CHAPTER 11 SECTION 2 FEATURES OF EARTHQUAKES SEISMIC WAVES EARTHQUAKE WAVES THAT TRAVEL THROUGH EARTH ENERGY IS RELEASED WHEN ROCKS PASS THEIR ELASTIC LIMIT. ENERGY IS RELEASED AT THE FOCUS KINDS OF WAVES PRIMARY WAVE-MOVE BACK AND FORTH IN THE DIRECTION WAVE TRAVELS. FASTEST WAVE SECONDARY WAVE-SECOND FASTEST, PARTICLES MOVE AT RIGHT ANGLES IN THE DIRECTION WAVE TRAVELS SURFACE WAVES-SLOWEST BUT MOST DESTRUCTIVE WAVE, MOVES PARTICALS IN ALL DIRECTIONS. OCCUR WHEN WAVE REACHES SURFACE. CAUSE MOST DAMAGE AT THE EPICENTER LOCATING AN EPICENTER NEED AT LEAST THREE SEISMOGRAPH STATIONS TO FIND AN EPICENTER MEASURING SEISMIC WAVES SEISMOGRAPH RECORDS THE ENERGY RELEASED ON A DRUM OF PAPER SEISMOGRAPH STATIONS FROM AN EARTHQUAKE, PRIMARY WAVES ARRIVE FIRST, SECONDARY WAVES SECOND AND SURFACE WAVES LAST BASIC STRUCTURE OF EARTH SOLID CORE, LIQUID OUTER CORE, FLUIDY LOWER MANTLE, THICKER, GOOEY UPPER MANTLE, AND CRUST ON THE SURFACE MANTLE IS LARGEST LAYER CRUST CAN BE 60 KM THICK IN SOME MTN. AREA AND ONLY 5 KM THICK ON THE OCEAN BOTTOM MAPPING EARTH’S INTERNAL STRUCTURE THEY STUDY THE WAY THE WAVES TRAVEL THROUGH THE PLANET. THIS TELLS THEM IF IT IS A LIQUID OR A SOLID