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

Conditions for Life

Several key factors make life on Earth possible:

• Water
• A magnetic field
• A protective atmosphere
• Carbon compounds
• An energy source

Biotic and Abiotic Factors

Biotope: The non-living part of an environment, including all abiotic factors.

Biocenosis: All living things from every species within a defined area that provides the necessities for survival.

Ecosystem: A natural environment where living things interact with each other and their surroundings.

Trophic Levels

Ecosystems often have distinct trophic levels:

• Tertiary consumers
• Secondary consumers
• Primary consumers
• Producers

Predation

Predation is an interspecific relationship where one living thing kills another for food.

Soil Composition

Topsoil: Composed of partially decomposed organic matter... Continue reading "Understanding Our Ecosystem" »

Continental Environments

Fluvial (River) Environments

• Stream/river channels
• Sand bars
• Levees
• Floodplains

Lacustrine (Lake) Environments

• Vary in depth, salinity, biological activity, and sediment
• Source sand and mud

Aeolian (Desert) Environments

• Little to no annual precipitation
• Low vegetation
• High wind
• Transport of sand grains
• Dunes contain well-sorted, well-rounded, and frosted (scratched during wind transport) sand grains sand and dust

Paludal (Swamp) Environments

• Area of anoxic (deoxygenated) water where plant material accumulates but cannot decompose (coal)
• Very low energy environment

Glacial Environments

• Glacial meltwater and sediment transport
• Sand, mud, gravel

Transitional Environments

Deltas

• Fan-shaped deposits of sediment
• Coarser sediment is commonly deposited

Energy Resources

Nonrenewable Energy

Nonrenewable energy is a source of energy that exists in limited quantities and, once used, cannot be replaced except over millions of years.

Examples:

• Coal (fossil fuel)
• Oil (fossil fuel)
• Natural gas (fossil fuel)
• Uranium (rock)

Renewable Energy

Renewable energy is a source of energy that can be replaced in a relatively short period of time.

Examples:

• Hydroelectric
• Solar
• Geothermal
• Wind
• Biomass
• Nuclear fusion (potentially in the future)

Most renewable energy originates from the sun.

Fossil Fuels

Oil, natural gas, and coal are known as fossil fuels because they were formed underground from the remains of once-living organisms. Fossil fuels are relatively inexpensive and are usually readily available, but their use creates... Continue reading "Renewable & Non-Renewable Energy Resources: A Comprehensive Guide" »

The Hydrosphere

Definition

All the water that exists on our planet is collectively known as the hydrosphere. This includes water found on the ground, surrounding us, and underground.

Forms of Water

• Solid: Ice, glaciers, snow, and ice caps.
• Liquid: Rivers, seas, oceans, and rain.
• Gas: Steam and water vapor.

Distribution of Water

• Planet: 71% water
• Marine Water: 97%
• Fresh Water: 3%

Water Uses

Water is essential for various purposes, including agriculture, industries, homes, public services, energy production, transportation, and recreation.

Waters of Mexico

Mexico's water resources include marine and fresh water, with diverse classifications, uses, and locations.

Marine Water

Mexico has a vast coastline with access to the Pacific Ocean, the Gulf of California,... Continue reading "Understanding the Hydrosphere, Atmosphere, and Climate" »

Coastal Dynamics: Waves and Marine Erosion

Waves are fundamental forces shaping our coastlines. Their interaction with the shore involves two primary movements: swash and backwash.

Understanding Wave Dynamics

Swash and Backwash: The Basics

• Swash: When water rushes up the beach.
• Backwash: When water drains back down the beach.

Destructive Waves: Shaping Coastlines

Destructive waves are powerful forces that remove material from the beach. They are characterized by a weak swash and a strong backwash, pulling sand and pebbles back down the beach as the water retreats.

• Often steep, high waves that are close together.
• Crash down onto the beach.
• Come in very quickly, at a rate of 10 to 15 waves per minute.
• Also known as plunging waves.

Constructive Waves: Building

Climograma

Un Climograma é un gráfico no que representamos simultaneamente os valores da temperatura media mensual, mediante unha liña, e os de precipitación media mensual, mediante barras verticais, dos doce meses do ano. No eixe vertical esquerdo situaremos as frecuencias de temperatura en oC (Graos Centígrados), tendo en conta se hai temperaturas inferiores a 0oC, pois nese caso haberá que deixar un espazo para representalas. As temperaturas medias mensuais están unidas por unha liña vermella 1.No eixe vertical dereito representaremos as precipitacións (en mm), tendo en conta as proporcións que debemos utilizar en función do total, sabendo que será necesario indicar o dobre do valor empregado no eixe vertical esquerdo. A diferenza... Continue reading "Climograma and Pollution: Environmental Impact in Spain" »

Abnormally Pressured Shallow Formations

Abnormally pressured shallow formations can result from upward fluid migration due to:

• Leaky fault
• Leaky cement or casing
• Improperly abandoned underground blowout

Steps Not Included in Well Drilling

Steps in well drilling do not include: building drilling equipment.

Drilling Rig Power System Selection

To select the power system of a drilling rig, one needs to consider the weight of the drill string.

Formation Fracture vs. Pore Pressure

Is formation fracture pressure always higher than formation pore pressure? Yes.

Causes Excluded from Abnormal Pore Pressure

Causes of abnormal pore pressure do not include: drilling.

When Not to Use Oil-Based Drilling Fluids

We would not use oil-based drilling fluids to increase safety,... Continue reading "Essential Principles of Petroleum Well Drilling" »

Celestial Mechanics & Timekeeping

Time Definitions and Earth's Motion

• Solar Day: The time from one local noon to the next; Earth rotates slightly more than 360° relative to the Sun.
• Sidereal Day: The time for a distant star to appear in the same position in the sky; approximately 4 minutes shorter than a solar day.
• Earth's Precession: A slow wobble in Earth's rotational axis, completing a cycle approximately every 26,000 years.

Moon Phases, Tides, and Orbit

• First Quarter Moon: Rises around noon, sets around midnight.
• Third Quarter Moon: Rises around midnight, sets around noon.
• Spring Tides: Occur during full and new moons, resulting in the highest tidal range.
• Neap Tides: Occur during first and third quarter moons, resulting in the lowest tidal

Mineral Resources: Key Concepts and Applications

13. Factors for Commercially Viable Mineral Extraction

Three factors that make mineral extraction commercially viable are:

• The mineral content of the ore must be in sufficient quantities.
• The type of formation or structure determines the relative ease with which mineral ores are extracted.
• The cost of mineral extraction.

14. Measures for Mineral Conservation

Three important measures for the conservation of minerals include:

• Adopting improved technologies to use low-grade ores at lower costs.
• Recycling metals using scrap metals.
• Using substitutes such as aluminum instead of copper, etc.

15. Uneven Distribution of Mineral Resources in India

The statement “Mineral resources in India are unevenly distributed”... Continue reading "Mineral Resources: Extraction, Conservation, and Key Applications" »