Plate Tectonics: Earth S Major Tectonic Plates Make up 14 Plates

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