PPT-GY111 Physical Geology Geologic Time Measurement

Geological Clocks Geologic time determination is subdivided into 2 categories Relative Dating simply determines whether or not an event occurs before or after another event eg a granite dike is younger than the surrounding sandstone since it intrudes across the sandstone in an outcrop. Comparison of Conventional & Short-Age Geology. Faith, Reason, and Earth History. Chapter 14. by Dr. Leonard Brand. Short-age. Geology. Conventional. Geology. Assumptions. Interpretations. Challenges. Evolution of the Continents. Important Terms. Craton: interior of continents made of stable Precambrian and Paleozoic . rocks.. Shield: portion of Craton composed of older Precambrian . rocks.. Platform: portion of Craton made of younger Paleozoic . In depth: chapter 19. Geologic Time Scale. Examining layers of sedimentary rock, scientists have put together a chronology of Earth’s history.. It is divided into 4 Eras:. 1. Precambrian (3.5 . bya. 8. th. Grade Science. Geologic Time. Geologic time. . - Earth’s history is divided into units of time that make up the . Geologic . T. ime . S. cale. .. Time units on the scale are based on the appearance (. Who was James Hutton?. In the late 1700s, James Hutton began to question some of the ideas regarding the Earth.. He found fossils and saw them as evidence of life forms that no longer exist. . Different types of fossilized creatures were found in different layers of rock.. “Civilization exists by geologic consent” -Will Durant. Where are the world’s great cities located and why?. Why are Earliest Humans Here?. East African Rift. Water. Animals. Preservation of fossils. Atoms & Atomic Particles. An atom is the smallest component of an element that can retain the properties of that element. Atoms are composed of fundamental particles:. Protons. Neutrons. Electrons. Instructor: Dr. Scott T. Marshall. All . Science . is . Based . on . The Scientific Method. Today’s . Theme:. What is Geology?. The study of the Earth. Composition. Behavior. History. Geology is often called geoscience or Earth science. Faith, Reason, and Earth History. Chapter 14. by Dr. Leonard Brand. Short-age. Geology. Conventional. Geology. Assumptions. Interpretations. Challenges. Starting Assumptions. Affect how scientists interpret data. Section 12.1 Discovering earth’s history. Uniformitarianism – the idea that physical, chemical, and biological laws that operate today also operated in the past; the present is the key to the past.. a. Fossils. 3. Geologic Time Scale. 4. Geologic Belts. 5. NC Geologic History. How do we know . geologic . history. ?. Earth's History. Earth's history spans over a length of . 4.5 billion . years. Geologists have divided that time into units based on major geologic events and life forms. Normally we think of time in terms of days or years but geologists commonly refer to events that happened millions or billions of years ago. For example earth is approximately 4.6 billion years old. GEOLOGIC TIME. Stress & Strain. Stress: a force applied to an area.. Example: tire pressure in psi.. Strain: a change in original shape or volume (produced by stress).. Elastic strain: analogous to a steel spring or rubber band.. Important Terms. Craton: interior of continents made of stable Precambrian and Paleozoic rocks.. Shield: portion of Craton composed of older Precambrian rocks.. Platform: portion of Craton made of younger relatively undeformed Paleozoic sediments..