radiometric
Decay rate based
Radiometric describes measurement techniques based on the emission or absorption of radiation.
In geology, radiometric dating determines the age of rocks and fossils by measuring the decay of radioactive isotopes: Radiometric analysis placed the sample at 4.5 billion years old.
The term also applies to measuring electromagnetic radiation in remote sensing and astronomy.
Predominant uranium isotope
- carbon-14Radioactive isotope for dating
- potassium-40Naturally radioactive potassium isotope
- half-lifePeriod for fifty-percent reduction
- decayGradual organic breakdown
alpha · beta · gamma · nucleus · neutron · proton · transmutation · nuclide
Radioactive isotope for dating
- potassium-argonIsotopic age-determination technique
- uranium-leadIsotopic age-determination method
- thermoluminescenceLight from heated irradiated material
- radiocarbonDecaying carbon isotope
Final Mesozoic period
- JurassicDinosaur-dominated geological period
- PermianLate Paleozoic geological period
- CambrianEarliest Paleozoic period
- megafaunaSpecies over 44 kilograms
dinosaurs · hominid · Paleolithic · Neolithic · paleoanthropology · prehistoric · ancient
Formed from cooled magma
- metamorphicUndergoing structural change
- zirconZirconium silicate crystal
- crystallizationForming ordered solid structure
- magmaMolten rock underground
volcanic · plutonic · bedrock · geothermal · intrusion · tuff · apatite
uranium-238
Predominant uranium isotope
- carbon-14Radioactive isotope for dating
- potassium-40Naturally radioactive potassium isotope
- half-lifePeriod for fifty-percent reduction
decay · alpha · beta · gamma · nucleus · neutron · proton · transmutation · nuclide
carbon-14
Radioactive isotope for dating
- potassium-argonIsotopic age-determination technique
- uranium-leadIsotopic age-determination method
- thermoluminescenceLight from heated irradiated material
radiocarbon · geochronology · calibration · chronometry · accelerator
Cretaceous
Final Mesozoic period
- JurassicDinosaur-dominated geological period
- PermianLate Paleozoic geological period
- CambrianEarliest Paleozoic period
megafauna · dinosaurs · hominid · Paleolithic · Neolithic · paleoanthropology · prehistoric · ancient
igneous
Formed from cooled magma
- metamorphicUndergoing structural change
- zirconZirconium silicate crystal
- crystallizationForming ordered solid structure
magma · volcanic · plutonic · bedrock · geothermal · intrusion · tuff · apatite
Neanderthal
Extinct archaic human species
radiometricoptical
Of vision or light
mechanical · photometric · visual · acoustic · magnetic
- radiometric datingAge measurement via atomic decay