DCN- We have been observing since March a large number of earthquakes with a intensity superior to 4.0 on the region known as the Ring of Fire, is such activity normal?
USGS- We find it normal, specially after a major earthquake like the one that hit Japan March 11th. Even the aftershocks intensity is not out of the usual after an event like this.
DCN- Can Japan expect a major earthquake on Tokai region due to some pressure in the Phillipine plate from the pacific plat after the 9.0 that recently hit Japan?
USGS- Plates shifting like they did , we expect that the stress regime in the plates also changes, however we don't have the science needed to be sure and know that the Tokai earthquake will happen due to the 9.0 earthquake.
DCN- Can somehow this affect the west coas of US? Has the number of earthquakes increase on this region after 11th March?
USGS- Its unlikely that an earthquake in west coast of the US results as direct influence of the Japan earthquake. There is no evidence that there is a correlation between earthquakes and so far apart.
for more also see here