THE   PRINCIPLES   OF   UNIFORMITARIANISM AND CATASTROPHISM!!!!

                          IN 1795, A PHILOSOPHER AND SCIENTIST NAMED JAMES HUTTON CAME UP WITH THE THEORY OF THE EARTH, WHERE HE STATED THAT THE EARTH'S LANDFORMS ARE CONSTANTLY CHANGING. HE ALSO ASSUMED THAT THESE CHANGES RESULT FROM GEOLOGIC PROCESSES SUCH AS THE BREAKDOWN OF ROCK AND THE TRANSPORT OF SEDIMENT THAT REMAIN AND DON'T CHANGE OVER TIME. HE CALLED HIS ASSUMPTION UNIFORMITARIANISM.

The Moine Thrust: Understanding geology: unconformities

This is short animation of on unconformities and a scrollable geological history.

A Dynamic Earth

Uniformitarianism is the principle that states the same geologic processes shaping the Earth today have been at work throughout Earth's history. " The present is the key to the past" is a phrase that best summarizes Uniformitarianism.

Hutton observed gradual, uniform geologic processes at work. Judging by the slowness of the processes, he concluded that the Earth must be incredibly old.

HUTTON OBSERVED NATURAL FORCES BREAKING DOWN INTO SMALLER PARTICLES.

HE WATCHED RIVERS CARRIED ROCK PARTICLES DOWNSTREAM.

HE SAW THAT ROCK PARTICLES ARE DEPOSITED AND THAT  THEY FORM NEW LAYERS OF SEDIMENT. HE PREDICTED THAT THESE DEPOSITS WOULD EVENTUALLY FROM NEW ROCK.

HUTTON THOUGHT THAT IN THE TIME THE NEW ROCK WOULD BE UPLIFTED, CREATING NEW LANDFORMS, AND THAT THE CYCLE WOULD START OVER AGAIN.

   Catastrophism- is a principle that states that all geologic change occurs suddenly.

    SUPPORTERS OF CATASTROPHISM CLAIMED THAT THE FORMATION OF ALL EARTH'S FEATURES, SUCH AS ITS MOUNTAINS, CANYONS, AND SEAS, COULD BE EXPLAINED BY RARE, SUDDEN EVENTS CALLED CATASTROPHES. THESE UNPREDICTABLE CATASTROPHES CAUSED RAPID GEOLOGIC CHANGES OVER LONG AREAS SOMETIMES GLOBALLY.   

  Despite Hutton's observations, Catastrophism remained geology's guiding principle for decades. it took the work of Charles Lyell, another scientist, for people to seriously consider Uniformitarianism.

       From 1830 to 1833, Lyell published three volumes collectively titled Principle of Geology, he reintroduced uniformitarianism. Armed with Hutton's notes and new evidence of his own, Lyell successfully changed the principle of Catastrophism. Lyell saw no reason to doubt that major geologic change happened the same way in the past as it does in the present - gradually.