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

Earth's Structure and Landforms

The Lithosphere

Earth was formed 4.6 billion years ago. Its internal structure consists of:

• The Core: The center of Earth.
• The Mantle: Surrounds the core.
• The Crust: A thin layer of solid rocks.

The external structure includes:

• The Lithosphere: Composed of the crust and the upper part of the mantle.
• The Hydrosphere: All the water on Earth.
• The Atmosphere: The gaseous layer surrounding Earth.

Continents

Continents are large expanses of dry land surrounded by oceans and seas, covering 29% of Earth's surface. The majority are located in the Northern Hemisphere:

• Asia
• America
• Africa
• Antarctica
• Europe
• Oceania

Islands

Islands are smaller masses of land surrounded by water, often located near the coast of continents. Some islands are grouped... Continue reading "Earth's Structure, Landforms, and Climate Zones" »

Transportation

The eroded materials produce waste that can be classified into three types: ions, small particles, and clasts or fragments of different sizes. Depending on their size, detrital or clastic sediments are classified as gravel or ridges, coarse and fine sand, silt, and clay. The sediments are transported to lower areas by conveyor agents. The most important agent is water, followed by wind and glaciers.

In some cases, such as with particles dissolved in water, all transported materials are alike. However, in most cases, the lighter particles reach farther than the heavier ones, which are usually larger. This is known as selective transport, resulting in a selection of materials by size. Transport occurs in three basic ways: in solution,... Continue reading "Sediment Transport and Deposition Processes" »

Continuation Vertical Dykes

Phases in the construction of dams with floating caissons:

Construction, launching, towing, positioning, anchoring, filling, building superstructure.

Factors to Consider in Building:

1. Previous studies
2. Quarry selection
3. Execution control

Previous Studies:

• Geological studies
• Climate studies
• Bathymetric studies
• Organization and valuation
• Execution

Works for Berthing and Mooring:

That perform the following functions: Contact land-sea, surface crossing of goods, creating a terminal area of transportation systems and storage area of goods.

Types:

Dock: A structure with two vertical planes where vessels are attached to a horizontal plane through which the manipulation of goods is done.

Pontoons and platforms: Areas or pathways through which... Continue reading "Dam Construction & Port Infrastructure: Phases, Factors & Types" »

Evaporator: The Cooling Component

The evaporator is the facility that produces the cooling effect. It's a heat exchanger where heat from the chamber transfers to the refrigerant, causing it to boil. The material must be a good heat conductor for efficient heat transfer. It doesn't necessarily have to be installed inside the enclosure being cooled.

Types of Evaporators

Flooded Evaporator

• The refrigerant is primarily in a liquid state.
• High-performance due to constant temperature difference between fluid and cooling medium.
• Typically uses float level regulators for expansion.

Finned Tube Evaporator

• Smaller size achieved due to increased surface area from fins.
• Fins come in various shapes (circular, square, etc.).
• Attached to the tube mechanically.
• Air circuits

Wood Properties and Characteristics

Physical Properties of Wood

• Anisotropy: Wood exhibits different physical and mechanical properties depending on the direction relative to the grain.
  • Axial: Parallel to the tree's growth.
  • Radial: Perpendicular to the axis.
  • Tangential: Perpendicular to the other two.
• Structure: Conifers typically have a homogeneous structure.
• Density: Mass at 0% moisture is termed anhydrous basis; mass at 12% moisture is termed normal mass.
• Other properties include color, brightness, texture, toxicity, and hygroscopicity.
• When wood has a moisture content higher than its environment, it loses water, leading to shrinkage and potential losses.

Mechanical Properties of Wood

• Compressive Strength: Highest when force is applied parallel to the

Continuation Works: Berthing and Mooring

Design Parameters in Dock Works:

• Direction: Related to winds and currents in the area.
• Draft: Necessary consideration in low-water situations, the vessel's draft, and allowable agitation charge.
• Coronation: The elevation of the dock.
• Efforts: To be considered when calculating the spring's resistance: hydrostatic drive, effort and wave agitation, interstitial pressures in the extrados of the spring, efforts at the berth by the throw of ropes and fenders.

Groundwork for Docking:

• Land and compacts: Good and rocky, incompressible.
• Lots of low compressibility: Loose sand or gravel suitable for the construction of gravity docks.
• Heterogeneous Land: Different layers with alternative materials and sometimes changing

1. The Earth and a Long, Changing History

Sedimentary rocks cover most of the Earth's surface, and are found in strata. These layers often contain fossils. The history of the Earth is divided into two parts:

• Precambrian: The planet's formation, the emergence and development of life, the formation of the primitive atmosphere. It is divided into three eons: Hadean, Archean, and Proterozoic.
• Phanerozoic: At this stage, the Earth remained as we know it, with the current continents and existing life forms (including humans). It is divided into three eras: Paleozoic, Mesozoic, and Cenozoic.

2. Precambrian: The Most Ancient Times

2.1. Hadean: Ancient God of Hades = Hell

The oldest rocks (3800 Ma) are magmatic and metamorphic. There was intense volcanic... Continue reading "Earth's History: From Precambrian to Today" »

Evolutionary Theories

Current thought posits that diverse life forms share a common ancestor known as LUCA. Several theories exist, including Charles Darwin's, which centers on morphological variations in species. These changes, slow, gradual, and driven by natural selection, were later understood to result from DNA alterations. This new understanding shifted the focus from individuals to populations. The gradual evolution concept faces challenges due to the incomplete fossil record.

Homo Sapiens

Our species is distinguished by a highly developed brain, tool-making abilities, language, and extended childhood. Africa, where most hominin fossils have been discovered, is considered the cradle of hominization. The oldest fossils, Ardipithecus ramidus,... Continue reading "Human Evolution and the Origins of Life on Earth" »

Divergent Plate Boundaries

Most divergent boundaries, where plate expansion occurs, are located along mid-ocean ridges. Here, as plates move away from the ridge axis, fractures are created and immediately filled with molten rock rising from the hot asthenosphere below. Through the continuous expansion of the plates and the ascent of magma, new oceanic crust (lithosphere) is added between the diverging plates. This crustal extension is accompanied by alternating episodes of fault formation and volcanism. Adjacent to the expansion axis, crustal blocks are bounded by faults, forming elongated valleys known as rift valleys. As rifting continues, the rift valley lengthens and deepens, eventually expanding into an ocean. At this point, the valley... Continue reading "Plate Tectonics: Divergent, Convergent & Transform Boundaries" »

Methods of Food Preservation

Goal

To prevent the growth of microorganisms, action of environmental agents, chemical and biochemical reactions, and insect attacks. Methods include asepsis, treatment, and conditioning.

Factors Favoring Microorganism Growth

• Temperature
• Oxygen
• Water
• Nutrients
• pH

Traditional Methods

• Salt: Dry (covering with salt) or brine (using a liquid solution with salt and spices).
• Drying: Reducing water content through natural (sun) or artificial (heat, lyophilization) means.
• Smoking: Exposing food to smoke from incomplete wood combustion, providing germicidal, antioxidant, and preservative effects.
• Spices: Adding flavor and acting as preservatives.
• Pickling: Treating food with vinegar or other liquids, often with spices and herbs.
• Adobe: