Seismic Risk: Understanding Earthquakes, Causes, and Prevention
Seismic Risk
Earthquakes are destructive geological phenomena, often following floods. Between 1959 and 2003, they caused 800,000 fatalities and heavy material losses.
Basic Concepts: Types of Seismic Waves
Earthquakes are sudden movements or tremors of the Earth’s crust and surface, manifesting internal tectonic activity. Tectonic movements cause internal P and S waves, which extend from a hypocenter. Upon reaching the Earth’s surface, they transform into surface L and R waves, causing devastating
Read MoreEnvironmental Degradation: Causes, Impacts, and Responsible Consumption
1. Environmental Impact Definition
Any alteration or change in the environment caused by human activity or natural phenomena.
2. Natural Phenomena Altering the Environment
Eight natural phenomena that alter the environment:
- Hurricanes
- Earthquakes
- Tornadoes
- Fires
- Volcanic eruptions
- Droughts
- Tsunamis
- Floods
3. Anthropogenic Phenomena Altering the Environment
Seven human activities that alter the environment:
- Deforestation
- Destroying and polluting reefs
- Removing species from their environment
- Invading natural areas
- Building
Soil Formation and Continental Drift
Soils
Soil Formation
Soil is formed by the very slow weathering of rocks.
In spaces between rock pieces, air and water enter, creating an environment for various life forms.
Living organisms and their waste contribute to decomposition through the action of bacteria and fungi.
Substances produced by decomposition combine with minerals, forming new dark minerals called humus.
Soil formed in the same place where weathering occurs is called indigenous soil.
Chips and particles resulting from weathering are
Read MoreSimple Machines and Energy Sources
Simple Machines
Inclined Plane
A ramp serves to raise loads with less effort. This sloping ramp requires a smaller force than lifting the load directly, although the distance traveled will be greater.
Lathe
A cylinder with a handle coupled to a power multiplier.
Wedge
A double inclined plane where the force applied perpendicular to the base is multiplied and transmitted to the wedge faces.
Connecting Rod
A bar linkage attached to a handle, transforming circular motion into alternating linear motion or vice-
Read MoreBiomes, Mutations, and Human-Environmental Interactions
Biomes of the World
b) The Taiga Coniferous Forest
Characteristics: Low annual average temperatures, but above 0°C. Precipitation usually falls as snow.
Location: Between 45° and 60° North latitude, covering large areas of Canada, the United States, Russia, Siberia, and Scandinavia. Also found in subalpine mountain regions.
Flora: Pine and fir forests. The evergreen canopy creates dense shade year-round, hindering the growth of herbs and shrubs.
Fauna: Squirrels, beavers, bobcats, wolves, deer, woodpeckers,
Read MoreEarth’s Interior Structure and Composition
Study of Earth’s Interior
Much of our knowledge about the Earth’s structure and composition comes from indirect studies, as direct observation is limited to approximately 10km deep within the crust.
Direct Methods
These methods involve analyzing material obtained through boreholes.
Indirect Methods
These methods rely on analyzing and interpreting the Earth’s physical characteristics, including seismic wave behavior, gravity, density, magnetism, internal heat emission, and meteorites.
Direct Methods
Based
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