250 likes | 378 Views
Fri day , March 23 nd. 1 Attendance 2 Go over Review Sheet Test Pass Back papers. Da’ Lab. When did the P-wave hit? When did the S-Wave hit? Subtract to get the difference. Use the chart to find the epicenter distance Mark the edge of the paper with the time difference
E N D
Friday, March 23nd • 1 Attendance • 2 Go over Review Sheet • Test • Pass Back papers
Da’ Lab • When did the P-wave hit? • When did the S-Wave hit? • Subtract to get the difference. • Use the chart to find the epicenter distance • Mark the edge of the paper with the time difference • Move paper to find the place where the two lines are that far apart. • Look down to see the epicenter distance • Use the safety compass to draw the circle - with the correct distance around the city.
Earthquakes The sudden shaking of the ground.
I. Earthquakes • Are sudden trembling or movement of the ground • There are over 1 Million Per year (1 per second) • A major cause of earthquakes is faulting
I. Earthquakes • Faulting –sudden movement of rock along planes of weakness in the earth’s crust • Faults - planes of weakness in the Earth’s crust. • Rock is stressed to the breaking point and the two halves have an elastic rebound. • Great masses of rock suddenly scrape past one another.
Epicenter Focus
I. Earthquakes • Focus - the point where the rock breaks. • Epicenter - the point on the Earth’s surface directly above the focus. • Analysis of seismic waves allows the determination of the location of epicenters.
II. Earthquake Waves • When faulting occurs, vibrations called seismic waves spread out in all directions from the focus. • Seismograph - a device that detects measures, and records the motions of the earth associated with seismic waves.
II. Earthquake Waves • Seismogram- the line that was recorded on paper by a seismograph • Magnitude - the total energy released by an earthquake
P-Waves • Primary / Compressional • First to arrive • Fastest • Can travel through Feverything: • solids, liquids and air
S-Waves • Secondary Waves • Shear Waves • Second to arrive • Travels only through • solids
Name Earthquake Vocabulary • Earthquake – • Faulting – • Fault- • Focus – • Epicenter – • Seismic- • Seismograph - • Seismogram - • Magnitude - • Richter Scale - • Mercalli Scale - • P-wave (primary) - • S-wave (secondary) -