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1994 Bolivian Earthquake. Eric Kiser. 1994 Bolivian Earthquake. Moment Magnitude (Mw): 8.3 Epicenter: 13.84°S and 67.55 °W Depth: 631km. Outline. Rupture Characteristics Comparison with other Deep Earthquakes Tectonics. Silver et al., 1995. Directivity Analysis. Silver et al., 1995.
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1994 Bolivian Earthquake Eric Kiser
1994 Bolivian Earthquake • Moment Magnitude (Mw): 8.3 • Epicenter: 13.84°S and 67.55 °W • Depth: 631km
Outline • Rupture Characteristics • Comparison with other Deep Earthquakes • Tectonics
Directivity Analysis Silver et al., 1995
30km by 50km Rupture Plane • 40s Duration • 1.25 km/s Velocity • Rupture plane is too large Silver et al., 1995
Other Rupture Properties • No Isotropic Component (Okal, 1996) • Friction melting (Kanamori et al, 1998) • Efficiency: 0.036 • Non-Radiated Energy: 1.4x1018 J • 52,000°C Temperature Increase • Slow Rupture Velocity and Large Slip
Differences in the 1994 Bolivia and Tonga Earthquakes Wiens and McGuire, 1995
Bolivia Earthquake Tinker et al., 1995
Tectonic Setting Kirby et al., 1995
Tectonic Setting Kirby et al., 1995
Tectonic Setting Kirby et al., 1995
Kinks from compression • Kinks meet resistance at the • lower mantle • Slab Thickening Kirby et al., 1995
Summary • Deepest earthquake ever recorded • Rupture extent, no isotropic component, and seismic efficiency have important implications for deep earthquake mechanisms • The majority of deep earthquakes may not exhibit these rupture characteristics