PPT-The Geologic Time Scale Mass extinctions

999 of all living things that have ever existed on earth have gone extinct earth has experienced 5 five extinctions Geologic time scale Era Largest unit of geologic time lasts tens to hundreds of millions of years and consists of two or more periods . Chapter 21.1, 22, 23, 24. Why do we care?. By studying the characteristics of rocks and fossils within them, geologists can interpret. The environment the rocks were deposited in. Reconstruct Earth’s history. 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).. 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. Very general images. What is with the . zig. . zag. ? . Has the earth cooling-shows really deep time!. Shows Cambrian Explosion period.. Mentions algae and eukaryotic cells.. Has all groups! Nice sense of how things evolved. Not straight hard to follow. Hard to tell . 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).. To learn how the geologic timeline was made and how the length of the various periods are different. Agenda. Progress reports – need to be signed by Parent/guardian. Geologic History Notes. Project –highlights. Organization of . Ch. 21-24. Ch. 21.1 – Describes the geologic time scale. Ch. 22 – Precambrian Earth. . Section 1: Early Earth. . Section 2: Formation of the Crust and Continents. . Section 3: Formation of the Atmosphere and Oceans. 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. 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.. La gamme de thé MORPHEE vise toute générations recherchant le sommeil paisible tant désiré et non procuré par tout types de médicaments. Essentiellement composé de feuille de morphine, ce thé vous assurera d’un rétablissement digne d’un voyage sur . ___When you started second grade. ___When you were born. ___ When you started kindergarten. ___When you learned to ride a bike.. ___ When you learned to walk.. ___ When you learned to read.. ___ When you lost your first tooth.. Essential Questions. What is extinction?. Which species have become extinct in modern times? . What are the characteristics of past mass extinctions? . How do modern extinction rates compare with natural (background) rates?. Extinction . When an organism is classed as extinct there are no living members of that species left. Extinction is a natural process where organisms that are less suited to an environment die out. Throughout the history of earth there have been several mass extinction events .