1. Volcanic Hazards Primary Effects -lava flows -pyroclastic eruptions -poisonous gas emissions Secondary Effects -mudflows and debris avalanches -flooding (glacial outburst floods) -tsunamis -seismicity -atmospheric effects and climate change Volcanic Hazards along the Cascadia Subduction Zone Predicting Eruptions Monitoring the Movement of Magma -seismic studies -magnetic field changes -electrical resistivity Physical Anomalies and Precursor Phenomena -ground deformation -change in heat output -change in the composition of gases -local seismic activity

2. Volcanic Hazards Primary Effects -lava flows -pyroclastic eruptions -poisonous gas emissions Secondary Effects -mudflows and debris avalanches -flooding (glacial outburst floods) -tsunamis -seismicity -atmospheric effects and climate change Volcanic Hazards along the Cascadia Subduction Zone Predicting Eruptions Monitoring the Movement of Magma -seismic studies -magnetic field changes -electrical resistivity Physical Anomalies and Precursor Phenomena -ground deformation -change in heat output -change in the composition of gases -local seismic activity

4. Pahoehoe Flow, Hawaii Aa Flow, Hawaii

5. Basaltic lava flow, Hawaii.

8. Lava flow induced fire, Hawaii.

11. Landslide north face of Mt. St. Helens May 18, 1980.

12. Mt. St. Helens May 18, 1980

13. Mount St. Helens: Pyroclastic flow May 18, 1980.

19. Pompeii, Italy 79AD

30. Tephra distribution from Mt. Mazama, Longvalley and Yellowstone eruptions.

31. Tephra distribution of Cascade volcanoes

33. Isopachs of Glacier Peak tephra distribution (13,100 yr BP).

34. Volcanic Hazards Primary Effects -lava flows -pyroclastic eruptions -poisonous gas emissions Secondary Effects -mudflows and debris avalanches -flooding (glacial outburst floods) -tsunamis -seismicity -atmospheric effects and climate change Volcanic Hazards along the Cascadia Subduction Zone Predicting Eruptions Monitoring the Movement of Magma -seismic studies -magnetic field changes -electrical resistivity Physical Anomalies and Precursor Phenomena -ground deformation -change in heat output -change in the composition of gases -local seismic activity

36. Causal Factors for Lahar Flows

39. Lahar flows from Mt. Pinatubo, Phillipines.

42. Mt. Rainier’s glacial ice is a major potential source

44. Oceola Lahar (~5200 yr BP) near Enumclaw, WA.

49. Unconsolidated pyroclastic deposits on north face of Mt. St. Helens source of lahar flows.

50. Reworked pyroclastics incorporated into Mt. St. Helens lahar deposits.

52. Volcanic Hazards Primary Effects -lava flows -pyroclastic eruptions -poisonous gas emissions Secondary Effects -mudflows and debris avalanches -flooding (glacial outburst floods) -tsunamis -seismicity -atmospheric effects and climate change Volcanic Hazards along the Cascadia Subduction Zone Predicting Eruptions Monitoring the Movement of Magma -seismic studies -magnetic field changes -electrical resistivity Physical Anomalies and Precursor Phenomena -ground deformation -change in heat output -change in the composition of gases -local seismic activity