at Siccar Point this morning gave me goosebumps. An innocuous sign along a farm road points one to a grassy cliff top trail that ends at the outcrop that challenged centuries of Church doctrine that the Earth was only 6,000 years old (click to enlarge):
Although Hutton and his companions (John Playfair and Sir John Hall) arrived by wooden sailboat in 1788, the view from the cliff top is especially impressive, with the vertically-dipping Silurian greywackes jutting forth from the sea:
After negotiating a very steep down climb to the outcrop, the classic view of the angular unconformity is clearly presented, with the near horizontal beds of the Devonian red sandstones overlying the older tilted beds:
The index finger of my left hand points to the unconformable contact where 55 million years of Earth history is missing (unknown in 1788), but still suggesting to Hutton that a long expanse of time must have passed, and that the Earth was indeed very, very old:
Playfair later wrote about the visit to this now famous outcrop that "the mind seemed to grow giddy by looking so far into the abyss of time." I can't say that I was giddy today, but I was certainly profoundly humbled, to have had the opportunity to visit this magnificently historic place. Priceless.
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