desert
5. Mosses, lichens, permafrost, and no

Types of Stress

• Compression: pressure from both sides
• Tension: pressure from pulling apart
• Shear: opposite pressure, land grinding past other land

Strength of the Crust

The strength of the continental crust (quartz and feldspar) increases with depth then weakens.

• Brittle (surface/less depth, temp, and pressure): stress makes rock fracture, but rock remains intact
• Ductile (more depth, temp, and pressure): stress makes rock flow in solid state, rock resists deformation.

Joint

The crack where the rock was pulled apart

Stresses that form joint:

• Burial and tectonic forces: force from every side of the rock, straight cracks
• Cooling and contraction: ex-when mud dries it cracks
• Unloading: pressure in an uplift, mountain

Fault

Rocks have slipped passed one another

Movement