PPT-Fossils, Geologic Time, Absolute & Relative Dating, and Natural Resources

Fossils Geologic Time Absolute amp Relative Dating and Natural Resources Chapters 5 amp 6 How Do Fossils Form Fossils are found in sedimentary rocks like sandstone limestone and shale In Virginia most fossils are. 01: . Geologic Time . Scale. Huge sections of time are broken down into smaller groups of time:. E. ons, Eras, . P. eriods, and . E. pochs. Eon. is the largest time block. . (kind of like what we would think of as years).. 01: . Geologic Time . Scale. Huge sections of time are broken down into smaller groups of time:. E. ons, Eras, . P. eriods, and . E. pochs. Eon. is the largest time block. . (kind of like what we would think of as years).. Relative Age Dating of Rocks. Put these people in order from youngest to oldest.. A. B. C. D. Relative age Dating of Rocks. Can you tell the exact ages of these people?. Dating. Relative age dating- . Fossils. Fossils provide a window into the past as they provide evidence about the changes that have occurred to the Earth over the 4.5 billion years of existence.. A . fossil . is the preserved evidence in rocs or soils of organisms that once existed on Earth.. 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 (. Earth is very, very old…. Earth’s History. The history of Earth and the ages of rocks can be investigated and understood by studying rocks and fossils.. Evidence of ancient, often extinct life is preserved in many sedimentary rocks.. Relative Dating. To . determine the relative age of different rocks, geologists start with the assumption that unless something has happened, in a sequence of sedimentary rock layers, the newer rock layers will be on top of older ones. This is called the Rule of Superposition.. 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 (e.g. a granite dike is younger than the surrounding sandstone since it intrudes across the sandstone in an outcrop).. Favs. .. . Where do sediments come from?. - Weathering. – breaking down rock into smaller pieces chemically and physically.. - Erosion. - carrying away the particles and depositing them. . Glaciers. Folds, Faults and Deformities…. OH MY!!. Uniformitarianism. Geologic processes that occurred in the past can be explained by current geologic processes. Erosion and weathering that happens today must have been the same millions of years ago. Relative age dating:. Age of a rock compared to other rocks. Used to understand a sequence of events. What are the ways to tell . RELATIVE AGE. .. 1. Law of Superposition (Undisturbed) . 2. Extrusion & Intrusion (Igneous Rock). Absolute and relative white cells count Absolute value (leukocytes/mm 3 = Total leukocyte count ( cells/mm 3 X Relative value(%) Example: Total leukocyte count = 6000 Segmented forms (relative no.) = 50 % 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. Today’s Objective:. . How Do Scientist Figure Out A Numerical Age For Rocks? . Do Now. :. Using the diagram to the right what is the difference between relative dating and absolute dating? . What is a jiffy .