Hi Todd. It is a subduction fault. The Tokai earthquake is expected to occur at the place where the "Philippine Sea plates" subducts beneath the "Eurasian plate". Other name called by the Japanese is "Trench earthquake", as it is expected to occur in the area of the Suruga Trough (The deepest part in Suruga Bay).

No. Tokyo doesn’t have a 5+ once or twice a month. They don’t even have that many once a year. Take Care…Don in creepy town

The big one, which already has a name ("The Tokai Earthquake"), is most likely to crumble buildings in 74 cities across Shizuoka Prefecture, according to research conducted on fault lines in the Chubu area. Residents in at least 56 cities in Yamanashi Prefecture would be jarred by the Tokai Earthquake, which experts think will have a magnitude of 8.0 on the Richter scale. Nineteen cities in Kanagawa and 16 in Nagano are also expected to incur heavy damage.

However, the trembler would threaten only Shinshiro City in Aichi - 60 kilometers east of Nagoya - and the lone city of Nakatsugawa in Gifu.

Naturally, other areas of Japan would also suffer damage if the big one hits, but according to a research group made up of officials from Aichi, Gifu, Kanagawa, Nagano, Shizuoka and Yamanashi prefectures, governments throughout these regions have already prepared contingency plans and have laws in place to handle the aftermath of the Tokai Earthquake.

Still, the question looming is, "When is it expected to hit?"
In 1854, a massive undersea earthquake took place when tectonic plates between Japan and the Philippines jolted the Tokai region.

But the largest quake here in recent memory was a 1997 tremor in eastern Aichi that registered a magnitude of 5.8 (or 4 on the Japanese intensity scale). Prior to that, the only shaker to equal that mark was a 4 that hit the area in 1983.

Dr. Katsuhiko Ishibashi, formerly an associate professor at Tokyo University, predicted in 1978 that a powerful earthquake would soon rock the Tokai region.
According to Aichi Prefecture, not many of its 30 faults are seismically active, and just 10 tremors that have occurred in recent years have measured above 3 on the Japanese intensity scale.

Even the Great Hanshin Earthquake, which recorded a 7.2 on the Richter scale when it decimated Kobe in 1995, was measured at 3 on the Japanese scale here in Nagoya.
In other words, the city has been stirred, not shaken.
Just in case a major quake hits the area, though, a number of local municipalities already have strategies in place.

According to the Aichi officials, this is the only earthquake for which specific laws have been drawn up in anticipation of its arrival.

But according to one earthquake researcher, no news is bad news.
"It has been more than 20 years since (Ishibashi) first predicted the Tokai Earthquake and just because it hasn't occurred yet doesn't mean everything is OK," Dr. Yoshimitsu Okada, of the National Research Institute for Earth Science and Disaster Prevention in Ibaraki Prefecture, said in a telephone interview.

Okada said that the institute has set up 100 locations in the Tokai and Kanto regions to collect data on the geographic features of the area in hopes of predicting when the quake will hit.

Based on those studies, Okada said that movement of the earth is causing friction and stress that is gradually building up enough strength to trigger a major shaker.

And he said that "some say the later it comes, the bigger it will be."
According to Okada, the data the institute has collected suggests that the movement over the past 20 years has slowed down. He says that after the Tokai Earthquake hits, experts will point to this data as a warning sign that disaster was on its way.