https://padlet.com/3048881/8xhemoxwceq9 en-us 2018-01-16 20:14:19 UTC 2018-01-16 20:38:55 UTC hello@padlet.com 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221874696 The geologic time scale (GTS) is a system of chronological dating that relates geological strata (stratigraphy) to time. It is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events that have occurred during Earth's history.]]> 2018-01-16 20:16:12 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221874696 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221875344 In geology and related fields, a stratum (plural: strata) is a layer of sedimentary rock or soil, or igneous rock where formed at the earth's surface, with internally consistent characteristics that distinguish it from other layers.]]> 2018-01-16 20:18:02 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221875344 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221875954 In order to determine the age of a geologic material, we must understand the concept of half-life. Half-life is a term that describes time. The definition is: The time required for one-half of the radioactive (parent) isotopes in a sample to decay to radiogenic (daughter) isotopes.]]> 2018-01-16 20:19:53 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221875954 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221878355 the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.]]> 2018-01-16 20:27:10 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221878355 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221879038 The history of Earth concerns the development of planet Earth from its formation to the present day. Nearly all branches of natural science have contributed to the understanding of the main events of Earth's past. The age of the Earth is approximately one-third of the age of the universe.]]> 2018-01-16 20:28:56 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221879038 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221879365 An idealized cycle of processes undergone by rocks in the earth's crust, involving igneous intrusion, uplift, erosion, transportation, deposition as sedimentary rock, metamorphism, remelting, and further igneous intrusion.]]> 2018-01-16 20:30:01 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221879365 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221879786 A method of dating geological or archeological specimens by determining the relative proportions of particular radioactive isotopes present in a sample.]]> 2018-01-16 20:31:24 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221879786 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221880615 Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties ofradiocarbon (14. C), a radioactive isotope of carbon.]]> 2018-01-16 20:33:59 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221880615 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221881046 Radioactive decay (also known as nuclear decay or radioactivity) is the process by which an unstable atomic nucleus loses energy (in terms of mass in its rest frame) by emitting radiation, such as an alpha particle, beta particle with neutrino or only a neutrino in the case of electron capture, gamma ray, or electron ]]> 2018-01-16 20:35:26 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221881046 3048881 https://padlet.com/3048881/8xhemoxwceq9/wish/221881830 The age of the Earth is approximately 4.54 ± 0.05 billion years (4.54 × 10⁹ years ± 1%). This dating is based on evidence from radiometric age-dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar samples.]]> 2018-01-16 20:37:58 UTC https://padlet.com/3048881/8xhemoxwceq9/wish/221881830