https://padlet.com/304522/qv1shtcnvmlr Vocabulary 1/22 en-us 2018-01-22 16:21:43 UTC 2025-09-28 11:25:32 UTC hello@padlet.com 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223412194 The geologic time scale is a system of chronological dating that relates geological strata to time.]]> 2018-01-22 16:24:54 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223412194 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223412459 In geology and related fields, a stratum (plural: strata) is a layer of sedimentary rock or soil, or igneous rockthat were formed at the earth's surface, with internally consistent characteristics that distinguish it from other layers.]]> 2018-01-22 16:25:19 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223412459 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223412755 The Rock Cycle is a group of changes. Igneous rock can change into sedimentary rock or into metamorphic rock. ]]> 2018-01-22 16:25:50 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223412755 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223413016 the remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.]]> 2018-01-22 16:26:13 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223413016 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223413262 The history of Earth concerns the development of planet Earth from its formation to the present day.]]> 2018-01-22 16:26:37 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223413262 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223414154 the time required for any specified property (e.g., the concentration of a substance in the body) to decrease by half.]]> 2018-01-22 16:28:05 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223414154 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223414207 a method of dating geological or archeological specimens by determining the relative proportions of particular radioactive isotopes present in a sample.]]> 2018-01-22 16:28:11 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223414207 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223414759 Radiocarbon, or carbon 14, is an isotope of the element carbon that is unstable and weakly radioactive. ... Carbon 14 is continually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen 14 atoms.]]> 2018-01-22 16:29:06 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223414759 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223414931 Radioactive decay (also known as nuclear decay orradioactivity) is the process by which an unstable atomic nucleus loses energy (in terms of mass in its rest frame) by emitting radiation]]> 2018-01-22 16:29:26 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223414931 304522 https://padlet.com/304522/qv1shtcnvmlr/wish/223415027 The age of the Earth is approximately 4.54 ± 0.05 billion years (4.54 × 10⁹ years ± 1%).]]> 2018-01-22 16:29:36 UTC https://padlet.com/304522/qv1shtcnvmlr/wish/223415027