How does volcnoes and eatrhquakes affect humans and the environment

Earthquakes: Earthquakes cause destruction of homes and the land, Some "hits" from Earthquakes may be strong and some may be less. But the affect it has on the environment is: Surface faulting, Tectonic uplift and subsidence, tsunamis, soil liquefaction, ground resonance, landslides and ground failure.

Human:During shaking Hazards and Human made structures.. probably the most important direct shaking effects are not only hazard associated with Earthquakes other effects such as landslides, liquefaction, and tsunamis have also played important part in destruction.   

Volcano:
Human: If the ash fall is very heavy it can make it impossible to breathe.Lava flows are are almost always too slow to run over people. but they can certainly run over houses, roads and any other structures. Pryoclastic flows are mixtures of hot gas and ash, and they travel very quickly down the slopes of volcanoes.

Environment: When volcanoes erupt, they emit a mixture of gases and particles into the air. Some of them such as ash and sulfur dioxide, have a cooling effect, because they (Or the substances they cause) reflect sunlight away from the earth. Others such as CO2, cause warming by adding the greenhouse effect.

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