GEOL 106 Lecture Notes - Lecture 10: Seismic Wave, Seismometer, Radius

• School: Queen's University
• Department: Geological Sciences and Geological Engineering
• Course: GEOL 106
• Professor: Daniel Layton- Matthews

Document Summary

P stands for primary, s stands for ssecondary: to measure distance to an earthquake focus, we use travel times ime between the. P and s wave arrivals at your seismometer: s and p wave distance goes further from the focus of the earthquake. Hence, at the focus, the s and p wave occur almost simultaneously. For eartquakes: since we didn"t know seismic velociies at depth, we needed to irst create an empiracle travel-ime graph. For quakes of known locaion and ime, obtain the p-s arrival-ime diferences from seismometers around the world. S and p waves on the graph are not straight, they are curved because of the seismic waves. Empiracle travel-ime graph (on textbook: determines how far away the earthquake is. Why are there travel-ime curves instead of straight lines: the velociies don"t remain constant at depth. Deeper in the earth, the waves spend part of their ime at higher velociies.