SCIENCE 10 QUARTER 1

• earthquake - vibration of the earth due to rapid release of energy, classified as most terrifying process
• faults - enormous overlying crust "squeezed shut"
• focus - also called as "hypocenter", where the slippage begins
• epicenter - directly above the hypocenter
• seismic waves - form of energy that travels through lithosphere and earth's interior
• seismometer - sensitive instrument that can detect an earthquake
• body wave - travel from earth's interior
• p-waves - primary waves, compressional wave
• s-waves - secondary, shear, don't change the volume of the area
• long waves - move the ground from side to side. damaging to the foundations structure
• lithosphere - outer layer
• mantle - thickest layer of the earth
• core - ball, center of the earth
• oceanic crust - younger, beneath the oceans, thinner compared to continental crust, 4 to 7 km, dense basalt, higher density, lower buoyancy, iron, silicon, magnesium
• continental crust - under a continent, less dense, low density, higher buoyancy
• asthenosphere - soft, weak layer, higher temperature than lithosphere
• mesosphere - below the asthenosphere, semi-solid despite of very high temperature, high pressure
• outer core - molten liquid, magnetic field
• inner core - solid, metallic sphere, iron and nickel, solidify
• plate boundaries - edges where two plates meet
• divergent boundary - constructive margin, two plates moves apart
• convergent boundary - destructive margin, move together
• transform boundary - conservative margins, slid past each other
• Alfred Wegener - Jan. 6, 1912, German Meteorologist, theorized that the continents of earth had split and drifted apart over time
• Permian - pangaea, 250 million years ago
• Triassic - Laurasia and Gondwanaland, 200 million years ago
• Jurassic - 145 million years ago
• Cretaceous - 65 million years ago
• puzzle like fit of the continents - the edge of one continent surprisingly matches the edge of another
• evidences from fossils - are preserved remains or traces of organisms from the remote past.
• evidence from rocks and mountain ranges - similar rock formation were found in different continents
• location of ancient climatic zones and coal deposits - coal beds were formed from the compaction and decomposition of swamp plants that lived million years ago. These were discovered in South America, Africa, Indian continent, Southeast Asia and even in Antarctica
• Sea-Floor Spreading - Harry Hess in the 1960's; the process that continually adds new material to the ocean floor while pushing older rocks away from the ridge
• Harry Hess - 1962; proposed mantle convention as the driving mechanism for sea-floor spreading
• Magnetic Reversal - "magnetic flip"; rocks near the ridge are remarkably younger than those farther from the ridge.