Earth Science: Rocks, Minerals, and Earth Systems
Earth Materials
Rocks and Minerals
Rocks are aggregates of minerals formed by geological processes. A mineral is a naturally occurring element or inorganic compound with a definite chemical composition and atomic structure.
Rock Classification
- Igneous: Formed from the consolidation of magma.
- Sedimentary: Formed from the consolidation of sediments.
- Metamorphic: Formed from other rocks within the Earth’s crust that have undergone transformation.
The Rock Cycle
The rock cycle is the continuous process of transformation
Read MoreEarth’s Surface Processes: Weathering, Erosion, Sedimentation, and Soil
External Geodynamic Processes
External geodynamic processes occur on the Earth’s surface, driven by gravitational forces and solar energy. Important geological agents include rain and wind. These processes lead to weathering, erosion, transportation, and sedimentation.
Weathering
Weathering is the set of changes experienced by materials of the lithosphere in contact with the atmosphere, hydrosphere, or biosphere.
Physical Weathering
- Fissuring: Rupture or disintegration of rocks due to tectonic stress.
Understanding Material Classification and Properties
Classification of Materials: The most general classification of materials is as follows:
a. Metal: Ferrous, Nonferrous
b. Nonmetallic: Organic, Inorganic
Ferrous Metals: Ferrous metals, as their name suggests, have iron as their main component. Their main features include high tensile strength and hardness. The principal alloys are obtained with tin, silver, platinum, manganese, vanadium, and titanium.
The main products of representatives of metallic materials include gray iron castings, malleable iron,
Read MoreWater Contamination: Sources, Effects, and Mitigation
Water Pollution: An Overview
Water pollution is the introduction of harmful materials, energy, or conditions that degrade water quality. It stems from the release of substances or energy forms that alter the natural composition of water, with the degree of contamination depending on its intended use. Water pollution is primarily caused by human activities.
Types of Contamination
Diffuse: This type of contamination has a wide area of impact and no specific point source (e.g., natural runoff).
Point Source:
Read MoreOceanic Lithosphere and Plate Tectonics
TEMA – 8. Plate Tectonics
Oceanic Lithosphere
Study Skills.
For seabed analysis, the following methods are used:
- Surveys to identify rocks.
- Sonar to map the undersea terrain.
- Geophysical research cruises collecting seismic and magnetic data.
- Submersibles designed for direct observation and sampling.
Undersea Structures
Continental Shelf. Submerged prolongation of the continent. Maximum depth 200 meters.
Continental Slope. Steep (40%) slope to the edge of the continental shelf.
Abyssal Plain. Area of low slope.
Universe Formation, Structure, and Evolution
Origin of the Universe
Universe: Set of all matter and energy existing in space. The observable part is the observable universe.
Cosmology: Science that studies the universe.
Age
13.7 billion years. Events: Discovery of America; Birth of Jesus Christ; Beginning Egyptian empire; Appearance of Homo sapiens.
Dimensions
The universe is measured using a unit called a light-year, which corresponds to the distance light travels in one year.
Composition
- 73% dark energy (counteracts gravity)
- 23% dark matter (does