https://padlet.com/3045482/zyhv3rr4v32c Made with joy en-us 2018-01-22 16:21:45 UTC 2026-01-22 16:31:15 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/Pictureland.png 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223412404 A system of chronological dating that relates geological strata to time.]]> 2018-01-22 16:25:15 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223412404 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223412595 a layer of sedimentary rock or soil, or igneous rock that were formed at the earth's surface.]]> 2018-01-22 16:25:33 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223412595 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223412708 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.]]> 2018-01-22 16:25:44 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223412708 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223412741 the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.]]> 2018-01-22 16:25:48 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223412741 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223412901 The development of planet Earth from its formation to the present day.]]> 2018-01-22 16:26:00 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223412901 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223412981 the time taken for the radioactivity of a specified isotope to fall to half its original value.]]> 2018-01-22 16:26:11 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223412981 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223413408 a method of dating geological or archeological specimens by determining the relative proportions of particular radioactive isotopes present in a sample.]]> 2018-01-22 16:26:52 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223413408 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223413565 the determination of the age or date of organic matter from the relative proportions of the carbon isotopes carbon-12 and carbon-14 that it contains. The ratio between them changes as radioactive carbon-14 decays and is not replaced by exchange with the atmosphere.]]> 2018-01-22 16:27:06 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223413565 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223413691 The spontaneous transformation of an unstable atomic nucleus into a lighter one, in which radiation is released in the form of alpha particles, beta particles, gamma rays, and other particles.]]> 2018-01-22 16:27:20 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223413691 3045482 https://padlet.com/3045482/zyhv3rr4v32c/wish/223413763 The Earth is a little over 4.5 billion years old, its oldest materials being 4.3 billion-year-old zircon crystals]]> 2018-01-22 16:27:26 UTC https://padlet.com/3045482/zyhv3rr4v32c/wish/223413763