Stratigraphic Principles and Earth’s Climate History
Stratigraphic Principles for Sedimentary Rocks
Principles of Stratigraphy
- Superposition: In undisturbed settings, the oldest sedimentary rocks are deposited first at the bottom of the sequence.
- Originally Horizontal and Lateral Continuity: Sedimentary beds are originally deposited horizontally and extend laterally in all directions.
- Cross-Cutting: Faults, igneous rocks, or unconformities that cut across sedimentary beds are younger than the beds they cut.
- Unconformity: An erosion surface representing
Air Sampling Instruments and Methods for Occupational Health
Pneumoconiosis
“Dust accumulation in the lungs and tissue reactions in the presence of this dust.”
There are two different types of pneumoconiosis:
- Collagen: Reactions with production of fibrous tissue and permanent alterations or destruction of alveolar structure caused by a fibrogenic dust (silica, asbestos) or a reaction to a non-fibrogenic dust (coal mineral production massive fibrosis).
- No Tissues: Those in which reaction occurs with reticulin and the honeycomb structure remains intact. This reaction
Weather and Climate: A Comprehensive Guide
Weather and Climate
Weather
Weather refers to the state of the atmosphere at a particular place and time. It encompasses various aspects such as temperature, humidity, precipitation, wind, and cloud cover. The science that studies weather is called meteorology.
Climate
Climate, on the other hand, represents the long-term average weather patterns observed in a specific region. To determine the climate of a country, an observation period of at least 30 years is required. The study of climate is known
Read MoreEcosystems and Environmental Factors: Impacts and Adaptations
Ecosystems and Environmental Factors
An ecosystem is a system formed by a group of organisms of different species (or biocenosis), the environment in which they live and its physical/chemical characteristics (or biotope), and the interactions that are established between them. Biocenoses are determined by many factors resulting from:
- The characteristics of the biotope.
- The actual presence or variations
1.1 Environmental Factors and Their Impacts
Environmental factors are all the components of the ecosystem
Read MoreAsphalt Emulsion Tests: A Comprehensive Guide
Asphalt Emulsion Tests
Electrical Charge Test
This test determines the electrical polarity of asphalt emulsion globules to identify if they are anionic (negative charge) or cationic (positive charge). An electrical current is induced through the emulsion using two electrodes, and the attraction of asphalt globules to the electrodes is observed.
pH Test
This test determines the potential hydrogen (pH) of the emulsion to identify the type: anionic emulsions are alkaline, while cationic emulsions are acidic.
Read MoreHuman Impact on the Environment: Understanding the Environmental Crisis
The Human Impact on the Environment
1. Natural Resources
Natural resources are materials derived from nature that humans use to satisfy their basic needs and desires. These resources are categorized as:
- Non-renewable resources: Exist in fixed amounts on Earth and are generated over long geological periods.
- Renewable resources: Replenish naturally at a rate faster than their consumption.
- Potentially renewable resources: Can be replenished naturally but are susceptible to depletion if overused.