|North and Basket Domes (L) and Half Dome (R)|
The Sierra batholith is a huge expanse of granite shaped like a blimp. It has an exposed surface area of about 25,000 square miles, and is thought to have an internal volume of some 150,000 cubic miles. Many years before I was born, plumes of molten magma rose deep beneath the earth’s crust, much like weather balloons might fill an airplane hanger. Their ascent stopped by the impenetrable roof, the magma plumes retained their balloon shapes as they slowly cooled into what we now know as granite.
But nature is never finished. In the late 1970s, California was hit by several years of severe drought. Despite the efforts of numerous hikers who hand carried literally thousands of bottles of Perrier to the base of the pine, the famous Sentinel Jeffrey Pine died. It is unknown whether the pine died from the stress of the drought or merely from old age. Or maybe it was the Perrier. I hear that part of President Obama’s stimulus package includes a grant to scientifically prove that the tree’s death was actually a result of George W. Bush’s failed policies. What remains certain, however, is that the tree is no longer emitting vital signs.