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

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" »

Climatic Conditions in Argentina

The diverse climatic conditions in Argentina were largely shaped after the last glaciation. Due to the country's significant latitudinal extent, the amount of solar energy received varies, decreasing as one moves southward. Temperature variations are influenced by factors such as altitude, the location of mountain ranges, and proximity to the sea.

Temperature Variations and Influences

In the highlands, temperatures are low due to the effect of altitude, despite some areas being at the latitude of the Tropic of Capricorn. For instance, the Puna region is situated at an altitude of 3,500 meters above sea level. The north-central region of the country experiences the strongest continental effect, characterized by... Continue reading "Argentina's Diverse Climate: Regions and Weather Phenomena" »

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:

National Water Plan

Project coordinating river basin management plans and water resources. The 2008 plan, aligned with EU guidelines, focuses on environmental actions (supply, treatment, purification, irrigation, forestry impact, channels) and works regularization, including the Ebro water transfer and construction of new dams.

Water Transfer

Interbasin transfer from water surplus to deficit areas. Currently, 38 are operational, including the Tajo-Segura. The National Hydrological Plan proposes new transfers, like the Ebro to the Mediterranean. However, protests in regions like Aragon and potential environmental impacts (Ebro Delta) have led to exploring alternatives, such as the Rhone-Catalonia transfer.

Reservoirs

Artificially stored water extensions... Continue reading "Spanish Environmental Management: Plans, Laws, and Initiatives" »

Types of Rocks

Sedimentary: Rock formed by material eroded and transported by geologic agents, including sedimentary basins, which have been compacted over time.

Magmatic (Igneous): Originated by the cooling of a molten rock mass. There are two types:

• Plutonic: Cooling magma within the Earth's crust. They have a crystal texture.
• Volcanic: Rapid cooling of lava on Earth's surface. They have a microcrystalline texture.

Metamorphic: Rocks formed in the interior of the crust due to the high pressures and temperatures that produce changes in the minerals.

Definitions

Volcanism: The surface expression of rocks melting within the crust.

Earthquake: Brief and sudden movements of the Earth's crust.

Continental Drift: Slow, horizontal movement of continents.

Isostasy:

Raw Materials and Their Properties

Raw materials are substances extracted directly from nature. They can be classified as:

• Animal: Leather, wool, silk
• Vegetable: Flax, esparto, wood
• Mineral: Iron ore (hematite), clay

A material ready for processing is called a field-ready material. These materials undergo physical and chemical transformations to create products like paper, board, and wood.

Technological Products

A technological product is any object created by humans to meet their needs and improve their quality of life. These objects are made from various materials (e.g., books, tables). The process of creating technological products involves transforming raw materials into usable materials and then into the final product.

Common Technological Materials

The... Continue reading "Understanding Raw Materials, Properties, and Technological Products" »