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

Water Resources: A Vital and Limited Resource

Water is a dominant factor for the development of life. It is a limited resource, since the available quantity is conditioned by its unequal distribution in space and time. Nearly two billion people live in countries facing water stress. The problems presented with respect to water as a resource are the increase in consumption and scarcity. Agricultural practices, industrial and urban activities, as well as the increase of population and improvement in the quality of life in society, increase water requirements.

Solutions for Sustainable Water Use

• Improving efficiency in water use
• Sharing available water in solidarity
• Introducing new technologies in industries
• Implementing water policies based on efficiency,

Earth's Origin and Early History

The Nebular Theory: Origin of Earth and Solar System

The most accepted theory regarding the origin of the Earth is the Nebular Theory. This theory posits that the solar system emerged from a nebulous cloud of gas and dust, likely resulting from the explosion of a previous star.

Evolution of the Primitive Atmosphere

The primitive atmosphere originated from gases released by volcanoes, primarily methane, carbon dioxide ($ ext{CO}_2$), and hydrogen. Initially, the archaic seas were rich in organic substances utilized by early prokaryotes. As these substances became scarce, photosynthetic autotrophs, specifically cyanobacteria, emerged. Their activity led to the impoverishment of $ ext{CO}_2$ and the significant enrichment... Continue reading "Earth's Origin, Geological Time, and Fossil Formation Principles" »

Characteristics of Castilian Language: Geographical Variants

Except for the flow of its lexicon, the state of the Castilian language today is very similar to that presented in the eighteenth and nineteenth centuries, when it became definitively fixed and modernized. However, some linguistic features can be identified in our own day:

• Phonetic Generalization of Sibilance: The pronunciation of 'z' (a, o, u) and 'c' (e, i) as /s/ is generalized across America, similar to what happened in the Canary Islands and much of Andalusia.
• Yeísmo: This phenomenon has spread throughout America and much of Spain. It involves the confusion of the sounds of 'll' and 'y', which has caused the loss of the distinct 'll' sound and makes it impossible to orally distinguish

Environmental Definitions

Here are some fundamental environmental definitions:

Aquifer

An aquifer is an underground water reservoir. Aquifers form when precipitation water filters through the ground, finds a waterproof layer, and accumulates on it. Their waters can be discharged through rivers and springs or directly into the sea.

Acid Rain

Acid rain is precipitation with a higher degree of acidity than normal. It occurs when emissions of sulfur and nitrogen mix with water vapor in the air and become diluted solutions of sulfuric acid and nitric acid, which then fall to the Earth's surface as rain. It causes changes in vegetation, soil, water, and buildings.

The Ozone Layer

The ozone layer lies between 15 and 55 km in height and filters ultraviolet... Continue reading "Key Environmental and Economic Concepts Explained" »

Plate Tectonics and Earth's Structure

Plate Boundaries

Mid-ocean ridges are constructive plate boundaries where lithospheric plates separate, leading to ocean growth.

Oceanic trenches are destructive plate boundaries where the oceanic lithospheric plate subducts beneath another plate.

Earth's Crust

Continental crust extends 30 to 70 km deep beneath continents.

Oceanic crust extends 5 to 10 km deep beneath oceans.

Three major ocean ridges exist in the Pacific, Atlantic, and Antarctic Oceans.

Volcanoes

Magma

Magma, molten rock found deep within the Earth's crust, can withstand temperatures of 1000 to 1200 °C.

Magma composition consists of silicate rock, gases, and water vapor.

Magma viscosity is determined by the amount of silica (SiO2); higher silica content... Continue reading "Exploring Earth's Dynamic Processes: Crust, Volcanoes, and Earthquakes" »

Sustainable Development

According to the Brundtland report, where this term first appeared, sustainable development is "development that meets the needs of the present without compromising the ability of future generations to meet their own needs." This requires a respectful attitude towards all people, all living beings, and all ecosystems.

This involves:

1. Consuming resources below their regeneration capacity.
2. Disposing of waste in quantities that nature can absorb.
3. Utilizing renewable energy sources.
4. Ensuring development reaches the entire population.

Sustainable development has three components: economic growth, environmental conservation, and social equity. It's important not to confuse the concepts of growth and development. Economic growth refers... Continue reading "Sustainable Development, Atmosphere, and Pollution" »

Parthenon: An Architectural Marvel

I observe the front, main elevation, facade, or side elevations of a structure. The primary material used in this construction is marble. A significant portion of the outer space is visible, along with a part of the building's interior. The structure rests upon a base (crepidoma) with steps (crepis) extending along its entire perimeter.

Structural Elements

The load-bearing elements include walls and columns. Where visible, the wall presents meticulously matched stones, indicating a regular ashlar construction. The columns do not directly rest on the stylobate. The shaft features sharp edges or ridges, separated by grooves. The capital comprises an abacus, echinus, and collarino.

Supporting elements include the... Continue reading "Parthenon & Maison Carrée: Ancient Greek Temples" »

Materials in a Building

Structure

The strong skeleton of the building, consisting of:

• Cimientos (Foundations)
• Pillars
• Vigas (Beams)
• Forjado (Slab/Flooring)

They can be made of concrete, reinforced concrete, or steel.

Siding

Serves as external protection against atmospheric agents. Consists of: facade walls and the roof structure (steel support on which the roof is constituted).

Partitions

Internal walls or divisions that sort and distribute the interior space. Typically made of bricks and plaster.

Coatings

Applied to floors, walls, and ceilings to provide a finished surface. Consist of materials such as paint or fabrics.

Types of Rocks

Magmatic or Igneous Rocks

Formed by the solidification of molten material from inside the Earth, e.g., Granite.

Sedimentary

Flow: l/min, m³/h. Pressure: 1 bar = 10⁵ = 1 atm = Pascal = 1 kp/cm². Absolute pressure: Real pressure, including atmospheric pressure. Relative or differential pressure: This takes into account the atmospheric pressure. Temperature: K = 273 ° + °C. Performance: Utilization relationship between the magnitude and extent consumed, expressed in %. Boyle's Law - Mariotte: The volume occupied by a mass of gas at constant temperature is inversely proportional to the supporting pressure. Charles's Law: The volumes occupied by a mass of gas at constant pressure are directly proportional to temperature variations. Gay-Lussac's Law: At constant volume, the pressure of a gas is directly proportional to temperature variations. Combined or General Law:

The El Niño and La Niña Phenomena

The normal situation along Peru's coast involves trade winds pushing surface water westward across the Pacific, leading to the upwelling of nutrient-rich water and fertilization of the area. These winds originate from an anticyclone located over Easter Island and dissipate near the Asian continent.

Understanding El Niño

The El Niño phenomenon is characterized by the excessive heating of the surface waters in the eastern Pacific. It typically occurs every 3-5 years and lasts approximately 18 months. This event happens when trade winds subside, allowing the surface water to heat up and form a storm system.

Understanding La Niña

La Niña is considered an exaggeration of the normal situation, occurring when trade... Continue reading "Understanding El Niño, La Niña, and Frontal Precipitation" »