Geology Rocks :: Q & A

Modern geology started in the 18th century. Before then geology and theology were widely one and the same with people such as Georges Cuvier (1769-1832) and Abraham Werner (1749-1817) trying to interpret the rocks around them in terms of biblical events, especially Noah's Flood. It wasn't until James Hutton (1726-1797), a graduate of the University of Edinburgh, that modern geology was born. Hutton believed that many of the rocks we see today were formed from remnants of older, more ancient rocks. In 1778, Hutton wrote:

"We find no sign of a beginning - no prospect for an end"

Hutton was referring to the fact that the processes going on today (beaches, waves, tides, rivers, deserts), were occurring in the past and it was these processes that were responsible for building up rocks. Hutton gave this idea the name uniformatarianism, which means building up rocks from slow but steady process, rather than the cataclysmic view of the time. This was neatly summed up by Sir Archibald Geike (1835-1924), who coined the phrase: "the present is the key to the past", demonstrating that modern processes acted in the past exactly as they do now.

This view was highly controversial at the time, as many "geologists" believed the Earth to be a mere few thousands of years old. Modern processes did not accumulate enough sediment quickly enough to form the vast thicknesses of rocks seen in this small time frame. A classic location where Hutton showed that geological time was vast and that rocks could be separated by large stretches of time was at Siccar Point (S.E Scotland), where he wrote (1795):

...at Siccar Point, we found a beautiful picture of this junction [between Silurian and Devonian] washed bare by the sea. The sandstone strata are partly washed away, and partly remaining upon the ends of the vertical schistus; and, in many places, points of the schistus strata are seen standing up through among the sandstone, the greatest part of which has been worn away.

This is a description of an unconformity (see here for a picture of it). Although Hutton's work was pioneering, it wasn't widely accepted until Charles Lyell (another Scot) (1779-1875) wrote Principles of Geology in 1830. This book was the first modern geology textbook and brought Hutton's theories to the public.

The first geological map was produced by William Smith (1769-1839), when he produced a geological map of Britian in 1815. Again this was largely overlooked at the time. In 1830, Smith was awarded the Wollaston Medal from he Geological Society of London, the society's highest honour in recognition of his work.

How and where did geology begin?

Early History of Geology

References