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

Sunspot

The most visible manifestation of solar activity.

Solar Activity

All the sunspots, bursting events, and associated phenomena.

Solar Cycle

The nearly periodic 11-year change in solar activity (i.e., changes in the number of sunspots, flares, and other associated manifestations).

Wolf Number

A measure of the amount of sunspots, used to quantify solar activity.

Solar Wind

Solar material flowing into interplanetary space; the Sun's atmosphere expanding radially outwards in all directions.

Climate Change

A change in the statistical distribution of weather patterns.

Weather

The state of the atmosphere at any given place and time.

Climate

The average (mean) of weather parameters over a long period of time.

Meteoroid

A small rocky or metallic body traveling... Continue reading "Essential Astronomical and Meteorological Definitions" »

The Wilson Cycle: Earth's Dynamic Plate Movement

The Wilson Cycle describes the cyclical opening and closing of ocean basins and the fragmentation and reassembly of continents through plate tectonic processes. It typically involves several stages:

1. Continental Fragmentation and Rift Formation

   Plate dynamics generate tension that can cause a large continental mass to fracture along an axis. As the separation of plates continues, the lithosphere sinks, forming an intercontinental rift valley.

2. Formation of an Expanding Ocean

   If the rift is near a sea, the valley will flood, and a narrow sea will be formed. As the plates continue to separate, a mid-ocean ridge develops along the center, and new oceanic lithosphere expands.

3. Ocean Reduction and Continental

Structure of the Earth

Earth consists of four concentric layers: inner core, outer core, mantle, and crust. The crust is made up of tectonic plates, which are in constant motion. Earthquakes and volcanoes are most likely to occur at plate boundaries.

Inner Core

The inner core is in the center and is the hottest part of the Earth. It is solid and made up of iron and nickel with temperatures reaching 5,500ºC.

Outer Core

The outer core is the layer surrounding the inner core. It is a liquid layer, also made up of iron and nickel. Temperatures are similar to the inner core.

Mantle

The mantle is the widest section of the Earth, with a thickness of approximately 2,900km. It is made up of semi-molten rock called magma.

Crust

The crust is the outer layer of... Continue reading "Structure of the Earth and Plate Tectonics: A Comprehensive Guide" »

What is the Environment?

We can define the environment as the space in which some kind of natural exchange that makes life possible takes place. The environment is not only the space itself but also the different forms of life that inhabit it. That is, if we were speaking of space only, we would be referring merely to a spatial location. On the other hand, the concept of environment expands this idea to include everything related to life developing in that space. Today, the environment is a topic very much in vogue because of the debate generated around its care and how human activity contributes increasingly more rapidly to damage it.

The environment is nothing other than the medium, precisely the place or space in which different life-related... Continue reading "Defining the Environment and Understanding Human Impact" »

• Pollution is the addition of a substance or an agent to an environment by human activity, at a rate greater than that at which it can be rendered harmless by the environment and which has an appreciable effect on the organism within it.

• Basically… contamination of nature which affects living organisms.

• Substances exposed to the atmosphere and littering by humans.

POINT SOURCE POLLUTION (Coming from a direct source)

• The pollutants are coming from clear identifiable sources: sewage into a river.

• Easier to see who is polluting.

• Easier to manage and monitor.
  

NON-POINT SOURCE POLLUTION (NPS)

• Release of pollutants from numerous sources: car fumes, etc.

• Almost impossible to detect the origins of the pollutants.

• Rain can collect various forms of nitrates and

Collapse

Collapse is the reduction in wood size during drying before fiber saturation. It manifests as a corrugated surface due to crushed wood tissues and sometimes internal lens-shaped cracks. Collapse occurs in some wood species when dried slowly at high temperatures or humidity, or during rapid outdoor drying. It's more intense on radial cut faces than tangential ones. This defect causes significant wood loss during surfacing and reduces mechanical strength. Tangential shrinkage is greater than radial shrinkage, often separating wood tissues parallel to the weaker radial parenchyma cells. The pith is also susceptible to damage, developing cracks and crevices. In eucalyptus, avoid sawing the pith to achieve good quality dried products.

Drying... Continue reading "Wood Defects and Degradation" »

Understanding the Deep Ocean: Vessels and Instruments

Oceanographic Vessels

Conshelf

Conshelf: A diver who lives and operates both inside and outside a submarine refuge for an extended period.

Alvin

Alvin: A manned deep-ocean research submersible owned by the United States Navy and operated by the Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Massachusetts.

Aluminaut

Aluminaut: The world's first aluminum submarine. This experimental vessel, an 80-ton, 15.5-meter (51 ft) manned deep-ocean research submersible, was built by Reynolds Metals Company to promote the utility of aluminum.

Essential Oceanographic Instruments

Water Bottle

Water Bottle: A container used to hold water, liquids, or other beverages for consumption.

Reversing Thermometer

Reversing

Disaster Preparedness and Environmental Challenges

Preparing for Volcanic Eruptions

We already know what a volcano and a volcanic eruption are, as well as the Volcanic Explosive Index (VEI) and the damage they can cause. But what should we do? How do we protect ourselves?

It is clear that a volcanic eruption is a phenomenon we cannot avoid, and it is difficult to predict when it will happen. Therefore, we must be prepared for what might occur, especially if we live near major volcanoes, such as Mount St. Helens or the Tambora volcano.

Apart from taking preventative measures, it is our duty to be informed.

Essential Emergency Kits

The first thing we need, whatever the disaster, is an emergency kit. We may have to survive without external help after... Continue reading "Global Risks: Volcano Safety, Environmental Action, and Nuclear Waste Management" »

Core Energy and Power Concepts

Transform (verb): To change or alter the appearance or form of something.

Source: Origin.

Resource: A supply or source of material that can be used.

Heat: A form of energy generated by being hot.

Supply: The total amount of a specific good or service that is available to consumers.

Release (verb): To emit, give off, or discharge.

Absorb (verb): To take in or consume.

Electrical Grid and Distribution

Power station: Power stations generate electric current in very large quantities to supply the national grid.

National grid: A system of special wires that take electricity from power stations (places where electricity is made) to all parts of a country.

Substation: Substations are an important part of the national grid. They... Continue reading "Essential Energy and Electricity Infrastructure Terms" »

Coastal Sediment Transport Processes

The sea transports the load or sediment it obtains through erosion in the same ways that a river does. There are four primary methods of transportation:

• Suspension: Fine sediment is carried within the water, making it look muddy or murky.
• Solution: Dissolved material is carried along in solution, making it invisible to the naked eye.
• Traction: Larger pebbles and cobbles are rolled along the sea bed by the force of the water.
• Saltation: Small pebbles are moved when one pebble hits another, causing it to bounce in a chain reaction.

Understanding Longshore Drift

As well as being moved up and down a beach, sediment can also be moved along it if the incoming waves are driven by onshore winds at an oblique angle to the... Continue reading "Coastal Sediment Transport and Marine Deposition" »