I. The Ozarks region is one of the oldest and most unique geologic regions in North America

II. Three of the four main geologic eras are represented in the Ozarks

  1. Paleozoic Era (800 to 225 million years ago)
  2. Mesozoic Era (225 to 65 million years ago)
  3. Cenozoic Era (65 million to present time)
  4. Gradual but persistent erosion then began to take place which formed what we now know as the Ozarks Plateau
II. The result of these combined events was the formation of a geologic phenomena known as Karst
  1. Karst is characterized by the following elements
  2. Other areas of the world characterized by Karst are;
  3. The development of Karst is a systematic process
III. while the Ozarks have been gradually free of earthquakes, one of the most serious earthquakes in North American history took place in the region
  1. Occurred on December 16, 1811
  2. Located in Southeast Missouri near the town of New Madrid
  3. Aftershocks and tremors lasted for months afterward
  4. No recorded loss of life occurred due to the sparsely settled population
  5. Greatest manifestation of the quake was the creation of Reelfoot lake in Western Tennessee which is 70 miles long, 20 miles wide and as deep as 100 feet in some areas.