Thursday, March 1, 2007

Just A Little Longer ...


Image credit: U.S. Geological Survey (USGS)

Sometimes waiting can make time seem to stretch into geological scale. When you're waiting for the one bit of justice you're likely to see for some of the worst people to run our government in a very long time, you have to keep reminding yourself that these things take time. Like parents do on a cross-country road trip, we keep saying "Just a little longer ...".

Speaking of geological ages, today's "clock" is a way of measuring geological time:

In 1962, scientists of the U.S. Naval Oceanographic Office prepared a report summarizing available information on the magnetic stripes mapped for the volcanic rocks making up the ocean floor. After digesting the data in this report, along with other information, two young British geologists, Frederick Vine and Drummond Matthews, and also Lawrence Morley of the Canadian Geological Survey, suspected that the magnetic pattern was no accident. In 1963, they hypothesized that the magnetic striping was produced by repeated reversals of the Earth's magnetic field, not as earlier thought, by changes in intensity of the magnetic field or by other causes. Field reversals had already been demonstrated for magnetic rocks on the continents, and a logical next step was to see if these continental magnetic reversals might be correlated in geologic time with the oceanic magnetic striping. About the same time as these exciting discoveries were being made on the ocean floor, new techniques for determining the geologic ages of rocks ("dating") were also developing rapidly.

Magnetic stripes and isotopic clocks

Even the direction of magnetic north changes over time, sometimes dramatically. That's some comfort considering what we're going through these days.

While the eons pass before our eyes, check in at FDL. Christy Hardin Smith has an examination of what the Libby trial tells us about the press. Oh, and according to emptywheel, the jury needed more sticky notes. She also looks at the essay I pointed out the other day by Jim Marcinowski.

Oh, and ever the class guy, John McCain announced he's running for President on a talk show. As always with McCain, the press went out of its way in the linked article to paint him as a maverick:

McCain has also irked the GOP's social conservative base by refusing to back a constitutional amendment barring gay marriage saying the issue is a matter for the states.

Well, at least we have that. Go read the article. It's worse than I let on.

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