PPT-Geologic Principles &

Relative Dating How old is the Earth The Earth is about 46 billion years old Much of its history is recorded in the rocks Observations of fossils rock types evidence of faulting uplift and folding as well as igneous . GEOL 2110. Lecture 2. Scales of Time and Change. Major Concepts. Geological events cover huge amounts of time that are hard to grasp in the span of human life. We tend to focus on dramatic, short-lived geologic events that we witness and are unaware of subtle, but geologically important events . How long ago were the dinosaurs here? How do we even describe geologic time anyway?. EONS. which are divided into . ERAS. ,. which are divided into. . PERIODS. ,. which are divided into. . EPOCHS. Mapping, spectroscopy and geologic analysis of Earth’s “sister” planet. Venus. The Basics, pre-1960. Radius 95% of Earth, mass 82%. 92X Earth atmospheric pressure, 97% CO2. 462°C surface temp. Mesozoic. Cambrian and Ordovician. Cenozoic. Pre-Belt. Pre-Cambrian. Paleozoic. Page. 1. Geologic Timeline . For example, using fossils, geologists can compare certain geologic strata in Montana with the "type section" of Devonian age rocks in Devon, England and determine that their ages are the same. Radiometric dates tell us that Devonian rocks fall in a range of 369–410 million years ago.. INDEX . FOSSILS . (brief, but widespread). HOW . MUCH PLATES HAVE . MOVED ALL OVER. . . . show how Earth went from . Pangeae. to how it is today in only 230 million years. 71 million years ago, India was down in the southern hemisphere.. 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.. 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).. “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. The geologic time scale divides Earth’s long history into units of time…. Eras. .  . Periods. .  . Epochs. Eras. are divided into . P. eriods. .. Periods. are divided into . Epochs. .. Precambrian. 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.