EARTH-FRIENDLY GEOTHERMAL ENERGY:

“The glass vases on the shelf rattled, and there was a loud bang,” Catherine Wueest, a teashop owner, recalls. “I thought a truck had crashed into the building.”

But the 3.4 magnitude tremor on the evening of Dec. 8 was no ordinary act of nature: It had been accidentally triggered by engineers drilling deep into the Earth’s crust to tap its inner heat and thus break new ground — literally — in the world’s search for new sources of energy. . . .

In Basel, the first shaft was bored last year by a 190-foot-tall drilling rig towering above nearby apartment buildings. Water was pumped down the injection well in the test phase in December, and as expected, it heated to above 390 F as it seeped through the layers of rock below.

But that’s where the water remains for the time being; it caused the rock layers to slip, causing the tremors and rumbles that spooked the townspeople.

Geopower Basel, had forecast some rock slippage. In fact, it said the location on top of a fault line — the upper Rhine trench — was an advantage because it meant the heat was closer to the Earth’s surface.

Oops.