Notes, summaries, assignments, exams, and exercises for Geology for Other courses

Urban Planning Models

Ensanche - The Hippodamic Model

Early models for expanding cities with old layouts proposed a Hippodamic growth system. In Spain, this model was used in Madrid's widening plan and in Barcelona with Cerdà's plan.

Cerdà's Plan

Cerdà's plan proposed a smaller grid than the original Hippodamic model, with a hierarchy of roads. Over time, this evolved into the Salamanca district, which became obsolete. The urban development was regulated by legislation, including the types of buildings allowed in each block, establishing a social organization among buildings.

The approach was to create courtyards within blocks. Due to their small size, these courtyards were primarily for ventilation and suffered from scale issues over time. The...

Weathering: Mechanisms of Rock Fragmentation and Decomposition

Weathering is the set of processes by which rocks undergo changes, resulting in fragmentation or decomposition. There are two primary types of weathering: physical and chemical.

A. Physical Weathering: Fragmentation of Rock and Soil

Physical weathering is the process of fragmentation suffered by rock and soil materials, primarily by the effect of temperature changes and other physical factors. All soil minerals, including sand, are exposed to the effect of physical factors leading to their division or dispersal. The key physical weathering processes include:

1. Freezing and Thawing: This process occurs in areas where water freezing temporarily exerts an expansion force capable of causing

The Atmosphere is the gaseous layer that surrounds Earth. Its average weight is approximately 5.15 x 10¹⁸ kg (about 5.7 trillion tons).

Properties of the Atmosphere

The atmosphere exhibits various properties, both chemical and physical:

• Chemical Properties:
  • Oxidation
  • Reduction
• Physical Properties:
  • Mobility: Characterized by constant movement.
  • Compressibility: Atmospheric pressure changes with respect to density and temperature. Pressure generally decreases with increasing height and increases with decreasing height.
  • Expandability: Air expands as pressure decreases.
  • Transparency: It is colorless and odorless.
  • Diathermancy: It is transparent to solar radiation.
  • Shape: It conforms to the shape of the Earth.

The atmosphere is composed of gases and vapors, categorized...

Introduction to Geology Fundamentals

The Development of Geological Thought

The understanding of Earth's history evolved through competing theories:

• Mid-1600s – James Ussher: Catastrophism
  • Proposed that Earth’s landscapes were shaped primarily by sudden, short-lived catastrophes.
• 1795 – James Hutton: Uniformitarianism
  • States that the physical, chemical, and biological laws that operate today have operated throughout the geologic past.
  • Famous maxim: “The present is the key to the past.”

Energy Sources of the Earth System

The Earth system is powered by two main sources:

External Processes (Solar Energy)

The Sun drives external processes occurring in the:

• Atmosphere
• Hydrosphere
• At Earth’s surface

Internal Processes (Earth's Interior Heat)

The Earth...

Marxism

Marxism is a philosophy with a close relationship to science. Unlike speculative philosophies following the Platonic tradition, it is politically implemented. It is also a materialist philosophy, a dialectical materialism, which conceives matter not as inert and determined by mechanical laws, but as something dynamic and evolving, with its own internal contradictions as the driving force. Founded by Karl Marx, its study concerns the historical evolution of human societies, emphasizing historical materialism, which focuses on the various modes of production societies use to create their material existence. Historical development is linked to the ideologies and policies of socialism and communism. Its influence on the Frankfurt School...

Spanish Relief: Plateaus and Mountain Systems

The Interior Plateaus and Associated Mountains

The Northern Submeseta

The Northern Submeseta is primarily formed by the Duero River basin. It consists of very high-altitude territories with flat relief, largely unshaped by river erosion. Its geological composition includes Paleozoic rocks (in the West), calcareous sediments, clays, and Tertiary eroded mountain sediments.

The evolution of this region is a result of the Hercynian Orogeny, which formed high mountains. These mountains were subsequently eroded by the Alpine Orogeny. This hard core fractured, creating both sunken and elevated blocks. The plateau itself is inclined towards the Atlantic. An ancient inland lake formed sediments, which were later...

Structural and Roadway Terminology

• Action: Any cause that can produce a solicitation or effect on the structure or its elements.
• Sidewalk: A longitudinal strip, elevated or otherwise, intended for pedestrian traffic.
• Wing Wall: A structural element that contains the embankment sideways, retaining the slopes and protecting the bridge abutment.
• Anden: An elevated sidewalk.
• Support: A load-bearing structure or an element thereof.
• Shoulder (Arcen): A longitudinal paved strip adjacent to the pavement, not intended for vehicle use except in exceptional circumstances.
• Arch: A curved structural element designed to span a void.
• Railing: A sill composed of balusters and rails, generally thin, designed to prevent people from falling.
• Safety Barrier: A vehicle

Stages of Post-Fire Forest Regeneration

• 1. Survival: Underground elements and the seeds of pyrophytes survive, even when the floor is completely damaged.
• 2. Early Regeneration: If the soil was not totally damaged, regeneration starts. During the early years, a pasture consisting of herbaceous plants is formed. If the soil has been removed, this may not start or may take longer.
• 3. 10 to 15 Years: Low shrubs predominate and coexist with the grass. Burned logs decompose and nourish the soil. The animal population increases.
• 4. 30 to 35 Years: Large shrubs predominate, eventually becoming a tree-filled area. This stage allows for mammals such as the fox.
• 5. Forest Formation: The formation of a forest takes 50 to 60 years. Even then, another half-century

Earth's Structure and Tectonic Processes

Continental and Oceanic Crust

• Continental Crust: Thickness varies between 30 and 70km. Forms the continents and is composed mainly of granite.
• Oceanic Crust: Thickness is about 10km. Forms the deep ocean floor and is composed of basalt and gabbro.

Inner and Outer Core

• Inner Core: A solid area with a radius of over 1220km.
• Outer Core: Ranges from 2900km (base of the mantle) to 5150km and is in a liquid state.

Technological Discovery: Mapping the Ocean Floor

Sonar Applications

Using sonar, the ocean floor and deep trenches were mapped, revealing reliefs over 2000m above sea level, thousands of km long, and areas with few sediments.

Magnetic Remanence

Remanence: Magnetic crystals align their orientation with Earth'...

Understanding Soil Exploration: Test Pits & Boreholes

Test Pits and Trial Pits

Test pits, also known as trial pits, are excavations made in the soil to observe and analyze the subsurface layers. These pits are typically dug to a depth of less than 5 meters and have a width of no more than 0.75 to 1 meter. Key requirements for test pit excavation include:

• Wall stability to ensure safety and accurate observation.
• Excavation above the Groundwater Level (GWL) where possible.
• Soil excavation primarily by mechanical means.

Test pits are utilized to explore soil conditions and the sequence of strata up to a depth of 4-5 meters. They also allow for the collection of soil samples for subsequent laboratory testing.

In-Situ Soil Testing Tools

Several tools...