Catastrophism and uniformitarianism Processes that change Earth’s Surface

Catastrophism Defined as- Geologic change that happens quickly.

Catastrophism During the Formation of Earth series of large, violent, quick, worldwide upheavals changed the earth greatly and produced mountains, valleys, and various other large scale features In changing Earth’s surface once in a while, sudden and widespread catastrophes would hit the planet and wipe out a number of species. These catastrophes were natural events, like volcanoes, earthquakes, and floods, and they would also change Earth’s landscape.

Catastrophism Continued Consider Mt. St. Helens http://www.youtube.com/watch?v=hNTeOjo5Cvs

Japan Tsunami

Indonesian Earthquake/Tsunami

Uniformitarianism A principle that states that geologic processes that occurred in the past can be explained by current geologic processes.

Uniformitarianism- This theory states the following During the Formation of Earth Geologists found that features of Earth changed slowly over long periods of time, they called it gradualism, also known as uniformitarianism. gradual processes (such as for example the slow erosion of the coast by the impact of waves) shaped the geologic record of the earth over an immensely long period of time In changing Earth’s surface the acting processes were the same as those that we see in action at present (rivers, volcanoes, waves, tides etc.) extremely rare (and catastrophic) events, such as the impact of large meteors, may have had a profound influence on our planet.

Uniformitarianism

Modern Geology The combination of sciences of uniformitarianism and catastrophism is called modern geology.

Paleontology Defined as the scientific study of fossils Scientist who study fossils are called paleontologist.

Sum it up- Take a minute and be prepared to Share the following Give a three word description of uniformitarianism. Give a three word description of catastrophism. How do these geoscience processes change Earth’s surface over time?