PLATE TECTONICS
Plate tectonics: Earth’s major tectonic plates make up 14 plates.
Drifting Continents: Reasons:
1) Similarities of types of rock
2) Distribution of fossil species
3) Other lines of evidence
225 Million Years ago, all continents were in one: Pangea moving 6 cm per year: steady slow movement of tectonic plates over the intervening time by break up of Pangea, and brought continents to their present position. In the future, San Francisco and LA will be next to each other.
Magma: hot stuff in asthenosphere
Lava: magma on surface of lithosphere
HAZMATS
Hazmats: Hazardous Material:
Toxicology: The study of harmful effects of chemicals on human and environmental health.
Toxicity: acute: sudden
Chronic: over a period of years
Carcinogenic: cancer- causing
Threshold level: the level below which no ill effects are observed
Dose: The amount of chemical taken at once.
Response: The effect
The nature of chemical hazards: Hazmats:
1) Ignitability: Substances that catch fire readily (e.g. gasoline and alcohol)
2) Carrosivity: Substance that corrodes storage tanks and equipment (e.g. acids)
3) Reactivity: Substance that are chemically unstable and may explode or create toxic fumes
when mixed with water (e.g. explosives, elemental phosphorus and concentrated sulfuric acids)
4) Toxicity: Substances that are injurious to health when they are ingested or inhaled (e.g. Chlorine gas, ammonia, pesticides and formaldehyde).
5) Radioactivity material: Cause radioactivity emissions: alpha particle or helium nucleus, beta particle or electrons, gamma rays or electromagnetic radiation (e.g. uranium, radium, plutonium)
Authorities:
Environmental Protection Agency (EPA): A federal agency with environmental protection regulatory and enforcement authority.
Occupational Safety and Health Administration (OSHA): Part of US department of Labor. The regulatory and enforcement agency for safety and health in most US industrial sectors.
Air Quality Management District (AQMD): Smog Control agency
American Conference of Governmental Industrial Hygienists (ACGIH): An organization of professionals engaged in occupational safety and health programs.
The Material Safety Data Sheet (MSDS)
Geological time scale
Formation of Earth 4600 million years ago
Archean: Oldest microfossils 2500 mya
Water-based life
First eukaryotes (having nucleus)
Protezoic: 580 mya
Cambrean: First vertebrates 530 mya
Ordovician Silurian: Land Plants 438 mya
Fish, Mass extinction
Devorean: Amphibians, mass extinction 367 mya
Carboniferous: Reptiles 350 mya
Permean: 248 mya
Triassic: turtle 220 mya
Jurassic: Flowering plants, mammals, birds, and dinosaurs 180 mya
Cretaceous: Mass extinction of life 75 mya
Tertiary: Early primates, primitive whales, bats 50 mya
Homohabilus: 2 mya