Q. News is that scientists have learned how to switch earthquakes “off” and “on.” So why not switch off the fault that might bring the Big One to San Francisco?

A. The largest recorded quake was in Chile in 1960, where a slab of rock 800x200 kms slipped 21 meters past the adjacent rock, magnitude 9.5, says Nigel Calder in “Magic Universe.”

Since there are 100,000 times more quakes of magnitude 2 than 7, predicting the big ones is bound to be uncertain, as when forecasters failed to warn of the deadly Kobe earthquake in Japan in 1995.

Scientists can now switch earthquakes on by using water under pressure pumped in through boreholes close to fault lines, raising the possibility of “stage-managing” a lot of small quakes to relieve the San Andreas fault strain buildup, thus saving San Francisco.

Some 500 boreholes 4,000 meters deep might be needed to do this. An intriguing idea, yes, but politically explosive, says Calder. “Since every earthquake in California would be blamed on this, whether it was really responsible or not, litigation against the government would continue for centuries.”

And who knows? The little ones just might backfire and trigger the dreaded Big One. Kanamori’s caution: “Better not pull the tiger’s tail.”

Q. Geologically, how is oil formed, and why is there so precious little of it to be found?

A. Things die, and some sink deep to the bottom of an ocean or swamp – unless they get gobbled on the way by other still living things, says University of Alberta Earth scientist John Waldron. So only a small fraction of these remains find their way to a deep reservoir “source” without oxygen, where decomposition can’t occur.

Here over millions of years they get compressed by accumulating sediment, heated under pressure and “cooked” to liquid oil. Now, industry must find the stuff and get it to the surface before it is lost (as so much is) to “seeps.”

Regarding oil’s scarcity, one recent estimate put world reserves at about 1,300 billion barrels (1,300,000,000,000). Yet nearly 30 billion barrels are pumped each year, says geologist Brian Willis of Texas A&M University, enough to fill over 400 cylindrical tanks, each a football field in diameter and a mile high!

“So while there’s still plenty of oil for the getting, world demand is so great we may well run short of affordable oil before alternative energy sources are developed.”

Q. What hip new way are baseball hitters able to “practice” their batting wherever they choose, even while at home or being driven to the ballpark?

A. By having footage of all their at-bats on their video iPods, permitting review of their tendencies against various pitchers in the past and their hitting outcomes against upcoming pitchers: swinging too early, failing to take bad pitches, etc, says Zack Hample in “Watching Baseball Smarter.”

Clearly, pitchers too can iPod-review what hitters have done against them. Of course, charts and videos can’t recreate the experience players get by facing each other, as they may do many times over the course of a season, “learning each other’s tendencies the old-fashioned way.”

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