SLIPPERY WHEN WET

The cause of the magnitude 7.2 Kobe, Japan, earthquake in January 1995 is unknown. Zhao(…) developed a tomographic model of tire velocity structure of the crust beneath the epicenter and extended aftershock zone. Earthquakes provoke several different kinds of shock waves. The images show that the hypocenter of the earthquake was in a distinctive zone, characterized by low P-wave and S-wave velocities and a high Poisson's ratio, suggestive of the presence of fluids that may have helped facilitate the earthquake.

SCIENCE - December 13,1996.

A questão refere-se ao texto cujo vocabulário se segue:

• slippery = escorregadio

• wet = molhado

• earthquake = terremoto

• unknown = desconhecido

• crust = crosta

• beneath = embaixo de

• several = diversos, vários

• waves = ondas

• ratio = proporção

• low = baixo

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