This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
March 17, 1785 the "famous philosopher of the fossils" & agronomist James Hutton presented to the Royal Society his "dissertation", "Concerning the System of the Earth, Its Duration, and Stability." For the first time he proposed in public his theory that Earth was much older than previously believed. One of the most important evidence for his theory was an outcrop along the rugged coast of Siccar Point in Scotland. Here two geologic formations are separated by a so called "unconformity".
Fig.1. The angular unconformity at Siccar Point, one of the key outcrops for Hutton to demonstrate the validity of his theory. This illustration was made by Sir James Hull in 1788, during an excursion lead by Hutton.
Hutton, observing the different tilted layers of the sediments, realized that the gap between these layers was telling a complex geologic history:
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- 1) Once the strata of the first formation had to be slowly deposited horizontally in the sea,
- 2) then uplifted and tilted.
- 3) Once again above the sea level, erosion took place, working slowly but incessant to remove the rocks.
- 4) Again tectonic movements took place and pushed the remaining rock-formation below the sea level.
- 5) Here again sedimentation slowly accumulated layers of sediments to form a new geologic formation.
- 6) Finally, the two formations were pulled above sea level, where eventually geologist could observe and study them for a brief (geological) time, before future erosion will again dismantle the rocks...
Ever single step represents a vast period of time, not even considering the time lost in the missing, because eroded rocks, truly, as Hutton will write in his "Theory of the Earth" in 1788 "we find no vestige of a beginning, no prospect of an end."
Now this keystone of earth's history is threatened by the construction of a pipeline for agricultural wastes (oh, the Irony…). Geologists - but not only - all over the world should oppose to this short-sighted approach and Save Siccar Point !!*
*Addendum : As pointed out to me, Siccar Point itself is a Site of Special Scientific Interest (SSSI) since 1961. The pipeline will not (!) enter the protected area of Siccar Point and the area surrounding the protected site is already used for farming (with various canals ending in the sea). An issue - under scrutiny at the moment - remains possible biological waste of unspecified composition washed by currents or tides ashore on the site.